СТАТИЧЕСКИЙ ПРЕОБРАЗОВАТЕЛЬ ЧАСТОТЫ И ПОДМОДУЛЬ СТАТИЧЕСКОГО ПРЕОБРАЗОВАТЕЛЯ ЧАСТОТЫ ДЛЯ ЗАРЯДКИ ИЛИ РАЗРЯДКИ НАКОПИТЕЛЯ ЭНЕРГИИ

Изобретение относится к преобразовательной технике. Для получения подмодуля (13) для зарядки или разрядки накопителя (22) энергии с конденсаторным блоком (14) и схемой (15) силовых полупроводниковых приборов, содержащей подключаемые и отключаемые силовые полупроводниковые приборы (16, 17), причём конденсаторный блок (14) и схема (15) силовых полупроводниковых приборов соединены друг с другом таким образом, что в зависимости от управления силовыми полупроводниковыми приборами (16, 17) на выходных зажимах (19, 20) подмодуля (1) формируется напряжение, падающее на конденсаторе, или нулевое напряжение, причем подмодуль (13) обеспечивает индивидуальное согласование процесса зарядки с требованиями соответствующего накопителя энергии и, кроме того, является недорогим, предлагается, чтобы накопитель (22) энергии подсоединялся к подмодулю (13) через стабилизатор (21) постоянного напряжения, причем чтобы стабилизатор (21) постоянного напряжения был соединен с конденсаторным блоком (14) и был оборудован ...

ЭЛЕКТРОННАЯ СХЕМА ДЛЯ ПРЕОБРАЗОВАНИЯ ЭЛЕКТРИЧЕСКОЙ ЭНЕРГИИ И УСТАНОВКА ЭЛЕКТРОПИТАНИЯ, В КОТОРОЙ ОНА ИСПОЛЬЗУЕТСЯ

Многоуровневый преобразователь содержит конденсатор (С1, C2, ..., Сn) в каждой из своих ячеек. Конденсаторы номинально имеют напряжения заряда, пропорциональные их соответственным порядковым номерам в преобразователе. Преобразователь включает также средство (VМ01, VМ02, ..., VM0n) оценки среднего напряжения на клеммах каждого из конденсаторов (С1, С2, ..., Сn), средство (VЕ1, VE2, ..., VЕn) измерения любой разности, которая может появиться в отношении каждого из конденсаторов (С1, С2, ..., Сn) между полученным в результате оценки средним напряжением заряда и номинальным средним значением заряда конденсатора, и для обеспечения соответствующего сигнала разности (VEC1, VEC2, . .., VЕСn), а также средство управления коррекцией (ВТ, ЕС1, ЕС2, ..., ЕСn), принимающее упомянутые сигналы разности и вызывающее установление по меньшей мере одного временного соединения между двумя конденсаторами для коррекции этой разности. Техническим результатом является повышение точности поддержания напряжения.

СИЛОВАЯ ЯЧЕЙКА С ПЕЧАТНЫМИ ПЛАТАМИ И РАЗВЯЗКОЙ И МНОГОЯЧЕЕЧНЫЙ ИСТОЧНИК ЭЛЕКТРОПИТАНИЯ СРЕДНЕГО НАПРЯЖЕНИЯ

Изобретения относятся к силовым ячейкам с печатными платами (ПП) и развязкой и к многоячеечным источникам электропитания среднего напряжения. Технический результат – обеспечение компактного источника электропитания, в котором развязка по напряжению встроена в отдельные силовые ячейки, а не является частью конструкции источника электропитания, за счет чего возможно более близкое размещение силовых ячеек друг к другу. Достигается тем, что предложенная силовая ячейка (100) с ПП для расположения в многоячеечном источнике (500) электропитания включает в себя узел (102) корпуса, содержащий непроводящий материал, с многосекционным корпусом (104, 106), и узел (120) ПП, расположенный внутри узла (102) корпуса, которые сконфигурированы для обеспечения встроенной изоляции по напряжению силовой ячейки (100). Снаружи узла корпуса на передней стороне силовой ячейки (100) размещены входные плавкие предохранители (132) для защиты от сверхтока либо в цепи источника, либо в цепи нагрузки, функционально соединенные ...

СПОСОБ И УСТРОЙСТВО УПРАВЛЕНИЯ ГИБРИДНОЙ СИСТЕМОЙ ПЕРЕДАЧИ ПОСТОЯННОГО ТОКА

Использование: в области электротехники. Технический результат – обеспечение эффективного управления напряжением и током гибридной системы электропередачи постоянного тока, не допуская перебоев в электропередаче. Способ управления гибридной системой электропередачи постоянного тока включает в себя: регулировку общего количества вставленных подмодулей модульного многоуровневого преобразователя и полярности выходного уровня вставленных подмодулей в режиме реального времени под напряжение постоянного тока выпрямительной подстанции на другом конце или регулировку общего количества вставленных подмодулей модульного многоуровневого преобразователя и полярности выходного уровня вставленных подмодулей в режиме реального времени под величину постоянного тока или мощность постоянного тока; регулировку общего количества вставленных подмодулей модульного многоуровневого преобразователя и полярности выходного уровня вставленных подмодулей в режиме реального времени под величину постоянного тока и напряжение ...

УПРЕЖДАЮЩЕЕ УПРАВЛЕНИЕ С ОТСЛЕЖИВАНИЕМ ОПОРНОГО УРОВНЯ

... 1. Способ управления электрическим преобразователем (10), характеризующийся тем, что электрический преобразователь содержит множество полупроводниковых ключей (16), при этом электрический преобразователь выполнен с возможностью генерировать двухуровневое или многоуровневое выходное напряжение из входного напряжения путем переключения множества полупроводниковых ключей (16);указанный способ включает шаги, на которыхпринимают опорную электрическую величинуи действительную электрическую величину (i);определяют последовательность будущих электрических величин электрического преобразователя (10) исходя из указанной действительной электрической величины;определяют максимальную величину затрат на основе указанной последовательности будущих электрических величин;итерационно определяют оптимальную последовательность переключений для электрического преобразователя (10), причем последовательность переключений содержит последовательность будущих состояний переключения для указанных полупроводниковых ...

Многоуровневое силовое преобразовательное устройство

СПОСОБ ФОРМИРОВАНИЯ ВЫХОДНОГО НАПРЯЖЕНИЯ И УСТРОЙСТВО ДЛЯ ОСУЩЕСТВЛЕНИЯ СПОСОБА

... 1. Способ формирования изменяемого по частоте выходного напряжения uпосредством модульного многоуровневого выпрямителя тока (М2С), причем выпрямитель тока посредством подключения и отключения подмодулей формирует аппроксимируемое дискретным ступенями напряжения синусоидальное переменное напряжение с первой круговой частотой ω, которая лежит между нулевой частотой ω,, и второй круговой частотой ω,, из входного напряжения U, отличающийся тем, что входное напряжение Uв зависимости от круговой частоты ωв диапазоне между нижней круговой частотой ω, которая равна или больше, чем нулевая частота ω, и круговой частотой ωдля снижения затрат на конденсаторы в выпрямителе тока управляется или регулируется таким образом, что оно возрастает с возрастанием частоты.2. Способ по п. 1, отличающийся тем, что подключение и отключение по меньшей мере одного подмодуля осуществляется ступенчато.3. Способ по п. 1 или 2, отличающийся тем, что подключение и отключение по меньшей мере одного подмодуля осуществляется ...

СИСТЕМА АККУМУЛИРОВАНИЯ ЭЛЕКТРИЧЕСКОЙ ЭНЕРГИИ

ПРЕОБРАЗОВАТЕЛЬ, ЭЛЕКТРИЧЕСКАЯ МНОГОФАЗНАЯ СИСТЕМА И СПОСОБ, В КОТОРОМ ИХ ПРИМЕНЯЮТ

ПРЕОБРАЗОВАТЕЛЬ, ОСНАЩЕННЫЙ МОДУЛЕМ УПРАВЛЕНИЯ ЭНЕРГИЕЙ В ПЕРЕМЕННОЙ ЧАСТИ

ПОДМОДУЛЬ, ЗАЩИТНЫЙ БЛОК, ПРЕОБРАЗОВАТЕЛЬ И СПОСОБ УПРАВЛЕНИЯ ПРЕОБРАЗОВАТЕЛЕМ

КОНФИГУРАЦИИ МОДУЛЬНОЙ МНОГОУРОВНЕВОЙ ПОДВОДНОЙ ЭНЕРГЕТИЧЕСКОЙ УСТАНОВКИ

... 1. Энергоснабжающая установка (10), содержащая источник (20) питания переменного тока, выполненный с возможностью подачи электроэнергии к одному или нескольким токоприемникам переменного тока через шину (14) передачи постоянного тока, которая содержит посылающий конец и принимающий конец, причем посылающий конец присоединен к одному набору модульных преобразователей (12) электроэнергии, выполненных с конфигурацией многоуровневого модульного преобразователя электроэнергии, а принимающий конец присоединен к другому набору модульных преобразователей (13) электроэнергии, выполненных с конфигурацией многоуровневого модульного преобразователя электроэнергии, при этом конфигурация указанного многоуровневого модульного преобразователя электроэнергии на принимающем конце симметрична конфигурации указанного многоуровневого модульного преобразователя электроэнергии на посылающем конце. ! 2. Энергоснабжающая установка (10) по п.1, в которой один или несколько токоприемников переменного тока непосредственно ...

Solid state capacitive ladder-type DC=AC converter - comprises electronically-controlled series parallel switching network that sequentially charges and discharges row of capacitors

The outputs (19,20) of a d.c. current source (1) are fed via a polarity reversing switch (9) to a row of parallel capacitors (13 to 18). The capacitors are enclosed within four banks of switches (24 to 29, 31 to 36, 37 to 42 and 50 to 54), all of which are governed by a master switching controller (23). Depending on the settings of the control (6,7) and polarity (8) potentiometers, the switching controller alternately charges the capacitors via switch banks (31 to 36 and 37 to 42) and discharges the capacitors in a series/parallel sequence via switch banks (24 to 29, 37 to 42 or 31 to 36 and 50 to 54) to produce a summed potential that approximates to an ac signal. This voltage is passed to an ac load (30) via supply lines (11 and 55). USE/ADVANTAGE - Compact, stable and efficient converter that utilises electronic switching to produce finely graduated waveform.

Elektronische Vorrichtung zur elektrischen Energieumwandlung

Spannungsangleichungssystem-Schaltungssystem

Es ist ein Angleichungs-Schaltungssystem bereitgestellt, das eine Systemkonfiguration aufweist, die durch eine Reduktion der Gesamtzahl von Schaltern vereinfacht ist. Eine Stromspeicherzellen-Spannungsangleichungs-Schaltung wird mit einer Rechteckspannung betrieben, die an einem Schaltknoten in einer Stromspeichermodul-Spannungsangleichungs-Schaltung als eine Eingangsspannung erzeugt wird, wodurch eine Stromspeicherzellen-Spannungsangleichungs-Schaltung ohne einen Schalter erreicht wird. Typischerweise kann es sich bei der Stromspeicherzellen-Spannungsangleichungs-Schaltung um eine Resonanz-Spannungs-Verdopplungs-Gleichrichterschaltung handeln, und bei der Stromspeichermodul-Spannungsangleichungs-Schaltung kann es sich um einen geschalteten Kondensator, eine Resonanz-Spannungs-Verdopplungs-Gleichrichterschaltung, einen Tief-Hochsetzsteller oder dergleichen handeln.

Umrichteranordnung sowie Verfahren zu deren Betrieb

Die Erfindung bezieht sich u. a. auf eine Umrichteranordnung (10) mit zumindest einer Reihenschaltung (R1, R2, R3) mit mindestens zwei in Reihe geschalteten Teilmodulen (T), die jeweils mindestens einen Schalter (S1, S2) aufweisen und jeweils an einem vorgegebenen elektrischen Einbauplatz (EP1, EP2, EPn) der Umrichteranordnung (10) eingebaut sind, und einer mit den Teilmodulen (T) in Verbindung stehenden Zentraleinheit (200) zum Ansteuern der Teilmodule (T). Erfindungsgemäß ist vorgesehen, dass die Teilmodule (T) jeweils einen Speicher (130) aufweisen, in dem eine das jeweilige Teilmodul (T) eindeutig identifizierende Kennung (SNR), insbesondere Seriennummer, abgespeichert ist, und die Teilmodule (T) jeweils eine Steuereinrichtung (120) aufweisen, die die abgespeicherte Kennung (SNR) über eine das jeweilige Teilmodul (T) und die Zentraleinheit (200) verbindende Kommunikationsverbindung an die Zentraleinheit (200) übermitteln kann.

Stromrichter

Modul (201) eines modularen Multilevelstromrichters (1), das mindestens zwei elektronische Schaltelemente (202, 206) und einen elektrischen Energiespeicher (210) aufweist, dadurch gekennzeichnet, dass - das Modul (201) einen nichtflüchtigen elektronischen Speicher (230) zum Speichern von während des Betriebs des Moduls ermittelten Statusinformationen des Moduls aufweist.

Vorrichtung zum Umrichten eines elektrischen Stromes

Inverter und Photovoltaikanlage

Der Inverter ist insbesondere ein Mikro-Photovoltaik-Inverter. Der Inverter weist eingangsseitig einen Gleichspannungswandler mit drei Ausgangsspannungsniveaus sowie einen daran elektrisch angebundenen Wechselrichter mit mindestens drei Eingangsspannungsniveaus auf. Die Photovoltaikanlage weist einen Mikro-Photovoltaik-Inverter mit solch einem Inverter auf.

Umrichter, elektrisches Polyphasen-System und Verfahren zum effizienten Leistungsaustausch

Die vorliegende Erfindung betrifft einen modularen Multilevel-Umrichter (10) mit einer Mehrzahl von Einzelmodulen (12), die jeweils eine Mehrzahl von Schaltelementen und mindestens einen elektrischen Energiespeicher aufweisen, wobei eine erste Anzahl von Einzelmodulen (12) hintereinander zu einem geschlossenen Ring verschaltet sind, und mindestens zwei Abgriffe (14) jeweils zwischen zwei benachbarten Einzelmodulen (12) des Rings angeordnet sind, wobei zwischen zwei benachbarten Abgriffen (14) mindestens ein Einzelmodul (12) des Rings angeordnet ist, das ein Ringsegment bildet, und wobei an mindestens zwei Abgriffen je eine zweite Anzahl von Einzelmodulen als von der Ringanordnung (11) abzweigendes und einen Sternstrang bildendes Phasenmodul (20) aus mindestens zwei Einzelmodulen (12) vorgesehen ist, das mit einem Ende an dem jeweiligen Abgriff (14) angeschlossen ist und an dem anderen Ende einen Phasenanschluss bildet, wobei die Mehrzahl von Schaltelementen ein Verschalten von Energiespeichern ...

Inverter vom I-Typ mit drei Niveaus und Halbleitermodul

Ein Inverter vom I-Typ mit drei Niveaus enthält erste bis vierte Schaltvorrichtungen zwischen ersten und zweiten Potentialen, erste bis vierte Dioden und fünfte und sechste Dioden. Die ersten bis vierten Dioden sind jeweils mit den ersten bis vierten Schaltvorrichtungen antiparallel verbunden. Zwischen einem Verbindungsknoten der ersten und zweiten Schaltvorrichtungen und einem Verbindungsknoten der dritten und vierten Schaltvorrichtungen sind fünfte und sechste Dioden in Reihe und mit einer Reihenschaltung der zweiten und dritten Schaltvorrichtungen antiparallel verbunden. Ein Verbindungsknoten der fünften und sechsten Dioden ist mit einem Eingangsknoten mit einem Zwischenpotential verbunden. Ein Verbindungsknoten der zweiten und dritten Schaltvorrichtungen ist mit einem Ausgangsknoten verbunden. Die zweite Schaltvorrichtung und Diode sind aus einem ersten, rückwärts leitenden IGBT gebildet. Die dritte Schaltvorrichtung und Diode sind aus einem zweiten, rückwärts leitenden IGBT gebildet ...

Verfahren und Vorrichtung zur Steuerung eines modularen Multilevelkonverters mittels neuronaler Netze

Die Erfindung betrifft ein Verfahren zu einer Steuerung eines modularen Multilevelkonverters mittels eines neuronalen Netzes, bei dem der modulare Multilevelkonverter als eine Hardware und auf ein numerisches Modell abgebildet als eine Software vorliegt, bei dem zu einem jeweiligen Zeitpunkt vorliegende Schaltzustände der Module des modularen Multilevelkonverters als ein jeweiliger Zustandsvektor dargestellt werden, bei dem durch einen jeweiligen Zustandsvektor mindestens ein Istspannungslevel des modularen Multilevelkonverters zu dem jeweiligen Zeitpunkt realisiert wird, bei dem mindestens eine Eingangsgröße des neuronalen Netzes von mindestens einer vorgegebenen Betriebsgröße des modularen Multilevelkonverters zu dem jeweiligen Zeitpunkt gebildet wird, bei dem von dem neuronalen Netz als eine Ausgangsgröße der für einen nächsten Zeitpunkt auf dem modularen Multilevelkonverter zu schaltende nächste Zustandsvektor gebildet wird, wobei in einem ersten Schritt das neuronale Netz trainiert ...

HEV-E-Antriebe mit HV-Hochsetzverhältnis und breitem Gleichstromverteilerspannungsbereich

Die vorliegende Offenbarung stellt HEV-E-Antriebe mit HV-Hochsetzverhältnis und breitem Gleichstromverteilerspannungsbereich bereit. Ein System beinhaltet einen Verteiler und einen variablen Spannungswandler (VVC), der einen Schalter, der mit einem Kondensator in Reihe geschaltet ist, und einen Induktor beinhaltet, der mit dem Kondensator und dem Schalter parallel geschaltet ist, und derart konfiguriert ist, dass der Betrieb des Schalters in einem Verstärkungsmodus über einen Aussteuerungsbereich von 0 bis weniger als 0,5 einen entsprechenden Spannungsausgang an den Verteiler von 0 bis zu einem Maximum des VVC bewirkt.

EINE WANDLERVORRICHTUNG UND EIN VERFAHREN ZUR STEUERUNG DERSELBEN

Inverter circuit and method for operating an inverter circuit

An inverter circuit 110 comprises a series-connected arrangement of two switching elements 145, 147, connected in series between an input connection 150 and a first intermediate connection 152. Both switching elements have a parallel connected arrangement of a controllable switch T5, T6 and a diode D5, D6, where the first diode D5 is poled in a direction other than that of the second diode D6. A third switching element 155 is disposed between the first intermediate connection and the output connection 140, having a parallel connected arrangement of a third controllable switch T2 and a third diode D2 having its cathode connected to the first intermediate connection and its anode connected to the output connection. A fourth switching element 160 is disposed between the output connection 140 and a second intermediate connection 157, having a parallel connected arrangement of a fourth controllable switch T3 and a fourth diode D3 having its cathode connected to the output connection and its ...

