Distribution line fault positioning method based on adaptive relation matrix

Abstract

The invention discloses a distribution line fault positioning method based on an adaptive relation matrix, which overcomes the problems of low positioning accuracy and low positioning speed of a distribution line fault positioning method in the prior art, and comprises the following steps: constructing an N-dimensional network topology matrix according to the number of distribution line switches; monitoring whether the power system has a fault or not in real time, if so, acquiring fault information, and judging a fault occurrence position by using a fault positioning method; if no fault occurs, detecting the change of the topological structure of the power system, if the change of the topological structure of the power system exists, performing adaptive adjustment on the N-dimensional network topological matrix, and then monitoring whether the power system has the fault in real time; otherwise, directly monitoring whether the power system has a fault or not in real time. The method can adapt to the change of the topological structure of the distribution line, and can quickly and accurately position all fault points when the line breaks down, thereby providing an accurate basis for further fault isolation and power supply recovery, and improving the power supply reliability of the system.

Description

Technical Field

[0001] This invention relates to the field of power line fault location technology, and in particular to a method for power distribution line fault location based on an adaptive relation matrix. Background Technology

[0002] With the development of modern power systems and the acceleration of urbanization, the scale and complexity of power distribution networks are constantly increasing. As a crucial component of the power system, the safe and reliable operation of distribution lines directly affects the stability of the power system and the normal electricity demand of users. However, distribution line faults occur frequently, making rapid and accurate fault location one of the key issues in power system operation and maintenance.

[0003] Traditional fault location methods mainly rely on line inspections and simple electrical parameter measurements. These methods are not only time-consuming and labor-intensive, but also have low location accuracy in complex power distribution networks, making it difficult to meet the requirements of modern power distribution systems for rapid fault handling. Existing fault location technologies mainly include fault location methods based on electrical quantity characteristic analysis, fault location methods based on waveform signal analysis, and fault location methods based on topology analysis. These methods have improved the accuracy and speed of fault location to some extent, but still have some shortcomings. For example, electrical quantity characteristic analysis methods are susceptible to load changes and environmental factors, waveform signal analysis methods have high requirements for data acquisition equipment, and topology analysis methods have limited location accuracy in complex networks and are not suitable for situations with topology changes, i.e., they require manual updates to the topology matrix. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of low accuracy and speed in existing power distribution line fault location methods. It provides a power distribution line fault location method based on an adaptive relation matrix, which can adapt to changes in the power distribution line topology and quickly and accurately locate all fault points when a fault occurs in the line. This provides an accurate basis for further fault isolation and power restoration, thereby improving the power supply reliability of the system.

[0005] The network topology of the power distribution line is stored in matrix form. When a fault occurs in the power distribution line, the fault direction information identified by each terminal on the line is collected, and the location of the fault is determined by combining the system topology before the fault.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A method for fault location in power distribution lines based on an adaptive relation matrix, characterized by comprising the following steps: S1: Construct an N-dimensional network topology matrix based on the number of switches in the power distribution lines; S2: Monitor the power system in real time to see if any faults occur. If a fault occurs, proceed to step S3; otherwise, proceed to step S4. S3: Obtain fault information and use fault location methods to determine the location of the fault. S4: If a change in the power system topology is detected, return to step S1 to perform adaptive topology adjustment; otherwise, return to step S2.

[0007] By storing the network topology of power distribution lines in matrix form, when a fault occurs in a power distribution line, the fault direction information identified by each terminal on the line is collected, and the location of the fault is determined by combining this information with the system topology before the fault. This allows for adaptive adaptation to changes in the power distribution line topology, enabling rapid and accurate location of all fault points when a fault occurs. This provides an accurate basis for further fault isolation and power restoration, improving the reliability of the system's power supply.

[0008] Preferably, the fault location method includes: S3.1: Determine the fault direction for each terminal on the power distribution line and generate an N-dimensional fault information matrix; S3.2: Add the network topology matrix and the fault information matrix to obtain the fault location discrimination matrix Z; S3.3: Based on the values ​​of the elements in the fault location discrimination matrix, determine the fault location and output the fault point; S3.4: If the fault point output in step S3.3 is the only fault point, then output the fault point and end the current fault location; otherwise, find and output other fault points.

