Power distribution network single-phase ground fault section positioning method, device, equipment and medium

Abstract

The application discloses a power distribution network single-phase grounding fault section positioning method, device, equipment and medium, and relates to the technical field of power distribution network fault positioning. The method comprises the following steps: acquiring transient characteristic data of multiple measuring points of a fault power distribution network at the time of fault occurrence, and dividing the fault power distribution network into multiple candidate sections according to the topological structure of the fault power distribution network; constructing boundary mutation features according to the transient characteristic data of adjacent measuring points of each candidate section; constructing internal consistency features according to the transient characteristic data of internal measuring points of each candidate section; constructing topological constraint features according to the boundary mutation features and the internal consistency features of each candidate section in combination with the topological structure; and positioning a target fault section in the multiple candidate sections in combination with the boundary mutation features, the internal consistency features and the topological constraint features of each candidate section. Through implementation of the application, the accuracy of single-phase grounding fault section positioning in a medium / low-voltage power distribution system can be improved.

Description

Technical Field

[0001] This application relates to the field of distribution network fault location technology, and in particular to a method, device, equipment and medium for locating single-phase grounding fault sections in a distribution network. Background Technology

[0002] Single-phase grounding faults are among the most common fault types in medium- and low-voltage distribution systems. Because medium- and low-voltage distribution networks typically operate with a neutral point that is not effectively grounded, the fault current after a single-phase grounding fault is weak. Furthermore, the transient process of the fault is affected by factors such as transition resistance, line-to-ground capacitance, or the connection of distributed power sources, making the fault characteristics complex and uncertain, thus making it difficult to locate the fault section and handle the fault. Therefore, it is necessary to study the location of single-phase grounding fault sections in medium- and low-voltage distribution systems to improve its accuracy and reliability.

[0003] Existing methods for locating single-phase grounding fault sections in medium and low voltage power distribution systems mainly include: (1) methods based on transient feature discrimination, which use the short-term changes in the power distribution network characteristics after the fault occurs to determine the section. These methods are highly dependent on specific frequency bands / models / thresholds. When the fault conditions change, their feature stability is insufficient, which can easily lead to misjudgment or missed judgment; (2) location methods based on multi-feature fusion, which combine multiple steady-state or transient indicators to improve the reliability of section location. However, these methods often focus on the fault characteristics of a single measuring point or a single section boundary, which is not suitable for the fault location of a single-phase grounding fault. The sudden change characteristics at the boundary of the fault section and the lack of attention to the consistency among multiple measuring points within the section lead to questionable accuracy in locating the actual fault section; (3) Combining network topology or fault propagation laws, the fault section is screened and located by further utilizing topology-related features such as feeder segmentation, upstream and downstream relationships and branch relationships. However, topology information is usually used as an auxiliary condition for post-fault screening and location, and the role of topology information in the short time after the fault occurs is not considered. When there are omissions in post-fault data collection, the accuracy of post-fault section screening and location based on topology information is obviously insufficient. Obviously, the current methods for locating single-phase ground faults in medium and low voltage power distribution systems have varying degrees of location defects. Therefore, how to improve the accuracy of single-phase ground fault location in medium and low voltage power distribution systems is still an urgent problem to be solved by existing technologies. Summary of the Invention

[0004] This application provides a method, device, equipment, and medium for locating single-phase grounding fault sections in a power distribution network, in order to solve the technical problem of insufficient accuracy in locating single-phase grounding fault sections in existing medium and low voltage power distribution systems.

[0005] According to a first aspect of the embodiments of this application, a method for locating a single-phase ground fault section in a distribution network is provided, comprising: The transient characteristic data of multiple measuring points in the faulted distribution network at the time of the fault occurrence are obtained, and the faulted distribution network is divided into multiple candidate segments according to the topology of the faulted distribution network. Based on the transient feature data of the neighboring measuring points corresponding to each candidate segment, the boundary abrupt change feature of each candidate segment is constructed; wherein, the neighboring measuring point is the measuring point that is closest to both ends of the corresponding candidate segment outside the corresponding candidate segment among the plurality of measuring points; Based on the transient feature data of the internal measurement points corresponding to each candidate segment, an internal consistency feature is constructed for each candidate segment; wherein, the internal measurement points are all the measurement points within the corresponding candidate segment among the plurality of measurement points; Based on the boundary abrupt change characteristics and internal consistency characteristics of each candidate segment, and in conjunction with the topology, the topological constraint characteristics of each candidate segment are constructed. By combining the boundary abrupt change characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate segment, the target fault segment of the faulty distribution network is located from the multiple candidate segments.

[0006] This application first obtains transient characteristic data of multiple measuring points in a faulty distribution network at the time of the fault, and divides the faulty distribution network into multiple candidate segments according to the topology of the faulty distribution network. Then, in each candidate segment, boundary abrupt change features are constructed based on the transient characteristic data of the corresponding neighboring measuring points, internal consistency features are constructed based on the transient characteristic data of the corresponding internal measuring points, and topological constraint features are constructed based on the boundary abrupt change features, internal consistency features, and topology. Finally, the target fault segment is located from the multiple candidate segments. Compared with the prior art, this application utilizes the transient characteristic data of multiple measuring points in the faulty distribution network at the time of the fault, and constructs boundary abrupt change features associated with the abrupt change characteristics at the boundary of the fault segment, internal consistency features associated with the consistency among multiple measuring points within the fault segment, and topological constraint features associated with the topology information of the faulty distribution network. This comprehensively covers all types of fault characteristics in the fault segment, and then comprehensively applies the above features to locate the fault segment, which can improve the accuracy of locating single-phase grounding fault segments in the faulty distribution network.

[0007] In some embodiments of this application, acquiring transient characteristic data of multiple measuring points in the faulted distribution network at the time of the fault specifically includes: Based on a preset event criterion function, a fault occurrence determination is made for each measuring point in the faulty distribution network, and the local event reference point corresponding to each measuring point when the fault occurs is determined. The transient feature components of each measuring point within multiple preset time windows of the corresponding local event reference point are obtained to obtain the original transient feature data of each measuring point when the fault occurs. The original transient feature data of each measuring point is removed from the base and normalized to obtain the transient feature data of each measuring point.

[0008] This application first uses an event criterion function to determine the local event reference point corresponding to each measuring point in the faulty distribution network at the time of the fault occurrence. Then, it obtains the transient feature components within multiple preset time windows to obtain the original transient feature data. Then, it obtains the transient feature data of each measuring point by removing the base value and normalizing. By using the event criterion function to determine the local event reference point for each measuring point, it considers the actual time delay of the fault propagation in the distribution network and the actual reaction delay of each measuring point to the fault. This avoids the situation where uniformly defining the event reference point would cause the obtained transient feature data to not correspond to the actual fault period, thereby avoiding the distortion of transient feature data, ensuring the correctness of transient feature data, and providing a correct data basis for locating single-phase grounding fault sections in the faulty distribution network.

[0009] In some embodiments of this application, the neighboring measuring points include upstream neighboring measuring points and downstream neighboring measuring points; the step of constructing the boundary abrupt change features of each candidate segment based on the transient feature data of the neighboring measuring points corresponding to each candidate segment specifically includes: Acquire upstream transient characteristic data of upstream neighboring measuring points and downstream transient characteristic data of downstream neighboring measuring points corresponding to each candidate segment, and construct polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment in sequence based on the upstream transient characteristic data and the downstream transient characteristic data. Based on the polarity transition index, energy mutation index, morphological difference index, and decay gradient index corresponding to each candidate segment, the boundary mutation characteristics of each candidate segment are obtained.