Power converter sub-module

Fault protection for voltage source converters

Converter

Voltage source converter and control thereof

A voltage source converter (VSC) 200, especially for use in High Voltage Direct Current (HVDC) power distribution/transmission, has at least one phase limb having a high-side DC terminal DC+, a low-side DC terminal DC- and an AC terminal 202. A voltage wave-shaper 204 provides a selectively variable voltage level Vws. Each phase limb also has a switch arrangement SU1, SU2, SL1, SL2 operable to provide at least first and second switch states. In the first switch state the low-side DC terminal is electrically connected to the AC terminal via a first path that includes the voltage wave-shaper. In the second switch state the high-side DC terminal is electrically connected to the AC terminal via a second path that includes the voltage wave-shaper. The voltage wave-shaper may comprise a chain-link circuit including a series of cells 104b, each having an energy storage element, such as a capacitor, 107 and a cell switch arrangement 105 operable to selectively connect the energy storage element ...

Converter

A converter 30, particularly a bidirectional converter for a HVDC power transmission network, comprises at least one limb connected between first and second DC terminals 32,34. Each limb includes a phase element 36 having a plurality of switching elements 40 and at least one AC terminal for connection to an AC network 50. The plurality of switching elements are switchable to selectively interconnect a DC side 58 voltage of the phase element and an AC side voltage, where each switching element has forward and reverse voltage blocking capabilities. At least one DC side sub-converter 38,39, operable as a voltage synthesiser, is connected to the DC side of the phase element. The converter further includes a controller 60 to selectively control the switching of the switching elements of the phase element to control the operation of the DC side sub-converter of each limb as a voltage synthesiser. The controller also controls the switching of the switching elements of the phase elements to provide ...

Power converter

CONTROLLABLE COMPOUND VOLTAGE DC/AC TRANSFORMING CIRCUIT

SYSTEM FOR GENERATING AN AC VOLTAGE OF CONSTANT FREQUENCY FROM A ROTATING SHAFT

Improvements in or relating to converters

Apparatus and methods for providing electrical converter control parameters

Open switch fault detection and identification in a two-level voltage source power converter

Controller for synthesizer circuit for generating three-tier waveforms

A method and apparatus for producing control signals for operating an inverter circuit to convert a DC voltage into multitiered steplike notched N phase AC output signals (N=some positive integer number other than zero). A plurality of N reference sine waves are generated 90 DEG out of phase with one another for N=2, and for N greater than 2, successive ones of said N reference sine waves are generated 360 DEG /N out of phase with each other. First through third triangular sampling or timing waveforms are generated and concurrently compared with the uppermost, central and lowermost portions, respectively, of each individual one of said N reference sine waves, for producing N sets of first, second and third pulse width modulated pulse trains, respectively. Decoding logic networks are receptive of these N sets of first through third pulse trains, for decoding these pulse trains into the necessary control signals for operating a particular inverter circuit.

Converter comprising a power supply unit and a control circuit

A d.c./a.c. converter synthesizes an alternating voltage by suitably and at the correct instants selectively combining a plurality of direct voltage sources into a variety of series connections by means of a plurality of semiconductor controlled switches and diodes. Polarity inversion is effected with a bridge circuit comprising switches. The converter load is connected to said bridge circuit. In this way it is possible to directly generate a 220 V, 50 Hz AC voltage without inductive elements, from solar panels, using accumulator batteries.

Method and system for a safety concept for an AC battery

... a method for a safety concept for an AC battery, in which the AC battery comprises a central controller, a plurality of battery modules which have a power board with a plurality of switching states, a plurality of contactors, a plurality of current sensors, a fault loop and a high-speed bus and is connected to a traction machine, wherein the central controller has a hardware programmable processor unit with at least one microprocessor core on which a control program is configured to control the battery modules, the plurality of contactors and the fault loop, and a state machine is implemented by means of the control program, wherein the battery modules are connected, starting from the central controller, via the high-speed bus and the fault loop, wherein, if an abort fault occurs, the AC battery is changed to a safe operating state by emergency disconnection of the central controller, by a “bypass” switching state on each battery module and a respective safety switching position of each ...

INVERTER

PROCEDURE FOR THE ENTERPRISE OF A THREE-PHASE STATIC FREQUENCY CHANGER CIRCUIT

ELECTRONIC DEVICE FOR ELECTRICAL ENERGY CONVERSION

GRADUATED ONE AND COUPLING BATTERY VOLTAGE REGULATION COMBINE WITH A DIRECT CURRENT MOTOR REGULATION WITH FELDREGELUNG

ELECTRONIC ENERGY CONVERSION CIRCUIT AND THIS USING POWER GENERATION PLANT

INVERTER

INVERTER

INVERTER

INVERTER

INVERTER

INVERTER

INVERTER

INVERTER

INVERTER

Multi-level multi-quadrant hysteresis current controllers and methods for control thereof

Hybrid multilevel inverters

A method comprises during a first half cycle, configuring a first switch to operate as an always-on switch, turning on a second switch prior to turning on a third switch and turning off the third switch prior to turning off the second switch, wherein the first switch and the second switch are connected in series and further in parallel with the third switch between a first terminal of a power source and a filter and during a second half cycle, configuring a fourth switch to operate as an always-on switch, turning on a fifth switch prior to turning on a sixth switch and turning off the sixth switch prior to turning off the fifth switch, wherein the fourth switch and the fifth switch are connected in series and further in parallel with the sixth switch between a second terminal of the power source and the filter.

Power converter

Device for converting multicell energy

A resonant converter

ELECTRIC CAR CONTROL APPARATUS

In an electric car control apparatus for driving an induction motor, detection accuracy of a DC voltage is improved. A DC power supply device is provided which has a maximum potential terminal A, an intermediate potential terminal B, a minimum potential terminal C, an upstream side capacitor 6 between the maximum potential terminal A and the intermediate potential terminal B, and a downstream side capacitor 7 between the intermediate potential terminal B and the minimum potential terminal C. Also, an overvoltage suppression part is provided which includes a resistor 8 and a thyristor 9 between the maximum potential terminal A and the minimum potential terminal C. Further, provision is made for a downstream voltage sensor 10 between the intermediate potential terminal B and the minimum potential terminal C, an upstream voltage sensor 11 between a junction of the resistor 8 and the thyristor 9 and the intermediate potential terminal B, and a three level inverter 3 connected to the maximum ...

METHOD FOR OPERATING A DIRECT CONVERTER CIRCUIT AND DEVICE TO CARRY OUT THE METHOD

The invention relates to a method for operating a direct converter circuit, wherein the power semiconductor switches of the switchgear cells (2) of the associated phase module (1) are actuated by means of an actuating signal (S1). In order to reduce undesired energy fluctuations on the phase modules (1), for each phase module (1) the actuating signal (S1) is formed from the difference of a reference signal (Vref,UR, Vref,us, Vref,ut, Vref,vR, Vref,vs, Vref,vt, Vref,wR, Vref,ws, Vref,wt) with respect to the voltage (UUR, UUS, UUT; UVR, UVS, UVT; UWR, UWS, UWT) over the phase module (1) and a voltage signal (VLUR, VLUS, VLUT, VLVR, VLVS, VLVT, VLWR, VLWS, VLWT) over the inductivity (LUR, Lus, Lut; LVR, LVS, LVT; LWR, LWS, LWT), wherein the voltage signal (VLUR, VLUS, VLUT, VLVR, VLVS, VLVT, VLWR, VLWS, VLWT) is formed over the inductivity (LUR, Lus, Lut; LVR, LVS, LVT; LWR, LWS, LWT) from a reference signal (iref.UR, iref.US, iref.UT, iref.VR, iref.VS, iref.VT, iref.WR, iref.WS, iref,WT) ...

CONVERTER

A voltage source converter (37) for use in high voltage DC power transmission and reactive power compensation. The voltage source converter (37) comprises at least one converter limb (34) including first and second DC terminals (36, 38) for connection in use to a DC network (22) and an AC terminal (44) for connection in use to an AC network (20). The or each converter limb (34) defines first and second limb portions (34a, 34b), each limb portion (34a, 34b) including at least one switching element (40) connected in series with a chain-link converter (42) between a respective one of the first and second DC terminals (36, 38) and the AC terminal (44). The switching elements (40) of the first and second limb portions (34q, 34b) is operable to switch the respective chain-link converters (42) in and out of circuit between the respective DC terminal (36, 38) and the AC terminal (44). The chain-link converters (42) are operable to generate a voltage waveform at the AC terminal (44).

RECTIFIER CIRCUIT

A rectifier circuit for at least one phase (R, S, T) is disclosed, which includes a first vector group system (1), provided for each phase (R, S, T), comprising a first main vector group (4), formed by a power semiconductor switch and a capacitor (3), connected to the power semiconductor switch (2) and with at least one intermediate group (7), formed by two serially-connected controlled power semiconductor switches (5) and a capacitor (6), said intermediate group(s) (7) being connected to the first main vector group (4). The first vector group system further comprises a second main vector group (9), formed by a power semiconductor switch (8), whereby the or an intermediate group (7) is connected to the second main vector group (9). According to the invention, the rectifier circuit may be simplified and the incidence of faults reduced, whereby the power semiconductor switch (2), the first main vector group (4) and the power semiconductor switch (8) in the second main vector group (9) are ...

REDUNDANT ENERGY ACQUISITION CIRCUIT OF POWER MODULE, AND CONTROL METHOD THEREOF

The present application provides a redundant energy acquisition circuit of a power module and a control method thereof. The power module comprises at least one power semiconductor device, a first capacitor, and a first branch circuit switch, and is characterized in that the redundant energy acquisition circuit of the power module comprises: a first power supply board acquiring energy from the first capacitor, supplying power to a control board, and charging a discharge circuit; a first charging circuit having one terminal connected to a positive electrode of the first capacitor and another terminal connected to the discharge circuit, and charging the discharge circuit when the power supply board is not operating normally; the control board controlling the discharge circuit to close; and the discharge circuit discharging and triggering the first branch circuit switch to close after the discharge circuit has been closed.

BYPASS THYRISTOR VALVE GROUP INSPECTION METHOD AND CONTROL APPARATUS

Disclosed are a bypass thyristor valve group inspection method and control device, used for inspection of submodules in a bypass thyristor valve group. The method specifically comprises: dividing a bypass thyristor valve group into N submodules, wherein N is a natural number greater than or equal to 2, and each submodule is formed by connecting one or more thyristors in series; under the condition that the thyristor valve group is subjected to a normal forward voltage, sequentially triggering the submodules by a bypass thyristor valve group control device according to a certain time period, detecting whether each submodule is capable of operating normally, and if not, sending an alarm signal. By means of the bypass thyristor valve group inspection method and control device, the thyristor performance monitoring problem under a condition that a bypass thyristor valve group does not operate for a long time is effectively solved, and safety in operation of a protected voltage source current ...

CONVERTER AND POWER CONVERSION APPARATUS INCLUDING THE SAME

A converter includes a first diode having an anode and a cathode connected respectively to an input terminal and a first output terminal, a second diode having an anode and a cathode connected respectively to a second output terminal and the input terminal, a first transistor connected between the first output terminal and the input terminal, a second transistor connected between the input terminal and the second output terminal, and a bidirectional switch connected between the input terminal and a third output terminal and including third to sixth diodes and a third transistor. Each of the first diode, the second diode, and the third transistor is made of a wide bandgap semiconductor. Each of the first and second transistors and the third to sixth diodes is made of a semiconductor other than the wide bandgap semiconductor.

MULTI-LEVEL HIGH SPEED ADJUSTABLE SPEED DRIVE

A multi-level high-speed adjustable speed drive has a plurality of modular multilevel, 3-phase inverter bridges, wherein the multilevel, 3-phase inverter bridges operate with fundamental frequency, f, wherein the multilevel, 3-phase inverter bridges include at least three levels, wherein the multilevel, 3-phase inverter bridges operate in Pulse-Width Modulation (PWM) mode with 9 to 21 x or operating in Fundamental Frequency Mode (FFM), wherein inverter commutation frequency equals the fundamental frequency, wherein the multilevel, 3-phase inverters operate with split phase such that one group is displaced from the other by an angle, ? = 60/q, wherein the phase displacement of a harmonic component of order n between groups, ?n is n? /q; a high-speed polyphase motor with phases arranged in q 3-phase groups; and electromagnetic means for blocking selected groups of harmonics while passing components at fundamental frequency, f, wherein the electromagnetic means includes coils carrying motor ...

METHOD AND APPARATUS FOR CONTROLLING HYBRID DIRECT-CURRENT TRANSMISSION SYSTEM

A method and apparatus for controlling a hybrid direct-current (DC) transmission system. The method comprises: adjusting the total number of inserted sub-modules of a modular multi-level converter and the polarity of an output level of the inserted sub-modules in real time, according to a DC voltage of a rectifier station at other end; or adjusting the total number of inserted sub-modules of a modular multi-level converter and the polarity of an output level of the inserted sub-modules in real time, according to the magnitude of a DC current or DC power; or adjusting the total number of inserted sub-modules of a modular multi-level converter and the polarity of an output level of the inserted sub-modules in real time, according to both the magnitude of the DC current and the DC voltage of the rectifier station at the other end. The method can effectively control the DC voltage and the direct current of a hybrid DC transmission system, avoiding the power transmitting breakdown.

METHOD AND APPARATUS FOR CONTROLLING HYBRID DIRECT-CURRENT TRANSMISSION SYSTEM

A method and apparatus for controlling a hybrid direct-current transmission system. The method comprises: the hybrid direct-current transmission system adjusting, according to a direct-current voltage of a rectifier station at the other end, the total number of input sub-modules of a modular multi-level converter and the polarity of an output level of the input sub-modules in real time, or adjusting, according to the magnitude of a direct current or direct-current power, the total number of the input sub-modules of the modular multi-level converter and the polarity of the output level of the input sub-modules in real time, or adjusting, according to both the magnitude of the direct current and a direct-current voltage of the rectifier station at the other end, the total number of the input sub-modules of the modular multi-level converter and the polarity of the output level of the input sub-modules in real time. The method can effectively control a direct-current voltage and a direct current ...

CONVERTER CIRCUIT FOR SWITCHING A LARGE NUMBER OF SWITCHING VOLTAGE LEVELS

... ²A converter circuit is specified for switching a large ²number of switching voltage levels, which has n first ²switching groups for each phase. The nth first switching ²group is formed by a first and a second power semiconductor ²switch and the first first to the (n-1)th switching groups ²are each formed by a first and a second power semiconductor ²switch and by a capacitor connected thereto. Each of the n ²first switching groups is connected in series to the ²respectively adjacent first switching group and the first ²and second power semiconductor switches in the first first ²switching group are connected to one another. To reduce the ²amount of electrical energy stored in the converter ²circuit, n .gtoreq. 1 and p second switching groups and p third ²switching groups are provided, which are each formed by a ²first and a second power semiconductor switch and by a ²capacitor connected thereto.² ...

CONTROL OF A MODULAR CONVERTER WITH DISTRIBUTED ENERGY STORES

The invention relates to a device (1) for converting an electrical current, comprising at least one phase module (2a, 2b, 2c), having an AC connection (3/1, 3/2, 3/3) and at least one DC connection (p, n). A phase module branch (6p1, 6p2, 6p3, 6n1, 6n2, 6n3) is provided between each DC connection and each AC connection. Each phase module branch has a series connection made of sub-modules (7), which in turn comprise an energy accumulator (8) each and at least one power semiconductor (T1, T2). The device further comprises measuring sensors for providing actual values and control means (9, 10) connected to the measuring sensors. The control can be easily adapted to any arbitrary number of sub-modules in each phase module branch. The control means (9, 10) comprise a current regulating unit (10) and control units (9) associated with a phase module branch each, wherein the current regulating unit (1) is configured to provide branch target values for the control units (9). The control units are ...

MODEL PREDICTIVE CONTROL WITH REFERENCE TRACKING

An electrical converter (10) comprising a plurality of semiconductor switches (16), wherein the electrical converter is adapted for generating a two-level or multi-level output voltage from an input voltage by switching the plurality of semiconductor switches (16). A method for controlling the electrical converter (10) comprises the steps of: receiving a reference electrical quantity (i S *) and an actual electrical quantity (i S ); determining a sequence of future electrical quantities of the electrical converter (10) from the actual electrical quantity; determining a maximal cost value based on the sequence of future electrical quantities; iteratively determining an optimal switching sequence for the electrical converter (10), wherein a switching sequence comprises a sequence of future switching states for the semiconductor switches of the electrical converter; and selecting the first switching state of the optimal switching sequence as the next switching state (u) to be applied to the ...

A NEW FOUR-LEVEL CONVERTER CELL TOPOLOGY FOR CASCADED MODULAR MULTILEVEL CONVERTERS

A cascaded modular multilevel converter has a plurality of 4-level converters, each ac phase generates the multilevel voltage waveforms composed of different outputs of the modules in the same phase. Each module is a controlled voltage source. The number of voltage levels in the cascaded converter is determined by the number of modules in each phase and the voltage levels generated by each module. N cascaded 4-level converters generate 4N+1 phase-to-neutral voltage levels and 8N+1 phase-to-phase voltage levels.

METHOD OF CONTROLLING THE SWITCHING OF A MULTILEVEL CONVERTER, A CONTROLLER FOR A MULTILEVEL CONVERTER, AND A COMPUTER PROGRAM FOR CONTROLLING A CONVERTER

A method of controlling a multilevel converter, a computer program and a controller for a converter is provided. The method includes determining a transition voltage (vstep) from a control period (k) to a following control period (k+1), analyzing (104) the switching cells (SC1, SC2, SC3, SCn) of each phase leg, selecting (111) capacitors to provide the transition voltage and synthesize the output voltage for the following control period (k+1), and connecting (113) the selected capacitors during the following control period (k+1). Especially, the analyzing (104) of each switching cell (SC1; SC2; SC3; SCn) comprises analyzing (104) a first switching leg (SL1) and a second switching leg (SL1) of the switching cell (SC1; SC2; SC3; SCn), and the method includes determining (105) whether a change of state of the first switching leg (SL1) would contribute to the direction of the transition voltage, and determining (105) whether a change of state of the second switching leg (SL2) would contribute ...

