Adjustable stepping passive attenuation circuit for test of power line carrier

The invention relates to an adjustable stepping passive attenuation circuit for test of a lower line carrier. A low pass filter part and a high frequency signal attenuation part are connected parallelly so as to form the adjustable stepping passive attenuation circuit. The low pass filter part adopts a multistage longitudinal redundancy check (LRC) low pass filter circuit, thereby shielding external interference. The high frequency signal attenuation part comprises a multistage pi type/T type/ bridge T type balance attenuation network. All the three network types belong to a symmetrical attenuation network and are mainly used for signal attenuation. While a 220V power supply interference signal is shielded, stepping attenuation regulation and control on the high frequency power line carrier signal is realized. The same attenuation degree of general carrier frequency bands is realized and the attenuation degree is highly consistent.

Inside vibrating device of tunnel junction inspection pipeline liquid

The utility model relates to an inside vibrating device of tunnel junction inspection pipeline liquid, including basement, metal electrode, two metal electrode seal inside the basement, and two metal electrode tops are relative, and the distance between the top is 0.01nm -100nm, and two metal electrode tail ends are equipped with outer guide line, and the basement is glued and is sticked on the inside pipe wall of pipeline. The utility model discloses a device is when having liquid flow management way, and liquid is inside must to have the existence of impact, vibration because of each cross -section velocity of flow differs, and these signals cause that the distance between the inside metal electrode of tunnel junction foil gage changes can pass to the tunnel junction foil gage through the pipeline on, and the tunnel current that produces so also changes thereupon, vibrates water impact through the collection tunnel current and expresses.

Forward sequence direction quadrangle impedance relay applied for serial supplementary line

This invention relates to a positive-sequence direction quadrangle impedance relay formed by combining positive-sequence dirdction elements and offset character quadrangle impedance elements used in serial-compensating circuit characterizing that the resistance offset of the offset character quadrangle impedance element is R'=min(0.5RZD, 0.5ZZD), when serial-compensation capacitance appears in the positive exit, the reactance offset is X'=XC, if not, it is X'=min(0.5 Omega, 0.5ZZD), and the polarized voltage of the positive direction element is U'1=U1x®ªU1/Un®ª+ZFXx I, when reverse current may appear to the circuit, compensation is carried out and its impedance is: XC-ZS Подробнее

Circuit protection order component phase selection method using both end information

Series capacitor compensation circuit distance protection method by combining phase-comparison relay

The invention discloses a novel series capacitor compensation circuit distance protection method by combining a phase-comparison relay. The method is characterized by comprising the following steps: 1) calculation of compensation voltage: using the series capacitor installation position (before capacitors) as a compensation point, and utilizing the current and voltage values on the protection installation position to calculate compensation voltage *S; 2) action judgment of the phase-comparison relay, carrying out phase comparison on the calculated compensation voltage *S and the correspondingpositive sequence voltage on the protection installation position; 3) protection logic, if the phase-comparison relay acts, the distance protection is directly carried out without overriding measures;if not, the level detection logic is carried out on failure of the phase-comparison relay. The invention can enhance the sensitivity of distance protection on the basis of reliable overriding prevention ...

Differential protection method for preventing false operation during current disappearance

The invention relates to a differential protection method for preventing false operation during current disappearandce, which comprises the following steps: preparing to trip according to the differential protection action after a protection device starts for 60ms; then, using a waveform similarity criterion to compute waveform similarity coefficients computed in a short window data of a differential action element 20ms before; if the waveform similarity coefficient values in the data window are all less than 0.2, tripping immediately; and if the condition that the waveform similarity coefficient values in the data window are greater than 0.2 exists, delaying differential protection for 20ms, and triggering port if the fault does not disappear. The method is based on a least square filtering principle, compares whether a target alternating quantity is the normal system waveform or distorted waveform according to the waveform similarity coefficients, and does not differentiate the fault ...

A current differential protection judgement method applicable to multi-end power input line

The invention relates to a criterion method for current differential protection applicable to a multiport transmission line, comprising the following steps: firstly, synchronously sampling a phase current of the local side and the opposite side of the line at a scheduled sampling rate, transmitting a sampling value of the phase current of the opposite side to the local side; secondly, calculating a phasor of each phase current of each side according to the sampling result; then forming the following criterion for current differential protection by split phase of the calculated result; finally, comparing the criterion in real time, if the criterion is met, judging as a fault in the multiport line area. The criterion of the invention not only ensures good brake characteristic of faults out of the transmission line area and high action sensitivity of faults in the area, but also well handles the defect that the biggest current side is not easy to select under the condition that the current ...