[0010] This application first obtains upstream transient characteristic data from upstream neighboring measuring points and downstream transient characteristic data from downstream neighboring measuring points for each candidate section. Then, based on the upstream and downstream transient characteristic data, it sequentially constructs polarity transition index, energy mutation index, morphological difference index, and attenuation gradient index for each candidate section, thereby obtaining the boundary mutation characteristics of each candidate section. Compared with the prior art, by considering the various indices associated with the mutation characteristics at the boundary of the fault section, the boundary mutation characteristics can be obtained, which can cover the data characteristics of fault-related boundary mutations in the fault section. This provides a data foundation for subsequent comprehensive application of multiple fault-related type characteristics for location, thereby improving the accuracy of single-phase grounding fault section location in the faulty distribution network.

[0011] In some embodiments of this application, constructing the internal consistency features of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment specifically includes: Based on the transient characteristic data of the internal measurement points corresponding to each candidate segment, the trend consistency index, polarity consistency index, and attenuation interpretability index of each candidate segment are constructed in sequence. The internal consistency characteristics of each candidate segment are obtained based on the trend consistency index, polarity consistency index, and decay interpretability index.

[0012] This application first constructs corresponding trend consistency index, polarity consistency index, and attenuation interpretability index based on the transient characteristic data of the internal measuring points of each candidate section, thereby obtaining the internal consistency characteristics of each candidate section. Compared with the prior art, by considering the various indices of the consistency correlation between multiple measuring points within the fault section regarding the fault, the internal consistency characteristics can be obtained. This can cover the data characteristics between multiple internal measuring points related to the fault in the fault section, thereby providing a data foundation for subsequent comprehensive application of various fault-related type features for location, thus improving the accuracy of single-phase grounding fault section location in the faulty distribution network.

[0013] In some embodiments of this application, the step of constructing the topological constraint features of each candidate segment based on its boundary abruptness and internal consistency features, combined with the topological structure, specifically includes: Based on the topology, the upstream path set, downstream non-faulty branch set, and adjacent branch node set of each candidate segment are obtained; Based on the boundary abrupt change characteristics of each candidate segment and combined with the corresponding upstream path set, an upstream continuity index is constructed for each candidate segment. Based on the internal consistency characteristics of each candidate segment and combined with the corresponding set of downstream non-faulty branches, a downstream rejection index is constructed for each candidate segment. Based on the boundary mutation characteristics and internal consistency characteristics of each candidate segment, and combined with the corresponding set of adjacent branch nodes, a branch inheritance index for each candidate segment is constructed. Based on the topology and the validity of the internal measurement points of each candidate segment, a terminal missing measurement tolerance index is constructed for each candidate segment. The topological constraint characteristics of each candidate segment are obtained based on the upstream continuity index, downstream rejection index, branch inheritance index, and terminal missing test tolerance index.

[0014] This application first determines the upstream path set, downstream non-fault branch set, and adjacent branch node set of each candidate segment based on the topology. Then, combining the boundary abrupt change characteristics and internal consistency characteristics of each candidate segment, it sequentially constructs the upstream continuity index, downstream rejection index, and branch inheritance index of each candidate segment. Next, combining the topology and the effectiveness of the internal measurement points of each candidate segment, it constructs the terminal missing measurement tolerance index of each candidate segment, thereby obtaining the topological constraint characteristics of each candidate segment. Compared with the prior art, by considering the various indices associated with the topological information of each type of fault segment, the topological constraint characteristics obtained can cover the fault-related topological features in the fault segment, thus providing a data foundation for subsequent comprehensive application of multiple fault-related type features for location, thereby improving the accuracy of single-phase grounding fault segment location in the faulty distribution network.

[0015] In some embodiments of this application, the step of locating the target faulty section of the faulty distribution network from the plurality of candidate sections by combining the boundary abruptness characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate section specifically includes: Based on the topology and the transient characteristic data of the neighboring and internal measuring points of each candidate segment, a conflict penalty term is constructed for each candidate segment. The location score of each candidate segment is determined by combining the boundary abruptness features, internal consistency features, topological constraint features, and contradiction penalty terms of each candidate segment. The candidate segment with the highest location score is selected as the target fault segment of the faulty distribution network.

[0016] This application first constructs a contradiction penalty term for each candidate segment based on the topology and transient characteristic data of neighboring and internal measuring points of each candidate segment. Then, it determines the location score of each candidate segment by combining the boundary abrupt change characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate segment. Finally, it selects the candidate segment with the highest location score as the target fault segment. This approach can comprehensively cover and apply various types of fault characteristics, thereby improving the accuracy of locating single-phase grounding fault segments in the faulty distribution network.

[0017] In some embodiments of this application, after locating the target fault section of the faulty distribution network from the plurality of candidate sections, the method further includes: Based on the positioning score of each candidate segment, a first candidate segment and a second candidate segment are determined; wherein, the positioning score corresponding to the first candidate segment is the largest, and the positioning score corresponding to the second candidate segment is the second largest. Based on the location score, data quality features, topological constraint features, contradiction penalty term, and location score of the second candidate segment, the location reliability of the target fault segment is determined and output; wherein, the data quality features are calculated based on the transient feature data of each neighboring measuring point and each internal measuring point of the first candidate segment.

[0018] This application first determines the first and second candidate segments based on the location scores of each candidate segment. Then, it calculates and outputs the location reliability of the target fault segment by combining the data quality characteristics, topological constraint characteristics, and contradiction penalty terms of the first candidate segment. This can provide additional decision support information for the determination of the target fault segment, thereby providing a corresponding decision basis for further processing of the target fault segment.

[0019] According to a second aspect of the embodiments of this application, a single-phase grounding fault section location device for a distribution network is provided, including a data acquisition and section division module, a boundary abrupt change feature construction module, an internal consistency feature construction module, a topological constraint feature construction module, and a target fault section location module. The data acquisition and segment division module is used to acquire transient characteristic data of multiple measuring points of the faulted distribution network at the time of the fault, and divide the faulted distribution network into multiple candidate segments according to the topology of the faulted distribution network. The boundary abrupt change feature construction module is used to construct the boundary abrupt change feature of each candidate segment based on the transient feature data of the neighboring measurement points corresponding to each candidate segment; wherein, the neighboring measurement point is the measurement point that is closest to both ends of the corresponding candidate segment outside the corresponding candidate segment among the plurality of measurement points; The internal consistency feature construction module is used to construct the internal consistency feature of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment; wherein, the internal measurement points are all the measurement points in the corresponding candidate segment among the plurality of measurement points; The topology constraint feature construction module is used to construct the topology constraint features of each candidate segment based on the boundary abruptness features and internal consistency features of each candidate segment, combined with the topology structure. The target fault section location module is used to locate the target fault section of the faulty distribution network from the multiple candidate sections by combining the boundary abrupt change characteristics, internal consistency characteristics and topological constraint characteristics of each candidate section.

[0020] In some embodiments of this application, the data acquisition and segmentation module includes a reference point determination unit, a raw data acquisition unit, and a raw data processing unit; The reference point determination unit is used to determine the occurrence of a fault at each measuring point of the faulty distribution network according to a preset event criterion function, and to determine the local event reference point corresponding to each measuring point when the fault occurs. The raw data acquisition unit is used to acquire the transient feature components of each measuring point within a preset multiple time windows of the corresponding local event reference point, and obtain the raw transient feature data of each measuring point when the fault occurs. The raw data processing unit is used to remove the base value and normalize the raw transient feature data of each measuring point to obtain the transient feature data of each measuring point.

[0021] In some embodiments of this application, the neighboring measurement points include upstream neighboring measurement points and downstream neighboring measurement points; the boundary abrupt change feature construction module includes a mutation index construction unit and a mutation feature construction unit; The mutation index construction unit is used to obtain upstream transient feature data of upstream neighboring measurement points and downstream transient feature data of downstream neighboring measurement points corresponding to each candidate segment, and to construct polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment in sequence based on the upstream transient feature data and the downstream transient feature data. The mutation feature construction unit is used to obtain the boundary mutation features of each candidate segment based on the polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment.