MULTILEVEL POWER CONVERSION DEVICE

A multilevel power conversion device comprises: N DC power supplies (DCC1 to DCCN) (N = 1) connected in series and common to each phase; first flying capacitors (FC1, FC3, , FC2N-1) having one end connected to the negative electrode end of each of the DC power supplies (DCC1 to DCCN) and common to each phase; a second flying capacitors (FC2, FC4, , FC2N) having one end connected to the positive electrode end of each of the DC power supplies (DCC1 to DCCN) and common to each phase; and a phase module using, as input terminals, the positive and negative electrode ends of the first flying capacitors (FC1, FC3, , FC2N-1) and the positive and negative electrode ends of the second flying capacitors (FC2, FC4, , FC2N). In the phase module, a capacitor (FC1u) is connected in parallel with the two switching elements (Su7, Su8) of an output stage. This reduces the number of elements used in a multiphase multilevel power conversion device, thereby reducing the cost of the device and reducing the size ...

CAPACITOR BALANCING CIRCUIT AND CONTROL METHOD FOR AN ELECTRONIC DEVICE SUCH AS A MULTILEVEL POWER INVERTER

A method of balancing voltages in a group of capacitors of a power electronic device, such as a multilevel power inverter, includes making a balancing determination regarding whether to (i) inject energy into the selected one of the capacitors from an energy storage element, or (ii) extract energy from the selected one of the capacitors into the energy storage element based on the voltage of a selected one of the capacitors, and either injecting energy into the selected one of the capacitors from the energy storage element, or extracting energy from the selected one of the capacitors into the energy storage element based on the balancing determination. Also, a voltage balancing circuit that implements the method. In one particular implementation, a spatial second derivative algorithm is used. In another particular implementation, a comparison to an average capacitor voltage is used.

VOLTAGE BALANCING SYSTEM AND METHOD FOR MULTILEVEL CONVERTERS

A method of operating a flying capacitor multilevel converter having a direct current link and a plurality of phase legs each having a plurality of flying capacitors includes employing redundant states to balance flying capacitor voltages by charging or discharging flying capacitors. The redundant states are employed by obtaining a load current of the flying capacitor multilevel converter. If a load current value is lower than a threshold value then a capacitor current of a phase terminal capacitor is utilized to determine redundant states else a load current direction is utilized to determine the redundant states.

METHOD FOR ENERGIZING A CHAIN-LINK CONVERTER, CONTROLLER, COMPUTER PROGRAMS AND COMPUTER PROGRAM PRODUCTS

The invention relates to a method 60 in a controller 50 for energizing a chain-link converter 30 comprising one or more phase legs L1, L2, L3, each phase leg L1, L2, L3 comprising a number of series-connected converter cells 311, 312,..., 31n, each converter cell 311, 312,..., 31n comprising four valves arranged in an H-bridge connection with a DC capacitor 341, 342,..., 34n. Each valve in turn comprises a semiconductor switch 321, 322, 323, 324 in parallel with a diode 331, 332, 333, 334. The method 60 comprises the steps of: charging 61 the DC capacitor 341, 342,..., 34n of each converter cell 311, 312,..., 31n to a voltage level at which the semiconductor switches are controllable but below their nominal voltage; diagnosing 62 the converter cells 311, 312,..., 31n so as to detect failed components thereof; bypassing 63 faulty components in a controlled manner; charging 64 the DC capacitors 341, 342,..., 34n to their nominal voltage. The invention also relates to a controller, computer ...

METHOD FOR ENERGIZING A CHAIN-LINK CONVERTER, CONTROLLER, COMPUTER PROGRAMS AND COMPUTER PROGRAM PRODUCTS

The invention relates to a method 60 in a controller 50 for energizing a chain-link converter 30 comprising one or more phase legs L1, L2, L3, each phase leg L1, L2, L3 comprising a number of series-connected converter cells 311, 312,..., 31n, each converter cell 311, 312,..., 31n comprising four valves arranged in an H-bridge connection with a DC capacitor 341, 342,..., 34n. Each valve in turn comprises a semiconductor switch 321, 322, 323, 324 in parallel with a diode 331, 332, 333, 334. The method 60 comprises the steps of: charging 61 the DC capacitor 341, 342,..., 34n of each converter cell 311, 312,..., 31n to a voltage level at which the semiconductor switches are controllable but below their nominal voltage; diagnosing 62 the converter cells 311, 312,..., 31n so as to detect failed components thereof; bypassing 63 faulty components in a controlled manner; charging 64 the DC capacitors 341, 342,..., 34n to their nominal voltage. The invention also relates to a controller, computer ...

CONVERTER ARRANGEMENT

POWER CONVERTER AND METHOD OF ASSEMBLING THE SAME

A power converter (114) includes a plurality of power conversion modules (152/154). At least one power conversion module includes a plurality of power conversion devices (S1/S2/S3/S4/D1/D2/D3/D4/D5/D6) defining a three-level bridge (200). A first power conversion module (152/154) includes four terminals including one of a positive terminal (T1) and a negative terminal (T5), an output terminal (T3/T7), a first neutral terminal (T2/T6), and a second neutral terminal (T4/T8). The first neutral terminal is coupled to a direct current (DC) link (136) and the second neutral terminal is coupled to a second power conversion module (154/152).

M2LC SYSTEM AND METHOD FOR CONTROLLING SAME

A modular multilevel converter system. The system includes a plurality of series connected two-terminal M2LC cells arranged into at least two output phase modules. A first one of the output phase modules has an inductance and an effective capacitance associated therewith. The first one of the output phase modules is configured so that a natural resonant frequency of the inductance with the effective capacitance of the first one of the output phase modules is greater than at least one of the following: an operating frequency of the first one of the output phase modules; a switching frequency of the first one of the output phase modules; and a switching frequency of any of the M2LC cells of the first one of the output phase modules.

HYBRID 2-LEVEL AND MULTILEVEL HVDC CONVERTER

A voltage source converter (10a) is used in high voltage direct current power transmission and reactive power compensation. The voltage source converter (10a) comprises first and second DC terminals (12, 14) for connection in use to a DC network (20), three phase elements (16) and at least one auxiliary converter (18) connected between the first and second DC terminals (12, 14), each phase element (16) including a plurality of primary switching elements (22) and at least one AC terminal (24) for connection in use to a respective phase of a multiphase AC network (26), the plurality of primary switching elements (22) being controllable in use to facilitate power conversion between the AC and DC networks (26, 20), the or each auxiliary converter (18) being operable in use to act as a waveform synthesizer to modify a first DC voltage presented to the DC network (20) so as to minimise ripple in the DC voltage.

ELECTRONIC DEVICE FOR CONVERTING ELECTRICAL ENERGY

Convertisseur multiniveaux comprenant notamment une source de tension (VE), une source de courant SC, et un condensateur (C1, C2..., Cn), pour chacune de ses cellules, ainsi que des moyens de commande comprenant des moyens d'évaluation d'un écart de courant éventuel entre un courant observé dans ladite source de courant (SC) et un courant demandé par cette source de courant (Iref), ainsi que des moyens de commande de marche (GRCn+1) pour prendre en compte ledit écart de courant éventuel et modifier en conséquence ladite durée du premier état de conduction de toutes les cellules du convertisseur dans un sens propre à réduire ledit écart de courant. Des moyens additionnels (GRCn+1) maintiennent l'ensemble des condensateurs flottants à leurs valeurs de tension d'équilibre.

Installation pour la constitution de tensions pilotes de commande de la commutation électronique d'un moteur à induction

Umformerschaltung zur Erzeugung einer nahezu sinusförmigen Spannung

Installation pour la constitution de tensions pilotes de commande de la commutation électronique d'un moteur à induction polyphasé

Circuit for a multi-level static frequency changer with thyristor change-over.

Diese Schaltung für einen Multilevel-Umrichter besteht aus einzelnen Zellen, welche aus einem Zwischenkreiskondensator, sowie für jede Phase aus 2 Halbleiterschaltern (S1N, S1P, S2N, S2P), 2 Freilaufdioden (D1N, D1P, D2N, D2P) und 2 Thyristoren (T1P, T1N, T2P, T2N) besteht. Die Zwischenkreise der Zellen werden in Serie zusammengeschaltet, die zu einer Phase gehörenden Thyristoren aller Zellen sind zusammengeschaltet und bilden den Phasenausgang des Umrichters. Bei jeder Phase ist jeweils ein Thyristor eingeschaltet, welcher so die für diese Phase aktive Zelle auswählt. Um das Umschalten der Thyristoren zu ermöglichen, wird eine zusätzliche Spannungsquelle benötigt.

Modular multilevel converter.

Die Erfindung betrifft einen modularen Multilevel-Stromrichter, der mehrere Phasen mit Phasenzweigen (11) aufweist, jeweils mit einem oberen Arm (111) und einem unteren Arm (112), wobei jeder der Arme (111, 112) eine serielle Verbindung einer Mehrzahl von MMC-Modulen und einer Arminduktivität (3) aufweist und die MMC-Module steuerbare Spannungsquellen sind. Es liegt dabei pro Phase ein aktives Filtermodul (4) vor, welches einen ersten Anschluss aufweist, der mit dem oberen Mittenanschluss der Phase verbunden ist, einen zweiten Anschluss, der mit dem unteren Mittenanschluss der Phase verbunden ist, und einen dritten Anschluss, der mit dem Phasenanschluss der Phase verbunden ist. Das aktive Filtermodul (4) weist eine Zwischenkreisspannung zwischen einem oberen Anschlusspunkt (P) und einem unteren Anschlusspunkt (N) auf, und für jeden der drei Anschlüsse des Filtermoduls (4) liegt jeweils ein Brückenzweig vor, mit welchem wahlweise der obere oder der untere Anschlusspunkt mit dem jeweiligen ...

Modularer Multilevel-Stromrichter.

Die Erfindung betrifft einen modularen Multilevel-Stromrichter, der mehrere Phasen mit Phasenzweigen (11) aufweist, jeweils mit einem oberen Arm (111) und einem unteren Arm (112), wobei jeder der Arme (111, 112) eine serielle Verbindung einer Mehrzahl von MMC-Modulen und einer Arminduktivität (3) aufweist und die MMC-Module steuerbare Spannungsquellen sind. Es liegt dabei pro Phase ein aktives Filtermodul (4) vor, welches einen ersten Anschluss aufweist, der mit dem oberen Mittenanschluss der Phase verbunden ist, einen zweiten Anschluss, der mit dem unteren Mittenanschluss der Phase verbunden ist, und einen dritten Anschluss, der mit dem Phasenanschluss der Phase verbunden ist. Das aktive Filtermodul (4) weist eine Zwischenkreisspannung zwischen einem oberen Anschlusspunkt (P) und einem unteren Anschlusspunkt (N) auf, und für jeden der drei Anschlüsse des Filtermoduls (4) liegt jeweils ein Brückenzweig vor, mit welchem wahlweise der obere oder der unteren Anschlusspunkt mit dem jeweiligen ...

Vorrichtung, verteiltes Modulationssystem und Verfahren für leistungselektronische Anwendungen.

Die Erfindung betrifft eine Vorrichtung (10, 20, 30) für ein verteiltes Modulationssystem für leistungselektronische Anwendungen, mit: mindestens einem Transceiver zum Empfangen von Steuerdaten von einem Steuermaster (10) über mindestens einen Datenübertragungskanal (201), der ein Referenztaktsignal (RefCLK) einbettet und mit mindestens einem Satz von Modulationsparametern, mindestens einem Taktwiederherstellungsmodul, das zum Wiederherstellen eines wiederhergestellten Taktsignals vom Datenübertragungskanal (201) angeordnet ist, einem Modulator, angeordnet zum Erzeugen von Modulationssignalen basierend auf dem Satz von Modulationsparametern und auf mindestens einem periodischen Träger, der unter Verwendung des wiederhergestellten Taktsignals erzeugt wird, einem Überwachungsmodul, das zum Mastern und Anpassen einer anfänglichen Phasendifferenz zwischen dem/n periodischen Träger(n) und einem Unterbrechungssignal basierend auf dem Referenztaktsignal konfiguriert ist. Die vorliegende Erfindung ...

M2LC SYSTEM AND METHOD OF CONTROL SYSTEM

METHOD AND DEVICE FOR DAMPING VOLTAGE HARMONICS IN A MULTILEVEL POWER CONVERTER

Non-isolated five-level inverter and leakage current boycotting strategy thereof

Multilevel converter

A power converter is presented. The power converter includes at least one leg operatively coupled between a first bus and a second bus and includes a first string including a plurality of non-controllable semiconductor switches, a first node, a second node, and a third node, where the first node is coupled to a third bus, one or more second strings, where each of the one or more second strings includes at least one fully controllable semiconductor switch, and where one of the second strings is coupled between the first node and the third bus and another second string is coupled between the second node and the third node, and one or more third strings, where each of the one or more third strings includes at least one energy storage device and is coupled to the first string, the one or more second strings, or a combination thereof.

Variable-switching-MMC frequency control method suitable for PWM single-phase motor

Device for converting an electric current

The invention relates to a device (1) comprising: at least one phase module (2a, 2b, 2c) with an A.C. voltage connection (31, 32, 33) and at least one d.c. voltage connection (p, n), a phase module branch (6p1, 6p2, 6p3, 6n1, 6n2, 6n3) being arranged between each d.c. voltage connection (p, n) and the a.c. voltage connection (31, 32, 33) and each phase module branch (6p1, 6p2, 6p3, 6n1, 6n2, 6n3) having a series circuit of sub-modules (7), each of which has an energy accumulator (8) and at least one power semiconductor (T1, T2); and regulating means for regulating the device. The aim of the invention is to provide a device that can regulate circulating currents in a targeted manner. To achieve this, each phase module (2a, 2b, 2c) has at least one inductance (Lkr) and the regulating means are designed to regulate a circulating current that flows through the phase modules (2a, 2b, 2c).

Power conversion device

Highly efficient half-bridge dc-ac converter

The invention relates to a DC to AC converter circuit. In particular, the invention relates to a half-bridge inverter for converting a DC to an AC voltage. The half-bridge inverter for converting a DC input voltage to provide an AC output voltage at an output terminal, comprising a first switching circuit connected to at least one input terminal and to the output terminal and configured to provide a high or a low voltage level at the output terminal; a second switching circuit connected to the output terminal and configured to provide a connection to an intermediate voltage level, the intermediate voltage level being between the high and the low voltage level; and wherein the second switching circuit is further connected to the at least one input terminal allowing the second switching circuit to provide the high or the low voltage level at the output terminal.

Submodule for a multi-stage power converter having additional energy storage device

A submodule for forming a multilevel power converter for electric energy distribution and transmission, includes a capacitor unit and a power semiconductor circuit having power semiconductors that can be switched off. The capacitor unit and the power semiconductor circuit are interconnected in such a way that, depending on the actuation of the power semiconductors of the power semiconductor circuit, at least the voltage released at the capacitor unit or a zero voltage can be generated at output terminals of the submodule. The submodule is not only able to compensate for reactive power, but to exchange active power with a connected alternating current network. An additional energy storage device is connected to the capacitor unit through a chopper unit for regulating current flow between the additional energy storage device and the capacitor unit.

System and Method For Controlling A M2LC System

A modular multilevel converter system. The system includes a plurality of series connected two-terminal M2LC subsystems and a control system module. The two-terminal M2LC subsystems are arranged into at least two output phase modules. A first one of the output phase modules defines a total value of inductance and includes a positive arm and a negative arm. The control system module is configured to apply selectively reassigned modulated switch functions to only one of the following at a given instance of time: the two-terminal M2LC subsystems of the positive arm of the first one of the output phase modules or the two-terminal M2LC subsystems of the negative arm of the first one of the output phase modules. The selective reassigning of the modulated switch functions forces charge balance of the individual capacitors of the series connected two-terminal M2LC subsystems at a predetermined rate.

Method for inhibiting a converter with distributed energy stores

A method for inhibiting a converter having at least two phase modules is disclosed. Each phase module has an upper and a lower valve branch, with each upper and lower valve branch having a plurality of two-pole submodules which are electrically connected in series and each have a unipolar energy storage capacitor, with a series connection of two turn-off semiconductor switches each being connected in parallel with an antiparallel connected diode. With the method, the submodules in an upper and a lower valve branch in each phase module in the converter are controlled to a switching state III, staggered in time. This considerably reduces the voltage load for the converter and a connected polyphase motor, or a connected power supply system.

Inverter and power converter having inverter mounted therein

Disclosed is an inverter having improved power conversion efficiency. The inverter ( 200 ) converts direct current power supplied from a plurality of direct current power supplies (V 1 , V 2 ) having different voltages into alternating current power. The inverter ( 200 ) is provided with a control unit ( 20 ). The control unit ( 20 ) generates modified sine waves using a power supply voltage (E 1 ) of the power supplied from the first direct current power supply (V 1 ), a power supply voltage (E 2 ) of the power supplied from the second direct current power supply (V 2 ), and a potential difference (E 1 −E 2 ) between the two power supply voltages. The control unit ( 20 ) generates the modified sine waves by controlling H bridge circuits provided for the direct current power supplies (V 1 , V 2 ), respectively.

Power converter system

A power converter system includes a first unipolar voltage source that produces a first voltage and a second unipolar voltage source that produces a second voltage. The power converter system also includes a transformer with a first primary winding, a second primary winding, and a secondary winding, and control equipment. The first primary winding is connected to the first unipolar voltage source, and the second primary winding is connected to the second unipolar voltage source such that when the first voltage is applied, a first secondary voltage is induced in the secondary winding and that when the second voltage is applied, a second secondary voltage is induced. The first secondary voltage is directed in opposition to the second secondary voltage. The control equipment drives the first unipolar voltage source and the second unipolar voltage source in alternation for the production of the first voltage and the second voltage.

Three-level power conversion apparatus

Wiring between semiconductor modules and a direct current power supply circuit, which construct a three-level power conversion apparatus, is made to be low inductance, so that reduction in size and cost can be attained easily. In cases where a connection is made between direct current power supplies (electrolytic capacitors) 25, 26 and IGBT modules 16 through 18 of a three-level inverter, a wiring conductor for a bi-directional switch part is divided into three conductors 35, 42, 43 or two conductors 35, 42 on a same surface, and these conductors are sandwiched by a P conductor 33 and an N conductor 37 , which are arranged at outer sides thereof, respectively, through insulating materials, so that a three-layer wiring structure of a sealed structure is formed. As a result of this, wiring inductance can be made small even with a small number of laminated layers, so that the reduction in size and cost of the apparatus as a whole is achieved.

Method for operating a converter circuit, and apparatus for carrying out the method

A method and apparatus are provided for operating a converter circuit, which includes n input phase connections and p output phase connections, where n≧2 and p≧2, and (n·p) two-pole switching cells for switching at least one positive and negative voltages between the poles. Power semiconductor switches of the switching cells are driven a drive signal. To reduce undesired circulating currents and adjust the mean voltage deviation of capacitive energy storage of all the switching cells to zero, an inductance is connected into each series connection, with a switching cell together with an inductance in each case forming a phase module. For each phase module, the drive signal is formed from a reference signal based on the voltage across the phase module and from a voltage signal across the inductance. The voltage signal is formed from an intermediate setpoint value of the current through the phase module.

