A method and apparatus for locating fault sections in a distribution network based on an FTU

Abstract

This invention relates to a method and apparatus for locating fault sections in a distribution network based on an FTU (Fault Transmission Unit). The method includes: classifying edge nodes and non-edge nodes, and establishing distortion judgment criteria for each; determining whether there are distorted nodes among the edge nodes; if not, obtaining an initial fault section based on the fault information of the edge nodes; if so, correcting the distortion information of all distorted nodes in the edge nodes to obtain the initial fault section; determining whether there are distorted nodes among the adjacent nodes of the initial fault section; if not, correcting the fault information of the adjacent nodes to obtain the result fault section; if so, correcting the distortion information of all distorted nodes in the adjacent nodes to obtain the true node fault information of the adjacent nodes to obtain the result fault section. Compared with the prior art, this invention has advantages such as preventing false fault area identification and fast fault area location.

Description

Technical Field

[0001] This invention relates to the field of distribution network fault location, and in particular to a method and apparatus for locating fault sections in a distribution network based on an FTU. Background Technology

[0002] As the hub directly connecting the power system and users, the distribution network directly impacts the reliability of power supply. With the widespread adoption of distribution network automation, fault locations in the distribution network can now be determined using telemetry and tele-signaling information from feeder terminal units (FTUs). When a fault occurs in the distribution network, the fault information detected by the FTU at the pole-mounted switch is transmitted to the distribution network master station via configured communication equipment. The master station then processes the fault information to locate the fault section.

[0003] Currently, methods for locating fault sections based on FTU (Fault Transfer Unit) mainly utilize FTU telemetry and telemetry information to pinpoint fault sections in the distribution network. Methods based on FTU telemetry information primarily include matrix algorithms and artificial intelligence algorithms. Matrix algorithms are popular due to their high computational speed. However, when the telemetry information uploaded by the FTU is distorted, the fault location obtained solely through matrix algorithms may not accurately reflect the actual fault section, leading to misjudgments and unreliable fault location results. FTU telemetry information-based fault location primarily utilizes electrical quantities such as voltage amplitude and current phase angle difference. While FTU telemetry information is less prone to distortion and thus has high fault tolerance, it requires processing large amounts of data, hindering rapid fault location in the distribution network.

[0004] In summary, current methods for locating distribution network fault areas using matrix algorithms based on FTU telemetry information suffer from misjudgment, while methods based on FTU telemetry information involve large computational loads and slow location speed. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art by providing a method and device for locating fault sections in a distribution network based on FTU, which prevents false fault identification and has a fast fault area location speed.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for locating fault sections in a distribution network based on an FTU includes the following steps:

[0008] Based on the connection relationship between distribution network nodes, the distribution network nodes are classified into edge nodes and non-edge nodes, and distortion judgment criteria are established for the edge nodes and the non-edge nodes respectively.

[0009] Based on the distortion criteria of edge nodes, it is determined whether there are distorted nodes among the edge nodes. If not, the initial fault segment is obtained based on the fault information of the edge nodes.

[0010] If it exists, then all distorted nodes in the edge nodes are distorted to correct the distortion information, and the true node fault information of the edge nodes is obtained. Based on the true node fault information of the edge nodes, the initial fault segment is obtained.

[0011] Based on the distortion judgment criteria of edge nodes and non-edge nodes, it is determined whether there are distorted nodes among the adjacent nodes of the initial fault segment. If not, the fault information of the adjacent nodes is corrected, the initial fault segment is updated, and the resulting fault segment is obtained.

[0012] If it exists, then all distorted nodes in the adjacent nodes are distorted to correct the distortion information, and the true node fault information of the adjacent nodes is obtained. The initial fault segment is updated based on the true node fault information of the adjacent nodes to obtain the result fault segment.

[0013] Furthermore, distortion information correction is performed on all distorted nodes to obtain the specific details of the true node fault information:

[0014] The distortion information of the distorted nodes is corrected. The specific correction process is as follows:

[0015] The system collects three-phase currents of distorted nodes based on telemetry information from FTUs. A fault function is then set based on the collected three-phase currents and pre-configured fault currents. The value of the fault function is used as the node fault information.

