A wind farm line fault location method, device and electronic equipment
By acquiring transient zero-sequence voltage signals at the bus end and collector line end in the wind farm, performing variational mode decomposition and time-frequency transformation, and constructing a line selection matrix, the problem of high cost of wind farm line fault location is solved, and efficient fault location is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHENYANG UNIVERSITY OF TECHNOLOGY
- Filing Date
- 2023-06-13
- Publication Date
- 2026-06-26
AI Technical Summary
Fault location in wind farm lines is costly. Traditional methods require a large number of traveling wave recorders in multi-branch, short-distance transmission lines, which increases costs.
By acquiring transient zero-sequence voltage signal data from the bus end and the end of the collector line, variational mode decomposition and time-frequency transformation are performed to construct a collector line branch selection matrix. Fault location is then performed using a small number of traveling wave recorders, including line selection processing and fault location calculation.
This technology enables fault location in wind farms with a smaller number of traveling wave recorders, reducing the cost of fault location.
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Figure CN116577610B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wind farm fault location technology, and in particular to a method, device, and electronic equipment for locating line faults in wind farms. Background Technology
[0002] Wind energy reserves are abundant and it is a rapidly developing renewable energy source. However, a wind farm is a multi-branch transmission system with a complex topology, short transmission lines, and harsh operating environment. These harsh operating conditions lead to frequent transmission line faults, reducing wind power generation and limiting the development and utilization of wind energy. Traditional traveling wave (TW) fault location methods can be divided into single-ended and double-ended methods, commonly used for long-distance transmission lines in distribution networks. These methods require the installation of specialized TW recorders at one or both ends of each transmission line segment, with the number of recorders generally proportional to the number of branches. When these methods are applied to wind farm collector lines, the dramatic increase in the number of branches due to their multi-branch, short-distance structure directly leads to a greater number of recorders, severely impacting the basic cost of fault location. Summary of the Invention
[0003] In view of this, the present invention provides a method, device and electronic equipment for locating faults in wind farm lines, the main purpose of which is to solve the problem of high cost of locating faults in wind farm lines.
[0004] To address the above problems, this application provides a method for locating line faults in wind farms, comprising:
[0005] Acquire the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm.
[0006] Based on the transient zero-sequence voltage signal datasets, the collector line selection process is performed to obtain the target collector line where the fault has occurred.
[0007] Based on the estimated distance from the predicted fault point of each branch of the target collector line to the intersection of the collector line, a branch selection matrix for the collector line is constructed.
[0008] Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the collector line branch selection matrix is used for line selection processing to obtain the target branch of the target collector line where the fault occurred, so as to obtain the target fault location of the target branch.
[0009] Optionally, the step of performing collector line selection processing based on each of the transient zero-sequence voltage signal datasets to obtain the target collector line where the fault has occurred specifically includes:
[0010] Variational mode decomposition is performed on each of the transient zero-sequence voltage signal datasets to obtain noise-removed voltage component datasets.
[0011] Each component voltage dataset is processed using a preset time-frequency transformation method to obtain a time-frequency matrix corresponding to each component voltage dataset;
[0012] The modulus of each of the time-frequency matrices is calculated to obtain the energy matrix corresponding to each of the time-frequency matrices;
[0013] Based on the energy matrices and the preset collector line selection matrix, the target collector line where the fault occurred is obtained through line selection processing.
[0014] Optionally, the process of selecting the target power collection line based on each of the energy matrices and a preset power collection line selection matrix to obtain the faulty target power collection line specifically includes:
[0015] Calculate the similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to each collector line to obtain the similarity scores.
[0016] Based on the aforementioned similarities and the preset collector line selection matrix, a line selection process is performed to determine the collector line corresponding to the maximum similarity value as the target collector line.
[0017] Optionally, the transient zero-sequence voltage signal dataset based on the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line are processed using the collector line branch selection matrix to obtain the target branch of the target collector line where the fault has occurred, so as to obtain the target fault location of the target branch, specifically including:
[0018] Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the first initial traveling wave signal transmitted from the fault traveling wave to the bus end and the second initial traveling wave signal transmitted from the fault traveling wave to the end of the target collector line are determined.
[0019] Based on the first initial traveling wave signal and the second initial traveling wave signal, the fault distance value corresponding to each estimated distance in the collector line branch selection matrix when a fault occurs is calculated.
