Distribution network fault positioning method and system

Abstract

The invention discloses a distribution network fault positioning method and system. The method comprises the following steps: installing a traveling wave acquisition device at each end point of a distribution network; obtaining a shortest traveling wave transmission path and a corresponding path distance array and a boundary position array according to the network topology of the distribution network; fault traveling wave current waveforms sent by all traveling wave acquisition devices are obtained, and effective waveforms and effective paths are obtained; wavelet decomposition is carried out on the effective waveform, and double-end distance measurement is carried out on all effective paths in sequence; judging an initial fault section and an initial distance measurement result according to the double-end distance measurement result and the path distance array in sequence; and comprehensively judging a final fault section and a final distance measurement result according to the initial fault section and the initial distance measurement result. By adopting the scheme of the invention, only the traveling wave acquisition devices need to be installed at all endpoints of the distribution network, the intermediate nodes do not need to be installed, the number of the devices is reduced, the fault points are on multiple paths, a correct distance measurement result can be obtained even if the traveling wave acquisition of a certain device fails, and the fault tolerance is high.

Description

Technical Field

[0001] The present invention relates to the field of power system fault location, and in particular to a distribution network fault location method and system. Background Art

[0002] The distance measurement methods in power grids are mainly impedance method and traveling wave method. Impedance method is easily affected by many factors, such as fault point resistance, voltage and current transformer error, distributed capacitance, line structure, attenuated DC component, etc. It is more difficult to apply in distribution networks with complex topology and many branches. Centralized traveling wave distance measurement method has been widely used in the field, and operating experience shows that its distance measurement accuracy is better than impedance method. For distribution networks with complex topology, a distributed traveling wave distance measurement system is required. The system generally consists of three parts: traveling wave current acquisition devices installed on the line, wireless communication network, line selection and distance measurement master station. The acquisition device collects the traveling wave current waveform at the installation location on site and transmits it to the distance measurement master station through the wireless communication network. The distance measurement master station completes the line selection and distance measurement calculation according to the pre-set topological parameters and the received waveform information. The distributed traveling wave distance measurement system needs to install traveling wave acquisition devices at all endpoints and intermediate nodes, which is relatively expensive; if the traveling wave acquisition of a certain acquisition device fails, an incorrect distance measurement result may be obtained. Therefore, a distance measurement method with fewer installation devices and high fault tolerance to traveling wave acquisition failure is required. Summary of the invention

[0003] The purpose of the present invention is to provide a distribution network fault location method and system to solve the defects of the existing distance measurement method, such as high cost and low fault tolerance.

[0004] In order to achieve the above objectives, this application adopts the following technical solutions:

[0005] According to a first aspect of the present application, a distribution network fault location method is proposed, comprising:

[0006] Install a traveling wave acquisition device at each end point of the distribution network;

[0007] According to the distribution network topology, the shortest traveling wave transmission path between N endpoints is obtained, and traveling wave transmission paths and the corresponding path distance array and boundary position array; where N is the total number of endpoints of the distribution network;

[0008] Obtain the fault traveling wave current waveform sent by all traveling wave acquisition devices, and obtain the effective waveform and effective path;

[0009] Perform wavelet decomposition on the effective waveform and perform double-end ranging on all effective paths in turn;

[0010] Determine whether the fault point is located on the valid path according to the double-end distance measurement result of each valid path and the path distance array in turn, and if so, further determine the fault section on the valid path and the distance measurement result from one end of the fault section according to the boundary position array;

[0011] The final fault section and distance measurement result are comprehensively determined based on all fault sections and the distance measurement results at one end of the fault section.

[0012] According to some embodiments, the distribution network is a network with uniform traveling wave speed; for a hybrid network, the network is divided into different distribution networks with connection points as boundaries and fault location is performed separately.

[0013] According to some embodiments, the constituent elements of the path array are the total path length from each endpoint or intermediate node in the path to the starting endpoint, and the first element is 0, indicating that the total path length from the starting endpoint to the starting endpoint is 0; the constituent elements of the boundary position array are the endpoint or intermediate node numbers in the path in sequence.

