CN108508268A - A kind of novel digital type flickermeter decomposed based on time-frequency domain - Google Patents
A kind of novel digital type flickermeter decomposed based on time-frequency domain Download PDFInfo
- Publication number
- CN108508268A CN108508268A CN201810282216.XA CN201810282216A CN108508268A CN 108508268 A CN108508268 A CN 108508268A CN 201810282216 A CN201810282216 A CN 201810282216A CN 108508268 A CN108508268 A CN 108508268A
- Authority
- CN
- China
- Prior art keywords
- module
- frequency domain
- time
- flickermeter
- square
- 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.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/16—Spectrum analysis; Fourier analysis
- G01R23/165—Spectrum analysis; Fourier analysis using filters
- G01R23/167—Spectrum analysis; Fourier analysis using filters with digital filters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Wind Motors (AREA)
Abstract
A kind of novel digital type flickermeter decomposed based on time-frequency domain of the present invention, belongs to wind-power electricity generation detection technique field；The technical problem to be solved is that provide the digital flickermeter for meeting national standard 12326 and requiring and carrying out assistant analysis according to the time-frequency domain information of each voltage fluctuation；Technical solution is：Including signal input module, square demod-ulation module, bandpass filter module, resolution modalities resolving cell, visual sense degree weighted units, time-frequency domain assistant analysis unit, summation unit, square and single order lowpass digital filter, statistical estimation module and output end, signal input module, square demod-ulation module, bandpass filter module, resolution modalities resolving cell is sequentially connected, resolution modalities resolving cell is connected with visual sense degree weighted units and time-frequency domain assistant analysis unit respectively, visual sense degree weighted units, summation unit, square and single order lowpass digital filter, statistical estimation module is sequentially connected with output end；It the composite can be widely applied to wind-powered electricity generation detection field.
Description
Technical field
A kind of novel digital type flickermeter decomposed based on time-frequency domain of the present invention, belongs to wind-power electricity generation detection technique field.
Background technology
The flickering limiting factor one of grid-connected as wind turbine needs accurate evaluation, can be according to national standard《GB
12326-2000 power quality voltage fluctuation and flickers》（Call national standard 12326 in the following text）The method of recommendation is detected.But at this
In method, removes other than statistical estimation link, filter is all designed in actual analog circuit using board design
Overvoltage and overcurrent protection are more complicated, it is therefore desirable to design a kind of digital flickermeter as substitute to meet national standard
12326。。
The digital flickermeter in various full-time domains, full frequency-domain and mixing time-frequency domain is suggested, but is all unable to get wind-powered electricity generation
The time-frequency domain information of each voltage fluctuation in field.Time-frequency domain information is determined for the start/stop time of voltage fluctuation, voltage fluctuation wink
When amplitude variation etc. assistant analysis, can be wind power plant voltage fluctuation analysis and improvement more helps are provided.
WAVELET PACKET DECOMPOSITION and empirical mode decomposition can obtain the time-frequency domain information of each decomposed signal.But due to wind power plant
Voltage fluctuation be one group of narrowband tight frequency low frequency signal, higher Decomposition order is needed using WAVELET PACKET DECOMPOSITION, leads to weight
Larger error is generated because of data deficiencies when each decomposed component of structure；And empirical mode decomposition is not suitable for narrowband tight frequency letter
Number decomposition, and the frequency of each decomposed component can not be directly obtained, also need extra computation.
Invention content
A kind of novel digital type flickermeter decomposed based on time-frequency domain of the present invention, overcomes existing digital flickermeter because lacking
The time-frequency domain information of weary each voltage fluctuation and related assistant analysis can not be carried out, and using traditional time-frequency domain decomposition method assessment
The larger deficiency of flickering error, 12326 required precision of national standard can not only be met by providing, moreover it is possible to according to the time-frequency of each voltage fluctuation
Domain information carries out the digital flickermeter of assistant analysis.
In order to solve the above-mentioned technical problem, the technical solution adopted by the present invention is：It is a kind of based on time-frequency domain decompose it is novel
Digital flickermeter, including signal input module, square demod-ulation module, bandpass filter module, resolution modalities resolving cell, regard
Sensitivity weighted units, time-frequency domain assistant analysis unit, summation unit, square and single order lowpass digital filter, statistical estimation mould
Block and output end, signal input module, square demod-ulation module, bandpass filter module, resolution modalities resolving cell are sequentially connected,
Resolution modalities resolving cell is connected with visual sense degree weighted units and time-frequency domain assistant analysis unit respectively, visual sense degree weighted units,
Summation unit, square and single order lowpass digital filter, statistical estimation module be sequentially connected with output end.
Further, the signal input module includes network voltage input unit, AD conversion unit and standardization processing
Unit, network voltage input unit, AD conversion unit are sequentially connected with standardization processing unit, standardization processing unit and institute
Square demod-ulation module is stated to be connected.