[0020] Based on the fault distance values and the length of each predetermined branch, the fault location is performed to obtain the target branch of the target collector line where the fault occurred.
[0021] Optionally, the determination of the first initial traveling wave signal transmitted from the fault traveling wave to the bus end and the second initial traveling wave signal transmitted from the fault traveling wave to the target collector line end, based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the target collector line end, specifically includes:
[0022] Obtain the first time-frequency matrix corresponding to the first component voltage dataset of the transient zero-sequence voltage signal dataset at the bus end, and the second time-frequency matrix corresponding to the second voltage dataset of the transient zero-sequence voltage signal dataset at the end of the target collector line;
[0023] Peak values are calculated for each frequency component in the first time-frequency matrix and the second time-frequency matrix respectively, to obtain each first peak value corresponding to the first time-frequency matrix and each second peak value corresponding to the second time-frequency matrix.
[0024] The frequency component voltage signal in the first time-frequency matrix corresponding to the largest peak value in the first peak value is determined as the first initial traveling wave signal;
[0025] The frequency component voltage signal in the second time-frequency matrix corresponding to the largest peak value in the second peak value is determined as the second initial traveling wave signal.
[0026] Optionally, the step of calculating the fault distance value corresponding to each estimated distance where a fault occurs based on the first initial traveling wave signal and the second initial traveling wave signal specifically includes:
[0027] The wavefront of the first initial traveling wave signal is calibrated to determine the first moment when the fault traveling wave is transmitted to the bus end;
[0028] The wavefront of the second initial traveling wave signal is calibrated to determine the second moment when the fault traveling wave reaches the end of the target collector line;
[0029] Based on the first time point, the second time point, the initial time of the fault occurrence, and the predetermined topology, the fault distance value corresponding to each estimated distance of the fault occurrence is calculated.
[0030] Optionally, the step of locating the target fault location based on each fault distance value and each predetermined branch length specifically includes:
[0031] Determine whether the fault distance value and the predetermined branch length of each branch meet the preset conditions, and take the branch that meets the preset conditions as the target branch of the target collector line where the fault occurred.
[0032] The target location of the fault is calculated based on the fault distance value corresponding to the target branch.
[0033] Optionally, if the estimated distance value and branch length corresponding to each branch do not meet the preset conditions, the double-ended traveling wave method is used to locate the fault in the target collector line to obtain the fault location result.
[0034] To address the aforementioned problems, this application provides a wind farm line fault location device, comprising:
[0035] Acquisition module: used to acquire the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm.
[0036] The collector line selection module is used to perform collector line selection processing based on the transient zero-sequence voltage signal datasets to obtain the target collector line where the fault has occurred.
[0037] Construction module: Used to construct the branch selection matrix of the target collector line based on the estimated distance from the predicted fault point of each branch to the intersection of the collector line.
[0038] The collector line branch selection module is used to perform branch selection processing based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, using the collector line branch selection matrix to obtain the target branch of the target collector line where the fault has occurred, so as to obtain the target fault location of the target branch.
[0039] To solve the above problems, this application provides an electronic device, characterized in that it includes at least a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the wind farm line fault location method described above when executing the computer program in the memory.
[0040] This application records traveling wave data at the bus end and the ends of each collector line branch, and uses the transient zero-sequence voltage signal dataset from the bus end and the ends of each collector line to perform collector line selection processing to obtain the target collector line where the fault has occurred. Then, by constructing a collector line branch selection matrix, the target branch of the target collector line where the fault has occurred is obtained through the collection line branch selection matrix. This application can achieve fault location of wind farms with fewer traveling wave recorders, saving the cost of wind farm fault location.
[0041] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description
[0042] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0043] Figure 1 A flowchart illustrating a method for locating line faults in a wind farm, as provided in an embodiment of this application, is shown.
[0044] Figure 2 A flowchart illustrating a wind farm line fault location method according to another embodiment of this application is shown;
[0045] Figure 3 This paper shows a structural block diagram of a wind farm line fault location device according to another embodiment of the present application;
[0046] Figure 4 A schematic diagram of the wind farm collection line in this application is shown. Detailed Implementation
[0047] Various embodiments and features of this application are described herein with reference to the accompanying drawings.
[0048] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this application will be apparent to those skilled in the art.
[0049] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.
[0050] These and other features of this application will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.