[0014] According to some embodiments, obtaining a valid waveform and a valid path specifically includes:

[0015] If a certain traveling wave acquisition device acquires data successfully, and the difference between the time stamp of the corresponding fault traveling wave current waveform acquired by the ranging master station and the average time stamp of all fault traveling wave current waveforms does not exceed the limit value, the corresponding fault traveling wave current waveform is determined to be a valid waveform;

[0016] The traveling wave transmission path in which the fault traveling wave current waveforms sent by the traveling wave collection devices at both ends are all valid waveforms is a valid path.

[0017] According to some embodiments, performing wavelet decomposition on the effective waveform and sequentially performing dual-end ranging on all effective paths includes:

[0018] Perform wavelet decomposition on the effective waveform, calibrate the first wave head time, and perform dual-end ranging on all effective paths in turn according to the following formula based on the first wave head time:

[0019]

[0020] Where, d xy is the two-terminal traveling wave ranging result of the shortest path from end point x to end point y, L xy is the length of the shortest path from endpoint x to endpoint y, t x and t y is the first wave head moment corresponding to the fault traveling wave current waveform at endpoints x and y; v is the traveling wave velocity.

[0021] According to some embodiments, the method of determining whether the fault point is located on the valid path according to the dual-end ranging result and the path distance array of each valid path in turn is as follows: comparing the dual-end ranging result with the elements in the path distance array in turn, if the difference between the ranging result and a certain element is less than a first preset deviation threshold, the fault point is not on the valid path, otherwise the fault point is on the valid path;

[0022] The method of further determining the fault section on the valid path and the distance measurement result from one end of the fault section according to the boundary position array is as follows: determining between which two elements of the path distance array the double-end distance measurement result is located, determining the fault section according to the corresponding relationship between the two elements and the boundary position array, and subtracting the smaller of the two elements from the double-end distance measurement result to obtain the distance measurement result from one end of the fault section.

[0023] According to some embodiments, the final fault section is determined comprehensively based on all fault sections and the distance measurement results from one end of the fault section, specifically: all fault sections are counted, and the fault section with the most occurrences is taken as the final fault section;

[0024] The final distance measurement result is calculated according to the distance measurement result of one end of the fault section corresponding to the final fault section.

[0025] According to some embodiments, the final distance measurement result is calculated by: assuming that the number of occurrences of the faulty segment with the largest number of occurrences is sum_valid0, and taking the average value of the distance measurement results corresponding to sum_valid0 at one end of the faulty segment as the final distance measurement result.

[0026] According to some embodiments, the final ranging result calculation method is: let the number of occurrences of the fault section with the largest number of occurrences be sum_valid0, calculate the average value of the ranging results at one end of the distance fault section corresponding to sum_valid0, eliminate the ranging results at one end of the distance fault section whose deviation from the average value exceeds a second preset deviation threshold to obtain a valid ranging result, and calculate the average value of the valid ranging results as the final ranging result.

[0027] According to a second aspect of the present application, a distribution network fault location system is proposed, comprising:

[0028] A traveling wave acquisition device is installed at all endpoints of the distribution network; when a fault occurs, the traveling wave acquisition device collects the fault traveling wave current waveform and sends it to the ranging master station;

[0029] The ranging master station includes a transmission path acquisition unit, a waveform acquisition unit, a dual-end ranging unit, an initial determination unit and a comprehensive determination unit; wherein:

[0030] The transmission path acquisition unit is used to obtain the shortest traveling wave transmission path between two N endpoints according to the distribution network topology, and obtain traveling wave transmission paths and the corresponding path distance array and boundary position array; where N is the total number of endpoints of the distribution network;

[0031] The waveform acquisition unit is used to acquire the fault traveling wave current waveform sent by all traveling wave acquisition devices, and acquire the effective waveform and effective path;

[0032] The dual-end distance measurement unit is used to perform wavelet decomposition on the effective waveform and perform dual-end distance measurement on all effective paths in sequence;

[0033] The initial determination unit is used to determine whether the fault point is located on the valid path according to the double-end distance measurement result of each valid path and the path distance array in turn, and if so, further determine the fault section on the valid path and the distance measurement result of one end of the fault section according to the boundary position array;

[0034] The comprehensive determination unit is used to comprehensively determine the final fault section and the distance measurement result according to all the fault sections and the distance measurement results at one end of the fault section.