3-level pulse width modulation inverter with snubber circuit

The present invention relates to a circuit arrangement which comprises at least one 3-level pulse width modulation inverter with a snubber circuit. The snubber circuit is formed by at least one coil (L), two capacitors (Cu, Co) and a series connection comprising four diodes (Dh 1 -Dh 4 ) poled in the same direction, whereof the two outer diodes (Dh 1 , Dh 4 ) are in each case directly connected to the input terminals ( 1, 3 ) for the positive and the negative pole of the input voltage. The electrical connection between the two inner diodes (Dh 2 , Dh 3 ) is connected on the one hand via the coil (L) to the input terminal ( 2 ) for the centre tap of the input voltage and on the other hand to the middle bridge branch of the pulse width modulation inverter. In one embodiment, the two capacitors (Cu, Co) are in each case connected with one terminal to the electrical connection between one of the inner diodes (Dh 2 , Dh 3 ) and one of the outer diodes (Dh 1 , Dh 4 ) and with the other terminal directly to the output terminal ( 4 ). With the proposed circuit, switching losses are completely avoided as a matter of principle with a simple and low-cost design.

Control of a modular converter having distributed energy stores with the aid of an observer for the currents and an estimating unit for the intermediate circuit energy

Methods and configurations controlling a converter having controllable power semiconductors, compare actual and target state values to obtain control difference values for a control unit producing setting voltage values. Control electronics provide control signals according to setting voltage values and transmit them to power semiconductors. The control unit generates voltage values so control difference values become small. Current and converter energy controls and energy balancing are performed jointly, actual state values are calculated by an observing unit based on setting voltage values considering measured current values and actual state intermediate-circuit energy values are calculated by an estimating unit considering measured intermediate-circuit energy values of positive and negative voltage sources. The observing and estimating units model the converter so actual state current and intermediate-circuit steady-state energy values correspond to error-free current and intermediate-circuit energy values. A periodic time-variant gain controller receives error-free values.

Converter Cell For Cascaded Converters And A Control System And Method For Operating A Converter Cell

A cascaded electric power converter and a method of operating a cascaded electric power converter are disclosed. The cascaded converter includes: a converter cell including a cell capacitor and at least one phase leg having at least two electric valves, the at least one phase leg being connected in parallel to the cell capacitor; and a control system for controlling the switching of the electric valves of the at least one phase leg. The control system is configured to, upon detection of a need to by-pass the converter cell, control the switching of the electric valves in a manner so that the cell capacitor is short circuited via a phase leg, so as to obtain a current surge through the phase leg, thereby creating a permanent current path through the converter cell.

Multi-Level DC/AC Converter

The multi-level DC/AC converter, comprising: an input () connectable to a direct voltage source (), with a first connection () and a second connection () between which can be applied an input voltage (Vi); a half-bridge with a first controlled switch () and a second controlled switch () between which is positioned an output (U) of the converter; a first connecting branch () between the first controlled switch () and the first connection () and a second connecting branch () between the second controlled switch () and the second connection (); a third controlled switch () associated to the first controlled switch (), connectable in series to the first controlled switch to generate an output voltage exceeding a first limit value (Vi/2); a fourth controlled switch () associated to the second controlled switch (), connectable in series to said second controlled switch to generate an output voltage below a second limit value (−Vi/2). 1. A multi-level DC/AC converter , comprising:an input connectable to a direct voltage source, with a first connection and a second connection between which an input voltage can be applied, a neutral being positioned between the first and the second connection;a half-bridge with a first controlled switch and a second controlled switch between which an output of the converter is positioned;a first connecting branch between the first controlled switch and said first connection and a second connecting branch between the second controlled switch and said second connection;a third controlled switch associated to said first controlled switch, connectable in series to said first controlled switch to generate an output voltage exceeding a first limit value;a fourth controlled switch associated to said second controlled switch, connectable in series to said second controlled switch to generate an output voltage below a second limit value;a first voltage regulator associated with said third controlled switch; anda second voltage regulator associated ...

Static var compensator with multilevel converter

A static synchronous compensator for use in reactive power compensation, the static synchronous compensator comprising at least one primary compensator limb including first and second DC terminals, and an AC terminal for connection in use to an AC network, the or each primary compensator limb defining first and second limb portions, each limb portion-including at least one switching element connected in series with a chain-link converter-between a respective one of the first and second DC terminate and the AC terminal, the switching elements of the first and second limb portions being operable to switch the respective chain-link converters in and out of circuit between the respective DC terminal and the AC terminal and the chain-link converters being operable to generate a voltage waveform at the AC terminal; and a secondary compensator limb including at least one DC link capacitor connected between the first and second DC terminals, the secondary compensator limb being connected in parallel with the or each primary compensator limb.

M2LC System and Method for Controlling Same

A modular multilevel converter system. The system includes a plurality of series connected two-terminal M2LC cells arranged into at least two output phase modules. A first one of the output phase modules has an inductance and an effective capacitance associated therewith. The first one of the output phase modules is configured so that a natural resonant frequency of the inductance with the effective capacitance of the first one of the output phase modules is greater than at least one of the following: an operating frequency of the first one of the output phase modules; a switching frequency of the first one of the output phase modules; and a switching frequency of any of the M2LC cells of the first one of the output phase modules.

Sub-module of a modular multi-stage converter

A sub-module for a modular multi-stage converter has an energy store and a power semiconductor series circuit connected in parallel to the energy store. In the semiconductor series circuit, two power semiconductor switches that can be activated and deactivated and have the same forward direction are connected in series. A free-wheeling diode is connected in parallel and in the opposite direction to each power semiconductor switch. A first connection terminal is connected to the energy store. A second connection terminal is connected to a potential point between the power semiconductor switches and to the free-wheeling diodes thereof. A bridging switch is disposed between the connection terminals for bridging the sub-module. The power semiconductors thereof are not destroyed upon closing the bridging switch and at least one connection terminal and/or a bridging branch that connects the two connection terminals to each other has an inductive component.

Multi-level converter, and inverter having the same and solar power supply apparatus having the same

There are provided a multi-level converter capable of outputting power having various voltage levels with respect to a single input power supply by using a simple circuit, an inverter having the same, and a solar power supply apparatus having the same. The multi-level converter includes a first buck-boost unit having a first power switch switching an input power supply and outputting a first power having a voltage level varied according to switching of the first power switch; a bypass unit outputting a second power having a voltage level of the input power supply; and a second buck-boost unit having a second power switch switching the input power supply and outputting a third power having a voltage level varied according to switching of the second power switch.

Valve current control method based on modular multi-level converter

The present invention relates to valve current control method based on modular multi-level converter, this method includes the control of the low frequency oscillations of the current and that of double frequency harmonic component; For said low frequency oscillations of the current, the control method includes some steps as below: first, calculate the half of the sum of the upper arm current and the lower arm current, it is the valve DC current component, said DC current component is arm circulating current; Secondly, comparing the actual value of the arm circulating current to setting value of that, the error is obtained, after some signal processing, additional output set voltage is obtained. For said the double frequency harmonic component of current, the control method includes some steps as below: firstly, figure out capacitor voltage fluctuation prediction value of the sub module; secondly, the output voltage is divided by the sum of the sub module reference voltage and the capacitor voltage fluctuation prediction value, and get the actual output set number of sub module. This method not only can realize stability of the dynamic performance of the system, but also can suppress the arm double frequency harmonic component, at the same time under the abnormal conditions of the AC system; the valve current has good output characteristics.

Multi-level converter, and inverter having the same and solar power supply apparatus having the same

There is provided a multi-level converter capable of a multi-level converter capable of outputting power having various voltage levels by using a simple circuit with respect to a single input power supply, an inverter having the same, and a solar power supply apparatus having the same. The present invention provides a multi-level converter including a first buck-boost unit having a single power switch switching an input power supply and outputting a first power having a voltage level varied according to the switching of the power switch, a bypass unit outputting a second power having a voltage level of the input power supply, and a second buck-boost unit sharing the power switch with the first buck-boost unit and outputting a third power having a voltage level varied according to the switching of the power switch; an inverter having the same; and a solar power supply apparatus having the same.

Modular converter cabinet system

A modular converter cabinet system of a converter having phase modules with upper and lower converter valves, wherein each converter valve has at least two converter cells and a branch inductor connected in series, includes a first valve cabinet, a second valve cabinet, and an inductor cabinet. The first and second valve cabinets each have several vertically spaced valve levels and several honeycomb cells arranged next to one another. The inductor cabinet has several vertically spaced phase levels. Two valve levels of at least one of the first and second valve cabinets are electrically connected to a respective phase level of the inductor cabinet that is arranged next to the at least one valve cabinet. A converter cabinet system which can be individually adapted to different converter output voltages in a simple manner is thus obtained.

Multilevel converter circuit

In some aspects of the invention, a number of semiconductor switches through which output current passes can be reduced between a direct current power source side, which is an input, and an alternating current output, thus achieving loss reduction, and enabling higher efficiency, price reduction, and miniaturization of a device. In some aspects, a direct current power source, formed of a series connection circuit of single power sources, which has three mutually different voltage levels including zero can be provided with first, second, third, and fourth arm pairs, each configured by connecting two arms formed of semiconductor switches in series, an alternating current switch configured by combining semiconductor switches. As such, a plurality of voltage levels can be to be selected from and output by an on and off control of these switch elements.

Power supply system

An operation mode selection unit selects an efficiency priority mode for minimizing the overall loss in a power supply system based on a load request voltage obtained in accordance with the condition of a load and on the conditions of DC power supplies, and generates a mode selection signal in accordance with the selection result. When SOC and/or output power have/has reached power supply restriction values in any DC power supply, an operation mode modification unit generates a final mode selection instructing signal so as to modify selection of the efficiency priority mode by the mode selection signal to select an operation mode in which power distribution between the DC power supplies can be controlled.

Modular multilevel converter using asymmetry

A power electronic converter assembly is provided having a multi-level converter, a plurality of phase elements and a controller to switch the multi-level converter. The multi-level converter includes a plurality of AC terminals and is operable to generate an AC phase voltage (V A , V B , V C ) at each AC terminal. The plurality of phase elements define a star connection in which a first end of each phase element is connected to a common junction. Each AC terminal is connected in series with a second end of a respective phase element of the star connection. The controller can switch the multi-level converter to modulate the plurality of AC phase voltages (V A , V B , V C ) to define a set of asymmetrical voltage vectors so as to synthesise a non-zero neutral point voltage at the common junction of the star connection, the non-zero neutral point voltage and each AC phase voltage (V A , V B , V C ) defining a line-to-neutral voltage across each phase element, the line-to-neutral voltages being equal in magnitude and displaced at equidistant phase angles.

PRE-CHARGING A MODULAR MULTILEVEL CONVERTER

A modular multilevel converter is for a high voltage testing source. The modular multilevel converter includes: an arm, the arm having a plurality of submodules coupled in series, wherein each of the submodules has a capacitor; and a control unit for controlling a pre-charging process of the capacitor of each of the submodules prior to a start of operation of the modular multilevel converter. The control unit is configured to: connect the arm to a constant voltage source for a first period of time; and, for a second period of time after the first period of time, feed a charging current to the arm and control the charging current at a predetermined constant reference current. 1. A modular multilevel converter for a high voltage testing source , the modular multilevel converter comprising:an arm, the arm comprising a plurality of submodules coupled in series, wherein each of the submodules comprises a capacitor; anda control unit for controlling a pre-charging process of the capacitor of each of the submodules prior to a start of operation of the modular multilevel converter, the control unit being configured to:connect the arm to a constant voltage source for a first period of time; and,for a second period of time after the first period of time, feed a charging current to the arm and control the charging current at a predetermined constant reference current.2. The modular multilevel converter according to claim 1 , wherein each of the submodules comprises a switching arrangement configured to insert claim 1 , bypass or block the respective one of the submodules.3. The modular multilevel converter according to claim 2 , wherein:the switching arrangement of each of the submodules comprises a first switching element and a second switching element; andthe switching elements and the respective capacitor of a respective submodule, of the submodules, are arranged according to a half-bridge topology.4. The modular multilevel converter according to claim 3 , wherein the ...

POWER CONVERSION DEVICE

A power converter includes an arm in which a plurality of converter cells are connected in series, each of the converter cells including at least two switching elements, a power storage element, and a pair of output terminals. A control device controls voltages of the plurality of converter cells by phase shift PWM control using a carrier signal for each converter cell. The converter cell includes a switch to have the converter cell bypassed. When the control device senses failure of the converter cell within the arm, it has a failed converter cell within the arm bypassed and rectifies uneven intervals among phases of carrier signals of a plurality of normal converter cells within the arm caused by failure of the converter cell. 2. (canceled)3. (canceled)4. The power conversion device according to claim 1 , wherein varies to delay the reference phase advanced relative to the reference phase of the carrier signal of the failed converter cell, among the reference phases of the carrier signals of the plurality of normal converter cells, and', 'varies to advance the reference phase delayed relative to the reference phase of the carrier signal of the failed converter cell, among the reference phases of the carrier signals of the plurality of normal converter cells., 'the carrier signal generator'}5. The power conversion device according to claim 1 , whereinthe carrier signal generator sets a minimum value of the amounts of variation in reference phases of the carrier signals of the plurality of normal converter cells to 0.6. The power conversion device according to claim 5 , whereinthe carrier signal generator does not vary the reference phase immediately following the reference phase of the carrier signal of the failed converter cell, among the reference phases of the carrier signals of the plurality of normal converter cells, but delays the reference phase other than the reference phase immediately following the reference phase of the carrier signal of the failed ...

POWER CONVERSION SYSTEM AND POWER CONVERSION DEVICE

A power conversion device includes: a power converter circuit which converts a direct-current power, output from a decentralized power supply, into an alternating-current power, and outputs the alternating-current power to a power distribution grid; a voltage target value generation unit which removes a high-frequency variation from a root mean square of a voltage detected by a voltage detection unit to generate a voltage target value; a correction unit which corrects the voltage target value when the correction unit detects that the automatic voltage regulator has performed an action; and a command unit which, if the voltage at the point of interconnection detected by the voltage detection unit deviates from a voltage control deadband referenced to the voltage target value, commands the power converter circuit to output a reactive power based on a magnitude of the deviated amount of voltage. 1. A power conversion system , comprising:an automatic voltage regulator installed in a power distribution grid; and the decentralized power supply system, including:', 'a decentralized power supply; and', 'a power conversion device,', 'the power conversion device including:', 'a power converter circuit to convert a direct-current power output from the decentralized power supply into an alternating-current power, and output the alternating-current power to the power distribution grid;', 'a voltage detection unit to detect a voltage at a point of interconnection between the power converter circuit and the power distribution grid;', 'a voltage target value generation unit to remove a high-frequency variation from a root mean square of the voltage detected by the voltage detection unit to generate a voltage target value;', 'a correction unit to correct the voltage target value when the automatic voltage regulator has performed an action; and', 'a command unit to command, when the voltage at the point of interconnection detected by the voltage detection unit deviates from a voltage ...

MODULAR MULTILEVEL CONVERTER LEG WITH FLAT-TOP PWM MODULATION, CONVERTER AND HYBRID CONVERTER TOPOLOGIES

A voltage source converter for interconnecting first and second electrical networks, including first and second terminals for connection to the first electrical network, and a primary converter limb extending between the first and second terminals including first and second primary limb portions separated by a third terminal connectable to the second electrical network. The converter further including a second chain-link converter connected to the third terminal and a control unit configured to selectively operate one or more chain-link modules to generate a discontinuous pulse width modulation voltage waveform. The converter further including a controller configured to selectively operate each chain-link converter to control the configuration of a discontinuous pulse width modulation voltage waveform at the third terminal. The controller including the control unit, and configured to selectively control switching of each primary limb portion into the circuit between the third terminal and one of the first and second terminals. 1. A voltage source converter , for interconnecting first and second electrical networks , comprising:first and second terminals for connection to the first electrical network; anda primary converter limb extending between the first and second terminals, the primary converter limb including first and second primary limb portions separated by a third terminal, the third terminal being connectable to the second electrical network, each primary limb portion including at least one switching element and/or a first chain-link converter, each primary limb portion being operable to be switched into and out of circuit between the third terminal and a respective one of the first and second terminals, each primary limb portion being operable to transfer power between the third terminal and a respective one of the first and second terminals;at least one second chain-link converter connected to the third terminal, the or each chain-link converter ...

Reducing Voltage Rating of Devices in a Multilevel Converter

A method for operating a multi-level converter is disclosed. A multi-level converter is provided with a plurality of switches connected in series and a flying capacitor connected to switch nodes of the plurality of switches, The switch nodes are biased initially to a fraction of an input voltage when the input voltage is initially applied to the plurality of switches. The flying capacitor is then precharged to a flying capacitor operating voltage. The multi-level converter is then operated after the flying capacitor is precharged by activating control signals to the plurality of switches. Diversion of precharge current by the plurality of switches may be performed while the flying capacitor is being precharged.

POWER CONVERTER

A power converter includes a full-bridge conversion circuit. The full-bridge conversion circuit includes a first leg and a second leg. The first leg includes at least two switches coupled to each other at a first node, and the second leg includes at least two switches coupled to each other at a second node. The power converter further includes an AC filter. The AC filter includes a first inductor, a second inductor and a capacitor. The first inductor includes a first end coupled to the first node and a second end could be couple to a grid. The second inductor includes a first end coupled to the second node and a second end could be couple to the grid. The capacitor includes a first end coupled to the second end of the first inductor and a second end coupled to the second leg. The first end of the capacitor is electrically coupled to the second end of the first inductor during a cycle of an AC voltage of the grid. 1. A power converter , comprising: a first leg comprising a first high side switch and a first low side switch coupled to each other at a first node, and', 'a second leg comprising a second high side switch and a second low side switch coupled to each other at a second node; and, 'a full-bridge conversion circuit comprising a first inductor comprising a first end coupled to the first node and a second end coupleable to a grid,', 'a second inductor comprising a first end coupled to the second node and a second end coupleable to the grid, and', 'a capacitor comprising a first end coupled to the second end of the first inductor and a second end coupled to the second leg,, 'an AC filer, comprisingwherein the first end of the capacitor is electrically coupled to the second end of the first inductor during a cycle of an AC voltage of the grid.2. The power converter of claim 1 , wherein the second high side switch and the second low side switch are configured to be turned off during a time window around a zero crossing of the AC voltage claim 1 , and wherein the ...