[0051] It should also be understood that although this application has been described with reference to some specific examples, those skilled in the art can certainly implement many other equivalent forms of this application.
[0052] The above and other aspects, features and advantages of this application will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.
[0053] Specific embodiments of this application are described thereafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of this application, which can be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure the application. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely serve as the basis and representative basis for the claims to teach those skilled in the art to use this application in a variety of substantially any suitable detailed structures.
[0054] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in other embodiments,” all of which may refer to one or more of the same or different embodiments according to this application.
[0055] This application provides a method for locating faults in wind farm lines, such as... Figure 1 As shown, it includes:
[0056] Step S101: Obtain the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm.
[0057] In the specific implementation process of this step, the wind farm collection lines have many branches and many types of faults. In order to accurately locate the faulty branch of the wind farm collection line, the preset time can be a time interval such as 0.001S or 0.0001S. This application does not limit the preset time. The end of each collection line refers to the transient zero-sequence voltage signal dataset corresponding to the end of the terminal branch of each collection line.
[0058] Step S102: Perform line selection processing on the collector line based on the transient zero-sequence voltage signal datasets to obtain the target collector line where the fault has occurred;
[0059] In this step, variational mode decomposition (VMD) is performed on each transient zero-sequence voltage signal dataset to obtain noise-removed component voltage datasets. The VMD method is used to remove noise and obtain the IMF1 component, resulting in the component voltage datasets. A preset time-frequency transformation method is applied to each component voltage dataset to obtain a time-frequency matrix corresponding to each component voltage dataset. This preset time-frequency transformation method can be the Stockwell transform method. Modulus calculation is performed on each time-frequency matrix to obtain the corresponding energy matrix. Based on the energy matrix and a preset collector line selection matrix, line selection is performed to obtain the target collector line where the fault has occurred.
[0060] Step S103: Based on the estimated distance from the predicted fault point of each branch of the target collector line to the intersection of the collector line along the branch, construct the collector line branch selection matrix;
[0061] In the specific implementation process of this step, when constructing the target collector line, the predetermined topology of the target collector line can be determined. The length of each branch and the distance from the intersection of each branch with the target collector line to the bus can be read according to the predetermined topology. Based on the code of each branch and the estimated distance from the fault point along the branch to the intersection of the collector line, a collector line branch selection matrix is constructed. This lays the foundation for subsequent line selection processing based on the collector line branch selection matrix to obtain the target branch of the target collector line where the fault occurred.
[0062] Step S104: Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the collector line branch selection matrix is used to perform line selection processing to obtain the target branch of the target collector line where the fault occurred, so as to obtain the target fault location of the target branch.
[0063] In this step, based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the first initial traveling wave signal transmitted from the fault traveling wave to the bus end and the second initial traveling wave signal transmitted from the fault traveling wave to the end of the target collector line are determined. Based on the first initial traveling wave signal and the second initial traveling wave signal, the fault distance value corresponding to each estimated distance in the collector line branch selection matrix at the time of the fault is calculated. Based on each fault distance value and each predetermined branch length, the fault is located to obtain the target branch of the target collector line where the fault occurred.
[0064] This application records traveling wave data at the bus end and the ends of each collector line branch, and uses the transient zero-sequence voltage signal dataset from the bus end and the ends of each collector line to perform collector line selection processing to obtain the target collector line where the fault has occurred. Then, by constructing a collector line branch selection matrix, the target branch of the target collector line where the fault has occurred is obtained through the collection line branch selection matrix. This application can achieve fault location of wind farms with fewer traveling wave recorders, saving the cost of wind farm fault location.
[0065] Another embodiment of this application provides a different method for locating line faults in wind farms, such as... Figure 2 As shown, it includes:
[0066] Step S201: Obtain the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm.
[0067] In the specific implementation process of this step, the wind farm's collector lines are characterized by numerous branches and various fault types. In order to accurately locate the faulty branch of the wind farm's collector lines, the preset duration can be a time interval such as 0.001ms or 0.0001ms. The preset duration in this application is determined based on the sampling frequency of the traveling wave, which can be 5MHz, 10MHz, 6.4MHz, etc. The preset duration can be determined by the sampling frequency. The preset duration can be selected as half of the sampling frequency period. This application does not impose any restrictions on the preset duration and can apply traveling wave sampling equipment with any sampling frequency. The term "end of each collector line" in this application refers to the end of each collector line terminal branch.
