CN103869162B - Dynamic signal phasor measurement method based on time domain quasi-synchronization - Google Patents

Dynamic signal phasor measurement method based on time domain quasi-synchronization Download PDF

Info

Publication number
CN103869162B
CN103869162B CN201410078765.7A CN201410078765A CN103869162B CN 103869162 B CN103869162 B CN 103869162B CN 201410078765 A CN201410078765 A CN 201410078765A CN 103869162 B CN103869162 B CN 103869162B
Authority
CN
China
Prior art keywords
quasi
frequency
time domain
signal
phasor measurement
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201410078765.7A
Other languages
Chinese (zh)
Other versions
CN103869162A (en
Inventor
温和
滕召胜
王康
孟卓
黎福海
郭斯羽
金冉
戴慧芳
沈凤文
张海焕
吴禹
李峰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hunan University
Original Assignee
Hunan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hunan University filed Critical Hunan University
Priority to CN201410078765.7A priority Critical patent/CN103869162B/en
Publication of CN103869162A publication Critical patent/CN103869162A/en
Application granted granted Critical
Publication of CN103869162B publication Critical patent/CN103869162B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The invention discloses a dynamic signal phasor measurement method based on time domain quasi-synchronization. The dynamic signal phasor measurement method based on the time domain quasi-synchronization comprises the following steps: estimating the fundamental wave frequency of a sampled signal by a time domain quasi-synchronization sampling algorithm; carrying out time domain quasi-synchronization on the sampled signal by the estimated value of the fundamental wave frequency; reconstructing a quasi-synchronization sampling sequence by Newton interpolation; carrying out frequency domain analysis on the reconstructed quasi-synchronization sampling sequence by FFT (fast Fourier transform) to obtain a dynamic signal phasor measurement result. According to the method, the influence on the measurement precision of the traditional phasor measurement method by frequency spectrum leakage caused by nonsynchronous sampling is avoided. The computation complexity of the dynamic signal phasor measurement method based on the time domain quasi-synchronization is smaller than the computation complexity of the traditional phasor measurement method based on the discrete Fourier transform, and the dynamic signal phasor measurement method based on the time domain quasi-synchronization is easy to realize in an embedded system.