Further, the bandpass filter module includes single order high-pass digital filter and six rank lowpass digital filters,
Single order high-pass digital filter is connected with six rank lowpass digital filters, the square demod-ulation module and single order high-pass digital
Device is connected.
Further, the bound cutoff frequency of the bandpass filter module is respectively 35Hz and 0.05Hz.
Compared with prior art, the invention has the advantages that：Resolution modalities decomposition method is used for wind by the present invention
The flickering of electric field is assessed, and obtained digital flickermeter can not only obtain the flickering assessment for meeting 12326 required precision of national standard
Value, moreover it is possible to obtain the time-frequency domain information of each voltage fluctuation for assistant analysis.
Description of the drawings
Following further describes the present invention with reference to the drawings.
Fig. 1 is the structure diagram of the present invention.
Fig. 2 is the decomposed component figure obtained using WAVELET PACKET DECOMPOSITION.
Fig. 3 is the decomposed component figure obtained using empirical mode decomposition.
Fig. 4 is the decomposed component figure that the resolution modalities resolving cell of the present invention obtains.
Fig. 5 is the relative error figure between obtained short time flicker of the invention and the flickermeter of the recommendation of national standard 12326.
In figure, 1- signal input modules, 2- square demod-ulation modules, 3- bandpass filter modules, 4- resolution modalities decompose single
Member, 5- visual sense degree weighted units, 6- time-frequency domain assistant analysis units, 7- summation units, 8- squares and single order low-pass digital filter
Device, 9- statistical estimation modules, 10- output ends, 11- network voltage input units, 12- AD conversion units, the processing of 13- standardizations
Unit, 31- single order high-pass digital filters, six rank lowpass digital filters of 32-.
Specific implementation mode
As shown in Figure 1, it is a kind of based on time-frequency domain decompose novel digital type flickermeter, including signal input module 1, square
Demodulation module 2, bandpass filter module 3, resolution modalities resolving cell 4, visual sense degree weighted units 5, time-frequency domain assistant analysis list
Member 6, summation unit 7, square and single order lowpass digital filter 8, statistical estimation module 9 and output end 10, signal input module
1, square demod-ulation module 2, bandpass filter module 3, resolution modalities resolving cell 4 are sequentially connected, and resolution modalities resolving cell 4 divides
Be not connected with visual sense degree weighted units 5 and time-frequency domain assistant analysis unit 6, visual sense degree weighted units 5, summation unit 7, square and
Single order lowpass digital filter 8, statistical estimation module 9 are sequentially connected with output end 10.
Signal input module 1 includes network voltage input unit 11, AD conversion unit 12 and standardization processing unit 13,
Network voltage input unit 11, AD conversion unit 12 are sequentially connected with standardization processing unit 13, standardization processing unit 13
It is connected with square demod-ulation module 2.
Bandpass filter module 3 includes single order high-pass digital filter 31 and six rank lowpass digital filters 32, and single order is high
Logical digital filter 31 is connected with six rank lowpass digital filters 32, square demod-ulation module 2 and single order high-pass digital filter 32
It is connected.The bound cutoff frequency of bandpass filter module is respectively 35Hz and 0.05Hz.
Working process and principle of the invention are further illustrated：The network voltage input unit 1 of the present invention connects wind-powered electricity generation
Field points of common connection carries out analog-to-digital conversion using AD conversion unit 12 to collected continuous wind farm voltage, obtains
To discrete network voltage.Using standardization processing unit 13 by discrete network voltage standardization, the power grid of standardization is obtained
Voltage.
The network voltage of standardization is after the demodulation of square demod-ulation module 2, then passes through single order high-pass digital filter 31 successively
With six rank lowpass digital filters 32, the wind power plant voltage fluctuation that frequency is 0.05 ~ 35Hz is obtained.
The selection principle of cutoff frequency：Wind power plant voltage fluctuation focuses primarily upon 0.25 ~ 1.25Hz, to ensure real-time,
The calculation amount that resolution modalities decompose is reduced, therefore is selected at equal intervals by 0.1Hz in 0.05 ~ 2Hz, is selected at equal intervals by 5Hz in 2 ~ 35Hz
It selects.
In summation unit 7, each component of visual sense degree weighted units 5, the voltage wave after being weighted are added in frequency domain
Dynamic time-domain signal.
Square and single order lowpass digital filter 8 play smooth effect, simulate the store-memory effect of human brain, export
It is instantaneous vermicularizing alloy.
Statistical estimation module 9 to square and single order lowpass digital filter 8 export instantaneous vermicularizing alloy carry out probability
Statistics calculates and record, obtains short time flicker value and long-time flickering value, and exported by output end 10.