[0068] Step S202: Perform variational mode decomposition on each of the transient zero-sequence voltage signal datasets to obtain the voltage datasets of each component after noise removal;
[0069] In this step, variational mode decomposition (VMD) is performed on the zero-sequence voltage signals at all acquisition points. The IMF1 component of the VMD is extracted to eliminate the influence of measurement noise on the original signal, resulting in a noise-removed dataset of voltage components. The VMD method can be used, which is suitable for nonlinear time-series signals. It primarily utilizes the idea of solving variational problems to extract signals, decomposing an original signal into multiple signals with different center frequencies (i.e., not within the same modulation signal) without losing the original signal characteristics.
[0070] Step S203: Process each component voltage dataset using a preset time-frequency transformation method to obtain a time-frequency matrix corresponding to each component voltage dataset;
[0071] In the specific implementation process of this step, the preset time-frequency transformation method can be the Stockwell transformation method. The preset time-frequency transformation method is used to process each component voltage dataset to obtain the mathematical formula for calculating the time-frequency matrix corresponding to each component voltage dataset as shown in the following formula (1):
[0072]
[0073] Where V1 is an arbitrary component voltage; n, k, q = 0, 1, 2, ..., N-1; N is the number of fault voltage values, determined by the sampling frequency; and T is the sampling frequency. This method can be used to analyze fault data while taking into account both the time and frequency domain characteristics of the fault signal.
[0074] Step S204: Perform modulus calculation on each of the time-frequency matrices to obtain the energy matrix corresponding to each of the time-frequency matrices;
[0075] In the specific implementation process of this step, the modulus calculation is performed on each of the time-frequency matrices, and the mathematical formula for calculating the energy matrix corresponding to each of the time-frequency matrices is as follows (2):
[0076] E m×n =|S m×n | 2 (2)
[0077] Where m and n are the number of frequencies in the frequency domain analysis and the time domain analysis, respectively.
[0078] Step S205: Calculate the similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to each collector line to obtain the similarity scores;
[0079] In the specific implementation process of this step, the mathematical formula for calculating the similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to each collector line is as follows (3):
[0080]
[0081] Where i, j = 0, 1, 2, ..., N; N is the number of collector lines in the wind farm; E Mi and E Mj The sampling points are M and M respectively. i and M j The calculated energy matrix is given by r, which represents the number of rows and c, which represents the number of columns.
[0082] The similarity calculated using the above formula is: The similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to the end of the first collector line terminal branch; The similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to the end of the second collector line terminal branch; This represents the similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to the end of the terminal branch of the nth collector line.
[0083] Step S206: Based on the similarity scores and the preset collection line selection matrix, perform line selection processing to determine the collection line corresponding to the maximum similarity score as the target collection line;
[0084] In the specific implementation process of this step, the preset collector line selection matrix is as shown in the following formula (4):
[0085]
[0086] Substituting the calculated similarity values into formula (4) above, the collector line corresponding to the maximum similarity value among the various similarity values is determined as the target collector line. In the collector line selection matrix, the lower the similarity in the fault, the larger the similarity coefficient, and the corresponding column number is the faulty collector line number; conversely, the higher the fault similarity, the smaller the similarity coefficient, and the corresponding column number is not faulty. Therefore, fault area rules can be established by judging the predetermined characteristics of elements within the ADM, where the column number containing the maximum similarity value is the final faulty collector line determination result.
[0087] Step S207: Based on the estimated distance from the predicted fault point of each branch of the target collector line to the intersection of the collector line along the branch, construct the collector line branch selection matrix;
[0088] In the specific implementation process of this step, based on the estimated distance from the predicted fault point of each branch of the target collector line to the intersection of the collector line along the branch, the resulting collector line branch selection matrix can be represented by the following formula (5):
[0089]
[0090] in To predict the distance from fault point F to branch and collector line node N k-1 The estimated distance; N n W n Number the branch paths.
[0091] Step S208: Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, determine the first initial traveling wave signal transmitted from the fault traveling wave to the bus end and the second initial traveling wave signal transmitted from the fault traveling wave to the end of the target collector line.
