Method, system and device for detecting grounding fault of power distribution network, and computer equipment

Abstract

The invention relates to a power distribution network ground fault detection method, system and device, and computer equipment. The method comprises the following steps: acquiring an initial fault signal of the power distribution network, wherein the power distribution network comprises a plurality of monitoring points; the actual time when the initial fault signal reaches different monitoring points is obtained, under the condition that the actual time is matched with the theoretical time, the initial fault signal is determined to be a homologous fault signal, and the theoretical time is obtained through calculation according to the distance between the different monitoring points and the signal propagation rate; and under the condition that the homologous fault signal has associated characteristics at at least two monitoring points, the homologous fault signal is determined to be a real fault signal, and the associated characteristics at least comprise characteristics associated with electrical quantities detected by different monitoring points.

Description

Technical Field

[0001] This application relates to the technical field of power system protection and control, and particularly to a detection method, system, device, and computer equipment for grounding faults in a distribution network. Background Art

[0002] With the large-scale access of distributed energy and power electronic loads in the distribution network, system grounding faults exhibit complex characteristics such as high impedance, intermittency, and multi-state coupling. Traditional protection systems usually adopt a single-level protection strategy: the substation layer relies on zero-sequence overvoltage protection, the line side uses zero-sequence current direction protection, and the user side is equipped with residual current protection. However, traditional methods are difficult to achieve accurate fault location and rapid isolation, affecting the safe operation level of the distribution network. Summary of the Invention

[0003] Based on this, in view of the above technical problems, it is necessary to provide a detection method, system, device, and computer equipment for grounding faults in a distribution network.

[0004] In a first aspect, this application provides a detection method for grounding faults in a distribution network. The method includes:

[0005] Obtain an initial fault signal of the distribution network, where the distribution network includes multiple monitoring points;

[0006] Obtain the actual time when the initial fault signal arrives at different monitoring points. When the actual time matches the theoretical time, determine that the initial fault signal is a homologous fault signal, and the theoretical time is calculated based on the distance between the different monitoring points and the signal propagation rate;

[0007] When the homologous fault signal has associated features at at least two monitoring points, determine that the homologous fault signal is a real fault signal, and the associated features at least include the features of the electrical quantities detected at different monitoring points being associated.

[0008] In one embodiment, the obtaining the actual time when the initial fault signal arrives at different monitoring points includes:

[0009] Perform complex wavelet transform on the initial fault signal to obtain the transformed waveform;

[0010] Extract the time corresponding to the extreme points in the waveform as the actual time when the waveform arrives at the monitoring point.

[0011] In one embodiment, the obtaining method for the distance between different monitoring points and the signal propagation rate includes:

[0012] Based on satellite positioning, obtain the coordinates of the monitoring points, and calculate the distance between the monitoring points based on the coordinates of the monitoring points;

[0013] Obtain real-time meteorological data, obtain the corrected dielectric constant based on the real-time meteorological data, and obtain the signal propagation rate based on the corrected dielectric constant and the speed of light.

[0014] In one embodiment, after determining that the homologous fault signal is a real fault signal, the method further includes:

[0015] Obtain the monitoring points of the distribution network, and initiate a collaborative disposal operation. The monitoring points at least include a substation layer, a line layer, and a user-side energy storage device;

[0016] The collaborative disposal operation includes that the substation layer adjusts the grounding reactance value, the line layer switch performs directional blocking, the user-side energy storage device injects a compensation current to assist in arc extinguishing, and reactive power compensation is realized based on a superconducting magnetic energy storage system.

[0017] In one embodiment, the method further includes:

[0018] Restore the distribution network path based on a preset two-layer model. The upper layer model of the preset two-layer model generates an initial restoration path based on an improved particle swarm algorithm, and the lower layer model calculates the evaluation index of the initial restoration path based on a quantum annealing algorithm, and selects the initial restoration path corresponding to the first-ranked evaluation index as the new distribution network path.