[0035] According to a third aspect of the present application, an electronic device is provided, comprising:

[0036] A processor; and a memory storing computer instructions, which, when executed by the processor, causes the processor to execute the aforementioned distribution network fault locating method.

[0037] According to a fourth aspect of the present application, a non-transitory computer storage medium is proposed, characterized in that a computer program is stored therein, and when the computer program is executed by multiple processors, the processors execute the aforementioned distribution network fault locating method.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1) It is only necessary to install the traveling wave acquisition device at all endpoints of the distribution network, and the intermediate nodes do not need to be installed, thus saving the number of devices.

[0040] 2) If the fault point is on multiple paths, even if the traveling wave acquisition of a certain device fails, the correct distance measurement result can be obtained with high fault tolerance, realizing accurate line selection and fault distance measurement for distribution networks with complex topology. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of a distribution network fault locating method provided by an embodiment of the present invention;

[0042] Figure 2It is a topological diagram of a distribution network system of an implementation case of the present invention;

[0043] Figure 3 is a schematic diagram of a distribution network fault location system provided by an embodiment of the present invention;

[0044] Figure 4 A structural diagram of an electronic device provided by the present invention is shown. DETAILED DESCRIPTION

[0045] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0046] like Figure 1 As shown, a schematic diagram of a distribution network fault location method provided by an embodiment of the present invention includes the following steps:

[0047] S100: Install a traveling wave acquisition device at each end point of the distribution network.

[0048] The traveling wave acquisition device only needs to be installed at all endpoints of the distribution network, and does not need to be installed at intermediate nodes, saving the number of devices. The traveling wave acquisition device can collect and send the current traveling wave signal, and send a collection failure signal when the collection fails.

[0049] The distribution network in this application is a network with uniform traveling wave speed. For a hybrid network, the traveling wave speeds in the network are inconsistent, such as a hybrid network of overhead lines and cables, which needs to be divided into different distribution networks with the connection points as the boundaries for fault location.

[0050] S200: According to the distribution network topology, the shortest traveling wave transmission path between N endpoints is obtained. traveling wave transmission paths and the corresponding path distance array and boundary position array; where N is the total number of endpoints of the distribution network.

[0051] According to the distribution network topology, the traveling wave transmission path between N endpoints is obtained. When there is a ring network in the network, resulting in different paths between the two endpoints, the shortest path needs to be selected, and finally the The shortest traveling wave transmission path.

[0052] In some embodiments, the constituent elements of the path array are the total path length from each endpoint or intermediate node in the path to the starting endpoint, and the first element is 0, indicating that the total path length from the starting endpoint to the starting endpoint is 0; the constituent elements of the boundary position array are the endpoint or intermediate node numbers in the path in sequence.

[0053] by Figure 2Take the distribution network topology in as an example. The distribution network in the figure has 6 endpoints, 6 traveling wave acquisition devices are installed, numbered T1~T6, and 4 intersections in the network are numbered B1~B4. Among them, the length of T1B2 segment is a, the length of B2B3 segment is b, the length of B1B2 segment is c, the length of B1T3 segment is d, the length of B1T2 segment is e, the length of B3B4 segment is f, the length of B4T6 segment is g, the length of B3T4 segment is h, and the length of B4T5 segment is i. According to the installation position of the traveling wave acquisition device and the length of each section line, the above rules can be used to form There are 15 path distance arrays and 15 boundary position arrays. The following example illustrates the contents of some path arrays:

[0054] T1T2=[0,a,a+c,a+c+e];

[0055] T1T3=[0,a,a+c,a+c+d];

[0056] T1T4=[0,a,a+b,a+b+h];

[0057] T1T5=[0,a,a+b,a+b+f,a+b+f+i];