Battery charging circuit used for centralized meter reading terminal products

The present invention provides a battery charging circuit used for centralized meter reading terminal products, suitable for charging of nickel-hydrogen batteries, nickel cadmium batteries and lithium batteries, wherein a charging process of the lithium battery is divided into four processes, i.e., trickle charging, constant current charging, constant voltage charging and charging termination. By adopting a switching power supply scheme, the battery charging circuit of the present invention is high in charging efficiency, green and environment friendly, abundant in function, capable of completing battery charging with the optimal charging process, and capable of prolonging the service life of the battery. The battery charging circuit of the present invention is not only downwards compatible with a charged battery, but also upwards compatible with control systems at different complex grades, thus high application value is achieved.

New energy microgrid optimization operation method based on improved model predictive control

According to the new energy microgrid optimization operation method based on improved model prediction control provided by the invention, an improved Q learning algorithm is adopted to perform dynamic optimization on MPC control parameters, and the economic optimization operation effect of the microgrid in the rolling optimization operation process is improved. The method comprises the following steps: step 1, taking the minimum all-day energy consumption cost as an objective function, and performing optimization solution to obtain a micro-grid power plan curve as a reference target of MPC optimization operation; 2, introducing a Q learning algorithm, and constructing a Q value table; step 3, training the Q value table; 4, in the MPC periodic execution process, dynamic optimization is carried out on MPC control parameters, and iterative updating is carried out on the Q value table; 5, judging whether the MPC optimization decision is finished or not, and if not, skipping to the step 4 to ...

A control circuit for monopolizing become acquisition terminal and prevent remote control mistrip

The utility model relates to a control circuit for monopolizing become acquisition terminal and prevent remote control mistrip. The chip that restores to the throne connects CPU of system and first NAND gate respectively, and first NAND gate connects the second NAND gate, and the second NAND gate connects the RS flip -flop circuit, and the RS flip -flop circuit connects the 5th NAND gate, and the 5th NAND gate connects the D trigger, CPU's IO mouth forefront YK_EN1 connects first NAND gate and meets GND through pull down resistor R4, CPU's IO mouth second -line YK_EN2 connects the fourth NAND gate and meets VCC through pull -up resistance R3, the D trigger connects CPU's remote control output control pin, and the D trigger connects the optoelectronic isolation circuit, and the relay is connected through drive circuit to the optoelectronic isolation circuit. The chip that restores to the throne only is used in that system voltage is normal, could the output high level during system program ...

Tunnel junction foil gage device

The utility model provides a tunnel junction foil gage device, includes a basement, many to metal electrode, manyly encapsulates in pairs inside the basement metal electrode, and every two metal electrode tops to metal electrode are relative, and distance between the two metal electrode tops is 0.01nm -100nm, and every two right metal electrode tops are the vacuum state between and, and two metal electrode tail ends are equipped with the signal output wire and access to outside the basement. The utility model discloses compare with foil gage in the past, the structure is little, and the precision is high. It is how together integrated to metal electrode, make measured data more accurate. With tunnel current injection to the preparation of foil gage in, be used for perception micro deformation, realize nanometer deformation monitoring. Will the utility model discloses when pasting on, the object that reverses and shear bent at flexural, when the object took place to deform because of external ...

Control method and circuit for special transformer acquisition terminal to prevent remote control false tripping

The invention relates to a control method and circuit for a special transformer acquisition terminal to prevent remote control false tripping. According to the control method and circuit, when the terminal determines to emit tripping signals through a relay, the terminal can emit the tripping signals through the relay only by means of a complex logic sequence; high electric level signal output of a reset chip is adopted as a necessary condition of tripping signal emission; and the reset chip can output high electric level only when system voltage is normal and system program operates normally, and therefore, it can be ensured that no false tripping instructions are emitted.

