CN107632237A - A kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure - Google Patents
A kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure Download PDFInfo
- Publication number
- CN107632237A CN107632237A CN201710702938.1A CN201710702938A CN107632237A CN 107632237 A CN107632237 A CN 107632237A CN 201710702938 A CN201710702938 A CN 201710702938A CN 107632237 A CN107632237 A CN 107632237A
- Authority
- CN
- China
- Prior art keywords
- correlation
- phase
- wavelet
- failure
- characteristic quantity
- 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
Landscapes
- Locating Faults (AREA)
Abstract
The present invention relates to a kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure.Pass through the data in route survey terminal gather the electric current and voltage of three-phase and zero sequence totally 8 road signals two sampling periods after a failure.To obtaining the characteristic quantity of one group of waveform after the data progress wavelet transformation in two sampling periods.Voltage and current is analyzed using different wavelet algorithms, the characteristic quantity of totally 6 groups of waveforms is obtained, the correlation of every group of characteristic quantity is analyzed, and compared with setting valve.If circuit exceedes setting, quantity result does not meet setting valve, judges that singlephase earth fault occurs for the outlet.Beneficial effects of the present invention are：Judged using a variety of wavelet decomposition algorithms, make use of wavelet algorithm to the hypersensitivity of catastrophe point, avoid the error erroneous judgement that a kind of wavelet algorithm is likely to occur, and reached the purpose of accurate judgement singlephase earth fault outlet by the correlation analysis of characteristic quantity.
Description
Technical field
The present invention relates to electric power system power distribution field, especially a kind of side of low-voltage network single-phase earth fault line selection
Method.
Background technology
China's low and medium voltage distribution network uses small current neutral grounding mode mostly, and singlephase earth fault easily occurs for long-play.
Singlephase earth fault is power distribution network occurrence frequency highest fault type.With modern city development and power system it is continuous
Extension, outlet number increase significantly, and system capacity current greatly increases, and fault current is also more much larger than before after breaking down,
The arc overvoltage of power system can be caused when serious, the insulation protection of power system is threatened, cause the damage of electric power facility, endangered
And the safe operation of whole system.Therefore, after singlephase earth fault occurs for power distribution network, trouble point is found in time and removes failure
Point is necessary.
Traditional patrolling method can expend many manpower and materials, and add power off time, and then influence power system
Power supply reliability.And traditional fault automatic location method is found out specific trouble point and is not easy very much.It is because single-phase in power distribution network
Electric characteristic amount unobvious after earth fault generation, and its characteristic quantity is complicated and diversified.Because failure situation is complicated,
And influenceed by factors such as line construction parameter, transformer nonlinear characteristic, electromagnetic interferences, the frequency spectrum of fault transient zero-sequence current
Characteristic, Energy distribution and attenuation characteristic have very big difference, so power distribution network lacks reliable singlephase earth fault choosing always
Line method, conventional method can not comprehensively be analyzed and cause route selection difficult.
The content of the invention
The invention solves the shortcomings that above-mentioned prior art, there is provided one kind can realize that fast failure positions, based on failure
The fault line selection method for single-phase-to-ground fault of wavelet character amount correlation afterwards.
The present invention solves the technical scheme that its technical problem uses：
Since in the short time that singlephase earth fault occurs, the three-phase of faulty line and the waveform rate of change of zero sequence electric signal
It is greater than the three-phase of non-fault line and the waveform rate of change of zero sequence electric signal, so when singlephase earth fault occurs for system,
The three-phase and zero sequence electric signal waveform rate of change of failure outlet can be different with non-fault line.And small echo change is carried out to signal
The characteristic quantity of each waveform extracted after changing is also different, therefore can carry out failure line selection according to these characteristic quantities.
This fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure, by installing on the line
The measuring terminals of diverse location are accurately captured electric current and the voltage two sampling weeks after totally 8 road signal faults of three-phase and zero sequence
The data of phase.Wavelet transformation analysis is carried out to three-phase and zero sequence electric signal, its HFS and low frequency part totally 8 is calculated
Data, the characteristic quantity as waveform.The characteristic quantity of one group of waveform is obtained after analyzing the waveform in two sampling periods.To electricity
Pressure and electric current are analyzed using different wavelet algorithms, preferably, using db4, db6 and db8 wavelet algorithm, obtain totally 6
The characteristic quantity of group waveform, is analyzed the correlation of every group of characteristic quantity.