[0022] In some embodiments of this application, the internal consistency feature construction module includes a consistency index construction unit and a consistency feature construction unit; The consistency index construction unit is used to construct the trend consistency index, polarity consistency index and decay interpretability index of each candidate segment in sequence based on the transient characteristic data of the internal measurement points corresponding to each candidate segment. The consistency feature construction unit is used to obtain the internal consistency features of each candidate segment based on the trend consistency index, polarity consistency index, and decay interpretability index of each candidate segment.

[0023] In some embodiments of this application, the topology constraint feature construction module includes a topology information acquisition unit, an upstream index construction unit, a downstream index construction unit, a branch index construction unit, a fault tolerance index construction unit, and a topology feature construction unit; The topology information acquisition unit is used to obtain the upstream path set, downstream non-faulty branch set, and adjacent branch node set for each candidate segment based on the topology structure. The upstream index construction unit is used to construct an upstream continuity index for each candidate segment based on the boundary abruptness characteristics of each candidate segment and the corresponding upstream path set. The downstream indicator construction unit is used to construct a downstream rejection indicator for each candidate segment based on the internal consistency characteristics of each candidate segment and the corresponding set of downstream non-fault branches. The branch index construction unit is used to construct a branch inheritance index for each candidate segment based on the boundary mutation characteristics and internal consistency characteristics of each candidate segment, combined with the corresponding set of adjacent branch nodes. The fault tolerance index construction unit is used to construct a terminal missing measurement fault tolerance index for each candidate segment based on the topology and the validity of the internal measurement points of each candidate segment. The topology feature construction unit is used to obtain the topology constraint features of each candidate segment based on the upstream continuity index, downstream rejection index, branch inheritance index, and terminal missing test tolerance index of each candidate segment.

[0024] In some embodiments of this application, the target fault section location module includes a contradiction penalty item construction unit, a section location score determination unit, and a target fault section location unit; The contradiction penalty term construction unit is used to construct a contradiction penalty term for each candidate segment based on the topology and the transient characteristic data of the neighboring and internal measuring points of each candidate segment. The segment location score determination unit is used to determine the location score of each candidate segment by combining the boundary abruptness features, internal consistency features, topological constraint features, and contradiction penalty terms of each candidate segment. The target fault section location unit is used to select the candidate section with the highest location score as the target fault section of the faulty distribution network.

[0025] In some embodiments of this application, a confidence calculation output module is also included; the confidence calculation output module includes an associated segment determination unit and a confidence calculation output unit; The associated segment determination unit is used to determine a first candidate segment and a second candidate segment based on the positioning score of each candidate segment; wherein the positioning score corresponding to the first candidate segment is the largest, and the positioning score corresponding to the second candidate segment is the second largest. The confidence calculation and output unit is used to determine and output the location confidence of the target fault segment based on the location score, data quality features, topological constraint features, contradiction penalty term and the location score of the first candidate segment and the second candidate segment; wherein, the data quality features are calculated based on the transient feature data of each neighboring measuring point and each internal measuring point of the first candidate segment.

[0026] This application first obtains transient characteristic data of multiple measuring points in a faulty distribution network at the time of the fault, and divides the faulty distribution network into multiple candidate segments according to the topology of the faulty distribution network. Then, in each candidate segment, boundary abrupt change features are constructed based on the transient characteristic data of the corresponding neighboring measuring points, internal consistency features are constructed based on the transient characteristic data of the corresponding internal measuring points, and topological constraint features are constructed based on the boundary abrupt change features, internal consistency features, and topology. Finally, the target fault segment is located from the multiple candidate segments. Compared with the prior art, this application utilizes the transient characteristic data of multiple measuring points in the faulty distribution network at the time of the fault, and constructs boundary abrupt change features associated with the abrupt change characteristics at the boundary of the fault segment, internal consistency features associated with the consistency among multiple measuring points within the fault segment, and topological constraint features associated with the topology information of the faulty distribution network. This comprehensively covers all types of fault characteristics in the fault segment, and then comprehensively applies the above features to locate the fault segment, which can improve the accuracy of locating single-phase grounding fault segments in the faulty distribution network.

[0027] According to a third aspect of the embodiments of this application, a computer device is provided, comprising: a processor; a memory; and a computer program stored in the memory and configured to be executed by the processor; wherein the processor executes the computer program to implement the method for locating a single-phase grounding fault section in a power distribution network as described in this application.

[0028] According to a fourth aspect of the embodiments of this application, a computer-readable storage medium is provided, the computer-readable storage medium storing a plurality of instructions adapted for loading by a processor to execute a method for locating a single-phase grounding fault section in a power distribution network as described in this application. Attached Figure Description

[0029] Figure 1 This is a flowchart illustrating a method for locating a single-phase grounding fault section in a power distribution network, as shown in certain embodiments of this application. Figure 2 This is a module structure diagram of a single-phase grounding fault location device for a power distribution network, as shown in certain embodiments of this application. Detailed Implementation

[0030] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below in conjunction with the accompanying drawings are exemplary and are only used to explain some embodiments of this application, and should not be construed as limiting the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments shown in this application without inventive effort are within the protection scope of this application.

[0031] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, unless otherwise explicitly specified, "a plurality of" or "several" means two or more.

[0032] Existing methods for locating single-phase grounding fault sections in medium and low voltage power distribution systems mainly include: (1) methods based on transient feature discrimination, which use the short-term changes in the power distribution network characteristics after the fault occurs to determine the section. These methods are highly dependent on specific frequency bands / models / thresholds. When the fault conditions change, their feature stability is insufficient, which can easily lead to misjudgment or missed judgment; (2) location methods based on multi-feature fusion, which combine multiple steady-state or transient indicators to improve the reliability of section location. However, these methods often focus on the fault characteristics of a single measuring point or a single section boundary, which is not suitable for the fault location of a single-phase grounding fault. The sudden change characteristics at the boundary of the fault section and the lack of attention to the consistency among multiple measuring points within the section lead to questionable accuracy in locating the actual fault section; (3) Combining network topology or fault propagation laws, the fault section is screened and located by further utilizing topology-related features such as feeder segmentation, upstream and downstream relationships and branch relationships. However, topology information is usually used as an auxiliary condition for post-fault screening and location, and the role of topology information in the short time after the fault occurs is not considered. When there are omissions in post-fault data collection, the accuracy of post-fault section screening and location based on topology information is obviously insufficient. Obviously, the current methods for locating single-phase ground faults in medium and low voltage power distribution systems have varying degrees of location defects. Therefore, how to improve the accuracy of single-phase ground fault location in medium and low voltage power distribution systems is still an urgent problem to be solved by existing technologies.

[0033] Based on the above technical background, please refer to Figure 1 This application provides a method for locating a single-phase ground fault section in a distribution network, including steps S101 to S105, each step of which is as follows: Step S101: Obtain transient characteristic data of multiple measuring points of the faulted distribution network at the time of the fault, and divide the faulted distribution network into multiple candidate segments according to the topology of the faulted distribution network.

[0034] To illustrate the implementation of the single-phase grounding fault location method for distribution networks provided in this application, a 10kV radial distribution feeder will be used as an example to illustrate the fault distribution network. This feeder includes a main line and several branch lines, with measurement points for collecting electrical quantities arranged at the segment nodes, branch nodes, or terminal nodes of these lines. Before and after the fault occurs, the main station on the feeder can acquire short-time waveform data corresponding to each measurement point and real-time topology information of the feeder. The short-time waveform data can be three-phase voltage, three-phase current, or zero-sequence voltage, zero-sequence current, or any zero-sequence component synthesized from three-phase electrical quantities. Generally, for the first... The zero-sequence voltage at each measuring point and zero-sequence current Represented as time The corresponding zero-sequence voltage and zero-sequence current values ​​can be synthesized from the corresponding three-phase voltage and three-phase current: ; In a feeder with a defined topology, the feeder can be divided into sections based on the locations of measuring points and switches. The candidate segment, the first Each candidate segment is denoted as .