Protective device starting component for double A/D sampling of electronic transformer in digital substation

The invention discloses a protective device starting component for double A/D sampling of an electronic transformer in a digital substation. The component is characterized in that an A/D sampling loop 1 is connected with a sampling value processing module 1 and then discriminates the action of a protection starting component and computes a protection function component; an A/D sampling loop 2 is connected with a sampling value processing module 2 and then discriminates the action of a repeated sampling starting component; and a device exit loop is allowed to open when the action signals of the protection starting component and the repeated sampling starting component act simultaneously, and at the same time, when the protection function component acts, the action exit signal of the device is output. By the method, the protective device can be effectively prevented from carrying out faulty action when one of the input double A/D data is abnormal.

Method for accelerating discrimination reclosing route selection based on two sides TV

The invention relates to a reclosing route selection acceleration discrimination method which is based on the TV at two sides. Circuit voltage is first sampled for two circuits corresponding to a central circuit breaker by the reclosing device, and the memory voltages of the two circuits are calculated; if the memory voltage is lower than the valve value, the circuit is malfunctioned, and corresponding circuit is accelerated. Non-malfunctioned circuit is avoided to be accelerated. By dynamic test certification and the method, the reclosing device corresponding to the central circuit breaker can successfully discriminate the malfunction circuit between two circuits, prevents a reclosing from accelerating the circuit which has no malfunction when malfunction occurs, avoids the misoperation of the circuit protection device in acceleration state which is caused by closing impulse current, and improves the operation stability of electric system.

Far infrared sorption water molecule producer

The utility model relates to a health care instrument, particularly to a far infrared sorption water molecule producer which is capable of improving air composition in hermetic small space, such as small rooms, offices, vehicles, and carriages. The utility model mainly comprises a cap container and a bottle container, wherein, the cap container is a hollow internal container chamber, and irregular communication approaches are arranged in the marginal surface of the internal container chamber; the bottle container is provided with a container chamber and a bottle mouth, and the cap container is inserted into the bottle mouth. Thus, blood circulation of a human body can be promoted without spending time for a special purpose.

A alternating current -direct current switches and button awakens control circuit up for monopolizing become acquisition terminal

The utility model discloses an alternating current -direct current switches and button awakens control circuit up for monopolizing become acquisition terminal, the chip D9 that restores to the throne connects NPN triode V34's base, and V34's collecting electrode connects PNP triode V33's collecting electrode, the CPU connects the chip D9's that restores to the throne WDI pin, and D9's the pin that restores to the throne connects NPN triode V14's base, and V14's collecting electrode connects V33's base, VCC and vbat are connected to the input of button K 4, and output signal connects PNP triode V54's projecting pole, and DC voltage 12V connects V54's base, voltage signal inserts NPN triode V40's base through resistance R129, R132, R139, and PMOS pipe D17's grid is connected to V40's collecting electrode, and vbat is connected in D17's drain electrode. The automatic switch -over between ac energisation and nickel -hydrogen battery dc supply has been realized, awaken dc supply up and be amenable ...

Method for protecting electric impedance element regulation by load self-adapting line

The invention relates to a load which monitors a line online, carries out a real-time calculation to the changes of the resistance of the load, combines with the fixed value range of all resistance sections with distance protection and phase selectors to distinguish a plurality of practical situations such as different malfunction types, system oscillation identification of oscillation detection elements, sending end or receiving end, etc., and adjusts the elements in resistance range: the protection can not only avoid a load state and but also can ensure the reaction capability to transition resistance. The method carries out the load resistance judgement and comparison by adopting the data windows of two frequency currents and is not affected by the transitional data window; therefore, the invention can fast judge the changes of the load, thus improving the performance of distance protection real-time monitoring load and ensuring no misoperation of distance protection in over load; furthermore ...

Automatic pressing plate inputting and retreating method based on secondary equipment self-inspection in intelligent substation

The invention provides an automatic pressing plate inputting and retreating method based on secondary equipment self-inspection in an intelligent substation. The automatic pressing plate inputting and retreating method based on secondary equipment self-inspection in the intelligent substation includes the following steps that firstly, self-inspection of work conditions of secondary equipment is carried out, the work conditions of the secondary equipment in the intelligent substation are monitored and self-inspected in real time, chip-level diagnosis is carried out, and an anomaly is analyzed and evaluated; secondly, the network link conditions of the secondary equipment are judged, the secondary equipment in the intelligent substation realizes information interaction through a GOOSE link and an SV link, and network positioning is carried out on the anomaly; thirdly, inputting and retreating of a pressing plate are carried out, the secondary equipment monitors information classification ...

