Power distribution line fault location method based on wide-area traveling wave monitoring device

Abstract

The application discloses a power distribution line fault positioning method based on a wide-area traveling wave monitoring device, which comprises the following steps: S1, deploying and three-dimensionally coordinating the wide-area traveling wave monitoring device; S2, discretely dividing the whole power distribution line into a plurality of potential fault points and establishing a space coordinate model; S3, according to the line topological structure, calculating the shortest traveling wave propagation time of each potential fault point to each monitoring device, and constructing a fault positioning traveling wave criterion matrix; S4, collecting the traveling wave arrival time of the triggering device when the fault occurs, and forming a time vector; S5, performing data processing on the traveling wave arrival time information, and obtaining a relative time difference time characteristic vector; and S6, matching and calculating the time characteristic vector with the criterion matrix, and determining the fault point position. The power distribution line fault positioning method based on the wide-area traveling wave monitoring device can realize the effects of high positioning precision, fast response speed, adaptation to complex topologies and easy deployment and popularization, and significantly improves the power distribution network fault investigation efficiency and power supply reliability.

Description

Technical Field

[0001] This invention relates to the field of power system distribution line fault location technology, specifically a distribution line fault location method based on a wide-area traveling wave monitoring device. Background Technology

[0002] As a crucial link connecting power sources and end users in the power system, the rapid detection, accurate location, and timely isolation of line faults are core technical means to improve power supply reliability, reduce power outage losses, and ensure the continuity of electricity supply for residential use and industrial production. Currently, commonly used fault location methods mainly include impedance methods, fault indicator methods, and traditional traveling wave methods, but these have significant shortcomings in practical applications.

[0003] Impedance methods are easily affected by load, line parameters, and grounding resistance, resulting in large positioning errors and only enabling segment estimation. Fault indicator methods can only be used for segmental judgment, failing to pinpoint precise locations, and are prone to misjudgment under complex branch faults and low-current grounding faults. While traditional traveling wave methods offer improved accuracy, they require real-time processing of large amounts of waveform data, complex wavefront identification, and path calculation, resulting in high computational load and slow response, making it difficult to meet the needs of rapid positioning.

[0004] Meanwhile, modern power distribution networks are complex in structure, have many branches, and flexible and varied topologies. Traditional methods do not provide standardized modeling of potential fault points across the entire line area and cannot adapt to dynamic changes in topology, resulting in poor stability in scenarios with multiple branches and high-resistance grounding. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for locating power distribution line faults based on a wide-area traveling wave monitoring device.

[0006] This invention is achieved through the following technical solution: a method for locating faults in power distribution lines based on a wide-area traveling wave monitoring device, comprising the following steps:

[0007] S1. Deploy and coordinate the wide-area traveling wave monitoring device in three dimensions;

[0008] S2. Discretize the entire power distribution line into several potential fault points and establish a spatial coordinate model;

[0009] S3. Based on the line topology, calculate the shortest travel time of the traveling wave from each potential fault point to each monitoring device, and construct the fault location traveling wave criterion matrix.

[0010] S4. When a fault occurs, the arrival time of the traveling wave of the triggering device is collected to form a time vector;

[0011] S5. Process the arrival time information of the traveling wave to obtain a relative time difference time feature vector;

[0012] S6. Match the time feature vector with the criterion matrix to determine the location of the fault point.

[0013] Furthermore, the wide-area traveling wave monitoring device includes a sensor, a data acquisition module, and a communication module, used to capture traveling wave signals and record their arrival time.

[0014] In step S1, the unified spatial coordinate model includes the axial distance dimension of the line, the branch distance dimension, and the traveling wave propagation time dimension, which is used to achieve accurate coordinate calibration of the device and the fault point.

[0015] In step S2, the discretization method defines a potential fault point for each preset interval along the line, and adds potential fault points at critical electrical nodes according to the line branches and connection relationships.

[0016] In step S3, the traveling wave criterion matrix is ​​n×m dimensional, where n is the number of fault points and m is the number of devices, and supports real-time updates for line topology changes.

[0017] In step S3, if the traveling wave reaches the same device through multiple paths, the shortest propagation time is selected to construct the criterion matrix.

[0018] In step S4, the wide-area traveling wave monitoring device is equipped with a high-frequency sampling module and a traveling wave triggering unit to capture voltage or current change signals in real time.