[0058] T1T6=[0,a,a+b,a+b+f,a+b+f+g];

[0059] T2T3=[0,e,e+d];

[0060] T2T4=[0,e,e+c,e+c+b,e+c+b+h];

[0061] T2T5=[0,e,e+c,e+c+b,e+c+b+f,e+c+b+f+i];

[0062] T2T6=[0,e,e+c,e+c+b,e+c+b+f,e+c+b+f+g];

[0063] Each path distance array has a corresponding boundary position array LOC (recording the number of each point on the path), for example:

[0064] The boundary position array LOC_1_2 corresponding to the path distance array T1T2 = [T1, B2, B1, T2];

[0065] S300: Acquire the fault traveling wave current waveforms sent by all traveling wave acquisition devices, and acquire the effective waveforms and effective paths.

[0066] The traveling wave acquisition device can collect waveforms and send them to the main station through wireless or optical fiber communication. If the device fails to collect the traveling wave waveform, it will send a collection failure signal to the main station. If the main station does not receive a valid waveform due to communication abnormalities or other reasons, the collection failure signal of the device will also be set. After a device fails to collect, the distance measurement of the path related to the device will be invalid.

[0067] In some embodiments, the acquisition of a valid waveform and a valid path specifically includes: if a certain traveling wave acquisition device acquires successfully, and the difference between the time stamp of the corresponding fault traveling wave current waveform acquired by the ranging master station and the average of the time stamps of all fault traveling wave current waveforms does not exceed a limit value, then the corresponding fault traveling wave current waveform is determined to be a valid waveform. The traveling wave transmission path in which the fault traveling wave current waveforms sent by the traveling wave acquisition devices at both ends are all valid waveforms is a valid path.

[0068] S400: performing wavelet decomposition on the effective waveform, and performing dual-end ranging on all effective paths in sequence.

[0069] In some embodiments, wavelet decomposition is performed on the effective waveform, and dual-end ranging is performed sequentially on all effective paths, including:

[0070] Perform wavelet decomposition on the effective waveform and calibrate the moment of the first wave head.

[0071] According to the first wave head time, dual-end ranging is performed on all valid paths in turn according to the following formula:

[0072]

[0073] Where, d xy is the two-terminal traveling wave ranging result of the shortest path from end point x to end point y, L xy is the length of the shortest path from endpoint x to endpoint y, t x and t y is the first wave head moment corresponding to the fault traveling wave current waveform at endpoints x and y; v is the traveling wave velocity.

[0074] In this application, after wavelet decomposition, only the first wave head needs to be calibrated, and the reflected wave head is not calibrated, so the amount of calculation is small.

[0075] S500: determining whether the fault point is located on the valid path according to the dual-end distance measurement result of each valid path and the path distance array in turn, and if so, further determining the fault section on the valid path and the distance measurement result from one end of the fault section according to the boundary position array.

[0076] In some embodiments, the method for determining whether the fault point is located on the effective path according to the double - end ranging results and the path distance array of each effective path in sequence is as follows: Compare the double - end ranging results with the elements in the path distance array in sequence. If the difference between the ranging result and a certain element is less than the first preset deviation threshold, the fault point is not on this effective path; otherwise, the fault point is located on this effective path. The method for further determining the fault section on the effective path and the ranging result from one end of the fault section according to the boundary position array is as follows: Determine between which two elements of the path distance array the double - end ranging result is located, determine the fault section according to the corresponding relationship between the two elements and the boundary position array, and subtract the smaller of the two elements from the double - end ranging result to obtain the ranging result from one end of the fault section.