Distance switching-in accelerating method self-adapting to oscillation

The invention discloses a distance switching-in accelerating method self-adapting to oscillation, which is characterized in that the method comprises the following steps: (1) calculation of impedance between sound phases; (2) calculation of impedance changing rates between the sound phases; (3) discrimination: whether the oscillation exists or not is discriminated according to the calculated impedance changing rates between the sound phases so as to discriminate whether the accelerating protection is opened or not; (4) switching-in accelerating logic: if the switching-in accelerating protection is opened, the impedance of an accelerating circuit is used for determining whether the switching-in acceleration is opened or not, and if the impedance of the accelerating circuit is in the range of the II stage, an acceleration is opened for rapidly cutting faults off; if the switching-in accelerating discrimination in step (3) is not opened, although the impedance of the accelerating circuitis ...

Current transformer saturation detecting technology based on phase comparing method

Distance switching-in accelerating method self-adapting to oscillation

The invention discloses a distance switching-in accelerating method self-adapting to oscillation, which is characterized in that the method comprises the following steps: (1) calculation of impedancebetween sound phases; (2) calculation of impedance changing rates between the sound phases; (3) discrimination: whether the oscillation exists or not is discriminated according to the calculated impedance changing rates between the sound phases so as to discriminate whether the accelerating protection is opened or not; (4) switching-in accelerating logic: if the switching-in accelerating protection is opened, the impedance of an accelerating circuit is used for determining whether the switching-in acceleration is opened or not, and if the impedance of the accelerating circuit is in the range of the II stage, an acceleration is opened for rapidly cutting faults off; if the switching-in accelerating discrimination in step (3) is not opened, although the impedance of the accelerating circuitis ...

Forward sequence direction quadrangle impedance relay applied for serial supplementary line

This invention relates to a positive-sequence direction quadrangle impedance relay formed by combining positive-sequence dirdction elements and offset character quadrangle impedance elements used in serial-compensating circuit characterizing that the resistance offset of the offset character quadrangle impedance element is R'=min(0.5RZD, 0.5ZZD), when serial-compensation capacitance appears in the positive exit, the reactance offset is X'=XC, if not, it is X'=min(0.5 Omega, 0.5ZZD), and the polarized voltage of the positive direction element is U'1=U1x|U1/Un|+Zx I, when reverse current may appear to the circuit, compensation is carried out and its impedance is: XC-ZS Подробнее

Judging method for transient and permanent faults of transmission line with parallel reactance

The invention relates to a judging method for transient and permanent faults of a transmission line with parallel reactance. The method comprises the following steps: 1) calculation of difference voltage, conducting difference calculation on sampling values of jumping-phase recovery voltage by taking 20ms or integral multiple thereof as intervals; 2) cumulative mean of difference voltage, carryingout cumulative mean of at least two cycles on the differentiated voltage; 3) judgment of fault types: if the difference voltage of cumulative mean is higher than a voltage threshold, the fault is a transient fault; if not, the fault is a permanent fault. The judging method can effectively identify transient and permanent faults, is free from the effect of line length, and is suitable for variousconditions of one end with parallel reactance, both ends respectively with parallel reactance, and line middle part with parallel reactance.

Distributed bus protection device based on HSR

The invention discloses a distributed bus protection device based on an HSR. Each bus connection gap is provided with one gap unit, each gap unit is provided with two kilomega Ethernet ports so that sample data and switching value data of the gap can be shared by other gaps through the Ethernet ports, and all the gap units are connected through a bi-directional ring topological structure in an HSR mode. By the adoption of the HSR technology and flange plate bypasses, bus protection reliability is improved; because all the gaps are uniformly configured, expansibility is strong; because each distributed bus protection gap can serve as a device independently and can be integrated with a local line protection device and other devices, space is saved, and data streams are optimized.