[0035] In some embodiments of this application, acquiring transient characteristic data of multiple measuring points in the faulted distribution network at the time of the fault specifically includes: Based on a preset event criterion function, a fault occurrence determination is made for each measuring point in the faulty distribution network, and the local event reference point corresponding to each measuring point when the fault occurs is determined. The transient feature components of each measuring point within multiple preset time windows of the corresponding local event reference point are obtained to obtain the original transient feature data of each measuring point when the fault occurs. The original transient feature data of each measuring point is removed from the base and normalized to obtain the transient feature data of each measuring point.

[0036] Specifically, to reduce reliance on a strictly synchronized timescale across the entire network, and considering the actual time delay of fault propagation in the distribution network and the actual response delay of each measuring point to the fault, a unified absolute time across the entire network is not directly adopted. This avoids the situation where a uniform event reference point would lead to transient characteristic data that cannot correspond to the actual fault period. Instead, each measuring point independently identifies its local event reference point. It can be determined by one or more combinations of characteristic information generated by the fault, such as sudden changes in zero-sequence current, extreme values ​​of the zero-sequence voltage derivative, or sudden increases in the energy of the fault component. The corresponding event criterion function is defined as: ; in, For the first Each measuring point at time... The corresponding event criterion value; These are non-negative weighting coefficients, and ; For the first Each measuring point at time... The sliding short window energy term, The width of the sliding short window; Based on the definition of the event criterion function, the first Each measuring point at time... Time criterion value Within the preset fault observation range The time corresponding to the maximum value within is taken as the first Local event reference points for each measurement point: .

[0037] Specifically, in determining the local event reference point corresponding to the occurrence of the fault. Then, multiple time windows are constructed for fault analysis, including, in order: a baseline window before the fault. First transient window after a failure Delayed transient window after a fault and the attenuation observation window after the fault This allows for the separation and processing of initial fault mutation information, short-term duration information, and subsequent decay information; among which, The length of the reference window before the failure; The duration of the initial transient analysis; To extend the duration of transient analysis; To attenuate the observation duration. Preferably, Take 2-5 power frequency cycles. Take 0.5-2 power frequency cycles. Take 1-3 power frequency cycles. Take 2-5 power frequency cycles.

[0038] Specifically, when the main station on the feeder detects that the single-phase ground fault initiation conditions are met, each measuring point uses its own determined local event reference point as the fault occurrence time. Through the aforementioned multiple time windows, the main station extracts the signals to be processed (short-time waveform data) of each measuring point within a specific time range before and after the fault occurrence time. The initiation conditions for a single-phase ground fault can be obtained by one or more of the following: bus zero-sequence voltage exceeding the limit, feeder grounding alarm, sudden drop in fault phase voltage, or abnormal change in zero-sequence quantity. After the master station extracts the signal data to be processed from each measuring point, it first performs base value removal processing. Then normalization is performed. ( (The value is a very small positive number to prevent the denominator from being zero). Finally, resampling is performed to unify the data frequency and align the data to obtain standardized transient feature data with relative temporal alignment, providing a unified basis for subsequent feature extraction.

[0039] This application first uses an event criterion function to determine the local event reference point corresponding to each measuring point in the faulty distribution network at the time of the fault occurrence. Then, it obtains the transient feature components within multiple preset time windows to obtain the original transient feature data. Then, it obtains the transient feature data of each measuring point by removing the base value and normalizing. By using the event criterion function to determine the local event reference point for each measuring point, it considers the actual time delay of the fault propagation in the distribution network and the actual reaction delay of each measuring point to the fault. This avoids the situation where uniformly defining the event reference point would cause the obtained transient feature data to not correspond to the actual fault period, thereby avoiding the distortion of transient feature data, ensuring the correctness of transient feature data, and providing a correct data basis for locating single-phase grounding fault sections in the faulty distribution network.

[0040] Step S102: Construct boundary abrupt change features for each candidate segment based on the transient feature data of the neighboring measurement points corresponding to each candidate segment; wherein, the neighboring measurement point is the measurement point that is closest to both ends of the corresponding candidate segment outside the corresponding candidate segment among the multiple measurement points.

[0041] Specifically, when obtaining each candidate segment based on the topology partitioning of measurement points and switch locations, for the first... Candidate segments On the feeder line, there are multiple internal measurement points along the corresponding path. The measurement point located at the outermost edge of the corresponding segment in terms of topological distance is denoted as the two ends of the corresponding segment (one on the left and one on the right). Outside the corresponding segment, the measurement point that is closest to the two ends of the corresponding segment in terms of topological distance is called the neighboring measurement point, including the upstream neighboring measurement point. and downstream adjacent measuring points .

[0042] In some embodiments of this application, constructing the boundary abrupt change features of each candidate segment based on the transient feature data of neighboring measuring points corresponding to each candidate segment specifically includes: Acquire upstream transient characteristic data of upstream neighboring measuring points and downstream transient characteristic data of downstream neighboring measuring points corresponding to each candidate segment, and construct polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment in sequence based on the upstream transient characteristic data and the downstream transient characteristic data. Based on the polarity transition index, energy mutation index, morphological difference index, and decay gradient index corresponding to each candidate segment, the boundary mutation characteristics of each candidate segment are obtained.

[0043] Specifically, because real fault sections inherently possess the physical characteristic of "abrupt changes in electrical parameters," characterized by sudden changes in the direction, waveform, energy, and attenuation of electrical quantities, therefore, for the first... Candidate segments Its boundary mutation features can be constructed. To determine the abrupt change in its parameters, and then combine it with other types of features to filter out the target fault section, this boundary abrupt change feature... Polarity transition index Energy mutation index Morphological difference indicators and decay gradient index composition.

[0044] Furthermore, polarity transition index It can be achieved through upstream and downstream adjacent measuring points in the first transient window The polarity sign within is compared to define the integral sign; among them, the integral sign value of the fault component of the zero-sequence current at the upstream neighboring measuring point is defined based on the integral sign of the fault component of its zero-sequence current: ; The integral sign value of the fault component of the zero-sequence current at the downstream adjacent measuring point can be analogously defined as: ; Thus, polarity transition index It can be represented by its comparison as When the polarity signs of adjacent upstream and downstream measuring points are the same, the value is 0; otherwise, the value is 1.

[0045] Furthermore, energy mutation index It can be achieved through upstream and downstream adjacent measuring points in the first transient window and delayed transient window The normalized energy within the range is defined by comparison; where the normalized energy of the upstream neighboring measuring point is defined as: ; The normalized energy at downstream adjacent measuring points can be analogously defined as: ; Therefore, the energy mutation index It can be represented by its comparison as .

[0046] Furthermore, morphological difference indicators It can be achieved through upstream and downstream adjacent measuring points in the first transient window The correlation coefficient of the normalized waveform within the range is defined as follows: ; Therefore, morphological difference index It can be represented as When the waveforms are more similar, The closer to 1, The smaller the value, the more dissimilar the waveforms. The closer to 0, The larger.

[0047] Furthermore, the decay gradient index It can be achieved through upstream and downstream adjacent measuring points within the delay transient window. and attenuation observation window Defined by comparing the energy ratio within the time window; where the upstream neighboring measuring point is within the time delay transient window. and attenuation observation window The energy ratio within is defined as: ; Downstream adjacent measuring points are in the delayed transient window and attenuation observation window The energy ratio within can be analogously defined as: ; Thus decaying gradient index It can be represented by its comparison as .

