CN103592513A - Power signal harmonic analysis method and device - Google Patents
Power signal harmonic analysis method and device Download PDFInfo
- Publication number
- CN103592513A CN103592513A CN201310580763.3A CN201310580763A CN103592513A CN 103592513 A CN103592513 A CN 103592513A CN 201310580763 A CN201310580763 A CN 201310580763A CN 103592513 A CN103592513 A CN 103592513A
- Authority
- CN
- China
- Prior art keywords
- frequency
- count
- sampling
- harmonic
- power frequency
- 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.)
- Granted
Links
Landscapes
- Measuring Frequencies, Analyzing Spectra (AREA)
Abstract
The invention discloses a power signal harmonic analysis method which comprises the steps of (1) selecting a phase voltage or a phase current, utilizing a high-frequency counting clock for counting power frequency signals, obtaining a total counting value through a plurality of periods, dividing the total counting value by the number of the periods to obtain the average counting value of the power frequency signals, (2) determining the counting step length of the sampling periods as time intervals of the sampling periods, (3) obtaining an initial point of the power frequency signals through circuit detection, (4) conducting the Fourier conversion in the DFT mode, and only calculating the amplitude and the phase angle of an interested harmonic component.
Description
Technical field
The present invention relates to a kind of Power signal processing method, particularly a kind of electric power signal harmonic analysis method and device.
Background technology
In prior art, electric power signal is carried out to frequency analysis, generally have two kinds of modes: 1, PLL synchronous sampling circuit analysis; 2, windowed interpolation analysis.
Above-mentioned two kinds of modes, are all by gathering synchronizing signal, or obtain a burst by windowed interpolation, then carry out FFT conversion, obtain each harmonic component.
Phaselocked loop requires synchronous to electric power signal, wherein may relate to high frequency multiplication, and it has increased the degree of difficulty of circuit design.
FFT transformation calculations goes out all harmonic value, but in fact only need measure wherein fractional harmonic, has virtually increased calculated amount.
Therefore, provide a kind of and can accurately calculate power frequency component frequency and the little electric power signal harmonic analysis method of calculated amount becomes urgent problem in the industry.
Summary of the invention
The object of this invention is to provide a kind of electric power signal harmonic analysis method and device, it can accurately calculate power frequency component frequency and can effectively reduce calculated amount.
According to the present invention, a kind of electric power signal harmonic analysis method is provided, comprising: (1) selects a phase voltage, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, divided by amount of cycles, obtain the average counter value of power frequency component again; (2) determine the time interval of the counting step-length in sampling period as the sampling period; (3) by electric circuit inspection, obtain the starting point of power frequency component; And (4) take DFT mode to carry out Fourier transformation, only calculate amplitude and the phase angle of interested harmonic component.
Preferably, the invention provides a kind of electric power signal harmonic analysis method, comprise: (1) selects a phase voltage, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, then divided by amount of cycles, obtain the average counter value of power frequency component; (2) determine the time interval of the counting step-length in sampling period as the sampling period; (3) zero crossing of sinusoidal wave ascent stage that obtains power frequency component by electric circuit inspection is as the starting point of power frequency component; And (4) take DFT mode to carry out Fourier transformation, only calculate amplitude and the phase angle of interested harmonic component.
More preferably, the invention provides a kind of electric power signal harmonic analysis method, comprise: (1) selects a phase voltage, utilize high-frequency counting clock, zero crossing at power frequency component starts to count, and through several, spends null cycle, obtains count value altogether, divided by amount of cycles, obtain the average counter value of power frequency component again; (2) determine the time interval of the counting step-length in sampling period as the sampling period; (3) zero crossing of sinusoidal wave ascent stage that obtains power frequency component by electric circuit inspection is as the starting point of power frequency component; And (4) take DFT mode to carry out Fourier transformation, only calculate amplitude and the phase angle of interested harmonic component.
Wherein, discrete Fourier transformation (Discrete Fourier Transform, is abbreviated as DFT), is that Fourier transform is all discrete form on time domain and frequency domain, the time-domain sampling of signal is transformed to the frequency domain sample of its DTFT.In form, the sequence at conversion two ends (on time domain and frequency domain) is time-limited, and in fact these two groups of sequences all should be considered to the main value sequence of Discrete Periodic Signals.Even time-limited discrete signal is made to DFT, also should be regarded as the conversion of its periodic extension.Conventionally adopt in actual applications Fast Fourier Transform (FFT) to calculate DFT.