A tunnel junction dynamometry device

The utility model provides a tunnel junction dynamometry device, including a shell 1, refill 2, metal electrode 3, miniature singlechip 4, refill 2, metal electrode 3, miniature singlechip setting is at a shell 1, the encapsulation of two metal electrode 3 is inside the refill, two metal electrode 3 tops are relative, distance between the two metal electrode 3 tops is 0.01nm-100nm, between reaching, two metal electrode 3 tops are the vacuum state, two metal electrode 3 tail ends are equipped with the wire and connect miniature singlechip 4, there is a metal electrode 3 tail end to arrange the nib department of refill 2 in among two metal electrode 3. Adopt the utility model discloses when writing, along with the size that the nib was exerted oneself, corresponding deformation can take place for the refill, and this can result in the distance between two electrodes to change, and the tunnel current also can correspond the change with it, and the power of equidimension does not correspond ...

Method for generating industrial control honeypot telemetering mimicry data through electric power IED equipment

The invention discloses a method for generating industrial control honeypot telemetering mimicry data by electric power IED (Intelligent Electronic Device) equipment, which comprises the following steps of: deploying an industrial control honeypot function on a communication board card or a functional board card of the electric power IED equipment; through mimicry data generation, according to complexity of a network environment where the electric power IED is located and synchronous implementation of destructive attack and data stealing of an attacker on a network, a network state vector of an operation environment where the electric power IED is located is calculated based on a Markov chain; according to the electric power IED equipment network state vector and the telemetering basic data based on the electric power specification, the more reasonable telemetering mimicry data is obtained through the network state estimation and the operation condition estimation of the IED equipment, ...

AC/DC switchover and key waking control circuit for acquiring terminal of specific power transformer

The invention discloses an AC/DC switchover and key waking control circuit for an acquiring terminal of a specific power transformer. A reset chip D9 is connected with a base electrode of an NPN triode V34; a collector electrode of V34 is connected with a collector electrode of a PNP triode V33; a CPU is connected with a WDI pin of the reset chip D9; a reset pin of D9 is connected with a base electrode of an NPN triode V14; a collector electrode of V14 is connected with a base electrode of V33; an input end of a key K4 is connected with VCC and Vbat, and an output signal is connected with an emitting electrode of a PNP triode V54; DC voltage 12V is connected with a base electrode of V54; a voltage signal is accessed to a base electrode of the NPN triode V40 via resistors R129, R132 and R139; a collector electrode of V40 is connected with a grid electrode of a PMOS tube D17, and a drain electrode of D17 is connected with the Vbat. The automatic switchover between AC power supply and DC power ...

Tunnel junction ear bone sensor device

The utility model provides a tunnel junction ear bone sensor device, includes bottom plate, two metal electrode, keeps apart the air material, and two metal electrode are above attached to the bottom plate, keep apart on the air material covers two metal electrode on the bottom plate, and two metal electrode keep apart with the air, and two metal electrode tops are relative, and the distance is 0.01nm-100nm between two metal electrode tops, and two metal electrode tail ends are equipped with outer guide line respectively and draw forth outside the isolation air material. The utility model has the advantages of simple and reasonable structure, it is easy to manufacture, introduces tunnel effect the preparation of ear bone sensor, makes the device with it and comes human interior pulse of perception and blood flow etc. Perhaps directly is used for the sound in the perception external world, and air current etc. All are feasible. Will the utility model discloses attached in human forehead ...

Method for accelerating discrimination reclosing route selection based on two sides TV

Tunnel junction metal stock temperature detect appearance device

The utility model relates to a tunnel junction temperature detector device specifically is a tunnel junction metal stock temperature detect appearance device, including basement, metal electrode, metal stock, two metal electrode seal inside the basement, and two metal electrode tops are relative, and the distance between the top is 0.01nm -100nm, and two metal electrode top parts are the vacuum state, and two metal electrode tail ends are equipped with outer guide line, and the basement is glued and is sticked on the metal stock. The metal electrode top is the needle point shape. Metal electrode's material is platinum, tungsten, iridium or for the alloy material of platinum, tungsten, iridium. The utility model discloses rational in infrastructure simple, manufacture easy, through the utility model discloses, expression that can be effective is the still size of temperature nearby at a distance no matter, so long as the pole equal measurable quantity of distance in one's power, has so also ...