[0077] Illustrate the method for determining whether the fault point is on a certain effective path, as well as the method for determining the fault section and the ranging result from one end of the fault section. Denote that the path distance array of the k - th effective path contains n k elements, specifically PATHk = [pk1, pk2, …, pk ( n k) , and the corresponding boundary position array is PATHk_LOC = [Sk1, Sk2, …, Sk(n k )]. If the double - end ranging result of this path is MEAREk, compare MEAREk with the elements in PATHk in sequence. If there exists 1 ≤ j ≤ n k such that ABS(MEAREk - pkj) < △D holds (△D is the first preset deviation threshold), it is considered that the fault point is not on the k - th effective path. If there is no j such that ABS(MEAREk - pkj) < △D holds after traversal, the fault point is located on the k - th effective path. If the fault point is located on the k - th effective path, then further determine the fault section and the ranging result from one end of the fault section: After judgment, pkr < MEAREk < pk(r + 1), that is, the double - end ranging result MEAREk is between pkr and pk(r + 1), then the fault point is located in the section [Skr, Sk(r + 1)], and the distance from Skr is dist_k = MEAREk - pkr.

[0078] S600: Comprehensively determine the final fault section and ranging result based on all the fault sections and the ranging results from one end of the fault section.

[0079] In some embodiments, the method for comprehensively determining the final fault section based on all the fault sections and the ranging results from one end of the fault section is specifically as follows: Count all the fault sections in step S500, and take the fault section with the most occurrences as the final fault section; calculate the final ranging result according to the ranging result from one end of the fault section corresponding to the final fault section.

[0080] In some embodiments, the final distance measurement result is calculated as follows: assuming that the number of occurrences of the faulty segment with the largest number of occurrences is sum_valid0, and taking the average of the distance measurement results corresponding to sum_valid0 at one end of the faulty segment as the final distance measurement result.

[0081] In some embodiments, the final ranging result calculation method is as follows: let the number of occurrences of the fault section with the largest number of occurrences be sum_valid0, calculate the average value of the ranging results at one end of the distance fault section corresponding to sum_valid0, eliminate the ranging results at one end of the distance fault section whose deviation from the average value exceeds a second preset deviation threshold to obtain a valid ranging result, and calculate the average value of all valid ranging results as the final ranging result.

[0082] like Figure 3 The figure shows a distribution network fault location system 700 provided in an embodiment of the present application, including: a traveling wave acquisition device 710 and a ranging master station 720 .

[0083] Traveling wave acquisition device 710 is installed at all endpoints of the distribution network; when a fault occurs, the traveling wave acquisition device collects the fault traveling wave current waveform and sends it to the ranging master station;

[0084] The ranging master station 720 includes a transmission path acquisition unit 721, a waveform acquisition unit 722, a dual-end ranging unit 723, an initial determination unit 724 and a comprehensive determination unit 725; wherein:

[0085] The transmission path acquisition unit 721 is used to obtain the shortest traveling wave transmission path between N endpoints according to the distribution network topology, and obtain traveling wave transmission paths and the corresponding path distance array and boundary position array; where N is the total number of endpoints of the distribution network;

[0086] The waveform acquisition unit 722 is used to acquire the fault traveling wave current waveform sent by all traveling wave acquisition devices, and acquire the effective waveform and effective path;

[0087] The dual-end distance measurement unit 723 is used to perform wavelet decomposition on the effective waveform and perform dual-end distance measurement on all effective paths in sequence;

[0088] The initial determination unit 724 is used to determine whether the fault point is located on the valid path according to the two-end distance measurement result of each valid path and the path distance array in turn, and if so, further determine the fault section on the valid path and the distance measurement result from one end of the fault section according to the boundary position array;

[0089] The comprehensive determination unit 725 is used to comprehensively determine the final fault section and distance measurement result based on all fault sections and distance measurement results at one end of the fault section.

[0090] A distribution network fault location system 700 in the present application performs functions similar to the aforementioned method. For details, please refer to the previous description, which will not be repeated here.

[0091] Figure 4 The structure diagram of an electronic device provided by the present application is shown. It includes a processor and a memory. The memory stores computer instructions. When the computer instructions are executed by the processor, the processor executes the computer instructions to achieve the following. Figure 1 The method and refinement scheme shown.

[0092] It should be understood that the above device embodiments are only illustrative, and the device disclosed in the present invention can also be implemented in other ways. For example, the division of units / modules described in the above embodiments is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units, modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed.