Selectively, from the starting point of ADC output, start to count, counting step is 2N starting point, and count value is S, and count frequency is fc, and the signal frequency of being tested is fcN/S.
Preferably, from the zero crossing of ADC output, start to count, counting step is 2N zero crossing, and count value is S, and count frequency is fc, and the signal frequency of being tested is fcN/S.
Wherein, ADC, the abbreviation of Analog-to-Digital Converter, refers to A/D converter or analog/digital converter.Refer to the device that the simulating signal of continuous variable is converted to discrete digital signal.
Preferably, at the zero crossing of power frequency component, start to count, through several, spend null cycle, obtain count value altogether.
Selectively, doubly, i.e. each cycle sampling M point, take fc as count frequency to the M that setting sample frequency is power frequency, determines that sampling step length is S/N/M.
Selectively, the scope of M value is 100～150.
Selectively, every cycle sampling M point, P the cycle of sampling altogether, obtains common M*P point sequence of real numbers.
Selectively, the scope of P value is 5～15.
Preferably, M value is that 128, P value is 8, to resulting 1024 point sequences, takes DFT mode to carry out Fourier transformation, and formula is as follows:
Wherein, spectral resolution f0/8, the 8th, 16 of frequency spectrum ..., 8m component is respectively first-harmonic, second harmonic ..., m subharmonic;
Corresponding amplitude is
Phase angle is
m=8,16 ..., 8i..., (i=1,2,3...).
Wherein, the amplitude calculating and phase angle are the relative values based on first-harmonic.
The present invention also provides a kind of electric power signal frequency analysis device, comprise: power frequency component average counter value acquisition device, power frequency component average counter value acquisition device is selected a phase voltage, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, then divided by amount of cycles, obtain the average counter value of power frequency component; The time interval in sampling period determining device, the time interval in sampling period determining device is usingd the counting step-length in sampling period as time interval in sampling period; Power frequency component starting point pick-up unit, power frequency component starting point pick-up unit obtains the starting point of power frequency component by electric circuit inspection; And computational analysis device, computational analysis device takes DFT mode to carry out Fourier transformation, only calculates amplitude and the phase angle of interested harmonic component.
Preferably, a kind of electric power signal frequency analysis device is provided, comprise: power frequency component average counter value acquisition device, power frequency component average counter value acquisition device is selected a phase voltage, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, divided by amount of cycles, obtain the average counter value of power frequency component again; The time interval in sampling period determining device, the time interval in sampling period determining device is usingd the counting step-length in sampling period as time interval in sampling period; Power frequency component starting point pick-up unit, power frequency component starting point pick-up unit obtains the zero crossing of sinusoidal wave ascent stage of power frequency component as the starting point of power frequency component by electric circuit inspection; And computational analysis device, computational analysis device takes DFT mode to carry out Fourier transformation, only calculates amplitude and the phase angle of interested harmonic component.
Wherein, power frequency component average counter value acquisition device starts to count from the zero crossing of ADC output, and counting step is 2N zero crossing, and count value is S, and count frequency is fc, and the signal frequency of being tested is fcN/S.
Wherein, the time interval in sampling period determining device is set M times that sample frequency is power frequency, i.e. each cycle sampling M point, take fc as count frequency, determines that sampling step length is S/N/M.
Wherein, computational analysis device is set every cycle sampling M point, and P the cycle of sampling altogether, obtains common M*P point sequence of real numbers.
The invention has the beneficial effects as follows: (1) adopts unique sample-synchronous mode; (2) adopt DFT mode, only interested harmonic wave is calculated.Therefore,, when guaranteeing accurately to calculate power frequency component frequency, effectively reduce calculated amount.
Embodiment
The present invention discloses a kind of electric power signal harmonic analysis method and device, is characterized in adopting unique sample-synchronous mode, and adopts DFT mode only interested harmonic wave to be calculated.
The sampled point that frequency analysis is used, need to be with electric power signal with homophase frequently, synchronous sampling signal namely, and first the present invention carries out frequency measurement, then in cycle starting point, starts sampling, can meet above-mentioned requirements.
Measure the cycle of power frequency component, utilize high-frequency counting clock, zero crossing at power frequency component starts to count, through a plurality of, spend null cycle, in for example 100,1000 cycles, obtain count value altogether, again divided by amount of cycles, obtain the average counter value of a power frequency component, and counting clock is more accurately, so just can calculate the frequency of power frequency component more accurately.