[0016] The expression for the fault function is:

[0017]

[0018] Among them, K' i For the fault function, I i Let I be the three-phase current of the i-th phase at the collected node. set For pre-configured fault current;

[0019] If the node fault information is inconsistent with the alarm information provided by the FTU's remote signaling information, the alarm information will be corrected to the node fault information.

[0020] Repeat the above steps until the distortion information of all distorted nodes in the node is corrected;

[0021] After correcting the distortion information of all distorted nodes, the corrected alarm information is used as the actual node fault information.

[0022] Furthermore, the classification of distribution network nodes based on the connection relationship between distribution network nodes to obtain edge nodes and non-edge nodes specifically involves: the nodes of the feeder terminal and the nodes adjacent to the main power source are regarded as edge nodes, and the remaining nodes are regarded as non-edge nodes.

[0023] Furthermore, the distortion judgment criteria for the edge nodes and the non-edge nodes are established as follows:

[0024] Edge nodes are classified into primary edge nodes, secondary edge nodes, and ordinary edge nodes. Non-edge nodes are classified into ordinary nodes, dual-parent nodes, and dual-child nodes.

[0025] For a primary edge node, if the reported information of the node and its child nodes are 0, 1 or -1, 0 or -1, 1 respectively, then the primary edge node is determined to be a distorted node.

[0026] For a slave edge node with only one parent node, if the reported information of the node and its parent node are 1 and -1, or 1 and 0, or 0 and -1 respectively, then the slave edge node is determined to be a distorted node.

[0027] For a slave edge node with two parent nodes, if the reported information of the node and its main parent node are 0 and -1 respectively, the slave edge node is determined to be a distorted node.

[0028] For a normal edge node, if the reported information of the node and its main parent node are 1 and 0 respectively, or the reported information of the node is -1, then the normal edge node is determined to be a distorted node.

[0029] For a normal node, if the reported information of the node's parent node and the node's child node is the same, but different from the reported information of the normal node, then the normal node is judged to be a distorted node.

[0030] For nodes with two parent nodes:

[0031] When the reported information from the parent node of this node is 0, and the reported information from this node, its parent node, and its child nodes are 0, 1, 1, or 1, 0, 0, or -1, 0, 0, or 0, -1, -1 respectively,

[0032] Alternatively, when the reported information from the parent node is 1, and the reported information from the node, its parent node, and its child nodes are 0, 1, 1, or 0, -1, -1, or -1, 1, 1, or 1, -1, -1, respectively,

[0033] Alternatively, when the reported information from the child node is -1, and the reported information from the child node, its parent node, and its child node are 0, -1, -1, or 0, 1, 1, or -1, -1, 1, or -1, 1, 1 respectively,

[0034] Then the node with two parent nodes is determined to be a distorted node;

[0035] For twin nodes:

[0036] When the reported information from the child node of a node is 0, and the reported information from the node, its parent node, and its master-child node are 0, 1, 1, or 1, 0, 0, or -1, 0, 0, or 0, -1, -1 respectively,

[0037] Alternatively, when the reported information from the child node of this node is 1, and the reported information from this node, its parent node, and its master-child node are 0, 1, 0, -1, 1, 0, 1, -1, -1, -0, -1, -1 respectively,

[0038] Or, when the reported information from the child node of this node is -1, and the reported information from this node, its parent node, and its master-child node are 1, -1, 0, or 0, -1, 0, or 0, 1, 1 respectively,

[0039] Then the twin node is determined to be a distorted node.

[0040] Furthermore, the classification of edge nodes into primary edge nodes, secondary edge nodes, and ordinary edge nodes, and the classification of non-edge nodes into ordinary nodes, dual-parent nodes, and dual-child nodes, are specifically as follows:

[0041] If an edge node is adjacent to the main power source in the distribution network, then the edge node is determined to be a main edge node.

[0042] When an edge node is adjacent to a distributed generation (DG) in the distribution network, it is determined to be a slave edge node.