The similitude of one group of wave character amount can be described with coefficient correlation, and coefficient correlation can be by grey relational grade side
Method or other mathematical algorithms are asked for.Preferably, the calculation formula of correlation coefficient ρ is as follows:
In formula：i1And i2The wave character amount in respectively 2 sampling periods；
The n amount of being characterized sequences, N are the data length of sequence.
Correlation coefficient ρ reflects one group of wave character amount i1And i (n)2(n) similarity degree.When 2 signals are consistent, ρ takes
Obtain maximum 1；When 2 signals are completely irrelevant, ρ 0.When singlephase earth fault occurs for system, each electricity of non-faulting outlet
The similarity degrees of two sampling period waveforms of signal is high, and coefficient correlation levels off to 1；Two of each electric signal of failure outlet
The similarity degree of sampling period waveform is low, and different wave shape is larger, and coefficient correlation is close to 0.
Correlation coefficient ρ is asked for by coefficient correlation computing module respectively to 6 groups of wave character amounts1、ρ2、ρ3、ρ4、ρ5、ρ6, and
Respectively compared with coefficient correlation setting value.If circuit exceedes setting, quantity result does not meet setting value, judges that this goes out
Singlephase earth fault occurs for line, and specifically setting is as follows for the criterion：
If ρ1<K1, then a=1, otherwise a=0；
If ρ2<K2, then b=1, otherwise b=0；
If ρ3<K3, then c=1, otherwise c=0；
If ρ4<K4, then d=1, otherwise d=0；
If ρ5<K5, then e=1, otherwise e=0；
If ρ6<K6, then f=1, otherwise f=0；
M=a+b+c+d+e+f >=n；
In formula, ρ1、ρ2、ρ3、ρ4、ρ5、ρ6：The coefficient correlation of 6 groups of selected wave character amounts；
K1、K2、K3、K4、K5、K6：The setting value of the coefficient correlation of 6 groups of selected wave character amounts；
A, b, c, d, e, m, n：Decision logic amount.
Preferably, the setting value of the coefficient correlation meets 0.35<K1、K2、K3、K4、K5、K6<0.6。
Preferably, the decision logic value n=4 or 5.
Preferably, this method uses circuits below structure, including three-phase current IA,IB,ICThree inputs and one
Connected zero sequence pass filter input；Three-phase voltage UA,UB,UCThree inputs and one be connected thereto the zero sequence connect
Pass filter input；Electric current and voltage output end are connected with wavelet transform unit respectively, and wavelet transformation analysis is carried out to signal；Through
The sampled signal characteristic quantity of wavelet transformation extraction is connected with coefficient correlation computing unit respectively, to calculate each pair wave character amount
Correlation coefficient ρ1、ρ2、ρ3、ρ4、ρ5、ρ6；6 coefficient correlations are respectively outputted to the negative input end of six comparators, tuning coefficient value
K1、K2、K3、K4、K5、K6It is respectively outputted to the positive input terminal of respective comparator；Six comparator outputs are connected to an adder；
The output of adder is connected to the positive input terminal of comparator, and negative input end is setting valve n, comparator output route selection result and action
Signal.
The invention aims to overcome conventional failure method of discrimination can not analyze matching somebody with somebody under different earthing modes comprehensively
The faulty line and non-fault line during singlephase earth fault occur in power network, proposes a kind of waveform correlation analysis after being based on failure
Fault line selection method for single-phase-to-ground fault.By being sampled to the three-phase of each bar outlet and zero sequence electric signal after failure, Ran Houjin
The wavelet transformation analysis of row m ultiwavelet algorithm and the correlation analysis of characteristic quantity, when signal characteristics value coefficient correlation is more than necessarily
Show that circuit running status is mutated during setting value, i.e., there occurs failure.
The beneficial effects of the invention are as follows：Decomposed and judged using a variety of wavelet decomposition algorithms, both make use of wavelet algorithm to prominent
The hypersensitivity of height, it turn avoid the error erroneous judgement that a kind of wavelet algorithm is likely to occur, and the correlation point for passing through characteristic quantity
Analysis has reached the purpose of accurate judgement singlephase earth fault outlet.The present invention carry can fast positioning failure, there is higher essence
Degree and reliability, and be adapted to realize that there is good social and economic benefit on power distribution automation on-site terminal unit F TU.