[0009] Preferably, in step S3.3: Z satisfies ii The maximum value of i = 1, if for any j Z = 1 ij =0, and j≠i, then the feeder segment at the end of node i is faulty; if there exists a unique j, and j≠i, satisfying Z ij =1, then the interval between nodes i and j is determined to be a fault zone; if there exist j, k, j≠i, k≠i and k≠j, satisfying Z ij =1,Z ik If the value is 1, then the section between nodes i, j, and k is considered a faulty section.

[0010] As a preferred option, for satisfying Z ii The maximum value of i = 1, if there exists m satisfying Z mm =1, m≠i, and does not satisfy Z mi =1 and does not satisfy the condition that there exists p such that Z mp =Z pi =1 or Z pm =Z mi =1, which indicates that there are other fault points in the power distribution line; if there is no m satisfying Z mm=1, or there exists m satisfying Z mm =1 and Z mi =1, or there exists m satisfying Z mm =1 and there exists p such that Z mp =Z pi =1 or Z pm =Z mi =1, then the fault point found in step S3.3 is the unique fault point.

[0011] Preferably, the value of the corresponding element in the N-dimensional fault information matrix is ​​set as follows: when the FTU protection is started and the direction is determined to be positive, the node element corresponding to the N-dimensional fault information matrix is ​​1; otherwise, it is 0.

[0012] Preferably, in step S2, the power system is judged to be faulty based on the activation of the protection device on the outgoing side of the line or the activation or operation of any FTU protection on the line.

[0013] As a preferred approach, all pole-mounted switches on the power distribution line are numbered according to the power flow direction, and an N-dimensional network topology matrix is ​​generated based on the number of switches N.

[0014] Preferably, in a multi-grid power supply mode, the power flow direction is assumed to be the positive direction of the feeder, assuming that there is only one power source.

[0015] Preferably, in step S3, the fault information includes the protection activation information of the FTU and the fault direction information determined by the FTU.

[0016] Preferably, step S1 includes: power system fault types include phase-to-phase short-circuit faults and single-phase-to-ground short-circuit faults.

[0017] Therefore, the present invention has the following beneficial effects: 1. By storing the network topology of power distribution lines in matrix form, when a fault occurs in a power distribution line, the fault direction information identified by each terminal on the line is collected, and the location of the fault is determined by combining this information with the system topology before the fault. This allows for adaptive adaptation to changes in the power distribution line topology, enabling rapid and accurate location of all fault points when a fault occurs. This provides an accurate basis for further fault isolation and power restoration, improving the reliability of the system's power supply.

[0018] 2. During the normal operation of the power distribution line, the changes in the power network topology are monitored in real time. When the power system topology changes, the fault discrimination matrix can be adaptively adjusted to meet the actual needs of the complex architecture of the power distribution line with multiple segments and branches, as well as the frequent addition of nodes or branches.

[0019] 3. When two or more faults occur simultaneously on the power distribution line, multiple faults can be accurately identified and located at the same time, avoiding the harm caused by inaccurate fault location or insufficient fault point identification. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating the overall steps of the power distribution line fault location method based on adaptive relation matrix in this invention.

[0021] Figure 2 This is a schematic diagram of the fault location process for power distribution lines in this invention.

[0022] Figure 3 This is a schematic diagram of the power distribution line architecture in Example 2. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Example 1: In recent years, with the development of smart grid technology, fault detection and location methods based on smart terminals have gradually attracted attention. These methods utilize smart sensors and data communication technologies to achieve real-time monitoring of the operating status of power distribution lines and rapid transmission of fault information.

[0024] These methods have improved the accuracy and speed of fault location to some extent, but they still have some shortcomings. For example, electrical quantity characteristic analysis methods are susceptible to load changes and environmental factors, waveform signal analysis methods have high requirements for data acquisition equipment, and topology analysis methods have limited location accuracy in complex networks and are not suitable for situations with topology changes, i.e., the topology matrix needs to be manually updated.

[0025] This embodiment provides a method for locating power distribution line faults based on an adaptive relation matrix. The purpose is to store the network topology of the power distribution line in matrix form, and when a fault occurs in the power distribution line, collect the fault direction information identified by each terminal on the line, and combine it with the system topology before the fault to determine the location of the fault.