[0092] In this step, the first time-frequency matrix corresponding to the first component voltage dataset of the transient zero-sequence voltage signal dataset at the bus end and the second time-frequency matrix corresponding to the second voltage dataset of the transient zero-sequence voltage signal dataset at the end of the target collector line are obtained. Specifically, the first time-frequency matrix corresponding to the first component voltage dataset of the transient zero-sequence voltage signal dataset at the bus end and the second time-frequency matrix corresponding to the second voltage dataset of the transient zero-sequence voltage signal dataset at the end of the target collector line, calculated in step S203, are obtained. Peak values are calculated for each frequency component in the first and second time-frequency matrices to obtain each first peak value corresponding to the first time-frequency matrix and each second peak value corresponding to the second time-frequency matrix. The frequency component voltage signal in the first time-frequency matrix corresponding to the largest peak value among the first peak values is determined as the first initial traveling wave signal; the frequency component voltage signal in the second time-frequency matrix corresponding to the largest peak value among the second peak values is determined as the second initial traveling wave signal.
[0093] Step S209: Based on the first initial traveling wave signal and the second initial traveling wave signal, calculate the fault distance value corresponding to each estimated distance in the collector line branch selection matrix when a fault occurs;
[0094] In the specific implementation process of this step, the wavefront of the first initial traveling wave signal is calibrated to determine the first moment when the fault traveling wave is transmitted to the bus end.
[0095] The wavefront of the second initial traveling wave signal is calibrated to determine the second moment when the fault traveling wave reaches the end of the target collector line.
[0096] Based on the first moment Second moment The initial time t when the fault occurs f And a predetermined topology, calculate the fault distance value corresponding to each estimated distance where a fault occurs; the calculation formula for the fault distance value is as shown in the following formula (6):
[0097]
[0098] in, and It is the distance from F to the two ends of W0 and Wn; and It is the distance from the nearest node Np at F to the two endpoints W0 and Wn; and The length is determined based on the known structure; and It is the time t takes for the fault traveling wave to reach W0 and Wn.f It is the initial time of the line fault, v tw It is the propagation speed of the fault traveling wave.
[0099] The derivation of formula (6) is as follows: In a tree-like radial wind farm, any collector line is a typical multi-branch structure, including one collector line and multiple branch lines. A schematic diagram of a simple structure is shown below. Figure 4 As shown: When point F is the fault point, the fault traveling wave will travel from the fault point (F) along the transmission line to the ends of the line (W0 and Wn). Measurement points are set at both ends of the collection line (M0 and Mn). When the fault occurs on any branch, the following mathematical expressions (7), (8), (9), and (10) are always satisfied:
[0100]
[0101]
[0102]
[0103]
[0104] According to Formula 10, the expression for the propagation speed of the fault traveling wave can be obtained as shown in Formula (11):
[0105]
[0106] According to formula (11), equations (8) and (9) can be transformed to obtain formulas (12) and (13):
[0107]
[0108]
[0109] Based on equations (10), (12), and (13), we can derive the formula (6) for calculating the fault distance value:
[0110]
[0111] Step S210: Determine whether the fault distance value and the predetermined branch length corresponding to each branch meet the preset conditions, and take the branch that meets the preset conditions as the target branch of the target collector line where the fault occurs.
[0112] In the specific implementation of this step, the preset conditions are as shown in the following formula (14):
[0113]
[0114] If a fault occurs on a branch of the collector line, then there must be a prediction. If the conditions of formula (14) are met, the branch that meets the preset conditions will be used as the target branch of the target collector line that has a fault.
[0115] Step S211: Calculate the target location of the fault based on the fault distance value corresponding to the target branch;
[0116] In the specific implementation process of this step, the fault distance value corresponding to the target branch is used as the basis. The mathematical formula for calculating the target location of the fault is shown in the following formula (15):
[0117]
[0118]
[0119] By fault distance value The distance from the intersection of the target branch and the target collector line to the bus terminal in the predetermined topology. And the distance from the intersection of the target branch and the target collector line in the predetermined topology to the end of the target collector line. The fault distance from the fault location to the bus end or the fault distance from the fault location to the end of the collector line is calculated.
[0120] Step S212: When the estimated distance value and branch length corresponding to each branch do not meet the preset conditions, the double-ended traveling wave method is used to locate the fault in the target collector line and obtain the fault location result.
[0121] In the specific implementation of this step, if the estimated distance value and branch length corresponding to each branch do not meet the preset conditions, then the current fault location is not on any branch of the collector line. It can be determined that the location of the fault is on the trunk of the target collector line. Then, the fault location is obtained by using the traditional double-end traveling wave method to obtain the fault distance value from the location of the fault to the bus end or the end of the target collector line.