FLEXIBLE ALTERNATING CURRENT TRANSMISSION SYSTEM WITH MULTILEVEL INVERTER

A multilevel inverter includes an inner DC source group circuit that generates a plurality of voltage levels, and an outer DC source group circuit that generates a substantially sinusoidal output voltage. The substantially sinusoidal output voltage is generated using, at least in part, the plurality of voltage levels generated by the inner DC source group circuit. An H-bridge circuit supplies the substantially sinusoidal output voltage at alternating polarities to a load. 13-. (canceled)4. The flexible alternating current transmission system according to claim 20 , wherein a voltage level of the first DC voltage source of the outer source group equals the voltage level of the second DC voltage source of the outer source group.5. The flexible alternating current transmission system according to claim 4 , wherein a voltage level of at least one DC voltage source of the inner DC source group circuit is twice a voltage level of a DC voltage source of the outer DC source group circuit.6. The flexible alternating current transmission system according to claim 5 , wherein the first DC voltage source of the outer DC source group circuit is connected in opposite polarity to the second DC voltage source.7. The flexible alternating current transmission system according to claim 6 , wherein the H-bridge circuit includes four switching elements to supply the plurality of voltage levels in a substantially sinusoidal output voltage at alternating polarities to the load contacts.8. The flexible alternating current transmission system according to claim 7 , wherein alternate pairs of switching elements of the four switching elements of the H-bridge circuit are turned ON in order to generate the alternating polarities.911-. (canceled)12. The flexible alternating current transmission system according to claim 8 , wherein the control circuit is configured to control the switching elements of the inner DC source group circuit and the switching elements of the outer DC source group ...

DC-DC Conversion for Multi-Cell Batteries

A power supply has a multi-level DC-DC converter and a battery pack with two or more cells provided in series. The switching DC-DC converter provides a regulated voltage at an output. The converter has an energy storage element. The switching regulator is designed to selectively operate in two or more different modes. It switches between a first mode where one cell is connected (between battery and inductor of the converter), and the converter functions like a single cell buck converter and a second mode where two cells are connected in series and the converter functions like a two series cell buck converter. In general, any number of cells and modes can be provided, with successive cells being connected in series in each mode.

POWER CONVERSION SYSTEM AND POWER CONVERSION DEVICE

A bridge circuit converts input direct-current voltage and outputs alternating-current voltage. A filter circuit attenuates a high-frequency component of the alternating-current voltage output from the bridge circuit. A clamping circuit is disposed between the bridge circuit and the filter circuit, and is capable of short-circuiting the output side of the bridge circuit. A control circuit has a first mode in which a switching element causes the alternating-current voltage to be output to the filter circuit at three or more voltage levels, and a second mode in which the switching element causes the alternating-current voltage to be output to the filter circuit at two voltage levels. When power conversion devices have their alternating-current side output paths connected and operate in parallel, at least one of the power conversion devices operating in parallel operates in the second mode. 1. A power conversion system , comprising:a plurality of power conversion devices whose alternating-current side output paths are connected and that operate in parallel, a bridge circuit capable of converting input direct-current voltage and outputting alternating-current voltage;', 'a filter circuit that attenuates a high-frequency component of the alternating-current voltage output by the bridge circuit; and', 'a clamping circuit disposed between the bridge circuit and the filter circuit, and capable of short-circuiting an output side of the bridge circuit, and, 'wherein each of the plurality of power conversion devices includesamong the plurality of power conversion devices, the bridge circuit and the clamping circuit included in at least one power conversion device operate in a first mode in which the alternating-current voltage is output to the filter circuit at three or more voltage levels, and the bridge circuit and the clamping circuit included in each remaining power conversion device operate in a second mode in which the alternating-current voltage is output to the filter ...

Electrical Circuit with Auxiliary Voltage Source for Zero-Voltage Switching in DC-DC Converter Under All Load Conditions

An electrical circuit comprising an n-port m-phase active bridge converter with n≥2 and m≥1, where each port can be operated as an input or an output port, wherein each of the n ports has m phase legs with multiple active switches with parallel connected snubber or resonant capacitors, whereby the n ports can convert a DC-voltage into an AC voltage, the n ports connected via an m-phase transformer or over m separate transformers each connected to each of the m phase legs of each of the n ports to transfer power between the ports, wherein an auxiliary circuit is connected to the transformers to convert a part of a transformer input voltage and energy via an auxiliary voltage source into a DC mid-point capacitor of a DC-link of at least one of the n-port m-phase active bridge converters to recharge the DC mid-point capacitor.

POWER SUPPLY FOR SUBMODULE CONTROLLER OF MMC CONVERTER

A power supply for a submodule controller of an MMC converter, which supplies driving power to a submodule controller of an MMC connected to an HVDC system. The power supply includes: a bridge circuit unit including an energy storage unit storing a DC voltage of a series-connected submodule of the MMC converter, and multiple power semiconductor devices connected in parallel to the energy storage unit in a bridge form; a first resistor unit connected in parallel to the energy storage unit, and configured with at least one series-connected resistor; a second resistor unit connected in series to the first resistor unit; a switch unit connected in parallel to the first resistor unit; and a DC/DC converter converting a voltage output from output terminals formed in both ends of the second resistor unit into a low voltage, and supplying the same to the submodule controller. 1. A power supply for a submodule controller of an MMC converter , the power supply comprising:a bridge circuit unit including an energy storage unit storing a DC voltage of a series-connected submodule of the MMC converter, and multiple power semiconductor devices connected in parallel to the energy storage unit in a bridge form;a first resistor unit connected in parallel to the energy storage unit, and configured with at least one series-connected resistor;a second resistor unit connected in series to the first resistor unit;a switch unit connected in parallel to the first resistor unit; anda DC/DC converter converting a voltage output from output terminals formed in both ends of the second resistor unit into a low voltage, and supplying the same to the submodule controller.2. The power supply of claim 1 , wherein when a voltage detected in the energy storage unit is equal to or smaller than a preset voltage claim 1 , the switch unit is turned on so as to form a bypass circuit in the first resistor unit.3. A power supply for a submodule controller of an MMC converter claim 1 , the power supply ...

GROUNDING ARRANGEMENT FOR A VOLTAGE SOURCE CONVERTER

A grounding arrangement for a Voltage Source Converter (VSC) in a power transmission system is provided. The VSC comprises at least one converter branch () comprising at least one module (-), each module comprising a plurality of serially connected sub-modules (-) that can be controllably switched to generate a controlled voltage across the module (-) and each module including a first sub- module (24) at one end thereof and a last sub-module () at an opposite end thereof. Each sub-module (-) includes a first terminal (), a second terminal (), an energy storage element () and a switching arrangement (), wherein at least one of the first () or second terminals () is coupled to a terminal of the energy storage unit (). A first terminal () of the first sub-module () of a module () at one end of the converter branch () is configured to be connected to earth potential on or after shutdown of the converter, and a second terminal () of the last sub-module () of the module (N) at the opposite end of the converter branch () is configured to be connected to earth potential on or after shutdown of the converter. A grounding arrangement () comprising a plurality of switch units (42) is provided, each switch unit () associated with one of the plurality of sub-modules (-) of each module (22-22) and configured to connect the first () and second () terminals of the associated sub-module (24-24) on remote activation of the grounding arrangement (), following connection to earth potential of the first () and last sub-modules () of the converter branch (). 117-. (canceled)18. A voltage source converter (VSC) for use in a power transmission system , the VSC comprising:at least one converter branch comprising at least one module, each module comprising a plurality of serially connected sub-modules that can be controllably switched to generate a controlled voltage across the module and each module including a first sub-module at one end thereof and a last sub-module at an opposite end ...

Power conversion apparatus and electrical-mechanical energy conversion system

A power conversion apparatus includes arms in each of which one or more unit converters each including a capacitor and capable of outputting an arbitrary voltage are connected in series, and a point P as a first node to which one end of the respective arms are Y-connected, and a point N as a second node to which a neutral terminal of the rotary electric machine is connected. The other end of the respective arms are connected to one ends of respective phase windings of a rotary electric machine.

POWER DEVICE WITH ELECTROLYTIC CAPACITORS

An Uninterruptible Power Supply (UPS) system is provided which includes an input configured to receive input power, an output configured to provide output power to a load, power conversion circuitry coupled to the input and the output, a capacitor coupled to the power conversion circuitry, and a controller coupled to the power conversion circuitry. The controller is configured to determine a first value indicative of an equivalent series resistance of the capacitor, determine, based on the first value, if the capacitor satisfies at least one criterion, and execute, responsive to determining that the relative value satisfies the at least one criterion, one or more actions to address degradation of the capacitor. 1. An Uninterruptible Power Supply (UPS) system , the UPS system comprising:an input configured to receive input power;an output configured to provide output power to a load;power conversion circuitry coupled to the input and the output;a capacitor coupled to the power conversion circuitry; and determine a first value indicative of an equivalent series resistance of the capacitor;', 'determine, based on the first value, if the capacitor satisfies at least one criterion; and', 'execute, responsive to determining that the relative value satisfies the at least one criterion, one or more actions to address degradation of the capacitor., 'a controller coupled to the power conversion circuitry, the controller configured to2. The UPS system of claim 1 , further comprising a filter coupled in parallel with the capacitor.3. The UPS system of claim 2 , wherein the controller is configured to determine a second value indicative of a voltage across the filter claim 2 , and determine at least one third value indicative of at least one current through the power conversion circuitry.4. The UPS system of claim 3 , wherein the controller is configured to determine the first value indicative of the equivalent series resistance of the capacitor based on the second value ...

Power conversion device

A power conversion device in which a plurality of converter cells are connected in series with one another. The converter cells each include two or more semiconductor devices, an energy storage element and a bypass element including a constituent element for setting the bypass element to be close-circuited by detecting abnormality of a converter cell, and including a constituent element for controlling, among the semiconductor devices, a semiconductor device connected in parallel with the bypass element to set in a turn-on state, at the same time when the bypass element is set close-circuited or in advance of its close circuit.

FIVE-LEVEL CONVERTING DEVICE

A five-level converting device includes an AC terminal, a bus capacitor module having a positive terminal, a negative terminal and a neutral terminal, a first switch module and a second switch module. The first switch module includes a bidirectional switching circuit, and the bidirectional switching circuit includes two first switching units reversely connected in series. The second switch module includes two second switching units, two third switching units, two fourth switching units, and two fifth switching units. The two second switching units are cascaded and connected to the two fourth switching units in parallel. The third, the fourth and the fifth switching units are cascaded and are connected to the bus capacitor module in parallel. Two different connection points of the first switch module are connected to the third switching units and fifth switching units through two flying capacitor modules respectively. 1. A five-level converting device , comprising:an AC terminal;a bus capacitor module, having a positive terminal, a negative terminal and a neutral terminal;a first switch module, having a bidirectional switching circuit, wherein the bidirectional switching circuit comprises two first switching units reversely connected in series, a terminal of one of the two first switching units connects to the neutral terminal of the bus capacitor module;a second switch module, having two second switching units, two third switching units, two fourth switching units and two fifth switching units, wherein the two second switching unit are cascaded to each other, the two third switching units, the two fourth switching units and the two fifth switching units are cascaded and are connected to the bus capacitor module in parallel, wherein the two third switching units are connected to the positive terminal of the bus capacitor module, the two fifth switching units are connected to the negative terminal of the bus capacitor module, the two fourth switching units and the two ...

VOLTAGE SOURCE CONVERTER

A voltage source converter includes DC terminals for connection to a DC network, a plurality of converter limbs between the DC terminals, and a controller. Each converter limb includes first and second limb portions separated by a respective AC terminal, the AC terminal of each converter limb connecting to a multi-phase AC network. Each limb portion extends between a corresponding DC terminal and AC terminal. Each limb portion including a valve having switching element(s) and energy storage device(s), the switching element being switchable to selectively insert the energy storage device into the limb portion and bypass the energy storage device to control a voltage across that valve. The controller is programmed to control the switching of valves to form a current circulation path including the limb portions corresponding to the selected valves, the AC phases connected to the limb portions corresponding to the selected valves, and the DC network. 1. A voltage source converter comprising:first and second DC terminals for connection to a DC network; anda plurality of converter limbs, each converter limb extending between the first and second DC terminals, each converter limb including first and second limb portions separated by a respective AC terminal, the AC terminal of each converter limb for connection to a respective AC phase of a multi-phase AC network, each first limb portion extending between the corresponding first DC terminal and AC terminal, each second limb portion extending between the corresponding second DC terminal and AC terminal, each limb portion including a respective valve, each valve including at least one switching element and at least one energy storage device, the or each switching element of each valve being switchable to selectively insert the or each corresponding energy storage device into the corresponding limb portion and bypass the or each corresponding energy storage device in order to control a voltage across that valve; anda ...

Hybrid Transformer Systems and Methods

Embodiments of the present disclosure can include a hybrid transformer system comprising an electrical voltage transformer comprising: a high-voltage winding, the high-voltage winding comprising a first end and a second end, the first end having a lower voltage than the second end; a plurality of taps disposed proximate the first end of the high-voltage winding; a multi-level converter coupleable to the plurality of taps of the electrical voltage transformer, the multi-level converter configured to simultaneously control voltage injection and VAR injection to the high-voltage winding of the electrical voltage transformer; and a controller electrically coupleable to the multi-level converter, such that when the multi-level converter is coupled to the plurality of taps of the electrical voltage transformer, the controller is configured to selectively inject at least one of VARs or voltage to the high-voltage winding of the electrical voltage transformer.

Multilevel Converter

A multilevel converter for performing a DC to AC or an AC to DC voltage conversion as provided. The multilevel converter has a first DC terminal and a second DC terminal, a first converter arm and a second converter arm, wherein each converter arm comprises at least one converter cell, at least one AC terminal and an electric component. The first converter arm, the electric component and the second converter arm are connected in series between the first DC terminal and the second DC terminal. The electric component is connected between the first converter arm and the second converter arm.

FLYING CAPACITOR CIRCUIT, CIRCUIT MODULE AND POWER CONVERSION APPARATUS

If current path is switched via switching, voltage overshoot exceeding the device breakdown voltage may be generated. A flying capacitor circuit is provided, having a plurality of switching devices cascade-connected on a first surface of a substrate; a plurality of rectifier devices cascade-connected on a second surface of the substrate; and at least one capacitor provided in a wiring connecting main terminals of a switching device and a rectifier device that are associated with each other and included in the plurality of switching devices and the plurality of rectifier devices; and at least part of the wiring runs sandwiching the substrate in parallel. 1. A flying capacitor circuit comprising:a plurality of switching devices cascade-connected on a first surface of a substrate;a plurality of rectifier devices cascade-connected on a second surface of the substrate; andat least one capacitor provided in a wiring connecting main terminals of a switching device and a rectifier device that are associated with each other and included in the plurality of switching devices and the plurality of rectifier devices; whereinat least part of the wiring runs sandwiching the substrate in parallel.2. The flying capacitor circuit according to claim 1 , wherein the plurality of switching devices are cascade-connected in a straight line and the plurality of rectifier devices are cascade-connected in a straight line parallel to the line in which the plurality of switching devices are cascade-connected.3. The flying capacitor circuit according to claim 1 , wherein the plurality of switching devices are cascade-connected in a straight line and the plurality of rectifier devices are cascade-connected in a straight line which is the same straight line in a planar view as the line in which the switching devices are cascade-connected.4. The flying capacitor circuit according to claim 1 , wherein the at least one capacitor is included in each of a plurality of wirings except a wiring ...

VOLTAGE SOURCE CONVERTER APPARATUS

This application relates to a cell () or sub-module for a voltage source converter (). The cell includes an energy storage apparatus () and a plurality of dual-switch semiconductor packages (), each having first and second semiconductor switches () connected in series. The cell is operable in an active state in which an energy storage apparatus () is electrically connected in series between cell terminals () and a bypass state in the cell terminals () are electrically connected via a path that bypasses the first energy storage apparatus. The plurality of dual-switch semiconductor switch packages are configured to provide a first set of semiconductor switches () connected between nodes of the cell that are electrically connected in the first active state and electrically disconnected in the first bypass state; and a second set of semiconductor switches () is connected between nodes of the cell that are electrically disconnected in the first active state and electrically connected in the bypass state. The second set of switches comprises a greater number of switches in parallel than the first set of switches. 115-. (canceled)16. A cell for a voltage source converter , comprising:first and second cell terminals;a first energy storage apparatus; anda plurality of dual-switch semiconductor packages, each dual-switch semiconductor package comprising first and second semiconductor switches electrically connected in series between a first package terminal and a second package terminal and a third package terminal electrically connected to a node between the first and second semiconductor switches;wherein, the plurality of dual-switch semiconductor switch packages are configured so as to be operable in a first active state in which the first energy storage apparatus is electrically connected in series between the first and second cell terminals and a bypass state in the first and second cell terminals are electrically connected via a path that bypasses the first energy ...

LOW-VOLT DECOUPLING FROM A MODULAR ENERGY STORE CONVERTER SYSTEM

The invention discloses a module energy store converter system () comprising the following: at least one converter arm () comprising a plurality of standard modules () connected in series, and at least one extra-low voltage module (ELV module) (), wherein the standard modules () and the ELV module can be connected such that inputs () of a transducer () of the ELV module can be optionally connected to the storage element () of an adjacent standard module () serially and/or anti-serially, or the transducer () can be decoupled from the storage element (), and/or the inputs () of the transducer () can be optionally connected to the storage element of an adjacent standard module () in parallel, or the transducer () can be decoupled from the storage element (). 1. Modular energy store converter system , comprising:at least one converter arm, which comprises a plurality of standard modules connected in series, at least one first terminal and at least one second terminal,', 'a storage element for electrical energy, in particular a battery, or an energy conversion element, and', 'a plurality of switches,, 'wherein each of the standard modules comprises'}wherein in each of two adjacent standard modules from the standard modules, the at least one first terminal of one standard module of the two adjacent standard modules is connected either directly or via an intermediate component to the at least one second terminal of the other standard module of the two adjacent standard modules, and is configured to receive information regarding a current charge state of the storage elements or voltage or output power of the energy conversion elements, and', 'which is suitable for actuating at least a part of the plurality of switches depending on the current charge state of the storage elements a current output power or voltage of the energy conversion elements in an energy supply mode or energy consumption mode, in such a way that the converter arm as a whole supplies a desired voltage or ...