[0048] Furthermore, the first Candidate segments Boundary mutation characteristics Polarity transition index Energy mutation index Morphological difference indicators and decay gradient index The linear weighted sum is calculated to obtain: The weight of each indicator All are non-negative numbers, and .

[0049] This application first obtains upstream transient characteristic data from upstream neighboring measuring points and downstream transient characteristic data from downstream neighboring measuring points for each candidate section. Then, based on the upstream and downstream transient characteristic data, it sequentially constructs polarity transition index, energy mutation index, morphological difference index, and attenuation gradient index for each candidate section, thereby obtaining the boundary mutation characteristics of each candidate section. Compared with the prior art, by considering the various indices associated with the mutation characteristics at the boundary of the fault section, the boundary mutation characteristics can be obtained, which can cover the data characteristics of fault-related boundary mutations in the fault section. This provides a data foundation for subsequent comprehensive application of multiple fault-related type characteristics for location, thereby improving the accuracy of single-phase grounding fault section location in the faulty distribution network.

[0050] Step S103: Construct the internal consistency feature of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment; wherein, the internal measurement points are all the measurement points in the corresponding candidate segment among the multiple measurement points.

[0051] Specifically, for the first Candidate segments The set of all available measuring points within the corresponding path or section on the feeder is: , For the first Candidate segments The number of measurement points involved in the analysis.

[0052] In some embodiments of this application, constructing the internal consistency features of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment specifically includes: Based on the transient characteristic data of the internal measurement points corresponding to each candidate segment, the trend consistency index, polarity consistency index, and attenuation interpretability index of each candidate segment are constructed in sequence. The internal consistency characteristics of each candidate segment are obtained based on the trend consistency index, polarity consistency index, and decay interpretability index.

[0053] Specifically, based on the actual division of each section, the distance between each measuring point within the actual fault section and the actual fault point differs significantly from the distance between each measuring point outside the fault section and the actual fault point. Therefore, all measuring points within the fault section should have electrical characteristics similar to those of the actual fault point, characterized by a convergence in the direction, trend, and energy attenuation of electrical quantities. Thus, for the first... Candidate segments It can construct its internal consistency characteristics. To determine the convergence of its parameters, and then combine it with other types of features to filter out the target fault section, this internal consistency feature... By trend consistency index Polarity Consistency Index and attenuation interpretability index composition.

[0054] Furthermore, trend consistency indicators It can be achieved through the communication between each internal measurement point in the first transient window. and delayed transient window The correlation coefficient within the internal measurement points is defined as follows; where, for any two internal measurement points... The correlation coefficient is defined as: ; Thus, the trend consistency index It can be expressed as the correlation coefficient of all its internal measuring points. .

[0055] Furthermore, the polarity consistency index It can be measured at each internal measurement point in the first transient window The polarity sign within is used to define it; where, the innermost polarity sign is used to define the polarity sign within the polarity sign. The polarity sign of each measuring point, based on the integral sign of the fault component of its zero-sequence current, is defined as follows: ; Thus, the polarity consistency index It can be represented by combining the polarity signs of all its internal measuring points as When the polarities of all internal measuring points tend to converge, Approaching 1; when polarity is dispersed, It is divergent and less than 1.

[0056] Furthermore, the attenuation interpretability index It can be achieved through each internal measurement point within the delay transient window and attenuation observation window The attenuation coefficient within is defined as the in-terminate factor; where the in-terminate factor is the first... The attenuation coefficient at each measurement point is based on its delay transient window. and attenuation observation window The energy ratio within is defined as: ; This leads to a decrease in the interpretability index. The attenuation coefficients of all its internal measuring points can be expressed as follows: ;in, This represents the variance; the smaller the dispersion of the attenuation coefficients at each internal measuring point, the more consistent the attenuation relationship among the internal measuring points. The larger.

[0057] Furthermore, the first Candidate segments Internal consistency characteristics Trend consistency indicators Polarity Consistency Index and attenuation interpretability index The linear weighted sum is calculated to obtain: The weight of each indicator All are non-negative numbers, and .

[0058] This application first constructs corresponding trend consistency index, polarity consistency index, and attenuation interpretability index based on the transient characteristic data of the internal measuring points of each candidate section, thereby obtaining the internal consistency characteristics of each candidate section. Compared with the prior art, by considering the various indices of the consistency correlation between multiple measuring points within the fault section regarding the fault, the internal consistency characteristics can be obtained. This can cover the data characteristics between multiple internal measuring points related to the fault in the fault section, thereby providing a data foundation for subsequent comprehensive application of various fault-related type features for location, thus improving the accuracy of single-phase grounding fault section location in the faulty distribution network.

[0059] Step S104: Based on the boundary abrupt change characteristics and internal consistency characteristics of each candidate segment, and in conjunction with the topology, construct the topological constraint characteristics of each candidate segment.

[0060] In some embodiments of this application, the step of constructing the topological constraint features of each candidate segment based on its boundary abruptness and internal consistency features, combined with the topological structure, specifically includes: Based on the topology, the upstream path set, downstream non-faulty branch set, and adjacent branch node set of each candidate segment are obtained; Based on the boundary abrupt change characteristics of each candidate segment and combined with the corresponding upstream path set, an upstream continuity index is constructed for each candidate segment. Based on the internal consistency characteristics of each candidate segment and combined with the corresponding set of downstream non-faulty branches, a downstream rejection index is constructed for each candidate segment. Based on the boundary mutation characteristics and internal consistency characteristics of each candidate segment, and combined with the corresponding set of adjacent branch nodes, a branch inheritance index for each candidate segment is constructed. Based on the topology and the validity of the internal measurement points of each candidate segment, a terminal missing measurement tolerance index is constructed for each candidate segment. The topological constraint characteristics of each candidate segment are obtained based on the upstream continuity index, downstream rejection index, branch inheritance index, and terminal missing test tolerance index.

[0061] Specifically, since the actual faulty section is not isolated but embedded in the topology of the entire distribution network, the measurement points upstream, downstream, and adjacent branches must satisfy the physical laws of fault propagation. Therefore, for the first... Candidate segments Its topological constraint features can be constructed. To determine its topological logicality, and then combine it with other types of features to filter out the target fault section, this topological constraint feature... From upstream continuity indicators Downstream rejection indicators Branch inheritance index Terminal fault tolerance index Composition; based on the topology of the distribution network, for the first Candidate segments Its upstream path set can be represented as The set of downstream non-faulty branches can be represented as The set of adjacent branch nodes can be represented as .

[0062] Furthermore, upstream continuity indicators This is characterized by the electrical continuity of upstream non-faulty nodes, ensuring the validity of the current candidate segment as a fault, and can be achieved through the upstream path set. The number of nodes that satisfy the continuous propagation constraint Total number of upstream path nodes Defined by the ratio; satisfying the continuous propagation constraint, characterized as the first... Candidate segments The electrical quantity characteristics among the nodes to be tested in the upstream path are the same or convergent, and the boundary characteristics are continuous and smooth; upstream continuity index The specific formula is as follows: .

[0063] Furthermore, downstream rejection indicators This is characterized by the non-abnormal characteristics of downstream non-faulty branches, ensuring the validity of the current candidate segment as a fault. This can be achieved through the set of downstream non-faulty branches. The number of branches showing obvious abnormal consistency Total number of downstream non-faulty branches Defined by the ratio; obvious abnormal consistency is characterized as the first... Candidate segments The downstream non-faulty branches exhibit fault-related electrical quantity characteristics, boundary characteristics, or internal consistency characteristics; downstream rejection indicators The specific formula is as follows: .

[0064] Furthermore, branch inheritance indicators This is characterized by the requirement that nodes adjacent to the current candidate segment must satisfy the topological rules of the distribution network to ensure the validity of the current candidate segment as a normal logical segment. This can be achieved through the set of adjacent branch nodes. The number of test nodes that satisfy the shunting or attenuation law Total number of inspection nodes Defined by the ratio; branch inheritance index The specific formula is as follows: .