Description

One kind is based on time domain quasi synchronous Dynamic Signal phasor measurement method
Technical field
The present invention relates to signal phasor measurement field, specifically one kind are based on time domain quasi synchronous Dynamic Signal phasor measurement Method.
Background technology
With widely using of the nonlinear-loads such as power electronic equipment, semiconductor device, power quality problem layer goes out not Thoroughly.How measuring and to analyze the practical situation of power system in real time, thus improving the quality of power supply, having become as power train in recent years Emphasis in system research field and focus.
At present, in power system, voltage and current is all the variations per hour doing sinusoidal variations in time, all can use phasor representation. But, IEEE Standard 1344-1995 define phasor premise be under steady state conditions, a reactor, that is, the amplitude of signal, frequency and Phase angle all keeps constant, and under rated frequency, the instantaneous measure of phase angle keeps constant with absolute reference time relatively.But In practical application, when signal frequency deviates rated frequency, phase angle changes with frequency, thus introducing error it is difficult to obtain accurately Value of calculation.
Existing phasor measurement algorithm mainly has cross zero detecting method, discrete Fourier transform (DFT) method etc..Cross zero detecting method Be compare intuitively a kind of synchronous phasor measuring method it is only necessary to by the zero crossing moment of tested power frequency component with sometime mark Standard compares and can draw phase angle difference;Cross zero detecting method principle is simple, it is easy to accomplish, but its precision is not high, and be easily subject to harmonic wave, make an uproar The impact of sound component.When electrical network medium frequency no offsets, DFT algorithm can accurately measure amplitude and the phase place of signal, and its Computational accuracy is not affected by Constant Direct Current component and integer harmonic component;But when mains frequency offsets, due to asynchronous The spectrum leakage that sampling causes, the precision of phasor measurement can decline rapidly.
For this reason, a kind of Dynamic Signal phasor measurement method studying high accuracy is ensureing power system safety and stability operation Aspect is significant.
Content of the invention
The invention provides a kind of be based on time domain quasi synchronous Dynamic Signal phasor measurement method, it is to avoid non-synchronous sampling The impact to existing phasor measurement method certainty of measurement for the spectrum leakage causing;Measured based on time domain quasi synchronous Dynamic Signal phase Quantity algorithm computational complexity is less than the existing phasor measurement algorithm based on discrete Fourier transform, and quasi synchronous based on time domain Dynamic Signal phasor measurement algorithm is easy to realize in embedded systems.
For solving above-mentioned technical problem, solution proposed by the present invention is:Estimated using time domain quasi-synchro sampling algorithm The fundamental frequency of sampled signal, does time domain plesiochronousization using fundamental frequency estimated value to sampled signal, by Newton interpolating method Reconstruct quasi-synchro sampling sequence, carries out frequency-domain analysiss using FFT to the quasi-synchro sampling sequence of interpolation reconstruction, obtains Dynamic Signal Phasor measurement result.
Technical scheme is as follows:
One kind is based on time domain quasi synchronous Dynamic Signal phasor measurement method, comprises the following steps:
Step one:Electric power signal is sampled, individually sampled signal is saved as crude sampling sample after sampling, with When to sampled signal add wave filter, to filter harmonic wave and noise jamming;
Step 2:Adopt quasi-synchro sampling algorithm to estimate fundamental frequency the sampled signal after filtered process, obtain base Wave frequency estimated value fg
Step 3:Using the frequency estimation f obtaining in step 2gAnd sampling number N calculates in the signal period Obtain quasi-synchro sampling cycle λ, with λ as step-length, using Newton interpolating method to the discrete sequence in sample original in step one Row do time domain plesiochronousization and process, and interpolation reconstruction obtains quasi-synchro sampling sequence;
Step 4:To the quasi-synchro sampling sequence obtaining in step 3, a signal period is intercepted using rectangular window, carries out FFT spectrum is analyzed, and obtains the frequency domain information of signal, and calculates frequency, amplitude and the phase parameter of electric power signal, obtains dynamic Signal phasor measurement result.
Described method, the selection rule of step one median filter is:
