CN109324262A - A kind of fault positioning method for transmission line based on TT transformation and velocity of wave optimization - Google Patents
A kind of fault positioning method for transmission line based on TT transformation and velocity of wave optimization Download PDFInfo
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- CN109324262A CN109324262A CN201811200510.8A CN201811200510A CN109324262A CN 109324262 A CN109324262 A CN 109324262A CN 201811200510 A CN201811200510 A CN 201811200510A CN 109324262 A CN109324262 A CN 109324262A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/088—Aspects of digital computing
Abstract
The invention discloses a kind of fault positioning method for transmission line optimized based on TT transformation and velocity of wave, characterized in that includes the following steps: 1) fault-signal extraction；2) signal decouples；3) 1 line wave Singularity detection of failure；4) velocity of wave optimizes；5) fault section determines；6) fault localization.This method can improve traveling wave inflection point detection precision, and then improve measuring distance of transmission line fault precision, applied widely.
Description
Technical field
The present invention relates to Power System Faults Detection field, specifically a kind of power transmission line based on TT transformation and velocity of wave optimization
Road fault distance-finding method.
Background technique
With the continuous development of society, the effect that electric energy plays in human society is increasing, stablizes, reliable conveying
Electric energy becomes the topic of people's growing interest.Electric power transmission line is as transmission electric energy key components, how in its generation
When failure quickly, accurately detect abort situation, for effectively solving due to trouble-shooting position caused by for a long time have a power failure ask
Topic, the reliability and stability for improving power supply system are all of great significance.
Fault positioning method for transmission line is broadly divided into impedance method and traveling wave method.Impedance method mainly pass through fault inspecting and
Then impedance value between measurement point calculates fault distance according to the impedance of route unit length；Traveling wave rule is to pass through survey
It measures the catadioptric time of traveling wave between fault point and measurement point, then calculates abort situation away from formula by correlative measurement.With impedance method phase
Than traveling wave method has stronger anti-interference ability, by system operation mode, line construction, transition impedance and load fluctuation etc.
The influence of factor is minimum, has good measurement accuracy, therefore be widely used in measuring distance of transmission line fault.
It the use of the key that traveling wave method carries out fault localization to transmission line of electricity is accurately to find fault traveling wave in the prominent of measurement point
Become the time, there is scholar to propose to analyze the current traveling wave of failure using wavelet transformation, using the small echo under basic frequency scale
The modulus maximum point of transformation comes the arrival time of representing fault traveling wave, but wavelet analysis method application when by morther wavelet and decomposition
The influence of scale, if selection is improper, detection accuracy is a greater impact.To overcome the shortcomings of wavelet transformation, then there is scholar
It is proposed that this method efficiently solves wavelet transformation can not be adaptive using having adaptive Hilbert-Huang distance measuring method
The problem of, however this method there are modal overlap, envelope fitting the problems such as, have larger impact to range accuracy.Because of S-transformation
With powerful time frequency analysis ability, occurred in succession based on S-transformation fault position method later, transmission line malfunction precision is shown
It writes and is promoted, measuring distance of transmission line fault enters a rapid development epoch.However, the basic transformation functional form of S-transformation is fixed,
Its window width " relatively fixed " can not achieve automatic adjusument, therefore S-transformation has certain deficiency.At the same time, current majority
Line fault ranging calculating mostly uses velocity of wave fixation, this influences the accurate of measuring distance of transmission line fault to a certain extent
Property, therefore, current fault positioning method for transmission line still has certain limitation.
Summary of the invention
The purpose of the present invention is in view of the deficiencies of the prior art, and provide a kind of transmission of electricity based on TT transformation and velocity of wave optimization
Circuit fault distance measurement.This method can improve traveling wave inflection point detection precision, and then improve measuring distance of transmission line fault essence
Degree, it is applied widely.
Realizing the technical solution of the object of the invention is:
A kind of fault positioning method for transmission line based on TT transformation and velocity of wave optimization, unlike the prior art, packet
Include following steps:
1) fault-signal extracts: establishing both-end transmission line of electricity line fault ranging model, the model is 500kV power transmission line
Road, wherein the end M, N-terminal are respectively the both ends of transmission line of electricity, and L is the length of route MN, and F is line fault point, with route zero sequence electricity
Whether stream increases severely as the criterion for judging line failure, if zero-sequence current increases severely, extracts 0.04s before zero-sequence current increases severely
And the route both end voltage current signal after sharp increase between 0.06s；
2) signal decouples: according to phase mode transformation matrix, to the three-phase electricity coupled in the fault localization model of step 1) foundation
Pressure, current signal decoupling, obtain mutually independent travelling wave signal, mutually independent travelling wave signal is respectively 0 mould, 1 mould, 2 moulds, institute
State phase mode transformation matrix are as follows:
3) 1 line wave Singularity detection of failure: being converted using TT, detects that the 1 line wave of failure of step 2) solution decoupling is prominent
Height is mutated peak value by finding traveling wave, determines that fault traveling wave catastrophe point corresponds to the time；
4) velocity of wave optimize: by step 3) can be obtained step 1) foundation fault localization model in the end M receive first three
The 1 line wave catastrophe point time of failure corrects velocity of wave using velocity of wave optimization formula (1) by analyzing traveling wave catadioptric process, with
Guarantee the accuracy of velocity of wave, velocity of wave optimizes formula (1) are as follows:
In formula, L is route MN length, tM1、tM2And tM3Respectively 1 traveling wave of failure for the first time, second, third time reach the end M
Time；
5) fault section determines: using the simultaneous techniques in global positioning system, that is, GPS, by route from one from central point O
It is divided into two, judges position of failure point close to the end M or N-terminal according to both-end method；
6) fault localization: according to different fault sections, fault localization calculation formula can be divided into following three:
(1) position of failure point occurs at OM sections of route, wherein O point is the midpoint of transmission line of electricity, fault point F to the end bus M
Distance by single-ended principle can be formula (2):
In formula, V is the velocity of wave of optimization, tM1And tM2Respectively 1 line wave of failure for the first time, second time for reaching the end M；
(2) point O point in the line occurs for abort situation, and the distance of fault point F to the end bus M is L/2；
(3) abort situation occurs at ON sections of route, wherein O point is the midpoint of transmission line of electricity, fault point F to the end bus M
It is formula (3) that distance can be obtained by single-ended principle:
In formula, L is route MN length, and V is the velocity of wave of optimization, tM1And tM2Respectively 1 line wave of failure for the first time, second
The time for reaching the end M optimizes in conjunction with the velocity of wave that step 3) obtains the M termination fault traveling wave mutation time point received and step 4),
Fault section can determine by step 5), abort situation can detect that by formula (2), the formula (3) in step 6), to realize defeated
Line fault distance measuring.
TT is converted in 2003 and is proposed by Pinnegar, by carrying out Fourier inversion to S-transformation.Compared to
S-transformation, TT convert signal time-domain analysis ability it is stronger, it be in the one-dimensional time two dimension constantly indicate；In frequency-domain analysis
Aspect, the high frequency section of signal is concentrated on the diagonal positions of TT transformation by it, is had good frequency analysis ability, is utilized it
Advantage, TT transformation have very high precision in high-frequency harmonic detection, achieve in the fields such as mechanical fault detection at present good
Good effect.
TT converts diagonal entry is defined as:
TT (t, t)=F-1{H(f)G(f)} (4)
In formula, F-1For inverse Fourier transform, H (f) is the Fourier transformation of input signal h (t), and G (f) passes through integral transformation
It can obtain:
G (f)=- 2c π2|f| (5)
In formula, c is a constant unrelated with frequency, it is clear that within the scope of signal effective band, G (f) and | f | and at just
Than, | f | bigger, G (f) is bigger, and TT (t, t) is also bigger, therefore has more significant feature in high frequency section.
The technical program is with obtaining independent failure line wavelength-division and line by decoupling to the travelling wave signal that breaks down
Line wave component, since line line wave attenuation is smaller, 1 line wave in this programme selection line line wave carries out Singularity detection,
Then use TT change detection failure catastrophe point, determine first three failure mutation time point to the time between measurement point, then
Velocity of wave is corrected using these three failure mutation time points, the transmission speed of current traveling wave in the line is determined, finally further according to list
End travelling wave ranging formula can calculate abort situation, realize measuring distance of transmission line fault.
This method mainly optimizes integration the TT transformation with strong constantly analysis ability and velocity of wave, reduces because of mutation time
Detection inaccuracy and the velocity of wave inconsistence problems of traveling wave under various circumstances, improve traveling wave inflection point detection precision, enhance algorithm
The scope of application.
The technical scheme is characterized in that:
1. converting using TT, other methods are compared, TT converts lossless reciprocal, has powerful constantly analysis ability and high frequency
Focus characteristics；
It, can be more efficient, accurately by analyzing Transient Fault Signal for EHV Transmission Lines 2. the technical program belongs to transient method
Detect the catastrophe point that is out of order；
3. velocity of wave optimization be to fault traveling wave signal Transmission Lines speed optimization, it is ensured that under specific condition,
The characteristics of velocity of wave changes realizes that adaptive velocity of wave is adjusted, effectively improves measuring distance of transmission line fault precision.
This method can improve traveling wave inflection point detection precision, and then improve measuring distance of transmission line fault precision, be applicable in model
It encloses wide.
Detailed description of the invention
Fig. 1 is embodiment method flow schematic diagram；
Fig. 2 is fault diagnosis model schematic illustration in embodiment；
Fig. 3-1 is in embodiment close to the end M fault section waveform catadioptric schematic diagram；
Fig. 3-2 is in embodiment close to N-terminal fault section waveform catadioptric schematic diagram.
Specific embodiment
The contents of the present invention are further elaborated with reference to the accompanying drawings and examples, but are not to limit of the invention
It is fixed.
Embodiment:
Referring to Fig.1, a kind of fault positioning method for transmission line based on TT transformation and velocity of wave optimization, includes the following steps:
1) fault-signal extracts: establishing both-end transmission line of electricity line fault ranging model, the model is 500kV power transmission line
Road, wherein the end M, N-terminal are respectively the both ends of transmission line of electricity, and L is the length of route MN, and F is line fault point, as shown in Fig. 2, this
In example, at distance M end 60km, singlephase earth fault, fault resistance 10 occurs6Ω, with route zero-sequence current whether
Increase severely as the criterion for judging line failure, if zero-sequence current increases severely, extracts 0.04s and sharp increase before zero-sequence current increases severely
Route both end voltage current signal between 0.06s afterwards；
2) signal decouples: according to phase mode transformation matrix, to the three-phase electricity coupled in the fault localization model of step 1) foundation
Pressure, current signal decoupling, obtain mutually independent travelling wave signal, mutually independent travelling wave signal is respectively 0 mould, 1 mould, 2 moulds, institute
State phase mode transformation matrix are as follows:
3) 1 line wave Singularity detection of failure: being converted using TT, detects that the 1 line wave of failure of step 2) solution decoupling is prominent
Height is mutated peak value by finding traveling wave, determines that fault traveling wave catastrophe point corresponds to the time；
4) velocity of wave optimizes: first three failure 1 at the end M in the fault localization model of step 1) foundation can be obtained by step 3)
The line wave catastrophe point time corrects velocity of wave using velocity of wave optimization formula (1) by analyzing traveling wave catadioptric process, to guarantee
The accuracy of velocity of wave, velocity of wave optimize formula (1) are as follows:
In formula, L is route MN length, tM1、tM2And tM3Respectively 1 line wave of failure for the first time, second, third time reach M
The time at end；
5) fault section determines: using the simultaneous techniques in global positioning system, that is, GPS, by route from one from central point O
It is divided into two, judges position of failure point close to the end M or N-terminal according to both-end method；
6) fault localization: according to different fault sections, fault localization calculation formula can be divided into following three:
(1) position of failure point occurs at OM sections of route, as shown in figure 3-1, wherein O point is the midpoint of transmission line of electricity, failure
It is formula (2) that the distance at point F to the end bus M can be obtained by single-ended principle:
In formula, V is the velocity of wave of optimization, tM1And tM2Respectively 1 line wave of failure for the first time, second time for reaching the end M；
(2) point O point in the line occurs for abort situation, and the distance of fault point F to the end bus M is L/2；
(3) abort situation occurs at ON sections of route, as shown in figure 3-2, wherein O point is the midpoint of transmission line of electricity, fault point
It is formula (3) that the distance at F to the end bus M can be obtained by single-ended principle:
In formula, L is route MN length, and V is the velocity of wave of optimization, tM1And tM2Respectively 1 line wave of failure for the first time, second
The time for reaching the end M optimizes in conjunction with the velocity of wave that step 3) obtains the M termination fault traveling wave mutation time point received and step 4),
Fault section can determine by step 5), abort situation can detect that by formula (2), the formula (3) in step 6), to realize defeated
Line fault distance measuring.
Claims (1)
1. a kind of fault positioning method for transmission line based on TT transformation and velocity of wave optimization, characterized in that include the following steps:
1) fault-signal extracts: both-end transmission line of electricity line fault ranging model is established, the model is 500kV transmission line of electricity,
Wherein the end M, N-terminal are respectively the both ends of transmission line of electricity, and L is the length of route MN, and F is line fault point, with route zero-sequence current
Whether sharp increase is as the criterion for judging line failure, if zero-sequence current increases severely, extract before zero-sequence current increases severely 0.04s and
Route both end voltage current signal after sharp increase between 0.06s；
2) signal decouples: according to phase mode transformation matrix, the three-phase voltage, the electricity that are coupled in the fault localization model established to step 1)
Signal decoupling is flowed, obtains mutually independent travelling wave signal, mutually independent travelling wave signal is 0 mould, 1 mould, 2 moulds, the phase respectively
Modular transformation matrix are as follows:
3) 1 line wave Singularity detection of failure: being converted using TT, is detected 1 line wave catastrophe point of step 2) solution decoupling, is passed through
It finds traveling wave and is mutated peak value, determine that fault traveling wave catastrophe point corresponds to the time；
4) velocity of wave optimizes: first three failure 1 that the end M receives in the fault localization model of step 1) foundation can be obtained by step 3)
The line wave catastrophe point time corrects velocity of wave using velocity of wave optimization formula (1) by analyzing traveling wave catadioptric process, to guarantee
The accuracy of velocity of wave, velocity of wave optimize formula (1) are as follows:
In formula, L is route MN length, tM1、tM2And tM3Respectively 1 line wave of failure for the first time, second, third time reach the end M
Time；
5) fault section determines: using the simultaneous techniques in global positioning system, that is, GPS, route is divided into two from midpoint,
Judge position of failure point close to the end M or N-terminal according to both-end method；
6) fault localization: according to different fault sections, fault localization calculation formula can be divided into following three:
(1) position of failure point occur at OM section of route, wherein O point for transmission line of electricity midpoint, fault point F to the end bus M away from
It is formula (2) from that can be obtained by single-ended principle:
In formula, V is the velocity of wave of optimization, tM1And tM2Respectively 1 line wave of failure for the first time, second time for reaching the end M；
(2) point O point in the line occurs for abort situation, and the distance of fault point F to the end bus M is L/2；
(3) abort situation occurs at ON sections of route, wherein O point is the midpoint of transmission line of electricity, distance of the fault point F to the end bus M
Can be obtained by single-ended principle is formula (3):
In formula, L is route MN length, and V is the velocity of wave of optimization, tM1And tM2Respectively 1 line wave of failure for the first time, second reach M
The time at end optimizes in conjunction with the velocity of wave that step 3) obtains the M termination fault traveling wave mutation time point received and step 4), by step
5) it can determine fault section, then abort situation can detect that by formula (2), the formula (3) in step 6), to realize power transmission line
Road fault localization.
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| CN113219296A (en) * | 2021-03-22 | 2021-08-06 | 昆明理工大学 | Transmission line traveling wave fault data segment self-adaptive intercepting method |
| CN113281617A (en) * | 2021-06-08 | 2021-08-20 | 中国民航大学 | Weak fault diagnosis method for airplane cable |
| CN115184739A (en) * | 2022-09-14 | 2022-10-14 | 中国电力科学研究院有限公司 | Traveling wave distance measurement method and system considering comprehensive parameter change |
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| CN113281617A (en) * | 2021-06-08 | 2021-08-20 | 中国民航大学 | Weak fault diagnosis method for airplane cable |
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