[0122] This application utilizes traveling wave recording at the bus end and the ends of each collector line's terminal branches. By acquiring a dataset of transient zero-sequence voltage signals at the bus end and the ends of each collector line within a preset time range after a line fault occurs in the wind farm, a pre-constructed collector line selection matrix is used to select the target collector line where the fault occurred. Then, by constructing a collector line branch selection matrix, the target branch where the fault occurred and the specific location of the fault are determined. When the fault location is not on any branch, it can be determined that the fault location is on the main branch of the target collector line. The traditional double-ended traveling wave method is then used for fault location to obtain the fault distance value from the fault location to the bus end or the end of the target collector line. This application can complete the collector line selection and target collector line branch identification for complex topologies of tree-like radial wind farms with fewer traveling wave recorders, thus saving fault location costs.
[0123] Another embodiment of this application provides a wind farm line fault location device, such as... Figure 3 As shown, it includes:
[0124] Acquisition Module 1: Used to acquire the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm.
[0125] Collection line selection module 2: used to perform collection line selection processing based on the transient zero-sequence voltage signal datasets to obtain the target collection line where the fault has occurred;
[0126] Module 3: Used to construct a branch selection matrix for the target collector line based on the estimated distance from the predicted fault point of each branch to the intersection of the collector line.
[0127] The collector line branch selection module 4 is used to perform line selection processing based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line using the collector line branch selection matrix, so as to obtain the target branch of the target collector line where the fault has occurred, and thus obtain the target fault location of the target branch.
[0128] In specific implementation, the collector line selection module 2 is specifically used for: performing variational mode decomposition on each of the transient zero-sequence voltage signal datasets to obtain noise-removed component voltage datasets; processing each of the component voltage datasets using a preset time-frequency transformation method to obtain a time-frequency matrix corresponding to each of the component voltage datasets; performing modulus calculation on each of the time-frequency matrices to obtain an energy matrix corresponding to each of the time-frequency matrices; and performing line selection processing based on each of the energy matrices and the preset collector line selection matrix to obtain the target collector line where the fault has occurred.
[0129] In the specific implementation process, the power collection line selection module 2 is also used to calculate the similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to each power collection line, so as to obtain each similarity; based on each similarity and the preset power collection line selection matrix, the line selection process is performed to determine the power collection line corresponding to the maximum similarity as the target power collection line.
[0130] In specific implementation, the collector line branch selection module 4 is specifically used to: determine the first initial traveling wave signal transmitted from the fault traveling wave to the bus end and the second initial traveling wave signal transmitted from the fault traveling wave to the end of the target collector line based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line; calculate the fault distance value corresponding to each estimated distance in the collector line branch selection matrix when the fault occurs based on the first initial traveling wave signal and the second initial traveling wave signal; and perform fault location based on each fault distance value and each predetermined branch length to obtain the target branch of the target collector line where the fault occurred.
[0131] In the specific implementation process, the collector line branch selection module 4 is also used to: obtain the first time-frequency matrix corresponding to the first component voltage dataset of the transient zero-sequence voltage signal dataset at the bus end, and the second time-frequency matrix corresponding to the second voltage dataset of the transient zero-sequence voltage signal dataset at the end of the target collector line; perform peak calculation on each frequency component in the first time-frequency matrix and the second time-frequency matrix respectively to obtain each first peak value corresponding to the first time-frequency matrix and each second peak value corresponding to the second time-frequency matrix; determine the frequency component voltage signal in the first time-frequency matrix corresponding to the largest peak value among the first peak values as the first initial traveling wave signal; and determine the frequency component voltage signal in the second time-frequency matrix corresponding to the largest peak value among the second peak values as the second initial traveling wave signal.
[0132] In the specific implementation process, the collector line branch selection module 4 is also used to: calibrate the wavefront of the first initial traveling wave signal to determine the first moment when the fault traveling wave is transmitted to the bus end; calibrate the wavefront of the second initial traveling wave signal to determine the second moment when the fault traveling wave is transmitted to the end of the target collector line; and calculate the fault distance value corresponding to each estimated distance of the fault based on the first moment, the second moment, the initial moment of the fault, and the predetermined topology.