[0043] If an edge node is not adjacent to any power source, it is determined to be a normal edge node.

[0044] If a non-edge node has only one adjacent node upstream and downstream, then the non-edge node is determined to be a normal node.

[0045] If a non-edge node has two adjacent upstream nodes and only one adjacent downstream node, then the non-edge node is determined to be a double-parent node.

[0046] If a non-edge node has only one upstream neighbor and two downstream neighbors, then the non-edge node is considered a twin node.

[0047] A fault location device for a distribution network based on an FTU includes a memory, a processor, and a program stored in the memory. When the processor executes the program, it performs the steps described above.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] (1) For the fault segment obtained by identifying the edge node as a distorted node, further calculate whether the adjacent node of the fault segment is a distorted node. If not, update the fault information to prevent false alarms in the fault information obtained by using only the matrix algorithm, which would cause false fault segments and expand the fault area.

[0050] (2) In the process of correcting the distortion information of the distorted node, the three-phase current of the distorted node is collected by the telemetry information based on the FTU, and the alarm information provided by the telemetry information of the FTU is corrected. This ensures the accuracy of the alarm information and reduces the amount of calculation compared with directly using the telemetry information of the FTU to locate the fault area. Attached Figure Description

[0051] Figure 1 This is a flowchart of the present invention;

[0052] Figure 2 This is a structural diagram of a DG-containing power distribution network system according to an embodiment of the present invention. Detailed Implementation

[0053] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0054] A method for locating fault sections in a distribution network based on FTU, such as Figure 1 As shown, the steps include: classifying nodes and establishing distortion judgment criteria; determining whether there are distorted nodes among the edge nodes; if not, obtaining an initial fault segment based on the fault information of the edge nodes; if so, correcting the distortion information of the distorted nodes; after correcting all distorted nodes, obtaining the initial fault segment using a matrix algorithm based on the real node fault information of the edge nodes obtained after correction; determining whether there are distorted nodes among the adjacent nodes of the initial fault segment; if so, correcting the distortion information of the distorted nodes; after correcting all distorted nodes, updating the initial fault segment using a matrix algorithm based on the real node fault information of the adjacent nodes obtained after correction, and obtaining the result fault segment; if there are no distorted nodes, correcting the fault information of the adjacent nodes, updating the initial fault segment, and obtaining the result fault segment.

[0055] Classify nodes and establish criteria for distortion judgment.

[0056] The nodes at the feeder terminal and those adjacent to the main power supply are defined as edge nodes, and the remaining nodes are called non-edge nodes. Edge nodes are classified into master edge nodes, slave edge nodes, and ordinary edge nodes, while non-edge nodes are classified into ordinary nodes, dual-parent nodes, and dual-child nodes.

[0057] If an edge node is adjacent to the main power source in the distribution network, then the edge node is determined to be a main edge node.

[0058] When an edge node is adjacent to a distributed generation (DG) in the distribution network, it is determined to be a slave edge node.

[0059] If an edge node is not adjacent to any power source, it is determined to be a normal edge node.

[0060] If a non-edge node has only one adjacent node upstream and downstream, then the non-edge node is determined to be a normal node.

[0061] If a non-edge node has two adjacent upstream nodes and only one adjacent downstream node, then the non-edge node is determined to be a double-parent node.

[0062] If a non-edge node has only one upstream neighbor and two downstream neighbors, then the non-edge node is considered a twin node.

[0063] Further establish distortion judgment criteria based on node classification:

[0064] 1) Criterion for determining whether an edge node is a distorted node:

[0065] ① For a primary edge node, if the information reported by the node and its child nodes are 0, 1 or -1, 0 or -1, 1 respectively, then the node can be determined to be a distorted node;

[0066] ② For a slave edge node with only one parent node, if the information reported by the node and its parent node are 1 and -1, or 1 and 0, or 0 and -1 respectively, the node can be determined to be a distorted node;

[0067] ③ For a slave edge node with two parent nodes, if the information reported by the node and its master parent node are 0 and -1 respectively, the node can be determined to be a distorted node;

[0068] ④ For ordinary edge nodes, if the information reported by the node and its main parent node is 1 and 0 respectively, or the information reported by the node is -1, then the node can be determined to be a distorted node.