Fault phase-selecting method in oscillation of high-voltage line protection

The present invention discloses a fault phase-selecting method in the oscillation of high-voltage line protection, which is characterized in that the fault phase-selecting method comprises the following steps: (1) calculation of the impedance changing rate of each circuit; (2) discrimination of the impedance change of each circuit; (3) subarea phase selection in the oscillation: the subarea phase selection in the oscillation is inputted when zero-sequence current and negative-sequence current are large, and only subareas and corresponding circuits with constant impedance measuring values can be selected; (4) impedance phase selection in the oscillation: discrimination is carried out according to the impedance changing rate of each circuit, if the impedance changing rate of only one circuit is small, the circuit is directly selected; if the impedance changing rates of a plurality of circuits are small, the impedance phase selection is independently carried out on the circuits; if the impedance ...

Fault phase-selecting method in oscillation of high-voltage line protection

The invention discloses a fault phase-selecting method in the oscillation of high-voltage line protection, which is characterized in that the fault phase-selecting method comprises the following steps: (1) calculation of the impedance changing rate of each circuit; (2) discrimination of the impedance change of each circuit; (3) subarea phase selection in the oscillation: the subarea phase selection in the oscillation is inputted when zero-sequence current I<0> and negative-sequence current *2 are large, and only subareas and corresponding circuits with constant impedance measuring values can be selected; (4) impedance phase selection in the oscillation: discrimination is carried out according to the impedance changing rate of each circuit, if the impedance changing rate of only one circuitis small, the circuit is directly selected; if the impedance changing rates of a plurality of circuits are small, the impedance phase selection is independently carried out on the circuits; if the impedance ...

A current differential protection judgement method applicable to multi-end power input line

The invention relates to a criterion method for current differential protection, applicable to a multiport transmission line, firstly, phase current of the local side and the opposite side of the line are subject to synchronous sampling at a scheduled sampling rate, the sampling value of the phase current of the opposite side is transferred to the local side; secondly, the phasor of each phase current of each side is calculated according to the sampling results; then the following criterion for current differential protection is formed by split phase of the calculated results.

Traveling-wave differential protection method suitable for series capacitor compensation circuit

The invention discloses a traveling-wave differential protection method suitable for a series capacitor compensation circuit. The method comprises the steps: 1) current calculation under a mold domain, calculating mold currents im and in flowing into a series capacitor device from onside and offside; 2) establishment of differential equation; 3) resolution of differential currents, utilizingthe reverse transformation of phase molds to solve vectors icd of the differential currents of each fault phase and each non-fault phase; 4) action judgment of a differential relay: utilizing the fault-phase action amount as braking, and adding an appropriate fixing threshold. The invention can effectively solve the effect of capacitor current on differential protection of long-distance transmission lines, can be well suitable for the series capacitor compensation circuit, and enhances the sensitivity of differential protection.

Traveling-wave differential protection method suitable for series capacitor compensation circuit

The invention discloses a traveling-wave differential protection method suitable for a series capacitor compensation circuit. The method comprises the steps: 1) current calculation under a mold domain, calculating mold currents im and in flowing into a series capacitor device from onside and offside; 2) establishment of differential equation; 3) resolution of differential currents, utilizing the reverse transformation of phase molds to solve vectors icd of the differential currents of each fault phase and each non-fault phase; 4) action judgment of a differential relay: utilizing the fault-phase action amount as braking, and adding an appropriate fixing threshold. The invention can effectively solve the effect of capacitor current on differential protection of long-distance transmission lines, can be well suitable for the series capacitor compensation circuit, and enhances the sensitivity of differential protection.

Differential protection method for preventing false operation during current disappearance

The invention relates to a differential protection method for preventing false operation during current disappearandce, which comprises the following steps: preparing to trip according to the differential protection action after a protection device starts for 60ms; then, using a waveform similarity criterion to compute waveform similarity coefficients computed in a short window data of a differential action element 20ms before; if the waveform similarity coefficient values in the data window are all less than 0.2, tripping immediately; and if the condition that the waveform similarity coefficient values in the data window are greater than 0.2 exists, delaying differential protection for 20ms, and triggering port if the fault does not disappear. The method is based on a least square filtering principle, compares whether a target alternating quantity is the normal system waveform or distorted waveform according to the waveform similarity coefficients, and does not differentiate the faultstarting ...