Choose triangular self-convolution window digital band pass FIR filter, lower stopband edge frequency is 40Hz, lower passband edge frequency For 46Hz, upper passband edge frequency is 54Hz, and upper stopband edge frequency is 60Hz, passband ripple 0.01, stopband ripple 0.1.Its In, the method for designing of triangular self-convolution window digital band pass FIR filter is:First, according to the finger to stopband attenuation and intermediate zone Mark requires, and selects triangular self-convolution window, and estimates length of window;Secondly, the frequency response function of construction ideal digital wave filter, And ideal unitary impulse response is obtained according to ideal frequency response function;Finally, to impulse response function plus triangular self-convolution window Obtain design result.
Described method, in step 2, quasi-synchro sampling algorithm parameter selection rule is:
Single iteration points D is 64, and iterationses P is 5.
Mode below by way of theoretical derivation illustrates to the technique effect that the present invention reaches.
In time domain, continuous harmonic signal may generally be expressed as following form
u ( t ) = Σ k A k s i n ( 2 π f k t + θ k ) - - - ( 1 )
In formula, k is overtone order, represents fundamental wave during k=1;AkFor kth subharmonic amplitude;T is the time;F is fundamental signal Frequency;θkInitial phase angle for kth subharmonic.
Ignore the quantization error in analog-digital conversion process, and the various random error in measurement process, using sampling frequency Rate is fsAnalysis System for Power Quality obtain NcIndividual sample
u ( n ) = Σ k A k s i n ( 2 π k n f / f s + θ k ) - - - ( 2 )
In formula, n is more than or equal to 0 and to be less than or equal to Nc- 1 integer.
In order to carry out fundamental frequency estimation, filtered using the sample that triangular self-convolution window band filter obtains to sampling Ripple is processed, and filters higher hamonic wave, obtains signal as follows
U (n)=A1sin(2πnf/fs1) in (3) formula, A1For fundamental voltage amplitude;θ1For fundamental wave initial phase angle.
Quasi-synchro sampling algorithm recurrence formula is as follows
X a 1 = 2 Σ i = i 0 D + i 0 ρ i Σ i = i 0 D + i 0 ρ i u ( t i ) cos ( 2 π i D ) - - - ( 4 )
X b 1 = 2 Σ i = i 0 D + i 0 ρ i Σ i = i 0 D + i 0 ρ i u ( t i ) s i n ( 2 π i D ) - - - ( 5 )
In formula:The subscript " 1 " of " X " represents the 1st quadrature computing;D be defined synchronous sampling algorithm single iteration points, D= 64;ρiFor the corresponding weight coefficient of numerical quadrature formula, for complexification compound trapezoidal integeration, ρ0D=0.5, ρ12=...= ρD-1=1.
Estimate to obtain phase difference θ in the Δ t time, then signal fundamental frequency using quasi-synchro sampling algorithm recurrence formula Estimated value fgFor
f g = ω 2 π = Δ θ 2 π Δ t - - - ( 6 )
In formula, ω represents fundamental wave angular frequency, and Δ θ represents fundamental wave phase angle difference, and Δ t represents the corresponding time difference of Δ θ.
According to the quasi-synchronous algorithm parameter of patent requirements of the present invention, estimated frequency error is less than 3 × 10-10Hz.Using (6) Frequency estimation, the original sampled signal sample in step one is carried out with time domain plesiochronousization, interpolation reconstruction obtains plesiochronous Sample sequence.Interpolation polynomial is
P (x)=u [x0]+u[x0,x1](x-x0)+L+u[x0,x1,L,xm](x-x0)L(x-xm-1) (7)
In formula, x is sampled signal time interval, and subscript m represents m-th sampling time interval, and u [...] is difference coefficient, u [x0]=u (x0), k jump business is
u [ x i , x i + 1 , L , x i + k ] = u [ x i + 1 , L , x i + k ] x i + k - x i - u [ x i , L , x i + k - 1 ] x i + k - x i - - - ( 8 )
With rectangular window, is intercepted to interpolation reconstruction signal one signal period, carry out frequency-domain analysiss using FFT, in signal spectrum Middle searching harmonic wave corresponding peak value spectral line, by analyzing frequency, phase place and the magnitude parameters of peak value and then acquisition electric power signal, Complete the phasor measurement of Dynamic Signal.
In sum, of the present invention a kind of it is based on time domain quasi synchronous Dynamic Signal phasor measurement method, it is to avoid non- Under synchronized sampling, spectrum leakage and fence effect that FFT causes, and the method computational complexity is less than traditional windowed interpolation Fft algorithm is it is easy to realize in embedded systems.
The invention will be further described below in conjunction with the accompanying drawings.
Brief description
Fig. 1 is the program flow diagram realized in the present invention based on time domain quasi synchronous Dynamic Signal phasor measurement;
Fig. 2 is quasi-synchro sampling algorithm iteration schematic diagram in the present invention;