[0093] In addition, unless otherwise specified, each functional unit / module in each embodiment of the present invention may be integrated into one unit / module, each unit / module may exist physically separately, or two or more units / modules may be integrated together. The above-mentioned integrated unit / module may be implemented in the form of hardware or in the form of a software program module.

[0094] If the integrated unit / module is implemented in the form of hardware, the hardware may be a digital circuit, an analog circuit, etc. The physical implementation of the hardware structure includes but is not limited to transistors, memristors, etc. If not otherwise specified, the processor or chip may be any appropriate hardware processor, such as a CPU, a GPU, an FPGA, a DSP, an ASIC, etc. If not otherwise specified, the on-chip cache, the off-chip memory, and the memory may be any appropriate magnetic storage medium or magneto-optical storage medium, such as a resistive random access memory RRAM (Resistive Random Access Memory), a dynamic random access memory DRAM (Dynamic Random Access Memory), a static random access memory SRAM (Static Random-Access Memory), an enhanced dynamic random access memory EDRAM (Enhanced Dynamic Random Access Memory), a high-bandwidth memory HBM (High-Bandwidth Memory), a hybrid memory cube HMC (Hybrid Memory Cube), etc.

[0095] If the integrated unit / module is implemented in the form of a software program module and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a memory and includes several instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present disclosure. The aforementioned memory includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0096] The present application also provides a non-transitory computer storage medium storing a computer program. When the computer program is executed by a plurality of processors, the processors execute the following Figure 1 The method and refinement scheme shown.

[0097] It should be clearly understood that the present application describes how to form and use specific examples, but the present application is not limited to any details of these examples. On the contrary, based on the teaching of the content disclosed in the present application, these principles can be applied to many other embodiments.

[0098] In addition, it should be noted that the above figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, and are not intended to be limiting. It is easy to understand that the processes shown in the above figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0099] The present invention is not limited to the above-mentioned embodiments. The description in the above-mentioned embodiments is only used to help understand the core idea of ​​the present invention. Any modification or equivalent replacement of the present invention based on the idea of ​​the present invention, and any changes made in the specific implementation mode and application scope should fall within the protection scope of the present invention.

Claims

1. A distribution network fault location method, characterized in that: include: Install a traveling wave acquisition device at each end point of the distribution network; According to the distribution network topology, the shortest traveling wave transmission path between N endpoints is obtained, and traveling wave transmission paths and the corresponding path distance array and boundary position array; where N is the total number of endpoints of the distribution network; Obtain the fault traveling wave current waveform sent by all traveling wave acquisition devices, and obtain the effective waveform and effective path; Perform wavelet decomposition on the effective waveform and perform double-end ranging on all effective paths in turn; Determine whether the fault point is located on the valid path according to the double-end distance measurement result of each valid path and the path distance array in turn, and if so, further determine the fault section on the valid path and the distance measurement result from one end of the fault section according to the boundary position array; The final fault section and distance measurement result are comprehensively determined based on all fault sections and the distance measurement results at one end of the fault section.

2. The method according to claim 1, characterized in that: The distribution network is a network with uniform traveling wave speed; for a hybrid network, it is divided into different distribution networks with the connection point as the boundary to perform fault location separately.

3. The method according to claim 1, characterized in that: The constituent elements of the path array are the total length of the path from each endpoint or intermediate node in the path to the head endpoint, and the first element is 0, indicating that the total length of the path from the head endpoint to the head endpoint is 0; The constituent elements of the boundary position array are the endpoints or intermediate node numbers in the path in sequence.

4. The method according to claim 1, characterized in that: The obtaining of the effective waveform and the effective path specifically includes: If a certain traveling wave acquisition device acquires data successfully, and the difference between the time stamp of the corresponding fault traveling wave current waveform acquired by the ranging master station and the average time stamp of all fault traveling wave current waveforms does not exceed the limit value, the corresponding fault traveling wave current waveform is determined to be a valid waveform; The traveling wave transmission path in which the fault traveling wave current waveforms sent by the traveling wave collection devices at both ends are all valid waveforms is a valid path.