[0026] Specifically, such as Figure 1 As shown, a fault location method for distribution lines based on an adaptive relation matrix is ​​described. The operation process is as follows: Step 1, construct an N-dimensional network topology matrix based on the number of switches in the distribution line; Step 2, monitor the power system in real time for faults. If a fault occurs, proceed to Step 3; otherwise, proceed to Step 4; Step 3, obtain fault information and use the fault location method to determine the location of the fault; Step 4, if a change in the power system topology is detected, return to Step 1 for adaptive adjustment of the topology; otherwise, return to Step 2.

[0027] By applying the above methods, we can adapt to changes in the topology of power distribution lines and quickly and accurately locate all fault points when a line fault occurs. This provides an accurate basis for further fault isolation and power restoration, thereby improving the power supply reliability of the power system.

[0028] The following specific examples further illustrate the technical solution and effects of the present invention. The examples below are explanations of the present invention, but the present invention is not limited to the following examples.

[0029] Step 1: Construct an N-dimensional network topology matrix based on the number of switches on the power distribution lines.

[0030] Analyzing the structure of a distribution network reveals three common types: tree-like networks, radiating networks, and ring networks operating in an open-loop state. Regardless of the specific structure, a distribution network consists of distribution feeders, switches, and distribution transformers. Therefore, based on graph theory definitions, the composition of a distribution network can be simplified by representing it as a matrix. A switch can be considered a vertex, and distribution lines, transformers, and other components can be considered edges. A matrix with corresponding dimensions is generated based on the number of vertices, with vertices associated with edges marked as 1 and all other values ​​marked as 0.

[0031] In this embodiment, for the selected power distribution line, all pole-mounted switches on the line are numbered according to the power flow direction, and an N*N dimensional network topology matrix D is generated based on the number of switches N.

[0032] The "current flow direction" can be the actual current flow direction in the distribution network or an assumed current direction. The specific direction definition method is as follows: For a single-source power supply network, the positive direction of the feeder is the power outflow direction of the power supply line, that is, the positive direction is from the bus to the line; In a multi-network power supply mode, it must first be assumed that there is only one power supply, and the assumed power outflow direction from the power supply to the distribution network is the positive direction of the feeder.

[0033] Step 2: Monitor the power system in real time for any faults. If a fault occurs, proceed to Step 3; otherwise, proceed to Step 4.

[0034] "Power system fault" refers to a fault occurring at any point along the entire distribution line. Fault types include, but are not limited to, phase-to-phase short-circuit faults and single-phase-to-ground short-circuit faults. The determination is based on the activation of the protection device on the outgoing line side or the activation or operation of any FTU protection unit on the line. An FTU, or distribution switch monitoring terminal, has remote control, telemetry, remote signaling, and fault detection functions. It can communicate with the distribution automation master station, providing information on the distribution system's operating status and various parameters, as well as information required for monitoring and control. This includes switch status, power parameters, phase-to-phase faults, ground faults, and parameters during faults. It also executes commands issued by the distribution master station to adjust and control the distribution equipment, achieving functions such as fault location, fault isolation, and rapid restoration of power to non-faulty areas.

[0035] Step 3: Obtain fault information and use fault location methods to determine the location of the fault.

[0036] The system collects fault information uploaded by FTUs at each node on the distribution line, determines the location of the fault based on the fault location method, and outputs the location result. The "fault information" includes, but is not limited to, FTU protection activation information and fault direction information determined by the FTU.

[0037] Specifically, in this embodiment, as Figure 2 As shown, the fault location method includes the following steps: Step (1): Each terminal on the power distribution line is subjected to fault direction determination. Based on the determination result, an N-dimensional fault information matrix T is generated, and then the process proceeds to step (2).

[0038] For an N-dimensional fault information matrix T, the corresponding elements in the matrix are set as follows: when the FTU protection is started and the direction is determined to be positive, the node element corresponding to the fault information matrix T is "1"; otherwise, the node element corresponding to the fault information matrix T is "0".

[0039] Step (2): Add the network topology matrix D from the first step to the N-dimensional fault information matrix from the first step (1) to obtain the fault location discrimination matrix Z, Z = D + T, and then proceed to step (3).