Fig. 3 is Newton interpolating method reconfiguration principle figure in the present invention.
Specific embodiment
The program circuit that the present invention realizes based on the quasi synchronous harmonic analysis and measurement method of time domain is as shown in Figure 1.
As shown in figure 1, the first step, using Analysis System for Power Quality, the signal of input is sampled, obtain NcIndividual sample This, NcFor natural number, fsFor sample frequency.
Second step, with triangular self-convolution window band filter to the N collectingcIndividual sample is filtered denoising.Three The parameter of angle self-convolution window band filter is:Triangular self-convolution window band filter, lower stopband edge frequency is 40Hz, lower logical Belt edge frequency is 46Hz, and upper passband edge frequency is 54Hz, and upper stopband edge frequency is 60Hz, passband ripple 0.01, stopband Ripple 0.1.
3rd step, is iterated to the signal after filtering and noise reduction using quasi-synchro sampling algorithm, estimates the base of measured signal Wave frequency, obtains fundamental frequency fg, wherein quasi-synchro sampling single iteration points D is 64, and iterationses P is 5.Frequency Estimation Comprise the following steps that:
In t1The P*D+1 dis-crete sample values in moment are iterated, as shown in Fig. 2 the fundamental wave respectively obtaining P iteration is real Portion XJ aWith fundamental wave imaginary part XJ b, then t1Fundamental phase θ in moment1For
θ 1 = a r c t a n X a J X b J - - - ( 9 )
T can be obtained in the same manner2Fundamental phase θ in moment2, then fundamental frequency estimated value fgFor
f g = ω 2 π = Δ θ 2 π Δ t = θ 2 - θ 1 2 π ( t 2 - t 1 ) - - - ( 10 )
In formula, ω represents fundamental wave angular frequency, and Δ θ represents fundamental wave phase angle difference, and Δ t represents the corresponding time difference of Δ θ.
4th step, using fundamental frequency estimated value fg, using principle shown in Fig. 3, time domain is done to crude sampling sample plesiochronous Change is processed, the signal sequence u under the conditions of interpolation reconstruction synchronized samplingi(k).
5th step, with sequence u to interpolation reconstruction for the rectangular windowiK () is blocked, intercept the discrete sequence of a signal period Row ui(ki)(ki=0,1 ..., N-1).Carry out FFT spectrum analysis to intercepting sequence, obtain.
Y ( k i ) = A 0 2 j e jθ 0 W R ( 2 π ( k i - k 0 ) / N ) - - - ( 11 )
In formula, k0=fgN/fs;WRK () is rectangular window frequency spectrum.
6th step, to Y (ki) be analyzed, in Y (ki) the middle searching corresponding peak value of each harmonic, divided by analyzing peak value Huo Qu not the frequency of each harmonic, amplitude and phase place.
So far, complete the measurement of Dynamic Signal phasor, the method for the present invention is applicable to electric power signal fundamental wave frequency deviation The situation of no frequency deviation.
Method provided by the present invention is below applied to carry out emulation experiment, to verify the reliability of method provided by the present invention Property.
Produce an emulation signal using MATLAB, signal model is as follows
Y (t)=220sin (2 π f0t+θ1)+2.3936sin(6πf0t+θ3)+1.3442sin(10πf0t+θ5) (12) formula In, fundamental frequency f0Value in 49.5~50.5Hz, step-length 0.1Hz;Fundamental voltage amplitude A1For 220V, phase theta1=π/3rad;3 Subharmonic and 5 order harmonic components amplitudes are respectively A3=2.3936V, A5=1.3442V, phase place is respectively θ3=π/4rad, θ5= π/6rad.
Using sample frequency fsThe Analysis System for Power Quality collection N of=3200Hzc=512 samples are analyzed.Emulation Parameter value is as follows
Quasi-synchro sampling algorithm:Single iteration points D is 64, and iterationses P is 5
Newton interpolating method:Interpolation is counted as 11 points
FFT frequency-domain analysiss:Using rectangular window, the fft analysis of N=64 points
As shown in table 1, in table 1, aE-b represents a × 10 to simulation result-b.
Referring to table 1, when frequency fluctuation is ± 0.5Hz, electric power signal fundamental frequency estimates that absolute error is respectively less than 8.70E-10, fundamental voltage amplitude absolute error is respectively less than 4.60E-9, and fundamental phase absolute error is respectively less than 5.90E-11;3 subharmonic Amplitude Estimation error is respectively less than 1.10E-08, and 3 subharmonic phase angle absolute errors are respectively less than 3.20E-09;5 subharmonic Amplitude Estimation Error is respectively less than 9.80E-09, and 5 subharmonic phase angular estimation absolute errors are respectively less than 2.50E-08.Therefore, demonstrate institute of the present invention The feasibility of Dynamic Signal phasor measurement method providing and correctness.
Table 1 carries out the result of emulation experiment using method provided by the present invention