[0069] 2) Criterion for non-edge nodes to be distorted nodes

[0070] ① For a normal node, if the information reported by the parent and child nodes of the node is the same but different from the information reported by the normal node, then the node can be determined to be a malformed node;

[0071] ② For a node with two parent nodes, scenario 1: when the information reported by the node's secondary parent node is 0, and the information reported by the node, its primary parent node, and its child node are 0, 1, 1 or 1, 0, 0 or -1, 0, 0 or 0, -1, -1 respectively; scenario 2: when the information reported by the node's secondary parent node is 1, and the information reported by the node, its primary parent node, and its child node are 0, 1, 1 or 0, -1, -1 or -1, 1, 1 or 1, -1, -1 respectively; scenario 3: when the information reported by the node's secondary parent node is -1, and the information reported by the node, its primary parent node, and its child node are 0, -1, -1 or 0, 1, 1 or -1, -1, 1 or -1, 1, 1 respectively; if the node with two parent nodes meets any of the above three scenarios, it can be determined that the node is a distorted node;

[0072] ③ For twin-child nodes, scenario 1: when the information reported by the child node of the node is 0, and the information reported by the node, its parent node, and its master-child node are 0, 1, 1 or 1, 0, 0 or -1, 0, 0 or 0, -1, -1 respectively; scenario 2: when the information reported by the child node of the node is 1, and the information reported by the node, its parent node, and its master-child node are 0, 1, 0 or -1, 1, 0 or 1, -1, -1 or -0, -1, -1 respectively; scenario 3: when the information reported by the child node of the node is -1, and the information reported by the node, its parent node, and its master-child node are 1, -1, 0 or 0, -1, 0 or 0, 1, 1 respectively; if the twin-child node meets any of the above three scenarios, the node can be determined to be a distorted node.

[0073] Determine whether there are distorted nodes at the edge nodes. If so, correct the distortion information of the distorted nodes. After correcting all distorted nodes, use a matrix algorithm to obtain the initial fault segment based on the real node fault information of the edge nodes obtained after correction.

[0074] The process of distortion correction is as follows:

[0075] The system collects three-phase currents of distorted nodes based on telemetry information from FTUs. A fault function is then set based on the collected three-phase currents and pre-configured fault currents. The value of the fault function is used as the node fault information.

[0076] The expression for the fault function is:

[0077]

[0078] Among them, K' i For the fault function, I i Let I be the three-phase current of the i-th phase at the collected node.set For the pre-configured fault current, K′ i =1 indicates that a fault has occurred in this phase and the direction of the fault current is in the specified positive direction; K′ i =0 indicates that the phase is not faulty; K′ i =-1 indicates that the phase is faulty and the direction of the fault current is opposite to the specified positive direction.

[0079] If the node fault information is inconsistent with the alarm information provided by the FTU's remote signaling information, the alarm information will be corrected to the node fault information, and the distortion information correction steps will be repeated until the distortion information correction is completed for all distorted nodes in the edge nodes.

[0080] After correcting the distortion information of all distorted nodes in the edge nodes, the corrected alarm information is used as the actual node fault information.

[0081] Based on the real node fault information of the edge nodes obtained after distortion correction, a fault information matrix is ​​obtained. The initial fault segment is obtained by using a matrix algorithm. The established network description matrix D is multiplied by the fault information matrix G to obtain matrix Y. Then, the fault judgment vector is calculated, and the initial fault segment is obtained based on the fault judgment vector.

[0082] The specific calculation process is as follows:

[0083] Y = D × G

[0084] P1 = abs(Y) × e n

[0085] P2=Y×e n

[0086] P = P1[&]P2

[0087] Where any element y in matrix Y ij The meaning it represents is: y ij =1 indicates that the FTU at node j detected a fault current flowing into device i; y ij =-1 indicates that the FTU at node j detected a fault current flowing out of device i.