5. The method according to claim 1, characterized in that: The wavelet decomposition of the effective waveform and the two-terminal ranging on all effective paths in sequence include: Perform wavelet decomposition on the effective waveform, calibrate the first wave head time, and perform dual-end ranging on all effective paths in turn according to the following formula based on the first wave head time: Where, d xy is the two-terminal traveling wave ranging result of the shortest path from end point x to end point y, L xy is the length of the shortest path from endpoint x to endpoint y, t x and t y is the first wave head moment corresponding to the fault traveling wave current waveform at endpoints x and y; v is the traveling wave velocity.

6. The method according to claim 1, characterized in that: The method of determining whether the fault point is located on the valid path according to the double-end ranging result and the path distance array of each valid path in turn is as follows: the double-end ranging result is compared with the elements in the path distance array in turn, if the difference between the ranging result and a certain element is less than a first preset deviation threshold, the fault point is not on the valid path, otherwise the fault point is on the valid path; The method of further determining the fault section on the valid path and the distance measurement result from one end of the fault section according to the boundary position array is as follows: determining between which two elements of the path distance array the double-end distance measurement result is located, determining the fault section according to the corresponding relationship between the two elements and the boundary position array, and subtracting the smaller of the two elements from the double-end distance measurement result to obtain the distance measurement result from one end of the fault section.

7. The method according to claim 1, characterized in that: The final fault section is determined comprehensively based on all fault sections and the distance measurement results from one end of the fault section, specifically: all fault sections are counted, and the fault section with the most occurrences is taken as the final fault section; The final distance measurement result is calculated according to the distance measurement result of one end of the fault section corresponding to the final fault section.

8. The method according to claim 7, characterized in that: The final distance measurement result is calculated as follows: let the number of occurrences of the faulty section with the largest number of occurrences be sum_valid0, and the average value of the distance measurement results corresponding to sum_valid0 at one end of the faulty section is taken as the final distance measurement result.

9. The method according to claim 7, characterized in that: The final ranging result calculation method is as follows: let the number of occurrences of the fault section with the largest number of occurrences be sum_valid0, calculate the average value of the ranging results at one end of the distance fault section corresponding to sum_valid0, eliminate the ranging results at one end of the distance fault section whose deviation from the average value exceeds the second preset deviation threshold to obtain the valid ranging result, and calculate the average value of the valid ranging results as the final ranging result.

10. A distribution network fault location system, characterized in that: include: Traveling wave acquisition devices are installed at all endpoints of the distribution network; The traveling wave acquisition device acquires the fault traveling wave current waveform when a fault occurs and sends it to the ranging master station; The ranging master station includes a transmission path acquisition unit, a waveform acquisition unit, a dual-end ranging unit, an initial determination unit and a comprehensive determination unit; wherein: The transmission path acquisition unit is used to obtain the shortest traveling wave transmission path between two N endpoints according to the distribution network topology, and obtain traveling wave transmission paths and the corresponding path distance array and boundary position array; where N is the total number of endpoints of the distribution network; The waveform acquisition unit is used to acquire the fault traveling wave current waveform sent by all traveling wave acquisition devices, and acquire the effective waveform and effective path; The dual-end distance measurement unit is used to perform wavelet decomposition on the effective waveform and perform dual-end distance measurement on all effective paths in sequence; The initial determination unit is used to determine whether the fault point is located on the valid path according to the double-end distance measurement result of each valid path and the path distance array in turn, and if so, further determine the fault section on the valid path and the distance measurement result of one end of the fault section according to the boundary position array; The comprehensive determination unit is used to comprehensively determine the final fault section and the distance measurement result according to all the fault sections and the distance measurement results at one end of the fault section.

11. An electronic device, characterized in that: include: processor; as well as A memory storing computer instructions, which, when executed by the processor, causes the processor to execute the method according to any one of claims 1 to 9.

12. A non-transitory computer storage medium, characterized in that: A computer program is stored, and when the computer program is executed by multiple processors, the processors are caused to execute the method according to any one of claims 1 to 9.

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