Brief description of the drawings
Fig. 1 is the circuit block diagram of the present invention；
Embodiment
The invention will be further described below in conjunction with the accompanying drawings：
Embodiment：A kind of as shown in figure 1, power system low-voltage network system single-phase earth fault route selecting method.FTU is supervised
Sight path and block switch running status are simultaneously controlled to block switch.When short trouble occurs in circuit, FTU was detected
Current phenomena, three-phase and the electric current and electricity of zero sequence are accurately captured by the measuring terminals FTU for installing diverse location on the line
The pressure data of totally 8 road signals second round after a failure and period 4.Record three-phase current and zero-sequence current two adopt
The data in sample cycle, and the data in two sampling periods of three-phase voltage and residual voltage.Three-phase and zero sequence electric signal are entered
Row wavelet transformation analysis, its HFS and low frequency part totally 8 data, the characteristic quantity as waveform is calculated.To two
The waveform in sampling period obtains the characteristic quantity of one group of waveform after being analyzed.Voltage and current is entered using different wavelet algorithms
Row analysis, preferably, using db4, db6 and db8 wavelet algorithm, obtains the characteristic quantity of totally 6 groups of waveforms, to every group of characteristic quantity
Correlation is analyzed.
The similarity degree of each pair waveform is calculated using the circuit structure of this method, obtained after coefficient correlation to circuit
Singlephase earth fault whether occurs to be judged.The circuit structure of method includes three-phase current IA,IB,ICThree inputs and
One connected zero sequence pass filter input；Three-phase voltage UA,UB,UCThree inputs and one be connected thereto what is connect
Zero sequence pass filter input；Electric current and voltage output end are connected with wavelet transform unit respectively, and wavelet transformation point is carried out to signal
Analysis；The sampled signal characteristic quantity extracted through wavelet transformation is connected with coefficient correlation computing unit respectively, to calculate each pair waveform spy
The correlation coefficient ρ of sign amount1、ρ2、ρ3、ρ4、ρ5、ρ6；6 coefficient correlations are respectively outputted to the negative input end of six comparators, adjust
Coefficient value K1=0.5, K2=0.5, K3=0.5, K4=0.5, K5=0.5, K6=0.5 is respectively outputted to the just defeated of respective comparator
Enter end；Six comparator outputs are connected to an adder；The m values that adder is drawn are output to the positive input terminal of comparator, bear
Input is logic setting valve n=5, if comparator totally 6 output in have more than five output be 1, adder output valve m
More than 5, comparator will just output signals to corresponding route selection result indicator and action signal.
After system jam, the FTU of each circuit carries out above calculating, is carried out according to the result of calculation of coefficient correlation
Judge, so as to realize the positioning of faulty line.FTU is by fault information reporting to controlling main website.Control main website analysis faulty line
The fault message that FTU is reported, determines fault section；Substation protection act tripping faulty line after, remote control block switch every
From failure, the power supply of recovery non-faulting section.This method stability is good, is decomposed and judged using a variety of wavelet decomposition algorithms, both sharp
Hypersensitivity with wavelet algorithm to catastrophe point, the error erroneous judgement that a kind of wavelet algorithm is likely to occur is turn avoid, and led to
The correlation analysis for crossing characteristic quantity has reached the purpose of accurate judgement singlephase earth fault outlet.
In addition to the implementation, the present invention can also have other embodiment.It is all to use equivalent substitution or equivalent transformation shape
Into technical scheme, all fall within the protection domains of application claims.
Claims (4)
- A kind of 1. fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure, it is characterised in that：Pass through line The data in road measuring terminals collection three-phase and the electric current and voltage of zero sequence two sampling periods of totally 8 road signals after a failure.It is right Three-phase and zero sequence electric signal carry out wavelet transformation analysis, obtain the characteristic quantity of waveform.Different small echos is used to voltage and current Algorithm is analyzed, and obtains the characteristic quantity of one group of waveform after analyzing the waveform in each two sampling period, 6 groups of ripples are obtained The characteristic quantity of shape, the correlation of every group of characteristic quantity is analyzed, obtains correlation coefficient ρ1、ρ2、ρ3、ρ4、ρ5、ρ6, and respectively with Coefficient correlation setting value is compared.If circuit exceedes setting, quantity result does not meet setting value, judges that the outlet occurs Singlephase earth fault, specifically setting is as follows for the criterion：If ρ1<K1, then a=1, otherwise a=0；If ρ2<K2, then b=1, otherwise b=0；If ρ3<K3, then c=1, otherwise c=0；If ρ4<K4, then d=1, otherwise d=0；If ρ5<K5, then e=1, otherwise e=0；If ρ6<K6, then f=1, otherwise f=0；M=a+b+c+d+e+f >=n；In formula, ρ1、ρ2、ρ3、ρ4、ρ5、ρ6：The coefficient correlation of 6 groups of selected wave character amounts；K1、K2、K3、K4、K5、K6：The setting value of the coefficient correlation of 6 groups of selected wave character amounts；A, b, c, d, e, m, n：Decision logic amount.