[0133] In the specific implementation process, the power collection line branch selection module 4 is also used to: determine whether the fault distance value and the predetermined branch length corresponding to each branch meet the preset conditions, and take the branch that meets the preset conditions as the target branch of the target power collection line where the fault occurs; and calculate the target location of the fault based on the fault distance value corresponding to the target branch.
[0134] In the specific implementation process, the power collection line branch selection module 4 is also used to: when the estimated distance value and branch length corresponding to each branch do not meet the preset conditions, use the double-ended traveling wave method to locate the fault in the target power collection line and obtain the fault location result.
[0135] This application records traveling wave data at the bus end and the ends of each collector line branch, and uses the transient zero-sequence voltage signal dataset from the bus end and the ends of each collector line to perform collector line selection processing to obtain the target collector line where the fault has occurred. Then, by constructing a collector line branch selection matrix, the target branch of the target collector line where the fault has occurred is obtained through the collection line branch selection matrix. This application can achieve fault location of wind farms with fewer traveling wave recorders, saving the cost of wind farm fault location.
[0136] Another embodiment of this application provides an electronic device, which can be a server. The electronic device includes a processor, a memory, a network interface, and a database connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile and / or volatile storage media and internal memory. The non-volatile storage media stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The network interface is used to communicate with external clients via a network connection. When the program is executed by the processor, it implements the functions or steps of a wind farm line fault location method on the server side.
[0137] In one embodiment, an electronic device is provided, which can be a client. The electronic device includes a processor, memory, a network interface, a display screen, and an input device connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with an external server via a network connection. When the program of the electronic device is executed by the processor, it implements the functions or steps of a wind farm line fault location method on the client side.
[0138] Another embodiment of this application provides an electronic device, including at least a memory and a processor. The memory stores a computer program, and the processor, when executing the computer program in the memory, performs the following method steps:
[0139] Step 1: Obtain the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm.
[0140] Step 2: Based on the transient zero-sequence voltage signal datasets, perform collector line selection processing to obtain the target collector line where the fault has occurred;
[0141] Step 3: Based on the estimated distance from the predicted fault point of each branch of the target collector line to the intersection of the collector line, construct the collector line branch selection matrix.
[0142] Step 4: Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the collector line branch selection matrix is used to perform line selection processing to obtain the target branch of the target collector line where the fault occurred, so as to obtain the target fault location of the target branch.
[0143] The specific implementation process of the above method steps can be found in the embodiment of the above arbitrary wind farm line fault location method, which will not be repeated here.
[0144] This application records traveling wave data at the bus end and the ends of each collector line branch, and uses the transient zero-sequence voltage signal dataset from the bus end and the ends of each collector line to perform collector line selection processing to obtain the target collector line where the fault has occurred. Then, by constructing a collector line branch selection matrix, the target branch of the target collector line where the fault has occurred is obtained through the collection line branch selection matrix. This application can achieve fault location of wind farms with fewer traveling wave recorders, saving the cost of wind farm fault location.
[0145] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.
Claims
1. A method for locating line faults in a wind farm, characterized in that, include: Acquire the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm. Based on the transient zero-sequence voltage signal datasets, the collector line selection process is performed to obtain the target collector line where the fault has occurred. Based on the estimated distance from the predicted fault point of each branch of the target collector line to the intersection of the collector line, a branch selection matrix for the collector line is constructed. Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the collector line branch selection matrix is used for line selection processing to obtain the target branch of the target collector line where the fault occurred, so as to obtain the target fault location of the target branch. The step of performing line selection processing based on each of the transient zero-sequence voltage signal datasets to obtain the target line where the fault has occurred specifically includes: Variational mode decomposition is performed on each of the transient zero-sequence voltage signal datasets to obtain noise-removed voltage component datasets. Each component voltage dataset is processed using a preset time-frequency transformation method to obtain a time-frequency matrix corresponding to each component voltage dataset; The modulus of each of the time-frequency matrices is calculated to obtain the energy matrix corresponding to each of the time-frequency matrices; The mathematical formulas for calculating each of the energy matrices are shown below: Where: m and n are the number of frequencies in the frequency domain analysis and the time domain analysis, respectively; Based on the energy matrices and the preset collector line selection matrix, the target collector line where the fault occurred is obtained through line selection processing. The transient zero-sequence voltage signal dataset based on the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line are processed using the collector line branch selection matrix to obtain the target branch of the target collector line where the fault has occurred, so as to obtain the target fault location of the target branch, specifically including: Based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, the first initial traveling wave signal transmitted from the fault traveling wave to the bus end and the second initial traveling wave signal transmitted from the fault traveling wave to the end of the target collector line are determined. Based on the first initial traveling wave signal and the second initial traveling wave signal, the fault distance value corresponding to each estimated distance in the collector line branch selection matrix when a fault occurs is calculated. Based on the fault distance values and the length of each predetermined branch, the fault location is performed to obtain the target branch of the target collector line where the fault occurred.