[0065] Furthermore, terminal fault tolerance indicators This is characterized by the data integrity / missing measurement tolerance of the measurement points related to the current candidate segment, to ensure the validity of the data for the current candidate segment. This can be achieved through the [missing information - likely a specific method or mechanism]. Candidate segments Number of valid measurement points involved Number of measurement points Defined by the ratio; Terminal Failure Tolerance Index The specific formula is as follows: .

[0066] Furthermore, the first Candidate segments Topological constraint features Upstream continuity indicators can be used Downstream rejection indicators Branch inheritance index Terminal fault tolerance index The linear weighted sum is calculated to obtain: The weight of each indicator All are non-negative numbers, and .

[0067] This application first determines the upstream path set, downstream non-fault branch set, and adjacent branch node set of each candidate segment based on the topology. Then, combining the boundary abrupt change characteristics and internal consistency characteristics of each candidate segment, it sequentially constructs the upstream continuity index, downstream rejection index, and branch inheritance index of each candidate segment. Next, combining the topology and the effectiveness of the internal measurement points of each candidate segment, it constructs the terminal missing measurement tolerance index of each candidate segment, thereby obtaining the topological constraint characteristics of each candidate segment. Compared with the prior art, by considering the various indices associated with the topological information of each type of fault segment, the topological constraint characteristics obtained can cover the fault-related topological features in the fault segment, thus providing a data foundation for subsequent comprehensive application of multiple fault-related type features for location, thereby improving the accuracy of single-phase grounding fault segment location in the faulty distribution network.

[0068] Step S105: Combining the boundary abrupt change characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate segment, locate the target fault segment of the faulty distribution network from the multiple candidate segments.

[0069] In some embodiments of this application, the step of locating the target faulty section of the faulty distribution network from the plurality of candidate sections by combining the boundary abruptness characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate section specifically includes: Based on the topology and the transient characteristic data of the neighboring and internal measuring points of each candidate segment, a conflict penalty term is constructed for each candidate segment. The location score of each candidate segment is determined by combining the boundary abruptness features, internal consistency features, topological constraint features, and contradiction penalty terms of each candidate segment. The candidate segment with the highest location score is selected as the target fault segment of the faulty distribution network.

[0070] Specifically, for any candidate segment, it should satisfy the corresponding physical laws in terms of topology or data quality; therefore, for the first... Candidate segments It is possible to construct its contradictory penalty items. This is used to characterize the penalty for inconsistencies in topology or data quality, and then combined with other types of features to filter out target fault sections. This inconsistency penalty term... It consists of the number of topological conflicts, the integrity rate of data quality features, and the number of obviously contradictory branches.

[0071] Specifically, to enhance adaptability to different working conditions, for the first... Candidate segments Data quality characteristics This data quality feature is used to characterize its data quality. Completeness index Signal-to-noise ratio and relative timing reliability index composition.

[0072] Furthermore, the completeness rate indicator The specific formula is as follows: .

[0073] Furthermore, the signal-to-noise ratio (SNR) metric The specific formula is as follows: And truncate it to the interval [0,1]; in, These are the lower and upper limits of the preset signal-to-noise ratio, respectively.

[0074] Furthermore, relative time-series reliability indicators It can be defined by the dispersion of local event reference points at each measurement point within the current candidate segment; relative time series reliability index The specific formula is as follows: And truncate it to the interval [0,1]; in, Indicates standard deviation; This represents the relative time tolerance threshold.

[0075] Furthermore, data quality characteristics Completeness rate metric Signal-to-noise ratio and relative timing reliability index The linear weighted sum is calculated to obtain: The weight of each indicator All are non-negative numbers, and .

[0076] Furthermore, the conflict penalty item It consists of the number of topological conflicts, the data quality feature completeness index, and the number of obviously contradictory branches, and its specific formula is as follows: ; in, For the first Each candidate segment involves the number of nodes with topological conflicts; For the first The number of nodes in the set of adjacent branch nodes of each candidate segment that have obviously contradictory branches; .

[0077] Furthermore, for the first Candidate segments Its positioning score The specific formula is as follows: ; in, Weights for each feature; Thus through the formula The candidate segment number is determined, thereby identifying the target faulty segment. The candidate segment with the highest location score is selected as the target fault segment.

[0078] Specifically, the weights of each feature can also be determined through data quality characteristics. Adaptive correction is performed, specifically as follows: ; ; ; Then normalize to obtain the corrected weights, specifically: ; ; ; in, These are the initial weights; For each adjustment coefficient; Thus, the weights of each feature are determined by the data quality characteristics. Adaptive correction can enhance the role of boundary abrupt change features when the information in the first transient window is clear, and enhance the role of internal consistency features and topological constraint features when the integrity of the measurement points is high, thereby further leveraging the physical and logical contribution of each measurement point to the location of the target fault section.

[0079] This application first constructs a contradiction penalty term for each candidate segment based on the topology and transient characteristic data of neighboring and internal measuring points of each candidate segment. Then, it determines the location score of each candidate segment by combining the boundary abrupt change characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate segment. Finally, it selects the candidate segment with the highest location score as the target fault segment. This approach can comprehensively cover and apply various types of fault characteristics, thereby improving the accuracy of locating single-phase grounding fault segments in the faulty distribution network.

[0080] In some embodiments of this application, after locating the target fault section of the faulty distribution network from the plurality of candidate sections, the method further includes: Based on the positioning score of each candidate segment, a first candidate segment and a second candidate segment are determined; wherein, the positioning score corresponding to the first candidate segment is the largest, and the positioning score corresponding to the second candidate segment is the second largest. Based on the location score, data quality features, topological constraint features, contradiction penalty term, and location score of the second candidate segment, the location reliability of the target fault segment is determined and output; wherein, the data quality features are calculated based on the transient feature data of each neighboring measuring point and each internal measuring point of the first candidate segment.

[0081] Specifically, the location reliability of the target fault section The location score can be obtained from the first candidate segment. Data quality characteristics Topological constraint features Conflict Punishment Items Location score of the second candidate segment The calculation is performed using the following formula: ; Among them, each confidence level is assigned a weight. .

[0082] Furthermore, the location confidence of the target faulty section can be determined. Mapping to the [0,1] interval yields the mapping location confidence. Specifically: ; When the mapping location confidence is higher than the high confidence threshold When the confidence level is between the high confidence threshold and the medium confidence threshold, output the high confidence localization result (output the first candidate segment); when the mapping localization confidence level is between the high confidence threshold and the medium confidence threshold, output the high confidence localization result (output the first candidate segment). When the confidence level of the mapped location is lower than the median confidence threshold, output the localization result with medium confidence (and simultaneously output the first and second candidate segments); when the localization confidence level is lower than the median confidence threshold, output the localization result with medium confidence (and simultaneously output the first and second candidate segments). When this happens, output the set of low-confidence candidate segments (output all current candidate segments). Preferably, The preferred value is 0.75. The preferred value is 0.45.

[0083] This application first determines the first and second candidate segments based on the location scores of each candidate segment. Then, it calculates and outputs the location reliability of the target fault segment by combining the data quality characteristics, topological constraint characteristics, and contradiction penalty terms of the first candidate segment. This can provide additional decision support information for the determination of the target fault segment, thereby providing a corresponding decision basis for further processing of the target fault segment.