- 2. the fault line selection method for single-phase-to-ground fault according to claim 1 based on wavelet character amount correlation after failure, its It is characterised by：The coefficient correlation setting value is 0.35<K1、K2、K3、K4、K5、K6<0.6, the decision logic value n=4 or 5.
- 3. the fault line selection method for single-phase-to-ground fault according to claim 1 based on wavelet character amount correlation after failure, its It is characterised by：The characteristic quantity of the waveform is to carry out wavelet transformation analysis to three-phase and zero sequence electric signal, and its high frequency is calculated Part and low frequency part totally 8 data.
- 4. the fault line selection method for single-phase-to-ground fault according to claim 1 based on wavelet character amount correlation after failure, its It is characterised by：Using circuits below structure, including three-phase current IA,IB,ICThree inputs and a connected zero sequence Pass filter input；Three-phase voltage UA,UB,UCThree inputs and one be connected thereto the zero sequence pass filter input connect；Electricity Stream and voltage output end are connected with wavelet transform unit respectively, and wavelet transformation analysis is carried out to signal；Through wavelet transformation extraction Sampled signal characteristic quantity is connected with coefficient correlation computing unit respectively, to calculate the correlation coefficient ρ of each pair wave character amount1、ρ2、 ρ3、ρ4、ρ5、ρ6；6 coefficient correlations are respectively outputted to the negative input end of six comparators, tuning coefficient value K1、K2、K3、K4、K5、 K6It is respectively outputted to the positive input terminal of respective comparator；Six comparator outputs are connected to an adder；The output of adder The positive input terminal of comparator is connected to, negative input end is setting valve n, comparator output route selection result and action signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710702938.1A CN107632237A (en) | 2017-08-16 | 2017-08-16 | A kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710702938.1A CN107632237A (en) | 2017-08-16 | 2017-08-16 | A kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107632237A true CN107632237A (en) | 2018-01-26 |
Family
ID=61099732
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710702938.1A Pending CN107632237A (en) | 2017-08-16 | 2017-08-16 | A kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107632237A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111077413A (en) * | 2020-01-21 | 2020-04-28 | 山东大学 | Three-phase transient current-based small current grounding system fault phase selection and line selection method |
| CN112083270A (en) * | 2020-08-14 | 2020-12-15 | 昆明理工大学 | Wind power plant current collection line single-phase earth fault line selection method based on correlation coefficient |
| CN116821836A (en) * | 2023-08-31 | 2023-09-29 | 深圳特力自动化工程有限公司 | Multi-sensor-based axle bush abnormal state monitoring method and system |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102788936A (en) * | 2012-09-03 | 2012-11-21 | 安徽理工大学 | Low current grounding fault circuit selection method |
| CN103197202A (en) * | 2013-03-29 | 2013-07-10 | 昆明理工大学 | Distribution network fault line selection method based on wavelet coefficient correlation analysis in three-phase breaking current component characteristic frequency band |
| CN103364684A (en) * | 2013-07-12 | 2013-10-23 | 桐乡市供电局 | Fault line selection method based on wavelet analysis |
| CN104122484A (en) * | 2014-06-10 | 2014-10-29 | 昆明理工大学 | Distribution network fault line selection method based on correlation analysis of zero modal current wavelet coefficients |
| CN104181442A (en) * | 2014-08-21 | 2014-12-03 | 西安交通大学 | Power distribution network single-phase earth fault section locating method based on correlation analysis |
| US20160124031A1 (en) * | 2014-11-04 | 2016-05-05 | Walid G. Morsi Ibrahim | Smart multi-purpose monitoring system using wavelet design and machine learning for smart grid applications |
| KR20160093452A (en) * | 2015-01-29 | 2016-08-08 | 한국 전기안전공사 | Device for detecting insulation defect of mold transformer and method thereby |
| CN107102236A (en) * | 2017-03-24 | 2017-08-29 | 国网浙江余姚市供电公司 | A kind of fault line selection method for single-phase-to-ground fault based on waveform correlation analysis after failure |
-
2017
- 2017-08-16 CN CN201710702938.1A patent/CN107632237A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102788936A (en) * | 2012-09-03 | 2012-11-21 | 安徽理工大学 | Low current grounding fault circuit selection method |
| CN103197202A (en) * | 2013-03-29 | 2013-07-10 | 昆明理工大学 | Distribution network fault line selection method based on wavelet coefficient correlation analysis in three-phase breaking current component characteristic frequency band |