Claims (2)

1. a kind of time domain quasi synchronous Dynamic Signal phasor measurement method that is based on is it is characterised in that comprise the following steps:
Step one:Electric power signal is sampled, individually sampled signal is saved as crude sampling sample after sampling, simultaneously right Sampled signal adds wave filter, to filter harmonic wave and noise jamming, then the sampled signal after filtered process is carried out step 2 Process;
Step 2:Adopt quasi-synchro sampling algorithm to estimate fundamental frequency the sampled signal after filtered process, obtain fundamental wave frequency Rate estimated value fg
Step 3:Using fundamental frequency estimated value f obtaining in step 2gAnd sampling number N calculates in the signal period To quasi-synchro sampling cycle λ, with λ as step-length, using Newton interpolating method to the discrete serieses in sample original in step one Do time domain plesiochronousization to process, interpolation reconstruction obtains quasi-synchro sampling sequence;
Step 4:To the quasi-synchro sampling sequence obtaining in step 3, a signal period is intercepted using rectangular window, carries out FFT Spectrum analyses, obtain the frequency domain information of signal, and calculate frequency, amplitude and the phase parameter of electric power signal, are dynamically believed Number phasor measurement result;
The selection rule of step one median filter is:
Choose triangular self-convolution window band filter, lower stopband edge frequency is 40Hz, lower passband edge frequency is 46Hz, upper logical Belt edge frequency is 54Hz, and upper stopband edge frequency is 60Hz, passband ripple 0.01, stopband ripple 0.1.
2. method according to claim 1 it is characterised in that in step 2 quasi-synchronous algorithm parameter selection rule be:
Single iteration points D is 64, and iterationses P is 5.
CN201410078765.7A 2014-03-05 2014-03-05 Dynamic signal phasor measurement method based on time domain quasi-synchronization Active CN103869162B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410078765.7A CN103869162B (en) 2014-03-05 2014-03-05 Dynamic signal phasor measurement method based on time domain quasi-synchronization

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410078765.7A CN103869162B (en) 2014-03-05 2014-03-05 Dynamic signal phasor measurement method based on time domain quasi-synchronization

Publications (2)

Publication Number Publication Date
CN103869162A CN103869162A (en) 2014-06-18
CN103869162B true CN103869162B (en) 2017-02-08

Family

ID=50907913

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410078765.7A Active CN103869162B (en) 2014-03-05 2014-03-05 Dynamic signal phasor measurement method based on time domain quasi-synchronization

Country Status (1)

Country Link
CN (1) CN103869162B (en)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104181389B (en) * 2014-07-02 2017-02-15 中国农业大学 Phasor measurement method in electric-power system
CN104122443B (en) * 2014-08-04 2017-02-15 国家电网公司 Adjacent harmonic and inter-harmonic separation and measurement method under IEC (international electrotechnical commission) framework
CN104198872B (en) * 2014-09-29 2017-10-24 徐雪松 Online equipment for monitoring power quality and method
CN104407197B (en) * 2014-11-27 2017-06-27 湖南大学 A kind of method of the signal phasor measurement based on trigonometric function iteration
CN104459419A (en) * 2014-12-29 2015-03-25 国网四川省电力公司电力科学研究院 Measuring error compensation method and device for nonsynchronous periodic signal adoption
CN104898041A (en) * 2015-06-30 2015-09-09 绵阳市维博电子有限责任公司 Phase-sensitive rail signal detecting method and system
CN105388361B (en) * 2015-12-31 2018-01-23 武汉大学 Two-way interpolation synchronizes the FFT electric harmonic detection methods of sample sequence
CN106405229B (en) * 2016-08-30 2019-04-30 威胜集团有限公司 A kind of fundamental wave and harmonic wave electric energy gauging method
CN107085144B (en) * 2017-04-28 2019-08-20 珠海泰芯半导体有限公司 A kind of method of rapid survey Harmonious Waves in Power Systems
CN108362939B (en) * 2018-01-31 2020-06-23 成都泰格微波技术股份有限公司 Frequency domain parameter measuring method of linear frequency modulation signal
JP6649419B2 (en) * 2018-03-26 2020-02-19 ファナック株式会社 Encoder signal processing device and encoder
CN109507495B (en) * 2018-10-17 2020-12-15 华北水利水电大学 Variable-window-length quasi-synchronization grid-connected parameter measurement method
CN109632070B (en) * 2019-01-10 2020-11-24 东北大学 Digital array time domain quasi-synchronous calibration method based on Newton interpolation
CN110068729B (en) * 2019-04-22 2021-11-05 南京磐能电力科技股份有限公司 Signal phasor calculation method
CN110687377B (en) * 2019-10-12 2021-07-30 广东电网有限责任公司 Online monitoring data processing method and device for distributed energy system
CN112067887B (en) * 2020-09-09 2021-08-27 山东大学 Method for calculating phase quantity under condition of sampling value loss based on filter orthogonal characteristic