[0088] Since adjacent nodes of the faulty device cannot detect the fault current flowing out of the device, all elements in the row containing the faulty device in matrix Y are greater than or equal to 0. If the fault judgment vector P has an element P... i1 If the value is 1, it can be determined that device i has malfunctioned, and the fault area can be identified.

[0089] abs(Y) performs the absolute value operation on all elements of matrix Y; nP1[&]P2 is an n-dimensional column vector with all elements being 1; P1[&]P2 is the AND operation performed on the corresponding elements of vectors P1 and P2.

[0090] The elements in matrix D are:

[0091]

[0092] Determine whether there are distorted nodes among the adjacent nodes of the initial fault segment. If so, perform distortion information correction on the distorted nodes. After completing the correction of all distorted nodes, update the initial fault segment using a matrix algorithm based on the real node fault information of the adjacent nodes obtained after correction, and obtain the result fault segment.

[0093] The method for correcting the distortion information of distorted nodes in adjacent nodes and obtaining the resulting fault segment is the same as the method for correcting the distortion information of distorted nodes in edge nodes and obtaining the initial fault segment.

[0094] If no distorted nodes exist, update the initial faulty section to obtain the resulting faulty section.

[0095] This embodiment also provides a distribution network fault section location device based on FTU, including a memory, a processor, and a program stored in the memory. When the processor executes the program, it implements the above steps.

[0096] The following example will verify this:

[0097] 1. Location of single faults

[0098] by Figure 2 Taking the DG-containing distribution network system as an example, simulation tests were conducted on the system when faults occurred at different locations. The test results are shown in Tables 1 and 2.

[0099] for Figure 2 The network description matrix D for the DG-containing distribution network system shown is:

[0100]

[0101] Detailed analysis of Tables 1 and 2 reveals the following: Example 1: A fault occurs in section L1 of the distribution network, and node 1 experiences a false alarm. Based on the distorted node identification criterion proposed in this invention, node 1 can be identified as a distorted node. Therefore, only the identified distorted node 1 and its adjacent node 2 (as determined by the matrix algorithm) need correction. Example 2: A fault occurs in section L6 of the distribution network, with node 8 experiencing a false alarm and node 18 failing to report a fault. Based on this invention, nodes 8 and 18 can be identified as distorted nodes. Therefore, only the identified distorted nodes and their adjacent nodes 6, 7, and 26 (as determined by the matrix algorithm) need correction. Example 3: A faulty section in the distribution network is set to L12, and nodes 7 and 8 experience distortion. Based on this invention, nodes 7 and 8 can be identified as distorted nodes. Therefore, only the identified distorted nodes 7 and 8 and their adjacent nodes (as determined by the matrix algorithm) need correction. Example 4 tests the distribution network fault section set to L25 and the node 25 adjacent to the fault section is missed. Since the distortion of node 25 is an unidentifiable distortion, it is impossible to identify whether node 25 is a distorted node. However, according to the fault location process of the present invention, the fault location of the distribution network under such distortion can be realized.

[0102] A comparison of Tables 1 and 2 shows that the fault location method of the present invention can accurately locate single faults in the distribution network.

[0103] Table 1. Single fault location based on matrix algorithm

[0104] Calculation example Set fault section FTU uploads fault information sequence Location results 1 L1 [-1*18 0*7 -1*8] none 2 L6 [1*6 -1 1 -1*9 0*8 -1*8] L6, L8 3 L12 [1*6 -1 1*5 -1*6 0*7 -1*2 0 -1*5] L6, L12, L28 4 L25 [1*3 -1*15 0*4 1*2 0 -1*8] L24

[0105] For example, in the FTU upload fault information sequence [-1*18 0*7 -1*8] of Example 1, -1*18 means that the fault information values ​​from node 1 to node 18 are all -1, and so on.

[0106] Table 2 Single Fault Location Based on the Invention

[0107]

[0108] 2. Location of dual faults

[0109] The simulation results of locating fault sections in the power distribution network using the method proposed in this invention are shown in Tables 3 and 4.