Assuming that wind power plant only includes single-frequency voltage fluctuation, amplitude 0.01, phase angle 0, frequency is respectively 0.27 ~
1.27Hz is spaced 0.1Hz, the sudden strain of a muscle that the short time flicker that digital flickermeter proposed by the present invention obtains is recommended with national standard 12326
The relative error become between instrument is as shown in Figure 5.
It can be seen that digital flickermeter proposed by the present invention can not only obtain comparing WAVELET PACKET DECOMPOSITION and empirical modal
Decompose the time-frequency domain information of more accurately each voltage fluctuation, moreover it is possible to obtain existing with the flickermeter relative error that national standard 12326 is recommended
Short time flicker value within 1%.
Although being particularly shown and describing the present invention, those skilled in the art with reference to its exemplary embodiment
It should be understood that in the case where not departing from the spirit and scope of the present invention defined by claim, form can be carried out to it
With the various changes in details.
Claims (5)
1. a kind of novel digital type flickermeter decomposed based on time-frequency domain, it is characterised in that：Including signal input module（1）, it is flat
Square demodulation module（2）, bandpass filter module（3）, resolution modalities resolving cell（4）, visual sense degree weighted units（5）, time-frequency domain
Assistant analysis unit（6）, summation unit（7）, square and single order lowpass digital filter（8）, statistical estimation module（9）And output
End（10）, signal input module（1）, square demod-ulation module（2）, bandpass filter module（3）, resolution modalities resolving cell（4）
Sequentially it is connected, resolution modalities resolving cell（4）Respectively with visual sense degree weighted units（5）With time-frequency domain assistant analysis unit（6）Phase
Even, visual sense degree weighted units（5）, summation unit（7）, square and single order lowpass digital filter（8）, statistical estimation module（9）
And output end（10）Sequentially it is connected.
2. a kind of novel digital type flickermeter decomposed based on time-frequency domain according to claim 1, it is characterised in that：It is described
Signal input module（1）Including network voltage input unit（11）, AD conversion unit（12）With standardization processing unit（13）,
Network voltage input unit（11）, AD conversion unit（12）With standardization processing unit（13）Sequentially it is connected, standardization processing
Unit（13）With the square demod-ulation module（2）It is connected.
3. a kind of novel digital type flickermeter decomposed based on time-frequency domain according to claim 2, it is characterised in that：It is described
Bandpass filter module（3）Including single order high-pass digital filter（31）With six rank lowpass digital filters（32）, single order high pass
Digital filter（31）With six rank lowpass digital filters（32）It is connected, the square demod-ulation module（2）With single order high pass digital
Filter（32）It is connected.
4. a kind of novel digital type flickermeter decomposed based on time-frequency domain according to claim 1, it is characterised in that：It is described
Bandpass filter module（3）Bound cutoff frequency be respectively 35Hz and 0.05Hz.
5. a kind of novel digital type flickermeter decomposed based on time-frequency domain according to claim 1, it is characterised in that：It is described
Resolution modalities resolving cell（4）Interior to be equipped with resolution modalities decomposing program, steps are as follows：Assuming that by bandpass filter module（3）It is defeated
The wind power plant voltage fluctuation of 0.05 ~ 35Hz of the demodulation gone out isIf cutoff frequency is respectively, then
Frequency space is broken down into n+1 interval；If every
One interval only includes a tight frequency voltage fluctuation, then each tight frequency voltage fluctuationAnalytical expression can
Pass through（Formula 1）With（Formula 2）It calculates,
(formula 1),
(formula 2),
Wherein,,For Hilbert transform, the integral of cutoff frequency；,。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810282216.XA CN108508268A (en) | 2018-04-02 | 2018-04-02 | A kind of novel digital type flickermeter decomposed based on time-frequency domain |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810282216.XA CN108508268A (en) | 2018-04-02 | 2018-04-02 | A kind of novel digital type flickermeter decomposed based on time-frequency domain |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108508268A true CN108508268A (en) | 2018-09-07 |
Family
ID=63379845