METHOD AND DEVICE FOR DAMPING OF LCL FILTER DURING START-UP OF AN ELECTRONIC APPLIANCE

The present invention relates to an electronic appliance, in particular a low harmonic drive, an active rectifier, a grid converter and/or any active front end or grid converter with an LCL filter. The converter may be a two-level, a three-level or a multilevel inverter. The electronic appliance includes an LCL filter on its grid side and an active front end rectifier provided on its load side. The LCL filter includes grid side inductors and the active front end rectifier is connected to the LCL filter. The present invention also relates to a method for damping a corresponding electronic appliance. 1. An electronic appliance , in particular a low harmonic drive , an active rectifier , a grid converter and/or any active front end or grid converter with an LCL filter , wherein the converter may be a two-level , a three-level or a multilevel inverter , comprising an LCL filter on its grid side and an active front end rectifier (AFE) on its load side , wherein the LCL filter comprises grid side inductors and the active front end rectifier (AFE) is connected to the LCL filter , wherein damping components are provided in parallel to the grid side inductors wherein the damping components are connectable to the grid side ends of the grid side inductors via switches.2. The electronic appliance according to claim 1 , wherein the damping components comprise damping resistors claim 1 , secondary windings with a switch and/or the modification of a magnetic core with a switch.4. The electronic appliance according to claim 1 , wherein the damping components are only connected to the grid side ends of the grid side inductors when the electronic appliance is connected to the grid via grid switches and the active front end rectifier (AFE) is not modulating.5. The electronic appliance according to claim 1 , wherein the damping components are disconnected from the grid side ends of the grid side inductors as soon as the active front end rectifier (AFE) has synchronized to the grid.6. ...

POWER CONVERSION DEVICE

A power conversion device converts power between a direct-current (DC) circuit and an alternating-current (AC) circuit. The power conversion device includes a power converter circuit which includes a plurality of unit converters connected in series, and a controller. The unit converter includes one or more switching elements and a capacitor. The controller transmits, to the unit converter through a first transmission medium, information on a switching command for the unit converter. The unit converter transmits, to the controller through a second transmission medium, information on at least one condition of the unit converter. The first transmission medium is an optical fiber, and the second transmission medium is a wireless communication channel. 1. A power conversion device for converting power between a direct-current (DC) circuit and an alternating-current (AC) circuit , the power conversion device comprising:a power converter circuit which includes a plurality of unit converters connected in series; anda controller, whereineach unit converter of the plurality of unit converters includes one or more switching elements and a capacitor,the controller transmits, to the unit converter through a first transmission medium, information on a switching command for the unit converter,the unit converter transmits, to the controller through a second transmission medium, information on at least one condition of the unit converter, andthe first transmission medium is an optical fiber, and the second transmission medium is a wireless communication channel.2. The power conversion device according to claim 1 , whereinthe controller transmits, to the unit converter through the first transmission medium and the second transmission medium, information on communications abnormality or abnormality in the controller.3. The power conversion device according to claim 1 , whereinthe unit converter transmits, to the controller through the first transmission medium and the second ...

POWER CONVERTER

A power converter includes a neutral point clamped inverter circuit including a first capacitor and a second capacitor that are connected in series to divide an input direct-current voltage by half. When receiving an instruction to start a single-phase three-wire output control process and finding that a voltage difference between a voltage across the first capacitor and a voltage across the second capacitor exceeds a predetermined threshold, the controller performs a capacitor voltage balancing process for reducing the voltage difference before starting the single-phase three-wire output control process. 1. A power converter , comprising:a neutral point clamped inverter circuit including a first capacitor and a second capacitor that are connected in series to divide an input DC voltage by half, a plurality of switching elements, and first to third output terminals; anda controller configured to perform a single-phase three-wire output control process to cause the inverter circuit to output a first AC voltage from between the first output terminal and the second output terminal and to output a second AC voltage having an inverted polarity from the first AC voltage from between the third output terminal and the second output terminal,wherein when receiving an instruction to start the single-phase three-wire output control process and finding that a voltage difference between a voltage across the first capacitor and a voltage across the second capacitor exceeds a predetermined threshold, the controller performs a capacitor voltage balancing process for reducing the voltage difference before starting the single-phase three-wire output control process.2. The power converter according to claim 1 , wherein claim 1 ,when the voltage difference is less than or equal to the predetermined threshold, the controller starts the single-phase three-wire output control process without performing the capacitor voltage balancing process.3. The power converter according to claim 1 , ...

Methods and apparatus for controlling power switches via a digital communication bus

Methods and apparatus are provided that can be used to control a set of power switches operating as a power converter. The method comprises providing a set of power switches and at least one switch driver, each power switch being operable to connect and disconnect one of a set of input power line to an output power line, each switch driver setting the state(s) of an associated power switch or switches; generating by a controller a set of switch commands, each command indicating a desired state of a respective one of said power switches at a moment in time; sending each switch command from the controller to a driver module containing the switch driver associated with the respective power switch; receiving at each driver module switch commands for its associated power switch(es) and causing each switch driver to set the state(s) of the appropriate power switch(es) accordingly; wherein the step of sending said switch commands comprises multiplexing commands for at least a subset of said switches into a series of multi-bit command frames and transmitting said command frames on a serial communication channel, and wherein the step of receiving said switch commands comprises receiving said multi-bit command frames from said communication channel and extracting individual switch commands therefrom. The method and apparatus can be used for example in a UPS system.

QUASI FIVE-LEVEL INVERTER

According to one aspect, embodiments of the invention provide an inverter comprising an input, an output, a plurality of DC busses, a mid-point bus, an LC filter, a common node coupled to the LC filter, a plurality of switches coupled to the plurality of DC busses and the common node, a bidirectional switch coupled between the mid-point bus and the common node, and a controller configured to operate the plurality of switches and the bidirectional switch in a first mode of operation to generate a voltage at the common node at a first positive DC voltage level, in a second mode of operation to generate the voltage at a second positive DC voltage level, in a third mode of operation to generate the voltage at a first negative DC voltage level, and in a fourth mode of operation to generate the voltage at a second negative DC voltage level. 1. An inverter comprising:an input configured to be coupled to a DC source and to receive input DC power from the DC source;an output configured to be coupled to a load and to provide output AC power to the load;a plurality of DC busses coupled to the input and configured to receive the input DC power from the DC source;a mid-point bus coupled to the input and to the plurality of DC busses;an LC filter coupled to the output;a common node coupled to the LC filter;a plurality of switches coupled to the plurality of DC busses and the common node;a bidirectional switch coupled between the mid-point bus and the common node; anda controller configured to operate the plurality of switches and the bidirectional switch in a first mode of operation to generate a voltage at the common node at a first positive DC voltage level, to operate the plurality of switches and the bidirectional switch in a second mode of operation to generate the voltage at the common node at a second positive DC voltage level, to operate the plurality of switches and the bidirectional switch in a third mode of operation to generate the voltage at the common node at a ...

Power Control System and Control Device

A power control system includes: a first AC/DC converter; a second AC/DC converter; a first switch connected between a first transmission line of a first power system having a first system frequency and the first AC/DC converter; a second switch connected between the first transmission line and the second AC/DC converter; a third switch connected between a second transmission line of a second power system having a second system frequency and the first AC/DC converter; a fourth switch connected between the second transmission line and the second AC/DC converter; a fifth switch connected between the first AC/DC converter and the second AC/DC converter; and a control device. When the first and second AC/DC converters are caused to operate as AC/DC converters in a BTB (Back to Back) method, the control device controls at least the fifth switch to be in a closed state.

Control device and power control system

A control device for controlling a power source connected to an alternating-current (AC) power system includes: a frequency control unit that controls a frequency of the power source operating in a constant-voltage constant-frequency control scheme; a power calculation unit that calculates, when the frequency control unit varies a frequency of the power source, a variation of an effective power output from the power source; an arithmetic unit that calculates a frequency characteristics constant of the AC power system, based on a variation of the frequency of the power source and the variation of the effective power output from the power source; and a selection unit that selects a control scheme for the power source, based on the frequency characteristics constant of the AC power system.

Multi-Module DC-to-DC Power Transformation System

A transformation system capable of efficiently transforming electrical power from one dc voltage to a second dc voltage or of regulating power flow within a network of constant nominal voltage; in each case without intermediate magnetic transformation. The transformation system is based on periodic and resonant delivery of charge from the first of two dc nodes to a system of capacitors, electrical reconfiguration of those capacitors, then delivery of power to a second dc node.

Power supply system

A power supply system includes: a load; a power line connected to the load; first and second DC power supplies being capable of supplying electric power to the load; a power converter connected between the first and second DC power supplies and the power line; and a controller for controlling an operation of the power converter. When shifting of the first operating mode employing only one of the first and second power supplies to the second operating mode employing both the first and second power supplies is started, the controller sets input and output power command values for other of the first and second DC power supplies to be equal to or higher than a lower limit value, and maintains, within a predetermined range, a ratio of the input and output power command values for the first and second DC power supplies, relative to the power demanded by the load.

Black start of a multilevel voltage source converter

A voltage source converter includes a black start control unit and cells, where each cell includes a first switch between a first end of a cell capacitor and a first cell terminal, a second switch between a second end of the cell capacitor and the first cell terminal, where a second cell terminal is provided via the first or the second end of the cell capacitor, a first power supply unit and a second power supply unit, where the black start control unit is configured to perform, after the initial application of a DC voltage to a cell terminal of a cell and the subsequent initial charging of the chargeable power supply unit of one of the switches, charging of an uncharged power supply unit of the other switch through repeatedly turning on and off the switch with initially charged power supply unit.

Power converters for aircraft starter/generators

A method of converting power includes receiving alternating current (AC) at the first phase leg set of a power conversion system having first and second phase legs sets connected by direct current (DC) leads. The first phase leg set rectifies the received AC power into DC power by switching outer switches of the first phase leg set into an off state. The DC lead conveys the DC power from the first phase leg set to the second phase leg set. The second phase leg set inverts the DC power into AC power.

POWER-OVER-ETHERNET POWERED INVERTER

An apparatus may include a data management assembly and a DC to AC inverter assembly. The data management assembly may include a data input, a data output, and a power port. The data management assembly may be configured to receive in combination a data signal and a variable DC input voltage on the data input, separate the received data signal from the input voltage, output the data signal on the data output, and output the input voltage on the power port. The DC to AC inverter assembly may be configured to receive the input voltage from the power port, boost the input voltage to a predetermined DC stepped-up voltage that is constant for different input voltages, convert the stepped-up voltage to an AC voltage, and output the AC voltage on a power output. 1. An apparatus comprising:an data management assembly including a data input, a data output, and a power port, the data management assembly being configured to receive in combination a data signal and a variable DC input voltage on the data input, separate the received data signal from the input voltage, output the data signal on the data output, and output the input voltage on the power port; anda DC to AC inverter assembly configured to receive the input voltage from the power port, boost the input voltage to a predetermined DC stepped-up voltage that is constant for different input voltages, convert the stepped-up voltage to an AC voltage, and output the AC voltage on a power output.2. The apparatus of claim 1 , wherein the DC to AC inverter assembly includes a boost converter and a controller circuit claim 1 , the boost converter being configured to step the input voltage up to a stepped-up voltage determined by a voltage-control signal claim 1 , and the controller circuit being responsive to an input-voltage signal representative of the input voltage to produce the voltage-control signal appropriate to cause the boost converter to step up the input voltage to the predetermined DC stepped-up voltage.3. The ...

Modular dc-dc converter

A modular dc-dc boost converter system is provided that can substantially improve efficiency over a wide range of input and output voltages. The system includes three modules: a buck module, a boost module, and a dc transformer module. These modules are interconnected such that the system output voltage is equal to the sum of the output voltages of adc-dc converter module and a dc transformer module. Depending on the operating point, one or more modules may operate in passthrough mode, leading to substantially reduced ac losses. The required capacitor size and the transistor voltage ratings are also substantially reduced, relative to a conventional single dc-dc boost converter operating at the same input and output voltages.

Method And Controller For Protecting A Voltage Source Converter

A method in a controller for protection of a voltage source converter including one or more phases, each phase including one or more series-connected converter cells. Each converter cell has a by-pass switch for enabling by-pass thereof. The method includes the steps of detecting an over-voltage condition, and controlling simultaneously the by-pass switches of each converter cell, so as to bypass the converter cells upon detection of such over-voltage condition. The invention also encompasses a controller, computer programs and computer program products.

Operating method for an inverter and grid fault tolerant inverter

The disclosure relates to a method for operating an inverter that includes at least one bridge assembly that is actuated in a modulated manner for supplying electrical power to an energy supply network. Initially, the inverter is operated by the unipolar actuation of the at least one bridge assembly and the energy supply network is monitored for the presence of a network fault. If a network fault is detected, the inverter is operated at least at intervals by the bipolar actuation of the at least one bridge assembly. The disclosure further relates to a network fault-tolerant inverter which is equipped for carrying out the method.

Buck Boost Converter Cell for MMC

The present disclosure relates to a converter cell () for an MMC. The cell comprises a primary energy storage (C), an inductor (Lf), and a secondary energy storage (C); and first and second converter valves (T, T). The secondary energy storage (C) is connected in series with the first converter valve (T1), and together with said first converter valve in parallel with the inductor (L), and the primary energy storage (C) is connected in series with the second converter valve (T), and together with said second converter valve (T) in parallel with the inductor (L). 110.-. (canceled)11. A converter cell for a modular multilevel converter , the cell consisting of:a primary energy storage;an inductor;a secondary energy storage, the primary energy storage, the inductor and the secondary energy storage all connected in parallel with each other between two terminals of the cell;a first converter valve comprising a first semiconductor switch and a first antiparallel diode, wherein the secondary energy storage is connected in series with the first converter valve, and together with the first converter valve in parallel with the inductor; anda second converter valve comprising a second semiconductor switch and a second antiparallel diode, the second semiconductor switch able to conduct electrical current in the same direction as the first semiconductor switch when switched to a conducting state, wherein the primary energy storage is connected in series with the second converter valve, and together with the second converter valve in parallel with the inductor; when the first semiconductor switch is switched to conducting and the second semiconductor switch is switched to non-conducting, a current is allowed to flow from the secondary energy storage to the inductor, charging the inductor, via the first semiconductor switch, after which;', 'when both the first semiconductor switch and the second semiconductor switch are switched to non-conducting, a current is allowed to flow from ...

FLYING CAPACITOR (FC)-TYPE 3-LEVEL POWER CONVERSION DEVICE

An FC-type 3-level power conversion device turns on or off first to fourth semiconductor switching elements based on comparison between a flying capacitor voltage and a half of higher-voltage side filter capacitor voltage, comparison between the higher-voltage side filter capacitor voltage and the flying capacitor voltage plus a lower-voltage side filter capacitor voltage, comparison between the flying capacitor voltage and the lower-voltage side filter capacitor voltage, and comparison between the lower-voltage side filter capacitor voltage or the higher-voltage side filter capacitor voltage and a filter capacitor voltage command value, so that an electric current flows along a path including a filter reactor L and charging a flying capacitor so as to charge a lower-voltage side filter capacitor or a higher-voltage side filter capacitor to predetermined values. 1. An FC-type three-level power conversion device comprising:a higher voltage side filter capacitor;first to fourth semiconductor switching elements connected in series between a positive electrode and a negative electrode of the higher voltage side filter capacitor, and arranged in this order from the positive electrode to the negative electrode;a flying capacitor connected between a node between the first and second semiconductor switching elements and a node between the third and fourth semiconductor switching elements;a filter reactor including a first end connected to a node between the second and third semiconductor switching elements;a lower voltage side filter capacitor connected between the negative electrode of the higher voltage side filter capacitor and a second end of the filter reactor opposite to the first end; anda direct current voltage source connected in parallel with the higher voltage side filter capacitor or the lower voltage side filter capacitor;wherein the first to fourth semiconductor switching elements are configured to be turned on and off so as to cause an electric current to ...

MULTI-LEVEL CIRCUIT, THREE-PHASE MULTI-LEVEL CIRCUIT, AND CONTROL METHOD

A multi-level circuit, a three-phase multi-level circuit, and a control method are provided. The multi-level circuit includes two groups of bus capacitors that are connected in series. The circuit further includes a plurality of switching transistor branches that are connected in parallel to the capacitors, where each switching transistor branch includes a first half bridge and a second half bridge, and a common terminal of the two half bridges is grounded. Furthermore, the circuit includes two coupled inductors, where each input terminal of each coupled inductor is connected to a common terminal of two switching transistors in the first half bridge in the switching transistor branches. In this circuit, a quantity of groups of bus capacitors is decreased and circuit design complexity is reduced. Further, a dropout voltage of the switching transistors is reduced. 1. A multi-level circuit , comprising:a capacitance branch comprising a first capacitor and a second capacitor that are connected in series, wherein a common terminal of the first capacitor and the second capacitor is grounded;at least two switching transistor branches that are connected in parallel to the capacitance branch, wherein each switching transistor branch comprises a first half bridge and a second half bridge, and a common terminal of the first half bridge and the second half bridge of each switching transistor branch is grounded; anda first coupled inductor and a second coupled inductor, wherein an input terminal of the first coupled inductor is connected to a common terminal of two switching transistors in the first half bridge in the switching transistor branches; and an input terminal of the second coupled inductor is connected to a common terminal of two switching transistors in the second half bridge of the switching transistor branches.2. The multi-level circuit according to claim 1 , wherein a third half bridge and a fourth half bridge are separately connected between an output terminal of ...

Power Converter and Power Conversion System

A power converter that performs power conversion between a DC line and an AC system includes a power conversion circuit including a plurality of submodules connected in series with each other, and a controller to control each of the plurality of submodules. Each submodule includes a switching circuit and a capacitor connected in parallel with the switching circuit. When a circuit breaker provided between the AC system and the power conversion circuit is opened, the controller drives the switching circuit of at least one submodule of the plurality of submodules such that the capacitor of the at least one submodule is discharged via a discharge circuit connected to the DC line. 1. A power converter that performs power conversion between a DC line and an AC system , the power converter comprising:a power conversion circuit including a plurality of submodules connected in series with each other; anda controller to control each of the plurality of submodules, whereineach of the plurality of submodules includes a switching circuit and a capacitor connected in parallel with the switching circuit, andwhen a circuit breaker provided between the AC system and the power conversion circuit is opened, the controller drives the switching circuit of at least one submodule of the plurality of submodules such that the capacitor of the at least one submodule is discharged via a discharge circuit connected to the DC line,wherein the switching circuit includes a switching element and a thyristor connected in parallel with the switching element, andthe controller drives the thyristor of the at least one submodule to discharge the capacitor of the at least one submodule via the discharge circuit.2. The power converter according to claim 1 , wherein the controller sets a number of the at least one submodule such that a sum of output voltages of the respective submodules is less than a threshold.3. The power converter according to claim 1 , wherein the controller sets a number of the at ...