[0110] A detailed analysis of Tables 3 and 4 reveals the following: In Example 1, when faults occur simultaneously in L1 and L9 and a false alarm occurs at node 2 adjacent to segment L1, the fault location result obtained solely through the matrix algorithm does not include the true fault segment L1. Example 2 verifies that in cases of faults in L6 and L12, false alarms originating from edge node 18 lead to pseudo-fault segments, expanding the scope of the fault segment. Examples 3-6 all verify that when multiple faults occur in the distribution network and there are distortions in adjacent nodes of non-true fault segments, false faults will occur if fault location is achieved solely through the matrix algorithm. To address these issues, the fault location method proposed in this invention only requires correction of the identified distorted nodes and some specific nodes to obtain the true fault segment.

[0111] As shown in Tables 1 and 4, the present invention can still accurately locate the faulty section of the distribution network when single or multiple faults occur and information distortion exists.

[0112] Table 3. Multiple fault localization based on matrix algorithm

[0113]

[0114] Table 4. Multiple Fault Location Based on the Invention

[0115]

[0116] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A fault section location method for power distribution network based on FTU, characterized in that, Includes the following steps: Based on the connection relationship between distribution network nodes, the distribution network nodes are classified into edge nodes and non-edge nodes, and distortion judgment criteria are established for the edge nodes and the non-edge nodes respectively. Based on the distortion criteria of edge nodes, it is determined whether there are distorted nodes among the edge nodes. If not, the initial fault segment is obtained based on the fault information of the edge nodes. If it exists, then all distorted nodes in the edge nodes are distorted to correct the distortion information, and the true node fault information of the edge nodes is obtained. Based on the true node fault information of the edge nodes, the initial fault segment is obtained. Based on the distortion judgment criteria of edge nodes and non-edge nodes, it is determined whether there are distorted nodes among the adjacent nodes of the initial fault segment. If not, the fault information of the adjacent nodes is corrected, the initial fault segment is updated, and the resulting fault segment is obtained. If it exists, then all distorted nodes in the adjacent nodes are distorted to correct the distortion information, and the true node fault information of the adjacent nodes is obtained. The initial fault segment is updated based on the true node fault information of the adjacent nodes to obtain the result fault segment. The classification of distribution network nodes based on the connection relationship between distribution network nodes to obtain edge nodes and non-edge nodes is specifically as follows: the nodes of the feeder terminal and the nodes adjacent to the main power source are regarded as edge nodes, and the remaining nodes are regarded as non-edge nodes. The specific criteria for establishing distortion judgment for the edge nodes and the non-edge nodes are as follows: Edge nodes are classified into primary edge nodes, secondary edge nodes, and ordinary edge nodes. Non-edge nodes are classified into ordinary nodes, dual-parent nodes, and dual-child nodes. For a primary edge node, if the reported information of the node and its child nodes are 0, 1 or -1, 0 or -1, 1 respectively, then the primary edge node is determined to be a distorted node. For a slave edge node with only one parent node, if the reported information of the node and its parent node are 1 and -1, or 1 and 0, or 0 and -1 respectively, then the slave edge node is determined to be a distorted node. For a slave edge node with two parent nodes, if the reported information of the node and its main parent node are 0 and -1 respectively, the slave edge node is determined to be a distorted node. For a normal edge node, if the reported information of the node and its main parent node are 1 and 0 respectively, or the reported information of the node is -1, then the normal edge node is determined to be a distorted node. For a normal node, if the reported information of the node's parent node and the node's child node is the same, but different from the reported information of the normal node, then the normal node is judged to be a distorted node. For nodes with two parent nodes: When the reported information from the parent node of this node is 0, and the reported information from this node, its parent node, and its child nodes are 0, 1, 1, or 1, 0, 0, or -1, 0, 0, or 0, -1, -1 respectively, Alternatively, when the reported information from the parent node is 1, and the reported information from the node, its parent node, and its child nodes are 0, 1, 1, or 0, -1, -1, or -1, 1, 1, or 1, -1, -1, respectively, Alternatively, when the reported information from the child node is -1, and the reported information from the child node, its parent node, and its child node are 0, -1, -1, or 0, 1, 1, or -1, -1, 1, or -1, 1, 1 respectively, Then the node with two parent nodes is determined to be a distorted node; For twin nodes: When the reported information from the child node of a node is 0, and the reported information from the node, its parent node, and its master-child node are 0, 1, 1, or 1, 0, 0, or -1, 0, 0, or 0, -1, -1 respectively, Alternatively, when the reported information from the child node of this node is 1, and the reported information from this node, its parent node, and its master-child node are 0, 1, 0, -1, 1, 0, 1, -1, -1, -0, -1, -1 respectively, Or, when the reported information from the child node of this node is -1, and the reported information from this node, its parent node, and its master-child node are 1, -1, 0, or 0, -1, 0, or 0, 1, 1 respectively, Then the twin node is determined to be a distorted node.