After determining work frequency, can obtain the counting step-length in sampling period, this time interval that is the sampling period.
In order to reach sampling and power frequency component with homophase frequently, need to determine the starting point of power frequency component, the zero crossing of sinusoidal wave ascent stage of take is starting point, this point can arrive by electric circuit inspection.
Like this, the in the situation that of all definite in starting point and time cycle, can collect the burst needing.
It is valuable that frequency analysis only has fractional harmonic, and Fourier transformation analysis may produce and permitted multiple-harmonic result, 1024 FFT of for example take are example, this FFT conversion can analyze 1024 harmonic value simultaneously, but only wherein tens be useful, for example 51, remaining harmonic value is exactly unnecessary so, and calculated amount is very large.
Therefore, we wish to calculate interested part by DFT, with this, reduce calculated amount.
A specific embodiments of this algorithm below.
1. mains frequency is measured
Select a phase voltage to measure, from the zero crossing of ADC output, start to count, counting step is 2N zero crossing, and count value is S, and count frequency is fc, and the mains frequency of being tested is fcN/S.
2. sample frequency determines
Suppose that sample frequency is 128 times of power frequency, each cycle 128 points of sampling, take fc as count frequency, determine sampling or the step-length of the clock of extracted data is S/N/128.
3. sampling clock phase determines
For accomplishing that sampled data and civil power are with frequency homophase, need to determine that sampling output or the initial position of extracted data are positioned at the zero crossing of civil power.
4. sampling length determines
Every cycle 128 points of sampling, 8 cycles of sampling altogether, obtain totally 1024 sequence of real numbers.
5. Harmonics Calculation
To resulting 1024 point sequences, take DFT mode to carry out Fourier transformation, only calculate amplitude and the phase angle of interested harmonic component.
The spectral resolution f of the Fourier transformation of this mode
0/ 8, thus frequency spectrum the 8th, 16 ..., 8m component is respectively first-harmonic, second harmonic ..., m subharmonic.
Corresponding amplitude is
Phase angle is
m=8,16 ..., 8i..., (i=1,2,3...).
The present invention also provides a kind of electric power signal frequency analysis device, it comprises: power frequency component average counter value acquisition device, power frequency component average counter value acquisition device is selected a phase voltage, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, again divided by amount of cycles, obtain the average counter value of power frequency component, power frequency component average counter value acquisition device starts to count from the zero crossing of ADC output, counting step is 2N zero crossing, count value is S, count frequency is fc, the signal frequency of being tested is fcN/S, the time interval in sampling period determining device, the time interval in sampling period determining device is usingd the counting step-length in sampling period as time interval in sampling period, the time interval in sampling period determining device is set M times that sample frequency is power frequency, it is each cycle sampling M point, take fc as count frequency, determine that sampling step length is S/N/M, power frequency component starting point pick-up unit, power frequency component starting point pick-up unit obtains the zero crossing of sinusoidal wave ascent stage of power frequency component as the starting point of power frequency component by electric circuit inspection, and computational analysis device, computational analysis device takes DFT mode to carry out Fourier transformation, only calculates amplitude and the phase angle of interested harmonic component, and computational analysis device is set every cycle sampling M point, and P the cycle of sampling altogether, obtains common M*P point sequence of real numbers.
Although described the preferred embodiment of the present invention in detail at this, but should be understood that the present invention is not limited to the concrete structure of describing in detail and illustrating here, in the situation that not departing from the spirit and scope of the invention, can be realized by those skilled in the art other modification and variant.
Claims (10)
1. an electric power signal harmonic analysis method, comprising:
(1) select a phase voltage or electric current, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, then divided by amount of cycles, obtain the average counter value of power frequency component;
(2) determine the time interval of the counting step-length in sampling period as the sampling period;
(3) take DFT mode to carry out Fourier transformation, only calculate the amplitude of interested harmonic component;
(4) by electric circuit inspection, obtain the starting point of power frequency component; And
(5) the described starting point obtaining based on step (4), takes DFT mode to carry out Fourier transformation, only calculates the phase angle of interested harmonic component.
2. electric power signal harmonic analysis method as claimed in claim 1, is characterized in that, from the starting point of ADC output, starts to count, and counting step is 2N starting point, and count value is S, and count frequency is fc, and the signal frequency of being tested is fcN/S.
3. electric power signal harmonic analysis method as claimed in claim 2, is characterized in that, doubly, i.e. each cycle sampling M point, take fc as count frequency to the M that setting sample frequency is power frequency, determines that sampling step length is S/N/M.