[0019] In step S4, a satellite-synchronized clock and time synchronization protocol are used to ensure that the clock error of all devices is ≤0.1μs.

[0020] In step S5, the time vector is traversed to determine the minimum value. The minimum value is then subtracted from each element in the vector to obtain a new time feature vector.

[0021] In step S6, fault location is based on Euclidean distance as the similarity criterion, and the node corresponding to the minimum distance is the fault point.

[0022] The present invention has the following advantages:

[0023] 1. High-precision positioning: By comparing traveling wave signals and criterion matrices, positioning accuracy is significantly improved.

[0024] 2. Fast response: The criterion matrix can be generated offline, reducing the demand for real-time computing resources; the data processing logic is optimized, the computational complexity is reduced, and the response speed is improved.

[0025] 3. Adaptable to complex networks: The discretization of potential fault points and the real-time updating of the criterion matrix with topology changes effectively address the fault location requirements of complex power distribution networks.

[0026] 4. Easy to implement and promote: The method has a clear logic, is easy to deploy in existing wide-area monitoring systems, has low deployment costs, is compatible with existing power distribution automation systems, and is suitable for large-scale promotion and application. Attached Figure Description

[0027] The accompanying drawings, as part of this invention, are provided to further illustrate the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention, but do not constitute an undue limitation thereof. Clearly, the drawings described below are merely some embodiments, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0028] In the attached diagram:

[0029] Figure 1 This is a diagram showing the distribution network transmission line topology and monitoring device deployment of the present invention.

[0030] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0032] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0034] The method for locating power line faults based on a wide-area traveling wave monitoring device includes the following steps:

[0035] S1. Deploy and coordinate the wide-area traveling wave monitoring device in three dimensions;

[0036] The unified spatial coordinate model includes the axial distance dimension of the line, the branch distance dimension, and the time dimension, which is used to achieve accurate coordinate calibration of the device and the fault point.

[0037] Specifically, a coordinate system (x, y, t) is established based on the power lines:

[0038] x represents the distance from any point on the main line to the beginning, in meters (m).

[0039] y represents the distance from any point on the branch to the corresponding branch point, in meters (m).

[0040] t represents time, used to mark the absolute time when the traveling wave arrives at the monitoring device, in μs.

[0041] Suppose there are m wide-area traveling wave monitoring devices deployed in the power distribution line, numbered D1, D2, ..., D... m The spatial position of each device is mapped to a coordinate system (x, y, t), such as:

[0042] D1(x) d1 y d1 , t d1 );

[0043] Wherein, time t dm Represents the coordinates of propagation time characteristics.

[0044] The wide-area traveling wave monitoring device includes sensors, a data acquisition module, and a communication module, used to capture traveling wave signals and record their arrival times. Specifically, this invention employs a voltage / current sensor, a high-frequency data acquisition module, a fault triggering unit, a satellite synchronization clock module, and a communication module, which can detect sudden changes in line voltage or current in real time, accurately capture the traveling wave front, and record the arrival time.

[0045] S2. Discretize the entire power distribution line into several potential fault points and establish a spatial coordinate model;

[0046] The entire distribution line, including the main line and all branches, is discretized into n potential fault points, denoted as N1, N2, ..., N. n Each potential fault point corresponds to a coordinate in the coordinate system established in step 1:

[0047] N1(x1,y1,t1), N2(x2,y2,t2),…,N n (x) n y n , t n );

[0048] Wherein, time t n This represents the theoretical propagation time characteristic parameter of the corresponding candidate fault point.

[0049] The discretization method is as follows:

[0050] A potential fault point is defined at intervals Δd along the line. Δd is dynamically selected based on the traveling wave propagation speed and clock synchronization accuracy, with a typical value of 100m, balancing meter-level positioning accuracy and computational efficiency.

[0051] Based on the branching and connection relationships of the lines, potential fault points are added at key electrical locations such as sectionalizing switches, branch points, T-junctions, cable joints, and load nodes.

[0052] All discrete points are incorporated into a unified coordinate model, covering the locations where faults may occur along the entire route.

[0053] S3. Based on the line topology, calculate the shortest travel time of the traveling wave from each potential fault point to each monitoring device, and construct the fault location traveling wave criterion matrix.

[0054] S31. Calculate the shortest propagation time of the traveling wave.

[0055] For each potential failure point N i (i=1, 2, ..., n), calculate the fault traveling wave from N i Transmitted to each monitoring device D j Time t for (j=1, 2, ..., m) ij .