2. The FTU-based distribution network fault section location method of claim 1, wherein, The distortion information of all distorted nodes is corrected to obtain the actual node fault information as follows: The distortion information of the distorted nodes is corrected. The specific correction process is as follows: The system collects three-phase currents of distorted nodes based on telemetry information from the FTU. A fault function is then set based on the collected three-phase currents and a pre-configured fault current. The value of the fault function is used as the node fault information. The expression for the fault function is: in, For fault functions, For the collected nodes i Three-phase current, For pre-configured fault current; If the node fault information is inconsistent with the alarm information provided by the FTU's remote signaling information, the alarm information will be corrected to the node fault information. Repeat the above steps until the distortion information of all distorted nodes in the node is corrected; After correcting the distortion information of all distorted nodes, the corrected alarm information is used as the actual node fault information.

3. The method for locating fault sections in a distribution network based on an FTU according to claim 1, characterized in that, The process of classifying edge nodes into primary edge nodes, secondary edge nodes, and ordinary edge nodes, and classifying non-edge nodes into ordinary nodes, dual-parent nodes, and dual-child nodes, is as follows: If an edge node is adjacent to the main power source in the distribution network, then the edge node is determined to be a main edge node. When an edge node is adjacent to a distributed generation (DG) in the distribution network, it is determined to be a slave edge node. If an edge node is not adjacent to any power source, it is determined to be a normal edge node. If a non-edge node has only one adjacent node upstream and downstream, then the non-edge node is determined to be a normal node. If a non-edge node has two adjacent upstream nodes and only one adjacent downstream node, then the non-edge node is determined to be a double-parent node. If a non-edge node has only one upstream neighbor and two downstream neighbors, then the non-edge node is considered a twin node.