OPERATING A MULTILEVEL CONVERTER

A method of operating a multilevel converter having multiple phase modules, each with three phase module branches. In a first switching position, a switching device of each phase module connects an alternating voltage connection of the phase module to a first connection point between a first phase module branch and a third phase module branch. In a second switching position, the switching device connects the alternating voltage connection to a second connection point between the third phase module branch and a second phase module branch. In the method, circulating currents of the multilevel converter are controlled in accordance with total energy variables and differential energy variables of the phase modules to balance the energy between the phase module branches. 110-. (canceled)11. A method of operating a multilevel converter , the method comprising:providing the multilevel converter with a plurality of phase modules that are connected in parallel with one another between a first DC voltage connection and a second DC voltage connection of the multilevel converter,each of the phase modules having a plurality of modules each with at least two electronic switching elements and an electrical energy storage device;each of the phase modules having a first phase module branch, which is connected to the first DC voltage connection, a second phase module branch, which is connected to the second DC voltage connection, a third phase module branch, which connects the first phase module branch with the second phase module branch, and a switching device having a first switching position that connects an AC voltage connection of the phase module to a first connecting point between the first phase module branch and the third phase module branch and a second switching position that connects the AC voltage connection to a second connecting point between the third phase module branch and the second phase module branch;and the method further comprising:determining for each of the ...

Three-level converter using an auxiliary switched capacitor circuit

In a described example, an apparatus includes a first switch coupled between a terminal for receiving an input voltage and a top plate node, and having a first control terminal; a second switch coupled between the top plate node and a switching node, and having a second control terminal; a third switch coupled between the switching node and a bottom plate node and having a third control terminal; a fourth switch coupled between the bottom plate node and a ground terminal, and having a fourth control terminal; a flying capacitor coupled between the top plate node and the bottom plate node; a fifth switch coupled between the top plate node and an auxiliary node; a sixth switch coupled between the auxiliary node and the bottom plate node; and an auxiliary capacitor coupled between the auxiliary control terminal and a ground terminal.

Modular Multilevel Converter

A modular multilevel converter includes a plurality of sub-modules. Each of the sub modules has at least two electronic switching elements, an electrical energy storage device, two galvanic power terminals, an optical communication input () and an optical communication output. A plurality of the sub-modules is connected to a series circuit by way of their communication input and communication output. 117- (canceled)18. A modular multilevel converter , comprising:sub modules each having at least two electronic switching elements, an electrical energy storage device, two electrical connections, an optical communication input and an optical communication output;wherein a plurality of said sub modules are connected by way of said communication input and said communication output thereof to form a series circuit.19. The modular multilevel converter according to claim 18 , wherein a first said sub module of said series circuit and a last said sub module of said series circuit are each connected to a communication device that is allocated to said series circuit.20. The modular multilevel converter according to claim 19 , wherein said sub modules of said series circuit and said communication device allocated to said series circuit are connected to form a ring structure.21. The modular multilevel converter according to claim 19 , wherein said communication device is a master and each of said sub modules of said series circuit is a slave.22. The modular multilevel converter according to claim 18 , wherein at least one of said sub modules includes an optical bypass device.23. The modular multilevel converter according to claim 22 , wherein said bypass device is configured to at least intermittently optically connect said optical communication input of said sub module to said optical communication output of said sub module.24. The modular multilevel converter according to claim 22 , wherein said bypass device includes an optical mirror.25. The modular multilevel converter ...

Method for controlling extraction of power from multiple photo voltaic (pv) arrays and system thereof

Embodiments herein provide a system and method for controlling extraction of power from multiple Photo Voltaic (PV) arrays. At least two converters and at least two Photo Voltaic (PV) arrays are configured. The power extraction is controlled through one of an injection of Direct Current (Idc) into output current of each of the at least two converters, or by performing a phase shifting of each of the output current of each of the at least two converters.

Multi-level inverter

Embodiments of the present disclosure disclose a multi-level inverter, which belongs to the field of power electronics. The multi-level inverter includes a main topology, at least four resistors, a switch, and a controller. The main topology includes a power supply, a flying capacitor, and at least four semiconductor switches. The flying capacitor is electrically connected to the power supply. The controller is configured to: before the main topology works, control the switch to be closed, and when detecting that charging the flying capacitor is completed, control the switch to be open. The multi-level inverter provided in the present disclosure can prevent a semiconductor switch from being damaged.

Dc/ac converter, power generation plant and operating method for a dc/ac converter

A DC/AC converter for converting DC power of a number of inductively connected generators into power grid conformal AC power for feeding into a connected power grid with a number of phases, includes an intermediate circuit with a positive and a negative intermediate circuit connection, and for each phase, a bridge. Each bridge includes a first switch between the positive intermediate circuit connection and a phase terminal, a second switch connected between a positive generator terminal of the generator and the phase terminal, a third switch connected between a negative generator terminal of the generator and the phase terminal, and a fourth switch between the negative intermediate circuit connection and the phase terminal.

Switch network of a multilevel power converter architecture

A power converter provides a pyramidal structure of switches communicating between a capacitive divider at the base of the pyramid and a terminal at the top of the pyramid to provide a transformation of a relationship between current and voltage in power transferred between the capacitive divider and the terminal at the top of the pyramid while providing reduced electrical interference and electrical rate of change (dv/dt).

POWER CONVERTER SUB-MODULE

There is disclosed a sub-module, for a power converter module, the sub-module comprising: a busbar having a busbar terminal; a converter component having a component terminal; and a flexible connector coupled to the busbar terminal and the component terminal to form an electrical connection therebetween, the connector extending along a first axis X between the busbar terminal and the component terminal. The connector is flexible so that there is at least one degree of freedom between the busbar terminal and the component terminal. 1. A sub-module for a power converter module , the sub-module comprising:a busbar having a busbar terminal;a converter component having a component terminal; anda flexible connector coupled to the busbar terminal and the component terminal to form an electrical connection therebetween, the connector extending along a first axis between the busbar terminal and the component terminal;wherein the connector is flexible so that there is at least one degree of freedom between the busbar terminal and the component terminal.2. The sub-module according to claim 1 , wherein the converter component is a switching element or an energy storage element.3. The sub-module according to claim 1 , wherein the connector is extendible and compressible along the first axis so that there is at least an axial degree of freedom along the first axis between the busbar terminal and the component.4. The sub-module according to claim 3 , wherein the connector has a stiffness along the first axis of 105 N/m or less.5. The sub-module according to claim 1 , wherein the connector is configured to bend about at least a second axis so that there are at least three degrees of freedom between the busbar terminal and the component terminal.6. The sub-module according to claim 1 , wherein the connector is configured to bend about two axes so that there are at least five degrees of freedom between the busbar terminal and the component terminal.7. The sub-module according to ...

REDUNDANT ENERGY ACQUISITION CIRCUIT OF POWER MODULE, AND CONTROL METHOD THEREOF

A redundant energy acquisition circuit of a power module includes at least one power semiconductor device, a first capacitor, and a first bypass switch. The redundant energy acquisition circuit of the power module includes: a power supply board acquiring energy from the first capacitor, supplying power to a control board, and charging a discharge circuit. A first charging circuit has one end connected to a positive electrode of the first capacitor and another end connected to the discharge circuit, and charges the discharge circuit when the power supply board is not operating normally. The control board controls the discharge circuit to close. The discharge circuit discharges and triggers the first bypass switch to close after the discharge circuit is closed. 1. A redundant energy acquisition circuit of a power module , the power module comprising at least one power semiconductor device , a first capacitor and a first bypass switch , and the redundant energy acquisition circuit of the power module comprising:a power supply board acquiring energy from the first capacitor, supplying power to a control board, and charging a discharge circuit;a first charging circuit having one end connected to a positive electrode of the first capacitor and another end connected to the discharge circuit, and charging the discharge circuit when the power supply board is not operating normally;the control board controlling the discharge circuit to close; andthe discharge circuit discharging and triggering the first bypass switch to close after being closed.2. The redundant energy acquisition circuit of the power module according to claim 1 , wherein the redundant energy acquisition circuit of the power module further comprises:a second charging circuit connected in parallel with the first capacitor and triggering the discharge circuit to close when the control board is not operating normally.3. The redundant energy acquisition circuit of the power module according to claim 2 , wherein ...

Power conversion device

A power conversion device 300 includes: an AC/DC converter section 10 which has an initial charging circuit 36 that initially charges a smoothing capacitor 22 provided at an output portion, and converts alternating current power into direct current power; a DC/DC converter section 11 which performs voltage conversion of direct current power supplied from the smoothing capacitor 22 ; and a control unit 5 which controls output of the AC/DC converter section 10 and output supplied from the DC/DC converter section 11 . The control unit 5 performs a predetermined charging from the initial charging circuit 36 to the smoothing capacitor 22 at start-up of the AC/DC converter section 10 , and starts the operation of the DC/DC converter section 11 after completion of charging, whereby the circuit can be protected from an inrush current at start-up.

Pre-charge techniques for a multi-level flying capacitor converter

A circuit includes first and second transistors, a capacitor, and a controller. The controller is coupled to the control inputs of the first and second transistors. The controller configured to, during a first mode and in accordance with a first time-varying duty cycle, turn on and off the first transistor while turning on the second transistor when the first transistor is off. The controller is also configured to, during a second mode following the first mode, and in accordance with a second time-varying duty cycle, turn on and off the first transistor while turning on the second transistor when the first transistor is off.

Method for operating a multi-phase modular multi-level power converter

A method for operating a multi-phase modular power inverter having DC input terminals and AC phase voltage output terminals connected to a load, phase modules connected between the DC input terminals, with each phase module composed of valve arms connected in series at a connection point forming an AC phase voltage output terminal which is connected to a load, each valve arm having a plurality of power inverter cells with turn-off semiconductor switches and a choke connected in series, includes controlling, with a control device, the turn-off semiconductor switches of each power inverter cell as a function of a plurality of setpoint values, wherein the setpoint values are generated such that a time-averaged energy value stored in a capacitor of a corresponding power inverter cells is predetermined by an operating point of the load and-or an operating mode of the modular multi-level power inverter.

Power conversion device

A power conversion device includes a plurality of leg circuits and a control device. The plurality of leg circuits correspond to respective phases of an AC circuit and connected in parallel between common first and second DC terminals. Each leg circuit includes a plurality of chopper cells each including an energy storage and cascaded to one another and at least one inductance connected in series to the plurality of chopper cells. The control device controls an operation of only at least one chopper cell included in each leg circuit based on a circulating current which circulates through the leg circuits.

Converter Module For A Multi-Stage Converter And Method For Operating Said Converter Module

A converter module for a multi-stage converter includes an energy storage device connected in parallel with a series circuit of a first and a second semiconductor switching unit. At least one of the semiconductor switching units has a bidirectional switch. A switch-on unit is connected in parallel with the bidirectional switch. With the switch-on unit there can be produced a switch-on voltage for switching on the bidirectional switch from a voltage dropping across the bidirectional switch. There is also disclosed a multi-stage converter having the novel converter module and a method for operating the converter module. 112-. (canceled)13. A converter module for a multi-stage converter , comprising:a series circuit of a first semiconductor switching unit and a second semiconductor switching unit;at least one of said first and second semiconductor switching units having a bidirectional switch;an energy storage device connected in parallel with said series circuit; anda switch-on unit connected in parallel with said bidirectional switch and configured to generate a switch-on voltage for switching on said bidirectional switch from a voltage dropping across said bidirectional switch.14. The converter module according to claim 13 , wherein said switch-on unit is configured to generate the switch-on voltage by way of a voltage division of the voltage dropping across the bidirectional switch.15. The converter module according to claim 13 , wherein said switch-on unit comprises a deactivation switch enabling said switch-on unit to be deactivated.16. The converter module according to claim 15 , wherein said bidirectional switch comprises a first terminal claim 15 , a second terminal and a control terminal claim 15 , and said switch-on unit comprises:a first divider branch between said first terminal of said bidirectional switch and a central potential node;a second divider branch between said second terminal of said bidirectional switch and the central potential node; anda ...

POWER CONVERSION DEVICE

Each of a plurality of specified chopper cells which are some of a plurality of chopper cells included in each leg circuit in a power conversion device is configured as a full bridge. A control device controls operations of first and second switching elements of each specified chopper cell based on a circulating current which circulates through each leg circuit. The control device controls operations of third and fourth switching elements of each specified chopper cell based on a voltage of a capacitor of the specified chopper cell. 1. A power conversion device which converts power between a DC circuit and an AC circuit , the power conversion device comprising: [ a plurality of converter cells cascaded to one another and each including an energy storage; and', 'at least one inductor connected in series to the plurality of converter cells,, 'each leg circuit including, a capacitor as the energy storage;', 'first and second switching elements connected in parallel to the capacitor and connected in series to each other; and', 'third and fourth switching elements connected in parallel to the capacitor and connected in series to each other,, 'each of a plurality of specified converter cells which are some of the plurality of converter cells included in each leg circuit including, 'the capacitor being capable of being charged and discharging through a connection node of the first and second switching elements and a connection node of the third and fourth switching elements; and, 'a plurality of leg circuits which correspond to respective phases of the AC circuit and are connected in parallel between common first and second DC terminals,'}a control device which controls operations of the plurality of converter cells included in each leg circuit,the control device controlling operations of the first and second switching elements of each specified converter cell based on a circulating current which circulates through each leg circuit,the control device controlling operations ...

THREE-LEVEL INVERTER SWITCHING

Inverter circuit operation for managing power factor changes is provided. Various modes of switch timing may be employed near zero-voltage crossings. Inverter switch timing may change during a cycle such that one timing strategy is employed approaching or leaving a zero-voltage crossing while another timing strategy is employed at other times of the cycle. 1. An electrical conversion process comprising:operating a first electrical circuit, the first circuit configured to receive dc voltage and convert the received dc voltage into cyclically alternating voltage and cyclically alternating current;cyclically outputting the alternating voltage and the alternating current to a first node and a second node; and{'sub': 'S', 'claim-text': {'sub': 'S', 'wherein the time Tis set in relation to a switching frequency of switches creating the cyclical output of alternating voltage at the first node or the second node.'}, 'when a non-unity power factor exists for the alternating output voltage and the alternating output current, shorting the first node across the second node for a time Twhen the alternating output voltage phase angle is within ±22.5° of a zero-voltage crossing,'}2. The process of wherein the alternating output voltage phase angle is within 20 degrees of a zero-voltage crossing.3. The process of wherein the electrical circuit comprises four switches in an H-Bridge topology and these four switches are switching in pairs with a first pair switching at a power line frequency and a second pair switching at a frequency at least one hundred times the power line frequency and wherein during zero-voltage crossing the first pair switching frequency increases to a frequency greater than power line frequency.4. The process of wherein the duration of the time Ts is set as a percentage of switching frequency.5. The process of wherein the first electrical circuit comprises switches in an inverter topology and wherein the time Ts exceeds half of a period of time to fully cycle a ...

MULTILEVEL CONVERTER

A modular multilevel converter has a plurality of sub-modules, each of which includes at least two electronic switching elements and an electrical energy storage device. The sub-modules are controlled by a control device. An optical output of the control device of the converter is connected to an input of an optical distributor by way of a first optical waveguide. A plurality of outputs of the optical distributor are individually connected to an optical input of one of the sub-modules, respectively, by way of a second optical waveguide. 118-. (canceled)19. A modular multilevel converter , comprising:a multiplicity of sub modules each having at least two electronic switching elements and an electrical energy storage device, each of said sub modules having an optical input;a control device for controlling said sub modules, said control device having at least one optical output; andan optical distributor having at least one input connected to said optical output of said control device by way of a first optical fiber, and said optical distributor having a multiplicity of outputs connected to said optical input of a respective one of said sub modules by way of a respective second optical fiber.20. The modular multilevel converter according to claim 19 , wherein each of said outputs of said optical distributor is connected to a different one of said sub modules.21. The modular multilevel converter according to claim 19 , wherein:said control device has a multiplicity of optical inputs, and an optical output of each of said sub modules is connected to one of said optical inputs of said control device by way of a third optical fiber; oran optical collector has a multiplicity of optical inputs, and an optical output of each of said sub modules is connected to one of said optical inputs of said optical collector by way of a third optical fiber, and an optical output of said optical collector is connected to an optical input of said control device by way of a fourth optical ...

DC CHOPPER FOR MMC CELL WITH INTEGRATED CHOPPER RESISTOR

This disclosure proposes a topology that integrates a DC chopper into the Modular Multilevel Converter (MMC) cells of a power converter. The integrated DC chopper may include chopper resistors that may also be advantageously integrated into a heat sink for a power module comprising at least the power transistors of the MMC cell. Embodiments herein also describe a method for using an MMC cell's IGBTs and chopper resistors for providing a safe discharge of both cell capacitors and DC-link capacitors in different operating conditions. 1. A modular multilevel converter (MMC) , comprising: at least two main transistors connected in series between a first voltage rail and a second voltage rail; and', 'a direct current (DC) chopper connected between the first voltage rail and the second voltage rail., 'a plurality of MMC cells, each MMC cell comprising2. The MMC according to claim 1 , wherein for each MMC cell claim 1 , the at least two main transistors are each connected to an anti-parallel diode and wherein the DC chopper comprises a dump resistor integrated into a heat sink for each of the MMC cells.3. The MMC according to claim 2 , wherein the DC chopper comprises a controllable chopper transistor connected in series with the dump resistor.4. The MMC according to claim 3 , wherein the dump resistor is connected to the first voltage rail at a first end and the controllable chopper transistor at a second end.5. The MMC according to claim 2 , wherein the DC chopper further comprises a diode connected in parallel with the dump resistor.6. The MMC according to claim 5 , wherein the diode is integrated into a Diode-integrated Insulated Gate Bipolar Transistor.7. The MMC according to claim 1 , wherein the at least two main transistors are connected in parallel with the DC chopper.8. The MMC according to claim 1 , further comprising:a capacitor connected between the first voltage rail and the second voltage rail and in parallel with the DC chopper.9. The MMC according to claim ...

MULTIPHASE MULTILEVEL POWER CONVERTER

A multi-phase multi-stage power converter includes a phase module having a power converter module formed of two-pole submodules connected in series and having a plurality of semiconductor switches connected in series, an energy store charged and discharged by the semiconductor switches, a bypass switch short-circuiting the energy store upon exceeding a first limit voltage, and a signal input for a blocking signal opening all semiconductor switches. The submodules are protected from overloading in a simpler manner by connecting a module arrester in parallel with the power converter module. The module arrester limits the power converter voltage like a valve upon exceeding a second limit voltage. The module arrester operates in blocking mode below the second limit voltage and in conducting mode above the second limit voltage. A current limiting the power converter voltage flows through the module arrester in conducting mode. 16-. (canceled)7. A multiphase multilevel power converter , comprising: a) a plurality of semiconductor switches connected together in series,', 'b) an energy storage device to be charged and discharged by said semiconductor switches,', 'c) a bypass switch short-circuiting said energy storage device upon exceeding an associated first limit voltage,', 'd) a signal input for a blocking signal opening all of said semiconductor switches of said submodule; and, 'a phase module including a power converter module formed of a multiplicity of two-pole submodules being electrically connected in series, said two-pole submodules each includinga module arrester connected in parallel with said power converter module and acting as a valve limiting a power converter voltage upon exceeding a second limit voltage, said module arrester operating in a blocking mode below said second limit voltage and operating in a conducting mode above said second limit voltage, and a current limiting said power converter voltage flowing through said module arrester in said ...