[0040] Step (3): Locate the fault point based on the element values ​​in the fault location discrimination matrix Z.

[0041] Specifically, this manifests as follows: Find the fault location discrimination matrix Z that satisfies Z ii =1, the maximum value of i, if for any j (j≠i) Z ij =0, that is, all elements in the i-th row of the fault location discrimination matrix Z except for the i-th column are 0, then the terminal feeder segment of node i is determined to be faulty; If there exists a unique j (j≠i) satisfying Z ij=1, that is, all elements in the i-th row of the matrix except for the i-th and j-th columns are 0, then the interval between nodes i and j is determined to be the fault interval; If there exist j (j≠i) and k (k≠i and k≠j) satisfying Z ij =1,Z ik If the value is 1, then the section between nodes i, j, and k is considered a faulty section.

[0042] Based on the above judgment results, the first fault section is output, and the process proceeds to step (4).

[0043] Step (4): Determine whether the fault point found in step (3) is a unique fault point. If it is a unique fault point, output the location of the fault point and end the current fault location judgment. If it is not a unique fault point, refer to step (3) to find and output the location of other fault points, and end the current fault location judgment.

[0044] The method for finding other fault points in step (4) above is as follows: For the fault points found in step (3) that satisfy Z ii =1, the maximum value of i, if there exists m (m≠i) satisfying Z mm =1, and does not satisfy any of the following conditions: Condition 1: Z mi =1; Condition 2: There exists p such that Z mp =Z pi =1 or Z pm =Z mi =1.

[0045] Then it is determined that there are other fault points in the line. Replacing i with m in step (3) will find the location of the second fault point, and so on, to find the locations of other fault points. Specifically: Find the matrix Z that satisfies Z mm =1, the maximum value m (m≠1), if for any j (j≠m) Z mj =0, then the feeder segment at the end of node m is faulty; if there exists a unique j (j≠m) satisfying Z mj =1, then the interval between nodes m and j is determined to be a fault zone; if there exist j (j≠m) and k (k≠m and k≠j) satisfying Z mj =1,Z mk If the value is 1, then the section between nodes m, j, and k is determined to be a faulty section.

[0046] If there is no m (m≠i) satisfying Z mm =1, or there exists m (m≠i) satisfying Z mm =1 but Z mi =1, or there exists m (m≠i) satisfying Z mm =1, but there exists p such that Z mp=Z pi =1 or Z pm =Z mi =1 (If there is no m (m≠i) satisfying Z) mm =1 or there exists m (m≠i) satisfying Z mm =1 If both conditions one and two are met, then the fault point found in step (3) is the only fault point.

[0047] Step 4: Detect changes in the system topology. If a change in the power system topology is detected, return to Step 1 to perform adaptive adjustment of the topology and regenerate the network topology matrix; otherwise, return to Step 2 to continue determining whether a fault has occurred.

[0048] The power distribution line fault location method based on adaptive relation matrix provided in this embodiment has the following advantages: 1. It can monitor changes in the distribution network topology in real time during the normal operation of the power system. When the system topology changes, it can adaptively adjust the fault discrimination matrix to meet the actual needs of complex architectures with multiple segments and branches of distribution lines and frequent addition of nodes or branches.

[0049] 2. When two or more faults occur simultaneously on the power distribution line, multiple faults can be accurately identified and located at the same time, avoiding the harm caused by inaccurate fault location or insufficient fault point identification.

[0050] Example 2: This embodiment provides a method for fault location of power distribution lines based on an adaptive relation matrix, and the method is applied to a specific application scenario.

[0051] In this embodiment, the power distribution line architecture is as follows: Figure 3 As shown, there are 8 pole-mounted switches, namely pole-mounted switch QF1, pole-mounted switch QF2, pole-mounted switch QF3, pole-mounted switch QF4, pole-mounted switch QF5, pole-mounted switch QF6, pole-mounted switch QF7 and pole-mounted switch QF8. Pole-mounted switch QF1 is connected to a 10kV power supply. Pole-mounted switches QF2 and QF5 are directly connected to pole-mounted switch QF1. Pole-mounted switches QF3 and QF4 are connected to pole-mounted switch QF2. Pole-mounted switches QF6 and QF8 are connected to pole-mounted switch QF5. Pole-mounted switch QF7 is connected to pole-mounted switch QF6.