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5400366A (en) * 1992-07-09 1995-03-21 Fujitsu Limited Quasi-synchronous detection and demodulation circuit and frequency discriminator used for the same
EP1367794A2 (en) * 1998-01-30 2003-12-03 Matsushita Electric Industrial Co., Ltd. Modulation method and radio communication system
CN101915874A (en) * 2010-07-20 2010-12-15 北海市深蓝科技发展有限责任公司 Harmonic wave detection method based on Fourier transformation
CN102788901A (en) * 2012-08-14 2012-11-21 上海电器科学研究院 High accuracy synchronous dynamic phasor measurement method
CN103543335A (en) * 2013-10-30 2014-01-29 国家电网公司 Method for measuring synchronous phasor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5400366A (en) * 1992-07-09 1995-03-21 Fujitsu Limited Quasi-synchronous detection and demodulation circuit and frequency discriminator used for the same
EP1367794A2 (en) * 1998-01-30 2003-12-03 Matsushita Electric Industrial Co., Ltd. Modulation method and radio communication system
CN101915874A (en) * 2010-07-20 2010-12-15 北海市深蓝科技发展有限责任公司 Harmonic wave detection method based on Fourier transformation
CN102788901A (en) * 2012-08-14 2012-11-21 上海电器科学研究院 High accuracy synchronous dynamic phasor measurement method
CN103543335A (en) * 2013-10-30 2014-01-29 国家电网公司 Method for measuring synchronous phasor

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
基于准同步采样的电力系统谐波与间谐波在线检测方法研究;周峰;《中国博士学位论文全文数据库(电子期刊)》;20121015(第10期);论文第3章第32页最后第1段-第33页第8段 *
广域测量系统中相量算法的研究;姜桂秀;《中国优秀硕士学位论文全文数据库(电子期刊)》;20060715(第7期);摘要和论文第5章第25页第1段-第30页第3段 *

Also Published As

Publication number Publication date
CN103869162A (en) 2014-06-18

Similar Documents

Publication Publication Date Title
CN103869162B (en) Dynamic signal phasor measurement method based on time domain quasi-synchronization
CN103245832B (en) Based on harmonic wave time-frequency characteristic method for parameter estimation and the analyser of quick S-transformation
Yang et al. A precise calculation of power system frequency
CN102435844B (en) Sinusoidal signal phasor calculating method being independent of frequency
CN103454497B (en) Based on the method for measuring phase difference improving windowed DFT
CN107247182B (en) Inter-harmonic component reduction method based on measured phasor data
CN104049144A (en) Synchronous phasor measurement implementing method with filtered-out attenuation direct current components
CN104635094A (en) Method for improving PMU (power management unit) synchronous phasor measurement precision
CN103257271A (en) Device and method for detecting micro grid harmonic wave and inter-harmonics based on STM32F107VCT6
CN103116064A (en) Method and device for detecting voltage fluctuation and flicker based on energy operator and spectrum correction
CN203287435U (en) A micro electrical network harmonic wave and inter-harmonic wave test apparatus based on an STM32F107VCT6
CN101915874A (en) Harmonic wave detection method based on Fourier transformation
CN103904693B (en) Based on the synchronized method that frequency self adaptation Virtual shipyard is estimated
CN104502698A (en) Method and system for measuring frequency of electric power signal
CN103543331B (en) A kind of method calculating electric signal harmonic wave and m-Acetyl chlorophosphonazo
CN105487034A (en) 0.05-level electronic transformer verification method and system
CN103983849B (en) A kind of Electric Power Harmonic Analysis method of real-time high-precision
CN109507480A (en) A kind of harmonic detection method and device of neighbouring fundamental wave/harmonic wave
CN102313857A (en) Method and device for analyzing fault recording data of power system
CN105334381A (en) Method and device for measuring AC active power
KR100839436B1 (en) The method of power frequency estimation using the difference between the gain and cosine and sine filter
Kaiser et al. Estimation of power systems amplitudes, frequencies, and phase characteristics using energy operators
Petrovic Frequency and parameter estimation of multi-sinusoidal signal
CN105467209B (en) A kind of new metal oxide arrester leakage current analysis method
CN202119835U (en) Unstable harmonic and interharmonic measuring instrument

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant