CN112415328B - Fault positioning method and system based on cubic B spline wavelet and interpolation algorithm - Google Patents
Fault positioning method and system based on cubic B spline wavelet and interpolation algorithm Download PDFInfo
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- 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
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Abstract
The disclosure provides a fault positioning method and system based on a cubic B spline wavelet and interpolation algorithm, comprising the following steps: acquiring current traveling wave signals at two ends of a line, and extracting line mode components of the traveling wave signals; constructing a cubic B spline wavelet as a wavelet basis, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency; calculating the instantaneous energy of the harmonic component with the highest frequency to obtain the abrupt change moment of the energy; extracting a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; and positioning the fault position according to the arrival time of the traveling wave. The method comprises the steps of constructing a cubic B spline wavelet as a wavelet base to carry out wavelet decomposition, determining the arrival time of a wave head through a Teager energy operator and a Hermite interpolation method, and forming a practical algorithm for positioning the fault of the power transmission line, so that the accuracy of identifying the first mutation point of the high-frequency signal can be greatly improved.
Description
Technical Field
The disclosure relates to the technical field of power system line protection, in particular to a fault positioning method and system based on cubic B-spline wavelet and interpolation algorithm.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The transmission line plays a role in conveying electric energy, is an important ring in the electric power system, and is the place with the largest faults. If the fault position can be rapidly and accurately positioned after the fault, the reliability of the power system can be improved, a large amount of manpower and material resources can be saved, great economic benefit is brought, and the fault positioning is particularly important.
The current fault positioning methods can be roughly divided into two types, one type is a fault analysis method based on power frequency quantity, including an impedance method, a voltage method and the like; the other is a traveling wave method based on transient components. Because of the limitation of the power frequency quantity and the abundant transient quantity in fault current and voltage, the traveling wave method is a hot spot of current research. The inventor finds that the method for determining the position of the first mutation point of the high-frequency signal by utilizing wavelet decomposition in the traveling wave method is the current mainstream method. However, the method is difficult to accurately determine the mutation points, so that the positioning accuracy is insufficient, and the time for the mutation points to determine the traveling wave to reach the measurement points cannot be accurately identified. Therefore, it is necessary to study a method capable of accurately identifying the point of mutation and determining the time when the traveling wave reaches the measuring point.
Disclosure of Invention
In order to solve the problems, the disclosure provides a fault positioning method and a system based on a cubic B-spline wavelet and an interpolation algorithm, which are characterized in that the cubic B-spline wavelet is constructed to be used as a wavelet basis for wavelet decomposition, and then the arrival time of a wave head is determined by a Teager energy operator and a Hermite interpolation method to form a practical algorithm for positioning the fault of a power transmission line, so that the accuracy of identifying the first mutation point of a high-frequency signal can be greatly improved.
In order to achieve the above purpose, the present disclosure adopts the following technical scheme:
one or more embodiments provide a fault localization method based on a cubic B-spline wavelet and interpolation algorithm, including the steps of:
Acquiring current traveling wave signals at two ends of a line, and extracting line mode components of the traveling wave signals;
constructing a cubic B spline wavelet as a wavelet basis, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency;
Calculating the instantaneous energy of the harmonic component with the highest frequency to obtain the abrupt change moment of the energy;
extracting a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; and positioning the fault position according to the arrival time of the traveling wave.
One or more embodiments provide a fault localization system based on a cubic B-spline wavelet and interpolation algorithm, comprising:
the acquisition module is used for: the system is configured to acquire current traveling wave signals at two ends of a line and extract line mode components of the traveling wave signals;
And a decomposition module: the method comprises the steps of constructing a cubic B spline wavelet as a wavelet basis, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency;
An energy calculation module: the method comprises the steps of calculating instantaneous energy of harmonic components with highest frequencies to obtain abrupt moment of energy;
interpolation output module: the method comprises the steps of being configured to extract a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; and positioning the fault position according to the arrival time of the traveling wave.
An electronic device comprising a memory and a processor and computer instructions stored on the memory and running on the processor, which when executed by the processor, perform the steps of the method described above.
A computer readable storage medium storing computer instructions which, when executed by a processor, perform the steps of the method of claim.
Compared with the prior art, the beneficial effects of the present disclosure are:
The method adopts cubic B spline wavelet as wavelet basis for wavelet decomposition, and is more sensitive to the identification of wave head mutation points than the traditional wavelet basis function; meanwhile, the traveling wave head is identified by adopting an energy calculation method, namely a method of combining a Teager energy operator and Hermite interpolation, the moment when the wave head reaches a measuring end is determined by an energy mutation angle, the accuracy of the wave head arrival moment is further improved by utilizing an interpolation method, and the defect of single wave head identification by utilizing wavelet decomposition is overcome.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate and explain the exemplary embodiments of the disclosure and together with the description serve to explain and do not limit the disclosure.
FIG. 1 is a flow chart of a fault location method of embodiment 1 of the present disclosure;
fig. 2 is a schematic diagram of a double-ended power transmission line ranging according to embodiment 1 of the present disclosure;
FIG. 3 (a) is a cubic B-spline scale function of example 1 of the present disclosure;
FIG. 3 (b) is a wavelet function image of example 1 of the present disclosure;
fig. 4 (a) is the highest frequency component of the double-ended power transmission line a-side fault current of embodiment 1 of the present disclosure after wavelet decomposition;
Fig. 4 (B) is the highest frequency component of the B-terminal fault current of the double-ended power transmission line of embodiment 1 of the present disclosure after wavelet decomposition;
fig. 5 (a) is a graph of instantaneous energy of a double-ended power transmission line a-side wavelet of embodiment 1 of the present disclosure;
Fig. 5 (B) is a B-terminal wavelet instantaneous energy diagram of a double-ended power transmission line of embodiment 1 of the present disclosure;
fig. 6 (a) is a graph constructed by a Hermite interpolation method for the a-side of the double-ended power transmission line of embodiment 1 of the present disclosure;
FIG. 6 (B) is a plot constructed by the Hermite interpolation method for the B-side of the double-ended power transmission line of example 1 of the present disclosure;
Fig. 7 (a) is the highest frequency component of the double-ended power transmission line a-side of embodiment 1 of the present disclosure using db4 wavelet basis for wavelet decomposition;
fig. 7 (B) is the highest frequency component of the B-side of the double-ended power transmission line of embodiment 1 of the present disclosure using the db4 wavelet basis for wavelet decomposition.
Detailed Description
The disclosure is further described below with reference to the drawings and examples.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments in accordance with the present disclosure. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof. It should be noted that, without conflict, the various embodiments and features of the embodiments in the present disclosure may be combined with each other. The embodiments will be described in detail below with reference to the accompanying drawings.
Example 1
In the technical solution disclosed in one or more embodiments, as shown in fig. 1, a fault locating method based on a cubic B-spline wavelet and interpolation algorithm includes the following steps:
step 1, acquiring current traveling wave signals at two ends of a line, and extracting line mode components of the traveling wave signals;
Step 2, constructing a cubic B spline wavelet as a wavelet base, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency;
step 3, calculating the instantaneous energy of the harmonic component with the highest frequency to obtain the abrupt change moment of the energy;
Step 4, extracting a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; and positioning the fault position according to the arrival time of the traveling wave.
In the embodiment, the cubic B spline wavelet is used as the wavelet basis of wavelet decomposition, and compared with the traditional wavelet basis function, the embodiment is more sensitive to the identification of the wave head mutation points; meanwhile, the traveling wave head is identified by adopting an energy calculation method, namely a method of combining a Teager energy operator and Hermite interpolation, the moment when the wave head reaches a measuring end is determined by an energy mutation angle, the accuracy of the wave head arrival moment is further improved by utilizing an interpolation method, and the defect of single wave head identification by utilizing wavelet decomposition is overcome.
As shown in fig. 2, power supplies are respectively provided at two ends of the line A, B, and when a fault occurs in the power transmission line, fault current traveling wave signals at two ends of A, B are collected.
In step 1, current traveling wave signals at two ends of a line are collected, current components are decoupled by adopting Karenbauer phase-mode transformation matrix, and an alpha-mode component i α of the traveling wave signals obtained by decoupling is extracted, specifically as follows:
The relation of the phase-mode transformation and the inverse transformation in the time domain is shown in the formula (1):
the Karenbauer phase-mode transformation matrix is shown as (2):
decoupling the fault current can result in the following expression:
Wherein i a,ib,ic is the fault current at two ends of the acquired line, and i 0,iα,iβ is the decomposed 0-mode and line-mode components. Because the 0-mode component is unstable, the alpha-mode component i α in the line-mode component is selected for the next wavelet decomposition.
In step 2, constructing a cubic B spline wavelet, and carrying out wavelet decomposition on alpha-mode components of the currents at two ends by taking the cubic B spline wavelet as a wavelet base to obtain the component with the highest frequency.
For m times B spline wavelet:
wherein N 0 (t) is a primary B-spline wavelet:
the scale function of an m-th order B-spline wavelet is defined as:
When m is an odd number, k=0; when m is even, k=1.
As shown in fig. 3 (a) -3 (B), the cubic B spline wavelet is constructed by m=3 and k=0 in the above formula (4) and formula (6):
wherein N m (t) is an m-th order B-spline wavelet, M is a natural number for the corresponding scale function; t is time and ω is frequency.
And performing wavelet decomposition and reconstruction on alpha-mode components of the current at two ends by taking the constructed cubic B spline wavelet as a wavelet base, wherein the highest frequency component is shown in figure 4.
In step 3, calculating the instantaneous energy of the harmonic component with the highest frequency to obtain the energy mutation moment, and specifically adopting a Teager energy operator to calculate the instantaneous energy value.
The instantaneous frequency of each point is calculated using the discrete time signal definition of the Teager energy operator.
Specifically, for discrete-time signals, the Teager energy operator is defined as:
where x (n), x (n-1), and (n+1) represent sampling points of the discrete signal.
The instantaneous energy of the signal extracted by the Teager energy operator in this embodiment is shown in fig. 5.
According to the embodiment, the Teager energy operator is adopted for energy extraction, is a nonlinear energy operator, can calculate the instantaneous energy at any moment only by data at three moments, can improve the resolution of the instantaneous variation of signals, and can effectively monitor the mutation moment of the traveling wave head of the traveling wave signal in the embodiment.
In the step 4, a plurality of points around the first mutation energy are extracted, a Hermite interpolation calculation construction curve is adopted, the maximum value point of the curve is identified, and the arrival time of the traveling wave is determined; and positioning the fault position according to the arrival time of the traveling wave.
The Hermite interpolation method can enable interpolation points to be on a constructed interpolation function, and a constructed curve is smooth and continuous at the interpolation points, so that the change characteristics of data can be described more accurately. The method is used for constructing a curve for the signals processed by the Teager energy operators, and the moment corresponding to the maximum value of the curve is selected as the arrival moment of the traveling wave, so that errors caused by wavelet decomposition and reconstruction can be reduced, the wave head can be identified more accurately, and the arrival moment of the traveling wave can be determined.
The Hermite interpolation method specifically comprises the following steps: for n distinct points (x i,yi) (i=1, 2,3,..n), the derivative y' 0 of the first point is known, with an interpolation polynomial
H(x)＝y0+f[x0,x1](x-x0)+f[x0,x1,x2](x-x0)(x-x1)+...+
f[x0,x1,x2,...xn](x-x0)(x-x1)...(x-xn-1)+A(x-x0)(x-x1)...(x-xn-1) (8)
Wherein ,f[x0,x1],f[x0,x1,x2],...,f[x0,x1,x2,...xn] is the difference quotient.
A in the formula (8) can be obtained by the following formula;
The Hermite interpolation curve constructed in this embodiment is shown in fig. 6, and the corresponding time of the maximum point of the obtained curve is the further accurate arrival time of the wave head.
The fault location method can be adopted according to the arrival time of the traveling wave, and specifically comprises the following steps:
And calculating the distance from the fault point to the left end of the line through double-end ranging, wherein the time of occurrence of the fault is assumed to be t 0, the time of arrival of the fault traveling wave at the two ends of the line is respectively t 1、t2, the wave speed is v, and the total length of the line is L at the position of the fault point, which is away from the left end x of the line.
The specific double-end ranging formula is as follows:
x＝v(t1-t0)
L-x＝v(t2-t0)
in the embodiment, the cubic B spline wavelet is used as the wavelet basis of wavelet decomposition, the travelling wave head is identified by combining the Teager energy operator and Hermite interpolation, the moment when the wave head reaches the measuring end is determined by the angle of energy mutation, the accuracy of the wave head arrival moment is further improved by using the interpolation method, and the defect of single wave head identification by using wavelet decomposition is overcome. For possible short-circuit faults of the line, the range error can be reduced to be less than 300m in theory.
Simulation experiments were performed to illustrate the effects of this embodiment as follows:
and constructing a power transmission line pscad model, wherein the total length of the line is 200km, the traveling wave speed is 292.526km/ms, fault data are obtained, and the fault positioning result is shown in table 1.
TABLE 1 simulation results
The conventional algorithm in the table adopts db4 wavelet to carry out wavelet decomposition and reconstruction and directly identifies the position of the mutation point in the reconstructed waveform, as shown in fig. 7, and the fault location precision is about 2 km. The algorithm adopted by the invention has the fault positioning accuracy within 300m for different fault types and distances, and can be seen that the algorithm adopted by the invention has higher accuracy compared with the conventional travelling wave ranging algorithm.
Example 2
Based on the method of embodiment 1, this embodiment proposes a fault locating system based on a cubic B-spline wavelet and interpolation algorithm, including:
the acquisition module is used for: the system is configured to acquire current traveling wave signals at two ends of a line and extract line mode components of the traveling wave signals;
And a decomposition module: the method comprises the steps of constructing a cubic B spline wavelet as a wavelet basis, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency;
An energy calculation module: the method comprises the steps of calculating instantaneous energy of harmonic components with highest frequencies to obtain abrupt moment of energy;
interpolation output module: the method comprises the steps of being configured to extract a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; and positioning the fault position according to the arrival time of the traveling wave.
Example 3
The present embodiment provides an electronic device comprising a memory and a processor, and computer instructions stored on the memory and running on the processor, which when executed by the processor, perform the steps recited in the method of embodiment 1.
Example 4
The present embodiment provides a computer readable storage medium storing computer instructions that, when executed by a processor, perform the steps of the method of embodiment 1.
The electronic device provided by the present disclosure may be a mobile terminal and a non-mobile terminal, where the non-mobile terminal includes a desktop computer, and the mobile terminal includes a Smart Phone (such as an Android Phone, an IOS Phone, etc.), a Smart glasses, a Smart watch, a Smart bracelet, a tablet computer, a notebook computer, a personal digital assistant, and other mobile internet devices capable of performing wireless communication.
It should be appreciated that in this disclosure, the processor may be a central processing unit, CPU, the processor may also be other general purpose processors, digital signal processors, DSPs, application specific integrated circuits, ASICs, off-the-shelf programmable gate arrays, FPGAs, or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
The memory may include read only memory and random access memory and provide instructions and data to the processor, and a portion of the memory may also include non-volatile random access memory. For example, the memory may also store information of the device type.
In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or by instructions in the form of software. The steps of a method disclosed in connection with the present disclosure may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in a processor for execution. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor reads the information in the memory and, in combination with its hardware, performs the steps of the above method. To avoid repetition, a detailed description is not provided herein. Those of ordinary skill in the art will appreciate that the elements of the various examples described in connection with the embodiments disclosed herein, i.e., the algorithm steps, can be implemented as electronic hardware, or as a combination of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.
It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.
In several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the units is merely a division of one logic function, and there may be additional divisions when actually implemented, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. In addition, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interface, device or unit indirect coupling or communication connection, which may be in electrical, mechanical or other form.
The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present disclosure may be embodied in essence or a part contributing to the prior art or a part of the technical solution, or in the form of a software product stored in a storage medium, including several instructions for causing a computer device (which may be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in the embodiments of the present disclosure. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.
The foregoing description of the preferred embodiments of the present disclosure is provided only and not intended to limit the disclosure so that various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.
While the specific embodiments of the present disclosure have been described above with reference to the drawings, it should be understood that the present disclosure is not limited to the embodiments, and that various modifications and changes can be made by one skilled in the art without inventive effort on the basis of the technical solutions of the present disclosure while remaining within the scope of the present disclosure.
Claims (7)
1. The fault positioning method based on the cubic B spline wavelet and interpolation algorithm is characterized by comprising the following steps:
Acquiring current traveling wave signals at two ends of a line, and extracting line mode components of the traveling wave signals;
Karenbauer the phase-to-mode transformation matrix is as follows:
decoupling the current component by adopting Karenbauer phase-mode transformation matrix, and extracting the alpha-mode component of the traveling wave signal obtained by decoupling;
constructing a cubic B spline wavelet as a wavelet basis, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency; the three times B-spline wavelet constructed is:
In the method, in the process of the invention, Is a B-spline wavelet of m times,M is a natural number for the corresponding scale function; t is time, ω is frequency;
Meanwhile, the traveling wave head is identified by adopting an energy calculation method, namely a method of combining a Teager energy operator and Hermite interpolation, and the moment when the wave head reaches a measuring end is determined by an energy mutation angle, specifically comprising the following steps:
calculating the instantaneous energy of the harmonic component with the highest frequency to obtain the abrupt change moment of the energy; calculating an instantaneous energy value by adopting a Teager energy operator;
Extracting a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; locating the fault position according to the arrival time of the traveling wave;
The Hermite interpolation method specifically comprises the following steps: for n distinct points (x i,yi) (i=1, 2,3,..n), the derivative of the first point is known With interpolation polynomials
(8)
In the method, in the process of the invention,Is a difference quotient;
(9)
a in the formula (8) can be obtained by the following formula;
(10)。
2. The fault locating method based on the cubic B-spline wavelet and interpolation algorithm as claimed in claim 1, wherein the fault locating method is characterized by: the instantaneous frequency of each point is calculated using the discrete time signal definition of the Teager energy operator.
3. The fault locating method based on the cubic B-spline wavelet and interpolation algorithm as claimed in claim 2, wherein the fault locating method is characterized by: for discrete-time signals, the Teager energy operator is defined as:
(7)
where x (n), x (n-1), x (n+1) represent the sampling points of the discrete signal.
4. The fault locating method based on the cubic B-spline wavelet and interpolation algorithm as claimed in claim 1, wherein the fault locating method is characterized by: positioning according to arrival time of travelling wave the fault location adopts a double-end ranging method.
5. The fault locating system based on the cubic B-spline wavelet and interpolation algorithm adopts the fault locating method based on the cubic B-spline wavelet and interpolation algorithm as set forth in claim 1, and is characterized by comprising the following steps:
the acquisition module is used for: the system is configured to acquire current traveling wave signals at two ends of a line and extract line mode components of the traveling wave signals;
And a decomposition module: the method comprises the steps of constructing a cubic B spline wavelet as a wavelet basis, and carrying out wavelet decomposition on the extracted linear mode component to obtain a harmonic component with highest frequency;
An energy calculation module: the method comprises the steps of calculating instantaneous energy of harmonic components with highest frequencies to obtain abrupt moment of energy;
interpolation output module: the method comprises the steps of being configured to extract a plurality of points near the first mutation energy, performing Hermite interpolation calculation to construct a curve, identifying the maximum point of the curve, and determining the arrival time of the traveling wave; and positioning the fault position according to the arrival time of the traveling wave.
6. An electronic device comprising a memory and a processor and computer instructions stored on the memory and running on the processor, which when executed by the processor, perform the steps of the method of any of claims 1-4.
7. A computer readable storage medium storing computer instructions which, when executed by a processor, perform the steps of the method of any of claims 1-4.
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| CN113109668B (en) * | 2021-04-12 | 2022-12-20 | 国网陕西省电力公司西安供电公司 | Asymmetric fault location method for distribution network based on zero-mode traveling wave mutation of reclosing |
| CN115356588B (en) * | 2022-08-16 | 2023-12-22 | 国网江苏省电力有限公司南通供电分公司 | GIL fault transient ground potential rising waveform characteristic moment extraction method, system and medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105353268A (en) * | 2015-10-10 | 2016-02-24 | 电子科技大学 | Method for judging and positioning distributed traveling wave fault of power transmission line |
| CN109738763A (en) * | 2019-02-28 | 2019-05-10 | 国网湖北省电力有限公司黄石供电公司 | A method for locating short-circuit faults in medium-voltage distribution cables based on wavelet packet transform |
| CN110095691A (en) * | 2019-02-01 | 2019-08-06 | 长沙理工大学 | Initial wavefront extracting method and device based on Full wave shape principal frequency component |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102944818B (en) * | 2012-11-27 | 2015-06-24 | 广东电网公司佛山供电局 | Geographic information system (GIS) terminal cable fault on-line location method |
| CN105261202B (en) * | 2015-11-05 | 2019-03-19 | 江苏省电力公司电力科学研究院 | Transmission delay measurement method based on B-spline interpolating wavelet Singularity detection |
| CN109061390B (en) * | 2018-09-07 | 2023-12-15 | 中电普瑞电力工程有限公司 | Regional traveling wave fault positioning method and system |
| CN110927510B (en) * | 2019-10-17 | 2021-10-01 | 东北大学 | A frequency domain method for double-ended traveling wave fault location of transmission lines |
| CN110967717A (en) * | 2019-12-23 | 2020-04-07 | 合肥工业大学 | Cycle slip detection and restoration method based on wavelet transform method |
-
2020
- 2020-10-26 CN CN202011155187.4A patent/CN112415328B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105353268A (en) * | 2015-10-10 | 2016-02-24 | 电子科技大学 | Method for judging and positioning distributed traveling wave fault of power transmission line |
| CN110095691A (en) * | 2019-02-01 | 2019-08-06 | 长沙理工大学 | Initial wavefront extracting method and device based on Full wave shape principal frequency component |
| CN109738763A (en) * | 2019-02-28 | 2019-05-10 | 国网湖北省电力有限公司黄石供电公司 | A method for locating short-circuit faults in medium-voltage distribution cables based on wavelet packet transform |
Non-Patent Citations (1)
| Title |
|---|
| 基于小波变换的高压电缆故障行波测距研究;宋建;硕士电子期刊(第03期);第1-89页 * |
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