[0052] Specifically, for the above power distribution line architecture: a line protection device is connected to the pole-mounted switch on the outgoing side of the power distribution line. Each pole-mounted switch on the power distribution line is equipped with a feeder terminal. When a fault occurs, each feeder terminal independently determines the fault direction and transmits the determination result to the outgoing side line protection device. The line protection device integrates the power distribution line fault location method based on the adaptive relation matrix provided in this embodiment, and completes the fault location by combining the fault direction determination result sent by the feeder terminal. According to the fault location result, a trip command is sent to trip the feeder terminals on both sides of the fault to complete the fault isolation.

[0053] according to Figure 3 The specific steps for fault identification using the power distribution line fault location method based on the adaptive relation matrix provided in Example 1, as shown in the power distribution line architecture, are as follows: Step 1: For the selected power distribution line, number all pole-mounted switches on the line according to the power flow direction, and generate an N*N dimensional network topology matrix D based on the number of switches N.

[0054] In this embodiment, there are a total of 8 pole-mounted switches in the wiring line, numbered from QF1 to QF8. Therefore, the network topology matrix D generated in this embodiment is an 8*8 matrix.

[0055] Specifically, the pole-mounted switch is regarded as a vertex of the power distribution network, and the power distribution lines, power distribution transformers and other components are regarded as edges. A matrix with corresponding dimensions is generated according to the number of vertices. The vertices associated with the edges are marked as 1 in the matrix, and the rest are marked as 0.

[0056] According to such Figure 3 The wiring diagram shown below, based on the positive current direction, illustrates the connection relationships between the pole-mounted switches, as shown in the table below: QF1 QF2 QF3 QF4 QF5 QF6 QF7 QF8 QF1 0 1 0 0 1 0 0 0 QF2 0 0 1 1 0 0 0 0 QF3 0 0 0 0 0 0 0 0 QF4 0 0 0 0 0 0 0 0 QF5 0 0 0 0 0 1 0 1 QF6 0 0 0 0 0 0 1 0 QF7 0 0 0 0 0 0 0 0 QF8 0 0 0 0 0 0 0 0 Therefore, based on the table above, the network topology matrix D generated by the power distribution line architecture is:

[0057] Step 2: Monitor the power system in real time to see if any faults occur.

[0058] like Figure 3 As shown, the power system has a fault in this embodiment, so step three is executed directly.

[0059] Step 3: Collect fault information uploaded by each node FTU, determine the location of the fault according to the fault location method, and output the location result.

[0060] according to Figure 3 The power distribution line diagram shown indicates that the fault occurred at the end of pole-mounted switch QF8 and between pole-mounted switches QF6 and QF7.

[0061] Consider pole-mounted switch QF1 as node 1, and pole-mounted switches QF2 through QF8 as nodes 1 through 8 respectively. When a fault occurs at the end of pole-mounted switch QF8 (i.e., node 8, and the same applies to subsequent pole-mounted switches), or at pole-mounted switches QF6 (node ​​6) and QF7 (node ​​7)... Figure 3 (As already marked), the nodes with the fault current in the positive direction are node 1, node 5, node 6 and node 8.

[0062] Figure 3 The power distribution line shown has 8 nodes, therefore the fault information matrix has 8*8 elements, representing nodes 1 to 8 respectively. Elements corresponding to nodes with positive fault current are marked as "1", otherwise marked as "0". Therefore, the resulting fault information matrix T is: T=diag[1 0 0 0 0 1 1 0 1].

[0063] Add the network topology matrix D from step one to the fault information matrix T to obtain the fault discrimination matrix Z:

[0064] The following judgment method is used: Find the fault location discrimination matrix Z that satisfies Z ii The maximum value of i = 1 is found to be 8 based on the fault discrimination matrix Z above.

[0065] If for any j (j≠8) Z 8j =0, meaning that all elements in the 8th row of the fault location discrimination matrix Z are 0 except for the 8th column, then the feeder segment at the end of node 8 is determined to be faulty. The fault discrimination matrix Z above satisfies the condition that all elements in the 8th row are 0 except for the 8th column; therefore, the feeder segment at the end of node 8 is determined to be faulty, and this is the first fault point.