[0084] Compared to existing technologies, this application first obtains transient characteristic data of multiple measuring points in a faulty distribution network at the time of the fault, and divides the faulty distribution network into multiple candidate segments according to the topology of the faulty distribution network. Then, in each candidate segment, boundary abrupt change features are constructed based on the transient characteristic data of the corresponding neighboring measuring points, internal consistency features are constructed based on the transient characteristic data of the corresponding internal measuring points, and topological constraint features are constructed based on the boundary abrupt change features, internal consistency features, and topology. Finally, the target fault segment is located from the multiple candidate segments. Compared to existing technologies, this application utilizes transient characteristic data of multiple measuring points in a faulty distribution network at the time of the fault, and constructs boundary abrupt change features associated with the abrupt change characteristics at the boundary of the fault segment, internal consistency features associated with the consistency among multiple measuring points within the fault segment, and topological constraint features associated with the topology information of the faulty distribution network. This comprehensively covers all types of fault characteristics in the fault segment, and then comprehensively applies the above features to locate the fault segment, which can improve the accuracy of locating single-phase grounding fault segments in a faulty distribution network.

[0085] For a method corresponding to the one described above, please refer to [link / reference]. Figure 2 This application provides a single-phase grounding fault section location device for a distribution network, including a data acquisition and section division module 210, a boundary abrupt change feature construction module 220, an internal consistency feature construction module 230, a topology constraint feature construction module 240, and a target fault section location module 250. The data acquisition and segment division module 210 is used to acquire transient characteristic data of multiple measuring points of the faulted distribution network at the time of the fault, and divide the faulted distribution network into multiple candidate segments according to the topology of the faulted distribution network. The boundary abrupt change feature construction module 220 is used to construct the boundary abrupt change feature of each candidate segment based on the transient feature data of the neighboring measurement points corresponding to each candidate segment; wherein, the neighboring measurement point is the measurement point that is closest to both ends of the corresponding candidate segment outside the corresponding candidate segment among the plurality of measurement points. The internal consistency feature construction module 230 is used to construct the internal consistency feature of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment; wherein, the internal measurement points are all the measurement points in the corresponding candidate segment among the plurality of measurement points; The topology constraint feature construction module 240 is used to construct the topology constraint features of each candidate segment based on the boundary abruptness features and internal consistency features of each candidate segment, combined with the topology structure. The target fault section location module 250 is used to locate the target fault section of the faulty distribution network from the multiple candidate sections by combining the boundary abrupt change characteristics, internal consistency characteristics and topological constraint characteristics of each candidate section.

[0086] In some embodiments of this application, the data acquisition and segmentation module 210 includes a reference point determination unit, a raw data acquisition unit, and a raw data processing unit; The reference point determination unit is used to determine the occurrence of a fault at each measuring point of the faulty distribution network according to a preset event criterion function, and to determine the local event reference point corresponding to each measuring point when the fault occurs. The raw data acquisition unit is used to acquire the transient feature components of each measuring point within a preset multiple time windows of the corresponding local event reference point, and obtain the raw transient feature data of each measuring point when the fault occurs. The raw data processing unit is used to remove the base value and normalize the raw transient feature data of each measuring point to obtain the transient feature data of each measuring point.

[0087] In some embodiments of this application, the neighboring measurement points include upstream neighboring measurement points and downstream neighboring measurement points; the boundary abrupt change feature construction module 220 includes a mutation index construction unit and a mutation feature construction unit; The mutation index construction unit is used to obtain upstream transient feature data of upstream neighboring measurement points and downstream transient feature data of downstream neighboring measurement points corresponding to each candidate segment, and to construct polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment in sequence based on the upstream transient feature data and the downstream transient feature data. The mutation feature construction unit is used to obtain the boundary mutation features of each candidate segment based on the polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment.

[0088] In some embodiments of this application, the internal consistency feature construction module 230 includes a consistency index construction unit and a consistency feature construction unit; The consistency index construction unit is used to construct the trend consistency index, polarity consistency index and decay interpretability index of each candidate segment in sequence based on the transient characteristic data of the internal measurement points corresponding to each candidate segment. The consistency feature construction unit is used to obtain the internal consistency features of each candidate segment based on the trend consistency index, polarity consistency index, and decay interpretability index of each candidate segment.

[0089] In some embodiments of this application, the topology constraint feature construction module 240 includes a topology information acquisition unit, an upstream index construction unit, a downstream index construction unit, a branch index construction unit, a fault tolerance index construction unit, and a topology feature construction unit. The topology information acquisition unit is used to obtain the upstream path set, downstream non-faulty branch set, and adjacent branch node set for each candidate segment based on the topology structure. The upstream index construction unit is used to construct an upstream continuity index for each candidate segment based on the boundary abruptness characteristics of each candidate segment and the corresponding upstream path set. The downstream indicator construction unit is used to construct a downstream rejection indicator for each candidate segment based on the internal consistency characteristics of each candidate segment and the corresponding set of downstream non-fault branches. The branch index construction unit is used to construct a branch inheritance index for each candidate segment based on the boundary mutation characteristics and internal consistency characteristics of each candidate segment, combined with the corresponding set of adjacent branch nodes. The fault tolerance index construction unit is used to construct a terminal missing measurement fault tolerance index for each candidate segment based on the topology and the validity of the internal measurement points of each candidate segment. The topology feature construction unit is used to obtain the topology constraint features of each candidate segment based on the upstream continuity index, downstream rejection index, branch inheritance index, and terminal missing test tolerance index of each candidate segment.

[0090] In some embodiments of this application, the target fault section location module 250 includes a contradiction penalty item construction unit, a section location score determination unit, and a target fault section location unit; The contradiction penalty term construction unit is used to construct a contradiction penalty term for each candidate segment based on the topology and the transient characteristic data of the neighboring and internal measuring points of each candidate segment. The segment location score determination unit is used to determine the location score of each candidate segment by combining the boundary abruptness features, internal consistency features, topological constraint features, and contradiction penalty terms of each candidate segment. The target fault section location unit is used to select the candidate section with the highest location score as the target fault section of the faulty distribution network.

[0091] In some embodiments of this application, a confidence calculation output module is also included; the confidence calculation output module includes an associated segment determination unit and a confidence calculation output unit; The associated segment determination unit is used to determine a first candidate segment and a second candidate segment based on the positioning score of each candidate segment; wherein the positioning score corresponding to the first candidate segment is the largest, and the positioning score corresponding to the second candidate segment is the second largest. The confidence calculation and output unit is used to determine and output the location confidence of the target fault segment based on the location score, data quality features, topological constraint features, contradiction penalty term and the location score of the first candidate segment and the second candidate segment; wherein, the data quality features are calculated based on the transient feature data of each neighboring measuring point and each internal measuring point of the first candidate segment.

[0092] This application first obtains transient characteristic data of multiple measuring points in a faulty distribution network at the time of the fault, and divides the faulty distribution network into multiple candidate segments according to the topology of the faulty distribution network. Then, in each candidate segment, boundary abrupt change features are constructed based on the transient characteristic data of the corresponding neighboring measuring points, internal consistency features are constructed based on the transient characteristic data of the corresponding internal measuring points, and topological constraint features are constructed based on the boundary abrupt change features, internal consistency features, and topology. Finally, the target fault segment is located from the multiple candidate segments. Compared with the prior art, this application utilizes the transient characteristic data of multiple measuring points in the faulty distribution network at the time of the fault, and constructs boundary abrupt change features associated with the abrupt change characteristics at the boundary of the fault segment, internal consistency features associated with the consistency among multiple measuring points within the fault segment, and topological constraint features associated with the topology information of the faulty distribution network. This comprehensively covers all types of fault characteristics in the fault segment, and then comprehensively applies the above features to locate the fault segment, which can improve the accuracy of locating single-phase grounding fault segments in the faulty distribution network.

[0093] It should be understood that the device provided in the embodiments of this application is corresponding to the aforementioned method. The distribution network single-phase grounding fault section location device provided in the embodiments of this application can realize the distribution network single-phase grounding fault section location method provided in any embodiment of this application.