[0056] Based on the fundamental wave propagation relationship:

[0057]

[0058] Substitute the project path length into:

[0059]

[0060] get:

[0061]

[0062] Where v is the traveling wave velocity, in km / s;

[0063] If a traveling wave reaches the same device through multiple paths, the shortest propagation time is selected to construct a criterion matrix to avoid multi-path interference.

[0064] S32. Generate an n×m dimensional criterion matrix T

[0065] Matrix element t ij Indicates the potential failure point N i To monitoring device D jThe propagation time of traveling wave theory, all t ij Together they constitute the traveling wave positioning criterion matrix T.

[0066]

[0067] The traveling wave criterion matrix is ​​n×m dimensional, where n is the total number of potential fault points after the power distribution line is discretized, and m is the total number of wide-area traveling wave monitoring devices deployed on site. Each row of the matrix corresponds to the traveling wave propagation time vector of a potential fault point, and each column corresponds to the traveling wave arrival time vector of a monitoring device.

[0068] When the line topology changes (such as switching on or off), the shortest path is recalculated and the criterion matrix is ​​updated to ensure that the matrix is ​​consistent with the current network structure.

[0069] S4. When a fault occurs, the arrival time of the traveling wave of the triggering device is collected to form a time vector;

[0070] S41, Wide-area traveling wave monitoring device D j Equipped with a high-frequency sampling module (sampling rate ≥ 1MHz) and a traveling wave trigger unit, it captures voltage or current surge signals in real time; when the signal amplitude exceeds the threshold (5%-10% of the line's rated voltage) or the waveform steepness ( When the value exceeds the set value, data recording is triggered.

[0071] S42. Use satellite-synchronized clocks and time synchronization protocols (such as IEEE1588PTP or IRIG-B) to ensure that the clock error of all devices is ≤0.1μs.

[0072] S43. When a fault occurs in a power distribution line, assume the actual fault point is located at N(x, y, t). The traveling wave signal generated by the fault propagates to the monitoring device, triggering k devices (k≤m), recording their traveling wave arrival times and forming a time vector:

[0073] A=[t d1 ,t d2 ,..,t dm ].

[0074] The time of untriggered devices is not included in subsequent calculations (it is considered invalid data and denoted as t in the time vector). df ), to avoid introducing noise.

[0075] S5. Process the arrival time information of the traveling wave to obtain a relative time difference time feature vector;

[0076] S51. Traverse the time vector A to determine the minimum value:

[0077] t dmin =min(t) d1,t d2 ,..,t dm ),

[0078] S52. Subtract the minimum value from each element of the vector to obtain the new time vector B:

[0079] B=[t d1 -t dmin ,t d2 -t dmin ,..,t dm -t dmin ].

[0080] S6. Match the time feature vector with the criterion matrix to determine the location of the fault point.

[0081] S61. Compare the time vector B with each row of the standard criterion matrix and calculate the similarity.

[0082] Using Euclidean distance as the similarity metric, the similarity between the time vector B and the i-th row vector T of the criterion matrix T is calculated. i =[t i1 ,t i2 ,..,t im The distance d i :

[0083] ;

[0084] Here, j only traverses the triggering device.

[0085] S62. Traverse all potential fault points and select the node N corresponding to the minimum distance. k As a point of failure:

[0086] .

[0087] S63. Output the coordinates of the fault point, the line location and distance information to complete the location.

[0088] The following section uses a 10kV multi-branch distribution line as a typical application scenario, and provides a detailed step-by-step description of the distribution line fault location method based on a wide-area traveling wave monitoring device according to the present invention through specific embodiments:

[0089] S1. Line Parameters and Settings

[0090] Line: 10kV overhead distribution line, 4km main line + 1 2km branch line;

[0091] Traveling wave velocity: v = 296 m / μs

[0092] Discrete interval: Δd = 100m;

[0093] Monitoring devices: m=3: D1: Main line start (x=0, y=0); D2: Main line end (x=4000, y=0); D3: Branch line end (x=1500, y=2000);

[0094] Potential failure points: n=61 (41 main lines + 20 branch lines);

[0095] Coordinate system: x: axial distance of the main line (m); y: distance from the branch line to the branch point (m); t: propagation time (μs);

[0096] S2. List of Potential Failure Points

[0097] Main line (y=0): N1(0,0), N2(100,0),...,N 41 (4000,0);

[0098] Branch (x=1500): N 42 (1500, 100), N 43 (1500,200),...,N 61 (1500,2000);

[0099] S3. Criterion matrix T (30×3)

[0100] In matrix T, each row corresponds to an N. i Theoretical propagation time [t] i1 ,t i2 ,t i3 ], Calculation formula (per element): t ij =(|x i -x dj |+|y i -y dj |) / 296.