[0066] If there exists a unique j (j≠8) satisfying Z 8j =1, meaning that all elements in the 8th row of the matrix except for the 8th and jth columns are 0, then the area between nodes 8 and j is determined to be a fault interval. However, there is no unique j in the fault location discrimination matrix Z that satisfies the aforementioned condition, therefore there is no fault interval.

[0067] If there exist j (j≠8) and k (k≠8 and k≠j) satisfying Z 8j =1,Z 8k If the value is 1, then the area between nodes i, j, and k is determined to be a fault segment. However, j and k do not exist in the fault location discrimination matrix Z, which satisfies the aforementioned condition because there is no fault segment.

[0068] Based on the above steps, the fault point is output as: the feeder segment at the end of node 8.

[0069] Next, determine whether the output fault band is the only fault point.

[0070] Specifically, it includes: For the found satisfying Z ii =1, the maximum value of i, i=8, if there exists m (m≠8) satisfying Z mm =1, and does not satisfy the following two conditions: Condition 1: Z mi =1; Condition 2: There exists p such that Z mp =Z pi =1 or Z pm =Z mi =1.

[0071] If neither of the above two conditions is met, it is determined that there are other fault points in the power distribution line.

[0072] Based on the fault location discrimination matrix Z above, there exist m=1, m=5, and m=6 that respectively satisfy Z 11 =1,Z 55 =1,Z 66 =1.

[0073] For m=1: Z 18 =0, condition one is not satisfied: Z 18 =1; but there exists P=5 that satisfies Z 15 =Z 58 =1, which satisfies condition two. Therefore, m=1 does not satisfy condition one but satisfies condition two, so m=1 is discarded.

[0074] For m=5, Z 58 =1, satisfying condition one: Z 58 =1, but there exists P=1 that satisfies Z 15 =Z 58 =1, which satisfies condition two, therefore m=5 is discarded.

[0075] For m=6: Z 68 =0, condition one is not satisfied: Z 68 =1; and there is no P satisfying Z p6 =Z 68 =1, and Z does not exist. 6p =Z p8 =1, which does not satisfy condition two. Therefore, m=6 does not satisfy both condition one and condition two. So m=6 is retained.

[0076] In summary, for the found Z ii =1, the maximum value of i, i=8, there exists m=6 (m≠8) satisfying Zmm =1, and both conditions one and two are satisfied, therefore there are other fault points in the power distribution line.

[0077] Based on the fault diagnosis method, replace i with m to find the location of the second fault point.

[0078] Specifically: Based on m=6: If for any j (j≠6) Z 6j =0, meaning that all elements in the 6th row of the fault location discrimination matrix Z except for the 6th column are 0, then the terminal feeder segment of node 6 is determined to be faulty. However, the above fault discrimination matrix Z satisfies that all elements in the 6th row except for the 6th column are 1, therefore, the terminal feeder segment of node 6 is determined to be without fault.

[0079] If there exists a unique j (j≠6) satisfying Z 6j =1, meaning that all elements in the 6th row of the matrix except for the 6th and jth columns are 0, then the fault interval between node 6 and node j is determined. Furthermore, there exists a unique condition j=7 in the fault location matrix Z that satisfies the aforementioned condition; therefore, the fault interval between node 6 and node 7 is determined.

[0080] If there exist j (j≠6) and k (k≠6 and k≠j) satisfying Z 6j =1,Z 6k If the value is 1, then the area between nodes i, j, and k is determined to be a fault segment. However, j and k do not exist in the fault location discrimination matrix Z, which satisfies the aforementioned condition because there is no fault segment.

[0081] In summary, according to the power distribution line fault location method in Example 1, the first fault point found is the feeder segment at the end of node 8, and the second fault point can be found between nodes 6 and 7. Since Z... 15 =Z 58 =1, therefore although Z 11 and Z 55 They are all equal to 1, but none of them are new fault points.