4. electric power signal harmonic analysis method as claimed in claim 3, is characterized in that, every cycle sampling M point, and P the cycle of sampling altogether, obtains common M*P point sequence of real numbers.
5. electric power signal harmonic analysis method as claimed in claim 4, is characterized in that, M value is that 128, P value is 8, to resulting 1024 point sequences, takes DFT mode to carry out Fourier transformation, and formula is as follows:
Wherein, spectral resolution f0/8, the 8th, 16 of frequency spectrum ..., 8m component is respectively first-harmonic, second harmonic ..., m subharmonic;
Corresponding amplitude is
Phase angle is
m=8,16 ..., 8i..., (i=1,2,3...).
6. electric power signal harmonic analysis method as claimed in claim 5, is characterized in that, the amplitude calculating and phase angle are the relative values based on first-harmonic.
7. an electric power signal frequency analysis device, comprising:
Power frequency component average counter value acquisition device, described power frequency component average counter value acquisition device is selected a phase voltage, utilize high-frequency counting clock to count power frequency component, through several cycles, obtain count value altogether, divided by amount of cycles, obtain the average counter value of power frequency component again;
The time interval in sampling period determining device, the described time interval in sampling period determining device is usingd the counting step-length in sampling period as time interval in sampling period;
Power frequency component starting point pick-up unit, described power frequency component starting point pick-up unit obtains the starting point of power frequency component by electric circuit inspection; And
Computational analysis device, described computational analysis device takes DFT mode to carry out Fourier transformation, only calculates the amplitude of interested harmonic component, and the starting point of the power frequency component based on obtained is only calculated the phase angle of interested harmonic component.
8. electric power signal frequency analysis device as claimed in claim 7, it is characterized in that, described power frequency component average counter value acquisition device starts to count from the starting point of ADC output, counting step is 2N starting point, count value is S, count frequency is fc, and the signal frequency of being tested is fcN/S.
9. electric power signal frequency analysis device as claimed in claim 8, is characterized in that, the described time interval in sampling period determining device is set M times that sample frequency is power frequency, i.e. each cycle sampling M point, take fc as count frequency, determines that sampling step length is S/N/M.
10. electric power signal frequency analysis device as claimed in claim 9, is characterized in that, described computational analysis device is set every cycle sampling M point, and P the cycle of sampling altogether, obtains common M*P point sequence of real numbers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310580763.3A CN103592513B (en) | 2013-11-20 | 2013-11-20 | Electric power signal harmonic analysis method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310580763.3A CN103592513B (en) | 2013-11-20 | 2013-11-20 | Electric power signal harmonic analysis method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103592513A true CN103592513A (en) | 2014-02-19 |
| CN103592513B CN103592513B (en) | 2016-06-08 |
Family
ID=50082730
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310580763.3A Expired - Fee Related CN103592513B (en) | 2013-11-20 | 2013-11-20 | Electric power signal harmonic analysis method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103592513B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108362940A (en) * | 2018-03-14 | 2018-08-03 | 贵州电网有限责任公司 | A kind of dynamic harmonic frequency extraction method of half cycles distorted signal |
| CN113820539A (en) * | 2021-08-19 | 2021-12-21 | 南京国电南自电网自动化有限公司 | Harmonic and inter-harmonic angle calibration method and system based on fundamental angle calibration |
| CN114705913A (en) * | 2022-04-12 | 2022-07-05 | 上海赢双电机有限公司 | Harmonic analysis method of rotary transformer |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009100614A (en) * | 2007-10-19 | 2009-05-07 | Chugoku Electric Power Co Inc:The | Sampling pulse generating circuit |
| CN102288819A (en) * | 2011-08-18 | 2011-12-21 | 东北大学 | FPGA (field programmable gate array)-based power harmonic analyzer |
| CN102393488A (en) * | 2011-08-24 | 2012-03-28 | 江苏技术师范学院 | Harmonic analysis method |