| CN103364684A (en) * | 2013-07-12 | 2013-10-23 | 桐乡市供电局 | Fault line selection method based on wavelet analysis |
| CN104122484A (en) * | 2014-06-10 | 2014-10-29 | 昆明理工大学 | Distribution network fault line selection method based on correlation analysis of zero modal current wavelet coefficients |
| CN104181442A (en) * | 2014-08-21 | 2014-12-03 | 西安交通大学 | Power distribution network single-phase earth fault section locating method based on correlation analysis |
| US20160124031A1 (en) * | 2014-11-04 | 2016-05-05 | Walid G. Morsi Ibrahim | Smart multi-purpose monitoring system using wavelet design and machine learning for smart grid applications |
| KR20160093452A (en) * | 2015-01-29 | 2016-08-08 | 한국 전기안전공사 | Device for detecting insulation defect of mold transformer and method thereby |
| CN107102236A (en) * | 2017-03-24 | 2017-08-29 | 国网浙江余姚市供电公司 | A kind of fault line selection method for single-phase-to-ground fault based on waveform correlation analysis after failure |
Non-Patent Citations (1)
| Title |
|---|
| 李大鹏等: "基于特征频带小波包分析的小电流接地故障选线研究", 《东北电力技术》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111077413A (en) * | 2020-01-21 | 2020-04-28 | 山东大学 | Three-phase transient current-based small current grounding system fault phase selection and line selection method |
| CN112083270A (en) * | 2020-08-14 | 2020-12-15 | 昆明理工大学 | Wind power plant current collection line single-phase earth fault line selection method based on correlation coefficient |
| CN116821836A (en) * | 2023-08-31 | 2023-09-29 | 深圳特力自动化工程有限公司 | Multi-sensor-based axle bush abnormal state monitoring method and system |
| CN116821836B (en) * | 2023-08-31 | 2023-10-27 | 深圳特力自动化工程有限公司 | Multi-sensor-based axle bush abnormal state monitoring method and system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107102236B (en) | A kind of fault line selection method for single-phase-to-ground fault based on waveform correlation analysis after failure | |
| CN108181547B (en) | Dynamic time bending distance fault section positioning method based on time sequence compression | |
| CN105242176B (en) | A kind of low current neutral grounding system fault localization method for being suitable for monitoring branched line | |
| CN103713237B (en) | A kind of power system transmission line short trouble diagnostic method | |
| Kulkarni et al. | Incipient fault location algorithm for underground cables | |
| Khodadadi et al. | A noncommunication adaptive single-pole autoreclosure scheme based on the ACUSUM algorithm | |
| CN103364684B (en) | Fault line selection method based on wavelet analysis | |
| CN107085165B (en) | A kind of distribution network line is the same as the successive ground fault line selecting method of famous prime minister's two o'clock | |
| CN103995172B (en) | Method for on-line monitoring of load current of GIS bus of substation | |
| CN201234124Y (en) | Single-phase grounding failure wire selection automatic processing equipment for low current grounding system | |
| CN103439633A (en) | Low-current ground fault line selection device | |
| CN111812451A (en) | Phase current transient fault component-based distributed line selection method for power distribution network | |
| CN108599114A (en) | A kind of high voltage ac/dc combined hybrid system alternating current circuit transient state direction protection method | |
| CN105510760A (en) | Method for detecting short circuit fault data based on wavelet analysis | |
| CN104375025A (en) | Diagnostic method for ferromagnetic resonance in neutral non-grounding 10kV system | |
| CN107632237A (en) | A kind of fault line selection method for single-phase-to-ground fault based on wavelet character amount correlation after failure | |
| CN103344911B (en) | A kind of high-voltage direct-current switch disconnection overall process state identification method | |
| CN106646130A (en) | Active power distribution network fault positioning method and system based on current polarity comparison | |
| CN103558460A (en) | Medium-voltage system arc fault detection device | |
| CN104090211B (en) | A kind of online test method of distribution line high resistance earthing fault | |
| CN112748362B (en) | Small current ground fault detection method based on combination of VMD and grey correlation degree | |
| CN110579679A (en) | power distribution network line fault detection system based on negative sequence current vector analysis and detection method thereof | |
| CN103823153A (en) | 35kV distribution network single-phase earth fault type judging device | |
| CN111381127A (en) | Method and device for single-phase earth fault and insulation monitoring of mine power supply system | |
| CN104655991A (en) | Power system fault matching method based on mutant point dejection combinational algorithm |
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 | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20180126 |