[0019] In one embodiment, before restoring the distribution network path, the method includes:

[0020] Perform a loop closing operation on the distribution network, and collect the voltage phase angle difference of the distribution network after loop closing;

[0021] Trigger dynamic reactive power compensation when the voltage phase angle difference exceeds a preset phase angle difference;

[0022] Obtain the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate of the distribution network, calculate the comprehensive index of the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate based on the interval membership function, and restore the distribution network path when the comprehensive index is greater than a preset index.

[0023] In a second aspect, the present application further provides a detection device for distribution network grounding faults. The device includes:

[0024] An acquisition module, configured to acquire the initial fault signal of the distribution network, where the distribution network includes a plurality of monitoring points;

[0025] A determination module, configured to obtain the actual time when the initial fault signal arrives at different monitoring points, and determine that the initial fault signal is a homologous fault signal when the actual time matches the theoretical time, where the theoretical time is calculated according to the distance between the different monitoring points and the signal propagation rate;

[0026] A detection module, configured to determine that the homologous fault signal is a real fault signal when there are associated features of the homologous fault signal at at least two monitoring points, where the associated features at least include the features of the electrical quantities detected at different monitoring points being associated.

[0027] In a third aspect, the present application further provides a detection system for a grounding fault in a distribution network, where the system includes:

[0028] A substation layer terminal, configured at the neutral point of the distribution network, for real-time monitoring of zero-sequence voltage and grounding converter parameters;

[0029] A line layer terminal, configured at the head end of each feeder of the distribution network, for synchronously collecting three-phase current and voltage and transient high-frequency components;

[0030] A user side terminal, configured at a key user access point, for detecting the load current distortion rate and grounding leakage current;

[0031] A master station collaborative control platform, connected to each terminal.

[0032] In a fourth aspect, the present disclosure further provides a computer device. The computer device includes a memory and a processor, where the memory stores a computer program, and when the processor executes the computer program, the steps of the detection method for a grounding fault in a distribution network are implemented.

[0033] In a fifth aspect, the present disclosure further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the detection method for a grounding fault in a distribution network are implemented.

[0034] The above detection method for a grounding fault in a distribution network has at least the following beneficial effects:

[0035] The embodiment solution provided by the present disclosure performs multi-level synchronous acquisition and encrypted transmission of electrical quantities, and through spatio-temporal two-dimensional analysis, accurately identifies real fault signals, avoiding missed detections caused by weak signals in high-resistance grounding or intermittent faults. Through cross-level linkage, each link responds simultaneously, shortening the fault clearing time to the order of hundreds of milliseconds, and only isolating the fault area, while non-fault users continue to be powered, realizing automatic generation and dynamic adjustment of the restoration path.

[0036] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0038] Figure 1 It is an application environment diagram of the detection method for grounding faults in a distribution network in an embodiment;

[0039] Figure 2 It is a schematic flowchart of the detection method for grounding faults in a distribution network in an embodiment;

[0040] Figure 3 It is a structural block diagram of the detection device for grounding faults in a distribution network in an embodiment;

[0041] Figure 4 It is an internal structure diagram of a computer device in an embodiment;

[0042] Figure 5 It is an internal structure diagram of a server in an embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] In order to enable those of ordinary skill in the art to better understand the technical solutions of the present disclosure, the following will clearly and completely describe the technical solutions in the embodiments of the present disclosure in conjunction with the drawings.

[0044] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present disclosure are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present disclosure described here can be implemented in an order other than those illustrated or described here. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. On the contrary, they are only examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims. The term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, product or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, product or device. Without further limitation, there is no exclusion of additional identical or equivalent elements in the process, method, product or device including the said elements. For example, if the words first, second, etc. are used to represent names, they do not represent any specific order.