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810282216.XA Pending CN108508268A (en) | 2018-04-02 | 2018-04-02 | A kind of novel digital type flickermeter decomposed based on time-frequency domain |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108508268A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111723684A (en) * | 2020-05-29 | 2020-09-29 | 华南理工大学 | Method for identifying transient overvoltage type in offshore wind farm |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103034757A (en) * | 2012-12-02 | 2013-04-10 | 中国科学院电工研究所 | Wind farm time-frequency domain modeling method based on empirical mode decomposition (EMD) |
| CN104360198A (en) * | 2014-11-19 | 2015-02-18 | 云南电网公司电力科学研究院 | High-performance power quality analyzer |
| CN104677580A (en) * | 2015-01-30 | 2015-06-03 | 燕山大学 | Rotary mechanical fault diagnosis method based on analytical modal decomposition |
| CN105652084A (en) * | 2015-12-31 | 2016-06-08 | 山西大学 | EIAMD-based wind power plant 3p CFVFs detection method |
| CN205539144U (en) * | 2016-04-08 | 2016-08-31 | 韶关市擎能设计有限公司 | Voltage flicker measuring apparatu |
| CN107748734A (en) * | 2017-10-31 | 2018-03-02 | 电子科技大学 | One kind parsing empirical mode decomposition method |
-
2018
- 2018-04-02 CN CN201810282216.XA patent/CN108508268A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103034757A (en) * | 2012-12-02 | 2013-04-10 | 中国科学院电工研究所 | Wind farm time-frequency domain modeling method based on empirical mode decomposition (EMD) |
| CN104360198A (en) * | 2014-11-19 | 2015-02-18 | 云南电网公司电力科学研究院 | High-performance power quality analyzer |
| CN104677580A (en) * | 2015-01-30 | 2015-06-03 | 燕山大学 | Rotary mechanical fault diagnosis method based on analytical modal decomposition |
| CN105652084A (en) * | 2015-12-31 | 2016-06-08 | 山西大学 | EIAMD-based wind power plant 3p CFVFs detection method |
| CN205539144U (en) * | 2016-04-08 | 2016-08-31 | 韶关市擎能设计有限公司 | Voltage flicker measuring apparatu |
| CN107748734A (en) * | 2017-10-31 | 2018-03-02 | 电子科技大学 | One kind parsing empirical mode decomposition method |
Non-Patent Citations (5)
| Title |
|---|
| 叶韵: "电压闪变测量的数字化实现", 《电力电子》 * |
| 李霏霏 等: "一种由间谐波估计电压闪变参数的简便方法", 《电力系统保护与控制》 * |
| 王建勋 等: "高频间谐波引起闪变的时频混合测量方法", 《电力系统自动化》 * |
| 王彭 等: "IEC闪变检测方法的数字化实现", 《中国电力教育》 * |
| 邓志: "一种高精度闪变分析仪", 《智能电网》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111723684A (en) * | 2020-05-29 | 2020-09-29 | 华南理工大学 | Method for identifying transient overvoltage type in offshore wind farm |
| CN111723684B (en) * | 2020-05-29 | 2023-07-21 | 华南理工大学 | Identification method for transient overvoltage type in offshore wind farm |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105116245B (en) | A kind of electric energy quality on-line monitoring device based on Ethernet | |
| CN103926456B (en) | Flicker value calculation method based on improved FFT and inverter | |
| CN109061302A (en) | A kind of wind power generator incorporated in power network group harmonic measure system converted based on EEMD and Hilbert | |
| CN107886171B (en) | PMU data-based breaker state online diagnosis method and system | |
| CN116703183B (en) | Novel power distribution network system power load assessment method | |
| CN1200177A (en) | Method of locating a single-phase ground fault in a power distribution network | |
| CN104714075B (en) | A kind of electric network voltage flicker envelope parameters extracting method | |
| CN108549999B (en) | Offshore wind power quality data analysis method and system based on wind speed interval | |
| CN107219391A (en) | Quality of voltage Monitoring Indexes device | |
| Kim | Fault detection algorithm of the photovoltaic system using wavelet transform | |
| CN102981082B (en) | Based on Wind turbines flickering simulated testing system and the method for virtual grid simulation | |
| CN108169540A (en) | A kind of measuring method of wind power generating set voltage flicker | |
| CN106647706B (en) | Wind turbines tower off-load verification method and system | |
| CN108508268A (en) | A kind of novel digital type flickermeter decomposed based on time-frequency domain | |
| CN203117395U (en) | Unit plant primary frequency modulation performance dynamic monitoring system | |
| Dołęgowski et al. | A novel algorithm for fast DC electric arc detection | |
| CN115808600B (en) | DC arc detection method based on mathematical morphology and pattern recognition | |
| CN113484654B (en) | Power quality monitoring and identifying method based on double-tree complex wavelet transformation | |
| CN109782064B (en) | Wind power plant output impedance frequency characteristic test analysis method | |
| CN114623925A (en) | Intelligent detection system and method for field noise of power grid transformation project | |
| CN114924157A (en) | Parallel reactor state monitoring method and system based on 5G transmission | |
| CN104360198A (en) | High-performance power quality analyzer | |
| Li et al. | Voltage Fluctuation and Flicker Monitoring System Using LabVIEW and Wavelet Transform. | |
| Wu et al. | A time frequency domain digital implementation of flickermeter using analytical mode decomposition | |
| Zhang et al. | Fault diagnosis of gear based on singular value decomposition and RBF neural network |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20180907 |