[0101]

[0102] S4. Fault Simulation

[0103] Actual fault location: Main line x=1220m, y=0 (close to N) 13 (x=1200).

[0104] Acquisition time vector: A = [4.122, 9.392, 7.703] μs;

[0105] S5. Time Eigenvector B

[0106] t dmin =min(A)=4.122μs;

[0107] B=[0,5.270,3.581];

[0108] S6. Matching and Positioning

[0109] The similarity between each row and B is calculated using Euclidean distance, and the point with the smallest similarity corresponds to the fault point. Key calculation processes are shown below (the closest points are listed below):

[0110] N 13 (1200,0): d 13 = ≈0.116

[0111] N 14 (1300,0): d 13 ≈0.468; N 12 (1100,0): d 12 ≈0.701; N 15 (1400,0): d 15 ≈1.053

[0112] =13;

[0113] Result: Matched N 13 (x=1200, y=0), positioning successful, error 20m, meeting the patented meter-level accuracy requirements.

[0114] The present invention relates to a power distribution line fault location method based on a wide-area traveling wave monitoring device. By using the coordinate system of the wide-area traveling wave monitoring device and the global discretization of potential fault points in the power distribution line, the traveling wave criterion matrix is ​​pre-calculated and constructed. When a fault occurs, the arrival time of the traveling wave is collected with high precision and processed with relative time difference. The method uses Euclidean distance for rapid matching and location, achieving high positioning accuracy, fast response speed, adaptability to complex topologies, and easy deployment and promotion. This method can significantly improve the efficiency of power distribution network fault diagnosis and power supply reliability.

[0115] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0116] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features found in other embodiments but not others, combinations of features from different embodiments are also within the scope of protection of this invention and form different embodiments. For example, in the embodiments described above, those skilled in the art can use them in combination based on known technical solutions and the technical problems to be solved by this application.

[0117] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for locating faults in power distribution lines based on a wide-area traveling wave monitoring device, characterized in that: Includes the following steps: S1. Deploy and coordinate the wide-area traveling wave monitoring device in three dimensions; S2. Discretize the entire power distribution line into several potential fault points and establish a spatial coordinate model; S3. Based on the line topology, calculate the shortest travel time of the traveling wave from each potential fault point to each monitoring device, and construct the fault location traveling wave criterion matrix. S4. When a fault occurs, the arrival time of the traveling wave of the triggering device is collected to form a time vector; S5. Process the arrival time information of the traveling wave to obtain a relative time difference time feature vector; S6. Match the time feature vector with the criterion matrix to determine the location of the fault point.

2. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: The wide-area traveling wave monitoring device includes sensors, a data acquisition module, and a communication module, used to capture traveling wave signals and record their arrival time.

3. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S1, the unified spatial coordinate model includes the axial distance dimension of the line, the branch distance dimension, and the traveling wave propagation time dimension, which is used to achieve accurate coordinate calibration of the device and the fault point.

4. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S2, the discretization method defines a potential fault point for each preset interval along the line, and adds potential fault points at critical electrical nodes according to the line branches and connection relationships.

5. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S3, the traveling wave criterion matrix is ​​n×m dimensional, where n is the number of fault points and m is the number of devices, and supports real-time updates for line topology changes.

6. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S3, if the traveling wave reaches the same device through multiple paths, the shortest propagation time is selected to construct the criterion matrix.

7. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S4, the wide-area traveling wave monitoring device is equipped with a high-frequency sampling module and a traveling wave triggering unit to capture voltage or current change signals in real time.

8. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S4, a satellite-synchronized clock and time synchronization protocol are used to ensure that the clock error of all devices is ≤0.1μs.

9. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S5, the time vector is traversed to determine the minimum value. The minimum value is then subtracted from each element in the vector to obtain a new time feature vector.

10. The method for locating power line faults based on a wide-area traveling wave monitoring device as described in claim 1, characterized in that: In step S6, fault location is based on Euclidean distance as the similarity criterion, and the node corresponding to the minimum distance is the fault point.

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