[0045] The embodiment of the present disclosure provides a method for detecting grounding faults in a distribution network, which can be applied to an application environment as Figure 1 shown. A multi-level collaborative protection system for grounding faults in a distribution network consists of an intelligent terminal at the substation layer, an intelligent terminal at the line layer, an intelligent terminal at the user side, and a master station collaborative control platform. The intelligent terminal at the substation layer is configured at the neutral point of the distribution network to monitor the zero-sequence voltage and the parameters of the grounding current transformer in real time; the intelligent terminal at the line layer is deployed at the head end of each feeder to synchronously collect three-phase current and voltage and transient high-frequency components; the intelligent terminal at the user side is installed at the important user access point to detect the load current distortion rate and the grounding leakage current; the master station collaborative control platform is connected to the terminals at each level through a high-speed communication network.

[0046] The steps of the master station collaborative control platform include:

[0047] Joint identification of multi-source fault characteristics: Construct a composite criterion by fusing the sudden change of zero-sequence admittance, the entropy value of the transient energy spectrum, and the phase angle difference of the third harmonic;

[0048] Optimization of cross-level disposal strategies: Dynamically generate a multi-mode collaborative scheme based on the network topology, including flexible grounding compensation, active voltage reduction of the fault phase, and interlocking tripping of intelligent switches;

[0049] Distribution of self-healing control instructions: Send parameter setting values and timing control commands to the corresponding level terminals.

[0050] The line - layer terminal includes a transient recording module, a spectrum analysis unit, and an in - situ decision - making logic. The transient recording module captures the initial transient traveling - wave waveform of the fault at a sampling rate of 1 MHz and uses a sparse sampling technique based on compressive sensing to reduce the data storage volume by 60% while ensuring the waveform integrity. The spectrum analysis unit extracts the characteristic quantities in the 0.1 - 10 kHz frequency band through an improved S - transform, and at the same time introduces a convolutional neural network to perform adaptive clustering on the spectrum features to identify atypical fault patterns. The in - situ decision - making logic preferentially activates the small - resistance switching device when a directional grounding signal is detected, and real - time monitors the resistance temperature through a fiber Bragg grating sensor, and dynamically corrects the switching duration in combination with the ambient humidity.

[0051] The joint identification of multi - source fault characteristics specifically includes: establishing a fusion model based on the D - S evidence theory to perform confidence weighting on the zero - sequence voltage mutation rate collected at the substation layer, the transient polarity direction detected at the line layer, and the harmonic impedance change monitored at the user side; introducing a long - short - term memory network (LSTM) to perform time - series modeling on historical fault data to predict the adjustment trend of the dynamic threshold; triggering a cross - level collaborative mechanism when the composite criterion value exceeds the dynamic threshold, and the dynamic threshold is automatically adjusted according to the system operation mode, and the threshold adjustment log is recorded based on blockchain technology to ensure the immutability of the data.

[0052] The master - station collaborative control platform includes a topology - adaptive module, a policy matrix generator, and a decision - making optimization engine based on deep reinforcement learning. The topology - adaptive module is used to real - time analyze the network connection relationship provided by the SCADA system and integrate edge - computing nodes to achieve a millisecond - level response to topology changes. The policy matrix generator is used to store the collaborative action time - series tables of devices at each level under different grounding - fault scenarios, and share the policy matrix with adjacent - area master stations through a federated learning framework to improve the cross - area collaborative efficiency. The decision - making optimization engine based on deep reinforcement learning obtains the optimal disposal strategy through training with historical fault data and embeds a lightweight digital - twin model to real - time verify the feasibility of the strategy.

[0053] In some embodiments of the present disclosure, as Figure 2 shown, a method for detecting grounding faults in a distribution network is provided. In a specific embodiment, the method may include the following steps:

[0054] S202: Obtain the initial fault signal of the distribution network, where the distribution network includes multiple monitoring points.