Power-converting device and power conditioner using the same

A first bidirectional switch is electrically connected between a first connection point which is a connection point of a first switching element and a second switching element and a second connection point which is a connection point of a seventh switching element and an eighth switching element. A second bidirectional switch is electrically connected between a third connection point which is a connection point of a third switching element and a fourth switching element and a fourth connection point which is a connection point of a fifth switching element and a sixth switching element. A power-converting device is configured to generate an output voltage between a first output point and a second output point.

Uninterruptible Power Supply Circuit

An uninterruptible power supply circuit is provided. The uninterruptible power supply circuit includes a bidirectional selector switch, a first-type bidirectional converter, a second-type bidirectional converter, an energy storage apparatus, and a filtering apparatus, and is alternatively connected to an alternating-current power supply and the energy storage apparatus by using the bidirectional selector switch; the first-type bidirectional converter is disposed between the bidirectional selector switch and the filtering apparatus, the second-type bidirectional converter is disposed between the filtering apparatus and a load, and both the first-type bidirectional converter and the second-type bidirectional converter have a function of rectifying or inverting. By using a bidirectional converter and a bidirectional selector switch, alternating-current commercial power, the energy storage apparatus, and a charger required by the energy storage apparatus can share the bidirectional converter; compared with an existing uninterruptible power supply circuit, no extra charger or high-power conversion circuit is required.

High Frequency Multi-Level Inverter

A multi-level inverter having at least two banks, each bank containing a plurality of low voltage MOSFET transistors. A processor configured to switch the plurality of low voltage MOSFET transistors in each bank to switch at multiple times during each cycle.

METHOD FOR CONTROLLING OUTPUT VOLTAGE AT A MULTILEVEL INVERTER

A 15-level multilevel inverter circuit includes an outer circuit, an inner circuit, a polarity changing circuit and a computing device. The outer circuit and the inner circuit include a plurality of DC voltage supplies. Each DC voltage supply has a positive and a negative terminal. The outer circuit, the inner circuit and the polarity changing circuit include a plurality of unidirectional power switches. Each unidirectional power switch is a transistor with a diode connected in parallel to the transistor. The computing device is configured to provide control signals to the gates of the plurality of the unidirectional power switches of the outer circuit and the inner circuit to add or subtract the voltage of each of inner DC voltage supplies to form square waveforms approximating sinusoidal waveforms, and to the gates of the plurality of the unidirectional power switches of the polarity changing circuit to switch the polarity of the voltage.

MICROPROCESSOR-CONTROLLED POWER SYSTEM FOR A BATTERY-POWERED MULTILEVEL INVERTER CIRCUIT

A 15-level multilevel inverter circuit includes an outer circuit, an inner circuit, a polarity changing circuit and a computing device. The outer circuit and the inner circuit include a plurality of DC voltage supplies. Each DC voltage supply has a positive and a negative terminal. The outer circuit, the inner circuit and the polarity changing circuit include a plurality of unidirectional power switches. Each unidirectional power switch is a transistor with a diode connected in parallel to the transistor. The computing device is configured to provide control signals to the gates of the plurality of the unidirectional power switches of the outer circuit and the inner circuit to add or subtract the voltage of each of inner DC voltage supplies to form square waveforms approximating sinusoidal waveforms, and to the gates of the plurality of the unidirectional power switches of the polarity changing circuit to switch the polarity of the voltage.

METHOD OF OPERATING A MULTI-LEVEL SWITCHED CAPACITOR BOOST INVERTER

A multi-level switched capacitor boost inverter includes a series connection of a two-switched capacitor circuit, a source module and at least one one-switched capacitor circuit. Level-shifted pulse width modulation is used to apply gate pulses to the switches. The multi-level switched capacitor boost inverter uses only three capacitors and a single DC voltage source to generate thirteen voltage levels at load terminals with a voltage gain of three. The capacitors of the two-switched capacitor circuit are self-balancing. Additional one-switched capacitor circuits can be added in series with the inverter. Each additional one-switched capacitor circuit increases the number of levels and increases the gain by one.

Multilevel converter

A power converter includes at least one leg having a first string operatively coupled to a second string via a first connecting node and a second connecting node. The first string includes a first branch and a second branch operatively coupled via a third connecting node. Each of the branches has a plurality of switching units, a controllable semiconductor switch and the first connecting node and the second connecting node. The first string is operatively coupled across a first bus and a second bus. Furthermore, the second string includes a plurality of controllable semiconductor switches.

Method And Apparatus For Controlling Hybrid Direct-Current Transmission System

A method and apparatus for controlling a hybrid direct-current (DC) transmission system. The method comprises: adjusting the total number of inserted sub-modules of a modular multi-level converter and the polarity of an output level of the inserted sub-modules in real time, according to a DC voltage of a rectifier station at other end; or adjusting the total number of inserted sub-modules of a modular multi-level converter and the polarity of an output level of the inserted sub-modules in real time, according to the magnitude of a DC current or DC power; or adjusting the total number of inserted sub-modules of a modular multi-level converter and the polarity of an output level of the inserted sub-modules in real time, according to both the magnitude of the DC current and the DC voltage of the rectifier station at the other end. The method can effectively control the DC voltage and the direct current of a hybrid DC transmission system, avoiding the power transmitting breakdown. 1. A method for controlling a hybrid direct-current (DC) transmission system , characterized in that , comprising: adjusting , by the hybrid direct-current transmission system according to a DC voltage of a rectifier station at other end , a total number of inserted sub-modules of a modular multi-level converter and a polarity of an output level of the inserted sub-modules in real time; oradjusting, by the hybrid direct-current transmission system according to a magnitude of a DC current or DC power, the total number of the inserted sub-modules of the modular multi-level converter and the polarity of the output level of the inserted sub-modules in real time; oradjusting, by the hybrid direct-current transmission system according to both the magnitude of the DC current and the DC voltage of the rectifier station at the other end, the total number of the inserted sub-modules of the modular multi-level converter and the polarity of the output level of the inserted sub-modules in real time.2. The ...

DUAL SUBMODULE FOR A MODULAR MULTILEVEL CONVERTER AND MODULAR MULTILEVEL CONVERTER INCLUDING THE SAME

A dual submodule is created for a modular multilevel converter, whereby the dual submodule has two interconnected submodules, whereby each submodule has an asymmetrical half-bridge circuit with two parallel bridge branches, which are connected between a first and a second terminal connection of the submodule, whereby each bridge branch is formed from a series circuit of a power semiconductor switch, and a diode, whereby the power semiconductor switch is allocated to an antiparallel free-wheeling diode, and has a capacitor, which is connected in parallel with the asymmetrical half-bridge circuit between the first and the second terminal connections of the module. The submodules are connected to each other via their AC terminals to form the dual submodule. Further, a modular multilevel converter is created, comprising a number of such dual submodules in each of its converter branches. 1. A dual submodule for a modular multilevel converter , whereby comprising:two interconnected submodules, each submodule comprising:an asymmetrical half-bridge circuit with two parallel bridge branches connected between a first and a second terminal connection of the submodule, whereby each bridge branch is formed from a series circuit of a power semiconductor switch and a diode, whereby an antiparallel free-wheeling diode is allocated to the power semiconductor switch; anda capacitor is connected in parallel to the asymmetrical half-bridge circuit between the first and the second terminal connections of the submodule;whereby wherein a connection point between a power semiconductor switch and a diode of each bridge branch of one of the submodules is connected directly to a respective connection point between a power semiconductor switch and a diode of a bridge branch of the other submodule to form the dual submodule.2. The dual submodule as described in claim 1 , wherein a first claim 1 , more negative terminal connection of one of the submodules forms a first input/output terminal of ...

Multiphase Power Converter

A multiphase power converter and a corresponding method is presented. The multiphase power converter contains a first and a second constituent switched-mode power converter. The first constituent switched-mode power converter provides, both in a first mode of operation and in a second mode of operation, a first phase current to an output of the converter. The second constituent switched-mode power converter provides, in the second mode, a second phase current to the output of the converter. The converter switches, depending on an operation condition of the converter, between the first mode and the second mode. A first transconductance of the first constituent switched-mode power converter is adapted when switching between the first mode and the second mode. By adapting the first transconductance, unsteadiness of the output voltage of the converter occurring during the switching between both modes of operation is minimized. 1) A multiphase power converter comprising a first and a second constituent switched-mode power converter , whereinthe first constituent switched-mode power converter is configured to provide, both in a first mode of operation and in a second mode of operation, a first phase current to an output of the multiphase power converter,the second constituent switched-mode power converter is configured to provide, in the second mode of operation, a second phase current to the output of the multiphase power converter, andthe multiphase power converter is configured to switch, depending on an operation condition of the multiphase power converter, between the first mode of operation and the second mode of operation, and configured to adapt a first transconductance of the first constituent switched-mode power converter when switching between the first mode of operation and the second mode of operation.2) The multiphase power converter according to claim 1 , wherein the multiphase power converter is configured to increase the first transconductance when ...

POWER CONVERSION DEVICE

A control unit activates a power supply circuit when an input voltage becomes equal to or greater than a first threshold value. The control unit brings a switch into a conductive state when the input voltage becomes equal to or greater than a second threshold value and brings the switch into a non-conductive state when the input voltage becomes equal to or less than a third threshold value. The control unit deactivates the power supply circuit when the input voltage becomes equal to or less than a fourth threshold value. Based on the number of times that the input voltage becomes equal to or greater than the second threshold value after the power supply circuit is activated, the control unit further enables a latch function for holding the power supply circuit in a deactivated state. 1. A power conversion device comprising:a power converter including an arm that is configured with a series connection of at least one or more unit converters; anda controller configured to control the power converter, a main circuit that includes a plurality of switching elements and a capacitor, the main circuit being configured to control the plurality of switching elements to convert a voltage across the capacitor into an AC voltage,', 'a control circuit configured to control the plurality of switching elements according to a control signal received from the controller, and', 'a power supply configured to step down the voltage across the capacitor to generate a power supply voltage, and supply the power supply voltage to the control circuit,, 'the at least one or more unit converters each including'} a first input terminal and a second input terminal,', 'a voltage sensor configured to detect an input voltage supplied between the first input terminal and the second input terminal from the capacitor,', 'a switch and a resistance that are electrically connected in series between the first input terminal and the second input terminal,', 'a power supply circuit electrically connected ...

POWER CONVERSION DEVICE

In one embodiment, a power conversion device that converts power between a DC circuit and an AC circuit includes a plurality of leg circuits connected in parallel between first and second DC terminals and electrically connected to the AC circuit. Each of the plurality of leg circuits includes at least one first converter cell and a plurality of second converter cells other than the first converter cell. A first control signal that controls switching of a semiconductor switching element included in at least one first converter cell is higher in frequency than a second control signal that controls switching of a semiconductor switching element included in each of the plurality of second converter cells. 1. A power conversion device that converts power between a DC circuit and an AC circuit , the power conversion device comprising: at least one first converter cell; and', 'a plurality of second converter cells other than the at least one first converter cell,, 'a plurality of leg circuits connected in parallel between a first DC terminal and a second DC terminal and electrically connected to the AC circuit, each of the plurality of leg circuits includingeach of the at least one first converter cell and the plurality of second converter cells including a capacitor and a plurality of semiconductor switching elements,a first control signal that controls switching of each of the semiconductor switching elements included in the at least one first converter cell being higher in frequency than a second control signal that controls switching of each of the semiconductor switching elements included in each of the plurality of second converter cells.2. The power conversion device according to claim 1 , whereinthe first control signal and the second control signal are generated based on voltage command values different from each other.3. The power conversion device according to claim 2 , whereinthe first control signal is generated based on a circulating current that circulates ...

High Power Grid System with Thyristor Controls

A line commutated converter (LCC) for a high voltage direct current power converter, the LCC comprising at least one LCC bridge circuit for connection to at least one terminal of a DC system, each bridge circuit comprising a plurality of arms, each associated with a respective phase of an AC system, each arm comprising: an upper thyristor valve or valves, and lower thyristor valve or valves connected in series; an associated branch extending from between the upper and lower thyristors; and at least one thyristor-based capacitor module for each phase, each module comprising a plurality of module thyristors, the or each capacitor module operable to insert a main capacitor into the respective arm of the bridge circuit by firing at least one or more of said module thyristors. 1. A line commutated converter , LCC , for a high-voltage , direct current , HVDC , power converter , the LCC comprising at least one LCC bridge circuit for connection to at least one terminal of a DC system , each bridge circuit comprising a plurality of arms , each associated with a respective phase of an AC system , each arm comprising:an upper thyristor valve or valves, and lower thyristor valve or valves connected in series;an associated branch extending from between the upper and lower thyristors; andat least one thyristor-based capacitor module for each phase, each module comprising a plurality of module thyristors, the or each capacitor module operable to insert a main capacitor into the respective arm of the bridge circuit by firing at least one or more of said module thyristors:wherein each thyristor-based capacitor module further comprises a plurality of subsidiary capacitors and a plurality of inductors; andwherein the subsidiary capacitors and inductors are operable to form a plurality of at least two L-C oscillation circuits within the thyristor-based capacitor module.2. The LCC of wherein the current rating of the at least one thyristor-based capacitor module is as high as that of ...

Power conversion circuit and power conversion system

A power converter, includes a first terminal and a second terminal which are connected to a direct current; a third terminal connected to an alternating current; N multi-level bridge arms connected in parallel to the first terminal and the second terminal, where the N multi-level bridge arms work in a parallel-interleaved manner, each multi-level bridge arm of the N multi-level bridge arms includes an alternating current node, and multiple time-varying levels are generated at the alternating current node, where the multiple levels are more than two levels; and a coupling inductor, including N windings coupled by one common magnetic core, where one end of each winding of the N windings is connected to an alternating current node of one multi-level bridge arm of the N multi-level bridge arms, and the other end of each winding of the N windings is connected to the third terminal.

METHOD FOR CONTROLLING A POWER CONVERTER, AND POWER CONVERTER SYSTEM HAVING SUCH A POWER CONVERTER

A method controls a power converter in which a target value of a control parameter is limited by at least one limiting value. The method is characterized in that the at least one limiting value is determined dynamically over time as a function of a power converter temperature. A power converter system having a control device is provided and configured to carry out the method. 110-. (canceled)11. A method for controlling a power converter , in which a setpoint of a control parameter is limited by at least one limiting value , which comprises the step of:determining the at least one limiting value in a temporally dynamic manner, in dependence on a power converter temperature.12. The method according to claim 11 , wherein the power converter temperature is a semiconductor temperature of a semiconductor switch of the power converter.13. The method according to claim 12 , wherein the power converter temperature is determined based on a temperature model of the semiconductor switch.14. The method according to claim 13 , wherein the temperature model contains a power loss model of the semiconductor switch.15. The method according to claim 13 , wherein the power converter is a modular multistage converter claim 13 , and the power converter temperature is obtained from at least one of following measurement parameters:a branch current of a power converter branch of the power converter;an energy storage device voltage of an energy storage device of a switching module of the power converter; anda switching state of the switching module.16. The method according to claim 11 , wherein the power converter temperature is obtained using a temperature measurement at the power converter.17. The method according to claim 16 , which further comprises measuring a cooling water temperature of cooling water for cooling the power converter.18. The method according to claim 11 , which further comprises determining the at least one limiting value in dependence on setpoints of further control ...

MODULAR MULTILEVEL CONVERTER AND POWER ELECTRONIC TRANSFORMER

A modular multilevel converter and a power electronic transformer is provided. The modular multilevel converter includes: a low-frequency AC to DC conversion module, comprising three branch circuits connected in parallel between output ends, each branch circuit being formed of multiple IGBT half-bridge circuits connected in series, and an electric coupling point of two adjacent IGBT half-bridge circuits in a middle position of the branch circuit being connected to a voltage input end Vin; a DC to high-frequency AC conversion module, connected between the output ends, the DC to high-frequency AC conversion module being formed of multiple IGBT half-bridge circuits connected in series, the DC to high-frequency AC conversion module having multiple sets of output ends. The MMC and power electronic transformer includes a smaller volume, lower cost and better stability in use. 1. A modular multilevel converter (MMC) , comprising: 'a DC to high-frequency AC conversion module, connected between the output ends, the DC to high-frequency AC conversion module being formed of multiple IGBT half-bridge circuits connected in series, the DC to high-frequency AC conversion module including multiple sets of output ends, each set of output ends including a first output end and a second output end, the first output end being connected to an electric coupling point between two adjacent IGBT half-bridge circuits of the multiple IGBT half-bridge circuits, and the second output end being connected to an electric coupling point between another two adjacent IGBT half-bridge circuits of the multiple IGBT half-bridge circuits.', 'a low-frequency AC to DC conversion module including at least three branch circuits connected in parallel between output ends, each branch circuit of the at least three branch circuits being formed of multiple IGBT half-bridge circuits connected in series, and an electric coupling point of two adjacent IGBT half-bridge circuits of the multiple IGBT half-bridge ...

Converter and power conversion device using same

A converter includes a first diode having an anode and a cathode connected respectively to an input terminal and a first output terminal, a second diode having an anode and a cathode connected respectively to a second output terminal and the input terminal, a first transistor connected between the first output terminal and the input terminal, a second transistor connected between the input terminal and the second output terminal, and a bidirectional switch connected between the input terminal and a third output terminal and including third to sixth diodes and a third transistor. Each of the first diode, the second diode, and the third transistor is made of a wide bandgap semiconductor. Each of the first and second transistors and the third to sixth diodes is made of a semiconductor other than the wide bandgap semiconductor.

Transformerless multilevel converter

An exemplary medium voltage system includes a multilevel converter connected to a grid connection. The multilevel converter is configured for converting a first multiphase current provided at the grid connection into a second current. The system includes a common mode filter, which, for each phase of the first current, includes a phase filter connected to the respective phase. Each phase filter is connected to a common filter star point which is connected to ground, includes an inductance and a capacitance connected in series, and includes a resistance connected in series with the capacitance such that the inductance and the resistor are connected in parallel. The common mode filter includes an impedance between the common filter star point and the ground.