4. A distribution network fault section location device based on FTU, characterized in that, Includes a memory, a processor, and a program stored in the memory, wherein the processor executes the program to perform the following steps: Based on the connection relationship between distribution network nodes, the distribution network nodes are classified into edge nodes and non-edge nodes, and distortion judgment criteria are established for the edge nodes and the non-edge nodes respectively. Based on the distortion criteria of edge nodes, it is determined whether there are distorted nodes among the edge nodes. If not, the initial fault segment is obtained based on the fault information of the edge nodes. If it exists, then all distorted nodes in the edge nodes are distorted to correct the distortion information, and the true node fault information of the edge nodes is obtained. Based on the true node fault information of the edge nodes, the initial fault segment is obtained. Based on the distortion judgment criteria of edge nodes and non-edge nodes, it is determined whether there are distorted nodes among the adjacent nodes of the initial fault segment. If not, the fault information of the adjacent nodes is corrected, the initial fault segment is updated, and the resulting fault segment is obtained. If it exists, then all distorted nodes in the adjacent nodes are distorted to correct the distortion information, and the true node fault information of the adjacent nodes is obtained. The initial fault segment is updated based on the true node fault information of the adjacent nodes to obtain the result fault segment. The classification of distribution network nodes based on the connection relationship between distribution network nodes to obtain edge nodes and non-edge nodes is specifically as follows: the nodes of the feeder terminal and the nodes adjacent to the main power source are regarded as edge nodes, and the remaining nodes are regarded as non-edge nodes. The specific criteria for establishing distortion judgment for the edge nodes and the non-edge nodes are as follows: Edge nodes are classified into primary edge nodes, secondary edge nodes, and ordinary edge nodes. Non-edge nodes are classified into ordinary nodes, dual-parent nodes, and dual-child nodes. For a primary edge node, if the reported information of the node and its child nodes are 0, 1 or -1, 0 or -1, 1 respectively, then the primary edge node is determined to be a distorted node. For a slave edge node with only one parent node, if the reported information of the node and its parent node are 1 and -1, or 1 and 0, or 0 and -1 respectively, then the slave edge node is determined to be a distorted node. For a slave edge node with two parent nodes, if the reported information of the node and its main parent node are 0 and -1 respectively, the slave edge node is determined to be a distorted node. For a normal edge node, if the reported information of the node and its main parent node are 1 and 0 respectively, or the reported information of the node is -1, then the normal edge node is determined to be a distorted node. For a normal node, if the reported information of the node's parent node and the node's child node is the same, but different from the reported information of the normal node, then the normal node is judged to be a distorted node. For nodes with two parent nodes: When the reported information from the parent node of this node is 0, and the reported information from this node, its parent node, and its child nodes are 0, 1, 1, or 1, 0, 0, or -1, 0, 0, or 0, -1, -1 respectively, Alternatively, when the reported information from the parent node is 1, and the reported information from the node, its parent node, and its child nodes are 0, 1, 1, or 0, -1, -1, or -1, 1, 1, or 1, -1, -1, respectively, Alternatively, when the reported information from the child node is -1, and the reported information from the child node, its parent node, and its child node are 0, -1, -1, or 0, 1, 1, or -1, -1, 1, or -1, 1, 1 respectively, Then the node with two parent nodes is determined to be a distorted node; For twin nodes: When the reported information from the child node of a node is 0, and the reported information from the node, its parent node, and its master-child node are 0, 1, 1, or 1, 0, 0, or -1, 0, 0, or 0, -1, -1 respectively, Alternatively, when the reported information from the child node of this node is 1, and the reported information from this node, its parent node, and its master-child node are 0, 1, 0, -1, 1, 0, 1, -1, -1, -0, -1, -1 respectively, Or, when the reported information from the child node of this node is -1, and the reported information from this node, its parent node, and its master-child node are 1, -1, 0, or 0, -1, 0, or 0, 1, 1 respectively, Then the twin node is determined to be a distorted node.

5. A distribution network fault section location device based on FTU according to claim 4, characterized in that, The distortion information of all distorted nodes is corrected to obtain the actual node fault information as follows: The distortion information of the distorted nodes is corrected. The specific correction process is as follows: The system collects three-phase currents of distorted nodes based on telemetry information from the FTU. A fault function is then set based on the collected three-phase currents and a pre-configured fault current. The value of the fault function is used as the node fault information. The expression for the fault function is: in, For fault functions, Let be the three-phase current of the i-th phase at the collected node. For pre-configured fault current; If the node fault information is inconsistent with the alarm information provided by the FTU's remote signaling information, the alarm information will be corrected to the node fault information. Repeat the above steps until the distortion information of all distorted nodes in the node is corrected; After correcting the distortion information of all distorted nodes, the corrected alarm information is used as the actual node fault information.

6. A distribution network fault location device based on FTU according to claim 4, characterized in that, The process of classifying edge nodes into primary edge nodes, secondary edge nodes, and ordinary edge nodes, and classifying non-edge nodes into ordinary nodes, dual-parent nodes, and dual-child nodes, is as follows: If an edge node is adjacent to the main power source in the distribution network, then the edge node is determined to be a main edge node. When an edge node is adjacent to a distributed generation (DG) in the distribution network, it is determined to be a slave edge node. If an edge node is not adjacent to any power source, it is determined to be a normal edge node. If a non-edge node has only one adjacent node upstream and downstream, then the non-edge node is determined to be a normal node. If a non-edge node has two adjacent upstream nodes and only one adjacent downstream node, then the non-edge node is determined to be a double-parent node. If a non-edge node has only one upstream neighbor and two downstream neighbors, then the non-edge node is considered a twin node.

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