[0055] The monitoring points of the distribution network may include substation - layer terminals, line - layer terminals, user - side terminals, and master - station collaborative control platforms. Synchronously collect multi - level electrical quantities through each terminal, including at least neutral - point displacement voltage, feeder zero - sequence current, and user - side insulation parameters, and encrypt the data stream using quantum key distribution technology.

[0056] The substation layer terminal acts as a PTP master clock and broadcasts synchronous timing signals to the line layer terminals and user side terminals through an optical fiber channel. The time synchronization error within each terminal's sampling interval is less than 50 nanoseconds. The timing signal embeds a timestamp protocol resistant to quantum attacks. The neutral point displacement voltage measurement uses a differential amplifier circuit with a notch filter to suppress the third harmonic interference, and a graphene-based flexible electrode is used to improve the measurement sensitivity and anti-electromagnetic interference ability.

[0057] S204: Obtain the actual time when the initial fault signal arrives at different monitoring points. When the actual time matches the theoretical time, determine that the initial fault signal is a homologous fault signal. The theoretical time is calculated based on the distance between the different monitoring points and the signal propagation rate.

[0058] When a grounding fault occurs at a certain point in the distribution network, fault signals such as transient traveling waves and zero-sequence current will propagate to the surrounding at a certain speed, and there is a time difference in the arrival time at different monitoring points. By comparing the matching degree between the actual detection time and the theoretical calculation time of each monitoring point, it can be judged whether these signals come from the same fault point. Homologous signals refer to signals whose time difference should strictly match the physical distance between the monitoring points and the signal propagation rate. Non-homologous signals refer to signals whose time difference may not match due to interference or different fault points.

[0059] S206: When there are associated features of the homologous fault signal at at least two monitoring points, determine that the homologous fault signal is a real fault signal. The associated features at least include the features of the electrical quantities detected at different monitoring points being associated.

[0060] Signals detected at a single monitoring point may be misreported due to interference such as lightning strikes and capacitor switching. A real fault needs to trigger physically related features at at least two monitoring points, such as the time difference of the propagation of fault traveling waves and the causal relationship of electrical quantity changes. By analyzing the spatio-temporal correlation and feature consistency of the signals at different levels and different positions of the monitoring points, isolated interference is excluded to ensure the accuracy of fault judgment. When the homologous signal presents the above-mentioned associated features at at least two monitoring points, it is determined as a real fault signal; if only a signal is detected at a single point, or the multi-source signals have no associated features, it is determined as an interference signal.

[0061] In the above detection method for grounding faults in the distribution network, multi-level electrical quantity synchronous acquisition and encrypted transmission accurately identify real fault signals through spatio-temporal two-dimensional analysis, avoiding missed detections caused by weak signals in high-resistance grounding or intermittent faults. Through cross-level linkage, each link responds simultaneously, shortening the fault clearing time to the order of hundreds of milliseconds, and only isolating the fault area while non-faulty users continue to be powered, realizing automatic generation and dynamic adjustment of the restoration path.

[0062] In one embodiment of the present disclosure, the obtaining of the actual times when the initial fault signal arrives at different monitoring points includes:

[0063] Performing complex wavelet transform on the initial fault signal to obtain the transformed waveform;

[0064] Extracting the time corresponding to the extreme point in the waveform as the actual time when the waveform arrives at the monitoring point.

[0065] Performing complex wavelet transform on the transient traveling wave signal when the fault occurs, extracting the modulus maximum points in the waveform as time markers, and these time markers correspond to the exact moments when the traveling wave arrives at different monitoring points. Using the compressive sensing algorithm to repair the missing waveform segments caused by the sampling interval or noise to ensure data integrity. Establishing a mathematical equation based on the physical length of the transmission line and the traveling wave propagation rate to calculate the theoretical value of the time difference between the time markers of different monitoring points and comparing it with the actual measured value.