[0094] Adaptively, embodiments of this application also provide a computer device and a computer-readable storage medium.

[0095] The computer device includes: a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor; The processor executes the computer program to implement a method for locating a single-phase grounding fault section in a power distribution network, as described in this application.

[0096] The computer-readable storage medium stores multiple instructions, which are adapted for a processor to load and execute a method for locating a single-phase grounding fault section in a power distribution network according to this application.

[0097] The above description represents some embodiments of this application, providing a further detailed explanation of the purpose, technical solution, and beneficial effects of this application. It should be understood that the above-described embodiments of this application should not be construed as limiting this application. In particular, any changes, modifications, equivalent substitutions, and variations made by those skilled in the art within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for locating a single-phase grounding fault section in a distribution network, characterized in that, include: The transient characteristic data of multiple measuring points in the faulted distribution network at the time of the fault occurrence are obtained, and the faulted distribution network is divided into multiple candidate segments according to the topology of the faulted distribution network. Based on the transient feature data of the neighboring measuring points corresponding to each candidate segment, the boundary abrupt change feature of each candidate segment is constructed; wherein, the neighboring measuring point is the measuring point that is closest to both ends of the corresponding candidate segment outside the corresponding candidate segment among the plurality of measuring points; Based on the transient feature data of the internal measurement points corresponding to each candidate segment, an internal consistency feature is constructed for each candidate segment; wherein, the internal measurement points are all the measurement points within the corresponding candidate segment among the plurality of measurement points; Based on the boundary abrupt change characteristics and internal consistency characteristics of each candidate segment, and in conjunction with the topology, the topological constraint characteristics of each candidate segment are constructed. By combining the boundary abrupt change characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate segment, the target fault segment of the faulty distribution network is located from the multiple candidate segments.

2. The method for locating a single-phase grounding fault section in a distribution network according to claim 1, characterized in that, The acquisition of transient characteristic data of multiple measuring points in the faulted distribution network at the time of the fault specifically includes: Based on a preset event criterion function, a fault occurrence determination is made for each measuring point in the faulty distribution network, and the local event reference point corresponding to each measuring point when the fault occurs is determined. The transient feature components of each measuring point within multiple preset time windows of the corresponding local event reference point are obtained to obtain the original transient feature data of each measuring point when the fault occurs. The original transient feature data of each measuring point is removed from the base and normalized to obtain the transient feature data of each measuring point.

3. The method for locating a single-phase grounding fault section in a distribution network according to claim 1, characterized in that, The neighboring measuring points include upstream neighboring measuring points and downstream neighboring measuring points; the construction of boundary abrupt change features for each candidate segment based on the transient feature data of the neighboring measuring points corresponding to each candidate segment specifically includes: Acquire upstream transient characteristic data of upstream neighboring measuring points and downstream transient characteristic data of downstream neighboring measuring points corresponding to each candidate segment, and construct polarity transition index, energy mutation index, morphological difference index and decay gradient index corresponding to each candidate segment in sequence based on the upstream transient characteristic data and the downstream transient characteristic data. Based on the polarity transition index, energy mutation index, morphological difference index, and decay gradient index corresponding to each candidate segment, the boundary mutation characteristics of each candidate segment are obtained.

4. The method for locating a single-phase grounding fault section in a distribution network according to claim 1, characterized in that, The step of constructing the internal consistency features of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment specifically includes: Based on the transient characteristic data of the internal measurement points corresponding to each candidate segment, the trend consistency index, polarity consistency index, and attenuation interpretability index of each candidate segment are constructed in sequence. The internal consistency characteristics of each candidate segment are obtained based on the trend consistency index, polarity consistency index, and decay interpretability index.

5. The method for locating a single-phase grounding fault section in a distribution network according to claim 1, characterized in that, The step of constructing topological constraint features for each candidate segment based on its boundary abruptness and internal consistency features, combined with the topological structure, specifically includes: Based on the topology, the upstream path set, downstream non-faulty branch set, and adjacent branch node set of each candidate segment are obtained; Based on the boundary abrupt change characteristics of each candidate segment and combined with the corresponding upstream path set, an upstream continuity index is constructed for each candidate segment. Based on the internal consistency characteristics of each candidate segment and combined with the corresponding set of downstream non-faulty branches, a downstream rejection index is constructed for each candidate segment. Based on the boundary mutation characteristics and internal consistency characteristics of each candidate segment, and combined with the corresponding set of adjacent branch nodes, a branch inheritance index for each candidate segment is constructed. Based on the topology and the validity of the internal measurement points of each candidate segment, a terminal missing measurement tolerance index is constructed for each candidate segment. The topological constraint characteristics of each candidate segment are obtained based on the upstream continuity index, downstream rejection index, branch inheritance index, and terminal missing test tolerance index.

6. The method for locating a single-phase grounding fault section in a distribution network according to claim 1, characterized in that, The process of locating the target faulty section of the faulty distribution network from the multiple candidate sections by combining the boundary abruptness characteristics, internal consistency characteristics, and topological constraint characteristics of each candidate section specifically includes: Based on the topology and the transient characteristic data of the neighboring and internal measuring points of each candidate segment, a conflict penalty term is constructed for each candidate segment. The location score of each candidate segment is determined by combining the boundary abruptness features, internal consistency features, topological constraint features, and contradiction penalty terms of each candidate segment. The candidate segment with the highest location score is selected as the target fault segment of the faulty distribution network.

7. The method for locating a single-phase grounding fault section in a distribution network according to claim 6, characterized in that, After locating the target faulty section of the faulty distribution network from the plurality of candidate sections, the method further includes: Based on the positioning score of each candidate segment, a first candidate segment and a second candidate segment are determined; wherein, the positioning score corresponding to the first candidate segment is the largest, and the positioning score corresponding to the second candidate segment is the second largest. Based on the location score, data quality features, topological constraint features, contradiction penalty term, and location score of the second candidate segment, the location reliability of the target fault segment is determined and output; wherein, the data quality features are calculated based on the transient feature data of each neighboring measuring point and each internal measuring point of the first candidate segment.

8. A device for locating single-phase grounding fault sections in a power distribution network, characterized in that, It includes a data acquisition and segmentation module, a boundary mutation feature construction module, an internal consistency feature construction module, a topological constraint feature construction module, and a target fault segment location module; The data acquisition and segment division module is used to acquire transient characteristic data of multiple measuring points of the faulted distribution network at the time of the fault, and divide the faulted distribution network into multiple candidate segments according to the topology of the faulted distribution network. The boundary abrupt change feature construction module is used to construct the boundary abrupt change feature of each candidate segment based on the transient feature data of the neighboring measurement points corresponding to each candidate segment; wherein, the neighboring measurement point is the measurement point that is closest to both ends of the corresponding candidate segment outside the corresponding candidate segment among the plurality of measurement points; The internal consistency feature construction module is used to construct the internal consistency feature of each candidate segment based on the transient feature data of the internal measurement points corresponding to each candidate segment; wherein, the internal measurement points are all the measurement points in the corresponding candidate segment among the plurality of measurement points; The topology constraint feature construction module is used to construct the topology constraint features of each candidate segment based on the boundary abruptness features and internal consistency features of each candidate segment, combined with the topology structure. The target fault section location module is used to locate the target fault section of the faulty distribution network from the multiple candidate sections by combining the boundary abrupt change characteristics, internal consistency characteristics and topological constraint characteristics of each candidate section.

9. A computer device, characterized in that, include: processor; Memory; A computer program stored in the memory and configured to be executed by the processor; When the processor executes the computer program, it implements a method for locating a single-phase ground fault section in a distribution network as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a plurality of instructions adapted for loading by a processor to execute a method for locating a single-phase grounding fault section in a power distribution network as described in any one of claims 1 to 7.

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