Hilbert filter used for power computing

The present invention relates to a Hilbert filter for electrical energy measuring belonging to the technical field of electrical energy measuring, which comprises an input port selector, a data selector to select amongst a serial current signal, a voltage signal and a multiplication result according to control time sequence of a controller, an address generator to generate a memory read-write operation address based on coding, a controller to respectively generate a control signal according to calculation time sequence of each two-step joint, a memory to store intermediate calculation data, an output port selector to receive a current and a voltage signal output by the memory and convert the received current and voltage signal into parallel current and voltage flows for output, a multiplication accumulator to multiply data output the memory and work out a multiplication result and a coefficient generator to generate each two-step coefficient for the filter according to the controller time ...

Phase compensation method for multi-channel analog to digital converted signals

The invention relates to a phase compensation method for multi-channel analog to digital converted signals and belongs to the technical field of hybrid signal processing. The method comprises the following steps of: inputting the original signal of each channel, transmitting the signals through channels, performing phase delay on the signal input into each channel, obtaining phase delay signals, performing analog to digital conversion on the phase delay signals to obtain digital discrete signals, adding phase delays into the digital discrete signals when the phase delays of the digital discrete signals of any two channels in the channels meet the following equation, and allocating the down-sampling time of a down-sampling filter of each channel respectively according to the relationship. The phase compensation method of the invention realizes the same phase adjustment range, phase adjustment precision and software phase adjustment ability as the phase compensation method using a digital ...

Electric energy compensation method based on active and reactive power vector

Method for measuring fundamental frequency

The invention relates to a measurement method of fundamental frequency and belongs to the field of composite signal processing, and the method comprises the following steps: the method acquires digital signals v(k) by implementing the input signal sampling with sampling frequency fs, which is N times an initial setting value f0 of the fundamental frequency f1, and constructs two orthogonal signals with the frequency equal to an ideal value of the fundamental frequency of the input signal; the invention acquires a signal for low-pass filter processing by implementing multiplication between the two orthogonal signals and the input signal v(k), filters the high-frequency part of the signal and acquires the orthogonal signals which are related to the input signal, and then the method acquires the phase position information in a time k which is related to the input signal through the arctangent computation, acquires the signal fundamental frequency by computing and transforming the difference ...

Electric energy compensation method based on active and reactive power vector

The present invention relates to an electric energy measurement compensating method based on the active vector and the reactive vector, and belongs to the electric energy measurement technology filed. When the electric energy measurement system is a three-phase four-wire system, in case the first phase is of malfunction phase, then the voltage of the second phase or the voltage of the third phase and the current of the first phase can be used. The active power and the reactive power of the first phase can be calculated, using the calculated active power and the calculated reactive power can calculate the actual active power of the first phase by the compensating method. When the electric energy measurement system is a three-phase three-wire system, the compensating procedure is similar to the above procedure. The present invention can calculate the active power and the reactive power by using the replacement of the voltage of the other normal phases when the voltage lacks phases, can recover ...

Digital synchronous sampling method

The invention relates to a digital synchronous sampling method, which belongs to the field of D/A mixed signal processing. The method comprises the following steps of: setting a sampling frequency fsto M*N*f0, sampling an input signal with a frequency fi according to the sampling frequency fs, wherein f0 is the frequency theoretical value of the input signal; measuring the frequency of the inputsignal; and subjecting the sampled signal to lower decimation filtering at a decimation position p and a decimation rate M' by a cascade comb decimation filter manner according to the frequency measurement result to an input signal with a sampling frequency and a frequency of fi after decimation satisfying the synchronous sampling relationship. The invention has the advantages of less calculationamount, easy implementation, accuracy synchronization and good practicality.

Method for preventing shunt running in electrical energy measurement

The invention relates to an anti-creep method of electricity meter and belongs to the technical field of electricity energy measurement; current signals used to judge creep are selected from the current signals input from an electricity grid; the current signals are transformed into digital signals; after being implemented gain amplification, the digital signals which exceeds the measurement scope of an electricity energy system are implemented saturation processing and bandpass filtering; after being implemented bandpass filtering, the digital signals are implemented auto-correlation multiplication, implemented lowpass filtering and figured out square root; therefore, the effective values of the current signals which are used to judge the creep are acquired; the effective values are implemented backlash judgment; the electricity energy measurement system is controlled to measure the electricity energy according to the result of backlash judgment. The invention adopts the current as judgment ...

Hilbert filter used for power computing

Method for preventing shunt running in electrical energy measurement

Harmonic energy metering method

The present invention provides a harmonic electric energy measuring method, and belongs to the electric energy measuring technology filed. The method separates the basic wave coming from the signal of the voltage and the current of the power grid by a low-pass filter, separates the harmonic signal by a high-pass filter, then gets basic wave current and basic wave voltage as well as total harmonic current and total harmonic voltage; separates the total harmonic current and the total harmonic voltage to obtain a sub-harmonic current and a sub-harmonic voltage which need to be measured by an infinite impulse responding belt passing filter method; obtains different sub-harmonic current and sub-harmonic voltage of different times according to different harmonic frequencies to be measured; calculates various date of the power grid according to the basic wave current signal and the basic wave voltage signal. The spending of the present invention is less than that of the traditional rapid Fourier ...

Harmonic energy metering method

Digital synchronous sampling method

The invention relates to a digital synchronous sampling method, which belongs to the field of D/A mixed signal processing. The method comprises the following steps of: setting a sampling frequency fs to M*N*f0, sampling an input signal with a frequency fi according to the sampling frequency fs, wherein f0 is the frequency theoretical value of the input signal; measuring the frequency of the input signal; and subjecting the sampled signal to lower decimation filtering at a decimation position p and a decimation rate M' by a cascade comb decimation filter manner according to the frequency measurement result to an input signal with a sampling frequency and a frequency of fi after decimation satisfying the synchronous sampling relationship. The invention has the advantages of less calculation amount, easy implementation, accuracy synchronization and good practicality.

Method for measuring fundamental frequency

The invention relates to a measurement method of fundamental frequency and belongs to the field of composite signal processing, and the method comprises the following steps: the method acquires digital signals v(k) by implementing the input signal sampling with sampling frequency fs, which is N times an initial setting value f0 of the fundamental frequency f1, and constructs two orthogonal signalswith the frequency equal to an ideal value of the fundamental frequency of the input signal; the invention acquires a signal for low-pass filter processing by implementing multiplication between thetwo orthogonal signals and the input signal v(k), filters the high-frequency part of the signal and acquires the orthogonal signals which are related to the input signal, and then the method acquiresthephase position information in a time k which is related to the input signal through the arctangent computation, acquires the signal fundamental frequency by computing and transforming the differenceof ...