2. The method as described in claim 1, characterized in that, The process of selecting the target power collection line based on the energy matrices and the preset power collection line selection matrix to obtain the faulty target power collection line specifically includes: Calculate the similarity between the energy matrix corresponding to the bus end and the energy matrix corresponding to each collector line to obtain the similarity scores. Based on the aforementioned similarities and the preset collector line selection matrix, a line selection process is performed to determine the collector line corresponding to the maximum similarity value as the target collector line.
3. The method as described in claim 1, characterized in that, The transient zero-sequence voltage signal dataset based on the bus-end transient zero-sequence voltage signal dataset and the target collector line end transient zero-sequence voltage signal dataset determines the first initial traveling wave signal of the fault traveling wave transmitted to the bus-end and the second initial traveling wave signal of the fault traveling wave transmitted to the target collector line end, specifically including: Obtain the first time-frequency matrix corresponding to the first component voltage dataset of the transient zero-sequence voltage signal dataset at the bus end, and the second time-frequency matrix corresponding to the second voltage dataset of the transient zero-sequence voltage signal dataset at the end of the target collector line; Peak values are calculated for each frequency component in the first time-frequency matrix and the second time-frequency matrix respectively, to obtain each first peak value corresponding to the first time-frequency matrix and each second peak value corresponding to the second time-frequency matrix. The frequency component voltage signal in the first time-frequency matrix corresponding to the largest peak value in the first peak value is determined as the first initial traveling wave signal; The frequency component voltage signal in the second time-frequency matrix corresponding to the largest peak value in the second peak value is determined as the second initial traveling wave signal.
4. The method as described in claim 1, characterized in that, The step of calculating the fault distance value corresponding to each estimated distance where a fault occurs, based on the first initial traveling wave signal and the second initial traveling wave signal, specifically includes: The wavefront of the first initial traveling wave signal is calibrated to determine the first moment when the fault traveling wave is transmitted to the bus end; The wavefront of the second initial traveling wave signal is calibrated to determine the second moment when the fault traveling wave reaches the end of the target collector line; Based on the first time point, the second time point, the initial time of the fault occurrence, and the predetermined topology, the fault distance value corresponding to each estimated distance of the fault occurrence is calculated.
5. The method as described in claim 1, characterized in that, The process of locating the target fault location based on each fault distance value and each predetermined branch length specifically includes: Determine whether the fault distance value and the predetermined branch length of each branch meet the preset conditions, and take the branch that meets the preset conditions as the target branch of the target collector line where the fault occurred. The target location of the fault is calculated based on the fault distance value corresponding to the target branch.
6. The method as described in claim 5, characterized in that, When the estimated distance value and branch length corresponding to each branch do not meet the preset conditions, the double-ended traveling wave method is used to locate the fault in the target collector line and obtain the fault location result.
7. A wind farm line fault location device, used to implement any one of the wind farm line fault location methods as described in claims 1 to 6, characterized in that, include: Acquisition module: used to acquire the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of each collector line within a preset time range after a line fault occurs in the wind farm. The collector line selection module is used to perform collector line selection processing based on the transient zero-sequence voltage signal datasets to obtain the target collector line where the fault has occurred. Construction module: Used to construct the branch selection matrix of the target collector line based on the estimated distance from the predicted fault point of each branch to the intersection of the collector line. The collector line branch selection module is used to perform branch selection processing based on the transient zero-sequence voltage signal dataset at the bus end and the transient zero-sequence voltage signal dataset at the end of the target collector line, using the collector line branch selection matrix to obtain the target branch of the target collector line where the fault has occurred, so as to obtain the target fault location of the target branch.
8. An electronic device, characterized in that, It includes at least a memory and a processor, wherein the memory stores a computer program, and the processor, when executing the computer program in the memory, implements the steps of the wind farm line fault location method according to any one of claims 1-6.