| CN102508026A (en) * | 2011-10-21 | 2012-06-20 | 江苏技术师范学院 | Harmonic wave analysis method for electric energy quality harmonic wave analyzer |
-
2013
- 2013-11-20 CN CN201310580763.3A patent/CN103592513B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009100614A (en) * | 2007-10-19 | 2009-05-07 | Chugoku Electric Power Co Inc:The | Sampling pulse generating circuit |
| CN102288819A (en) * | 2011-08-18 | 2011-12-21 | 东北大学 | FPGA (field programmable gate array)-based power harmonic analyzer |
| CN102393488A (en) * | 2011-08-24 | 2012-03-28 | 江苏技术师范学院 | Harmonic analysis method |
| CN102508026A (en) * | 2011-10-21 | 2012-06-20 | 江苏技术师范学院 | Harmonic wave analysis method for electric energy quality harmonic wave analyzer |
Non-Patent Citations (3)
| Title |
|---|
| 曾博等: "改进FFT非稳态电力谐波分析及应用", 《电工技术学报》 * |
| 梅红伟等: "改善电力系统谐波分析的加窗插值算法和递推傅式算法", 《继电器》 * |
| 王柏林等: "电网谐波分析的频率估计与跟踪", 《电测与仪表》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108362940A (en) * | 2018-03-14 | 2018-08-03 | 贵州电网有限责任公司 | A kind of dynamic harmonic frequency extraction method of half cycles distorted signal |
| CN108362940B (en) * | 2018-03-14 | 2020-07-14 | 贵州电网有限责任公司 | Dynamic harmonic frequency extraction method of half-cycle distortion signal |
| CN113820539A (en) * | 2021-08-19 | 2021-12-21 | 南京国电南自电网自动化有限公司 | Harmonic and inter-harmonic angle calibration method and system based on fundamental angle calibration |
| CN113820539B (en) * | 2021-08-19 | 2024-05-28 | 南京国电南自电网自动化有限公司 | Harmonic wave and inter-harmonic wave angle calibration method and system based on fundamental wave angle calibration |
| CN114705913A (en) * | 2022-04-12 | 2022-07-05 | 上海赢双电机有限公司 | Harmonic analysis method of rotary transformer |
| CN114705913B (en) * | 2022-04-12 | 2024-01-09 | 上海赢双电机科技股份有限公司 | Harmonic analysis method of rotary transformer |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103592513B (en) | 2016-06-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101806832B (en) | Measuring method for frequencies of low-frequency signals | |
| CN103869162B (en) | Dynamic signal phasor measurement method based on time domain quasi-synchronization | |
| CN102435844A (en) | Sinusoidal signal phasor calculating method being independent of frequency | |
| CN103983849B (en) | A kind of Electric Power Harmonic Analysis method of real-time high-precision | |
| CN102879639A (en) | Real-time frequency measuring method in power system | |
| CN203287435U (en) | A micro electrical network harmonic wave and inter-harmonic wave test apparatus based on an STM32F107VCT6 | |
| CN104330623B (en) | Sine wave parameter measuring method and system in electric power system | |
| CN103575984A (en) | Harmonic analysis method based on Kaiser window double-spectral-line interpolation FFT | |
| CN102809687B (en) | Digital measurement method for alternating-current frequency | |
| CN105203837A (en) | Reactive power measurement method | |
| CN103018555A (en) | High-precision electric power parameter software synchronous sampling method | |
| CN105486921A (en) | Kaiser third-order mutual convolution window triple-spectrum-line interpolation harmonic wave and inter-harmonic wave detection method | |
| CN104181391A (en) | Harmonic detection method of digital power meter | |
| CN103592513B (en) | Electric power signal harmonic analysis method and device | |
| CN103969508A (en) | Real-time high-precision power harmonic analysis method and device | |
| CN103543331B (en) | A kind of method calculating electric signal harmonic wave and m-Acetyl chlorophosphonazo | |
| CN109030957B (en) | Dielectric loss measuring method | |
| CN110068729A (en) | A kind of signal phasor calculating method | |
| CN103575979A (en) | Method for digital measuring of alternating current frequency | |
| CN104407197A (en) | Signal phasor measurement method based on trigonometric function iteration | |
| CN105334388A (en) | Method and device for processing signals | |
| CN109521269A (en) | A kind of am signals digitlization frequency measuring method | |
| CN104849551B (en) | Harmonic phase angle analysis method | |
| CN103267896B (en) | Method for measuring initial phase angle of periodic signal | |
| RU2363005C1 (en) | Method of spectral analysis of polyharmonic signals and device to this end |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: 102300, 1, East Road, Shilong Industrial District, Mentougou, Beijing Applicant after: BEIJING FUGEN Electric CO., LTD. Address before: 102300, 1, East Road, Shilong Industrial District, Mentougou, Beijing Applicant before: BEIJING FUGEN INTELLIGENT METER CO., LTD. |
|
| COR | Change of bibliographic data | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20160608 Termination date: 20181120 |