[0082] Compared with existing technologies, when the power system network topology is known and fixed, and the distribution line has only a single fault point, the distribution line fault location method based on adaptive relation matrix provided in this embodiment can quickly and accurately locate distribution line faults. Furthermore, when two or more faults occur simultaneously on the line, the fault location method of this embodiment can also accurately identify and locate multiple faults at the same time, avoiding the hazards caused by inaccurate fault location or insufficient fault point identification.

[0083] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A method for fault location in power distribution lines based on an adaptive relation matrix, characterized in that, include: S1: Construct an N-dimensional network topology matrix based on the number of switches in the power distribution lines; S2: Monitor the power system in real time to see if any faults occur. If a fault occurs, proceed to step S3; otherwise, proceed to step S4. S3: Obtain fault information and use fault location methods to determine the location of the fault; S4: If a change in the power system topology is detected, return to step S1 to perform adaptive topology adjustment; otherwise, return to step S2.

2. The method for fault location of distribution lines based on an adaptive relation matrix according to claim 1, characterized in that, The fault location method includes: S3.1: Determine the fault direction for each terminal on the power distribution line and generate an N-dimensional fault information matrix; S3.2: Add the network topology matrix and the fault information matrix to obtain the fault location discrimination matrix Z; S3.3: Based on the values ​​of the elements in the fault location discrimination matrix, determine the fault location and output the fault point; S3.4: If the fault point output in step S3.3 is the only fault point, then output the fault point and end the current fault location; otherwise, find and output other fault points.

3. The method for fault location of distribution lines based on an adaptive relation matrix according to claim 2, characterized in that, In step S3.3: Z satisfies ii The maximum value of i is equal to 1, if for any j, Z = 1. ij =0, and j≠i, then the feeder segment at the end of node i is faulty; if there exists a unique j, and j≠i, satisfying Z ij =1, then the interval between nodes i and j is determined to be a fault zone; if there exist j, k, j≠i, k≠i and k≠j, satisfying Z ij =1, Z ik If the value is 1, then the section between nodes i, j, and k is considered a faulty section.

4. The method for fault location of distribution lines based on an adaptive relation matrix according to claim 3, characterized in that, For satisfying Z ii The maximum value of i = 1, if there exists m satisfying Z mm =1, m≠i, and does not satisfy Z mi =1 and does not satisfy the condition that there exists a p such that Z mp =Z pi =1 or Z pm =Z mi =1 indicates that there are other fault points in the power distribution line; if m does not satisfy Z mm =1, or there exists m satisfying Z mm =1 and Z mi =1, or there exists m satisfying Z mm =1 and there exists p such that Z =1, ... mp =Z pi =1 or Z pm =Z mi If the value is 1, then the fault point found in step S3.3 is the only fault point.

5. A method for fault location of distribution lines based on an adaptive relation matrix according to claim 2, 3, or 4, characterized in that, In the N-dimensional fault information matrix, the value of the corresponding element is set as follows: when the FTU protection is started and the direction is determined to be positive, the node element corresponding to the N-dimensional fault information matrix is ​​1; otherwise, it is 0.

6. A method for fault location of distribution lines based on an adaptive relation matrix according to claim 2, 3, or 4, characterized in that, Based on the power flow direction, all pole-mounted switches on the power distribution line are numbered, and an N-dimensional network topology matrix is ​​generated based on the number of switches N.

7. A method for fault location of distribution lines based on an adaptive relation matrix according to claim 1, 2, 3, or 4, characterized in that, In step S2, it is determined whether the power system is faulty based on the activation of the protection device on the outgoing side of the line or the activation or operation of any FTU protection on the line.

8. The method for fault location of distribution lines based on an adaptive relation matrix according to claim 6, characterized in that, In a multi-grid power supply mode, the power flow direction is assumed to be the positive direction of the feeder, assuming that there is only one power source.

9. A method for fault location of distribution lines based on an adaptive relation matrix according to claim 1, 2, 3, or 4, characterized in that, In step S3, the fault information includes the protection activation information of the FTU and the fault direction information determined by the FTU.

10. A method for fault location of distribution lines based on an adaptive relation matrix according to claim 1, 2, 3, or 4, characterized in that, Step S1 includes: power system fault types include phase-to-phase short circuit faults and single-phase-to-ground short circuit faults.

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