[0066] In one embodiment of the present disclosure, the obtaining methods for the distances between different monitoring points and the signal propagation rate include:

[0067] Positioning the coordinates of the monitoring points based on satellite, and calculating the distances between the monitoring points based on the coordinates of the monitoring points;

[0068] Obtaining real-time meteorological data, obtaining the corrected dielectric constant based on the real-time meteorological data, and obtaining the signal propagation rate based on the corrected dielectric constant and the speed of light.

[0069] Introducing meteorological data such as temperature and humidity to correct the traveling wave propagation rate, because air humidity will affect the line dielectric constant and thus change the wave speed. At the same time, using satellite timing data to calibrate the geographical location error of the monitoring points to improve the accuracy of the matching model. When the matching degree exceeds 90%, it is determined that these signals come from the same-source fault and other interference signals are excluded.

[0070] In one embodiment of the present disclosure, after determining that the same-source fault signal is a real fault signal, the method further includes:

[0071] Obtaining the monitoring points of the distribution network and starting the collaborative disposal operation, and the monitoring points at least include the substation layer, the line layer, and the user-side energy storage device;

[0072] The collaborative disposal operation includes that the substation layer adjusts the grounding reactance value, the line layer switch performs directional blocking, the user-side energy storage device injects compensation current to assist in arc extinguishing, and reactive power compensation is realized based on the superconducting magnetic energy storage system.

[0073] At least two levels detect associated features such as voltage mutation at the substation layer and abnormal zero-sequence current at the line layer, and it is determined as a real fault to avoid misoperation caused by false alarms of a single device.

[0074] The substation layer can adjust the grounding reactance value, such as putting into arc suppression coils or small resistors, to suppress the overvoltage caused by faults, reduce the neutral point displacement voltage to below 30% of the rated value, and prevent equipment insulation damage.

[0075] The line layer performs directional blocking: determines the fault area through the zero-sequence current direction, prohibits the non-fault line switch from tripping, and avoids large-area power outages caused by traditional "full-line tripping"; inverse-time tripping: dynamically adjusts the switch opening time according to the rising rate of the fault current, the greater the current, the shorter the delay, and at the same time uses silicon carbide semiconductor devices to shorten the opening time to within 2 ms to quickly isolate the fault.

[0076] User side: The energy storage device injects a compensation current to offset the capacitive current at the fault point and assist in extinguishing the arc.

[0077] Injects a reverse voltage into the fault phase through a three-level inverter to reduce the voltage of the fault phase to below 30% of the rated value within 100 ms, and forcibly suppresses the arc reignition.

[0078] In an embodiment of the present disclosure, the method further includes:

[0079] Restores the distribution network path based on a preset two-layer model. The upper layer model of the preset two-layer model generates an initial restoration path based on an improved particle swarm optimization algorithm, and the lower layer model calculates the evaluation index of the initial restoration path based on a quantum annealing algorithm, and selects the initial restoration path corresponding to the first-ranked evaluation index as the new distribution network path.

[0080] Adopts a two-layer model. The upper layer uses an improved particle swarm optimization algorithm to generate possible restoration paths, such as switching to a standby power supply and closing a tie switch; the lower layer uses a quantum annealing algorithm to accelerate the calculation of indicators such as network loss and voltage qualification rate of each path, and selects the path with the optimal comprehensive performance.

[0081] In an embodiment of the present disclosure, before restoring the distribution network path, the method includes:

[0082] Performs a loop closing operation on the distribution network and collects the voltage phase angle difference of the distribution network after loop closing;

[0083] Triggers dynamic reactive power compensation when the voltage phase angle difference exceeds a preset phase angle difference;

[0084] Obtains the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate of the distribution network, calculates the comprehensive index of the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate based on the interval membership function, and restores the distribution network path when the comprehensive index is greater than the preset index.

[0085] When the switch is closed when power is restored, at the moment of loop closing operation, the distributed synchronous phasor measurement unit is used to track the phase angle difference of the feeder nodes in real time. If it is detected that the phase angle difference between adjacent feeders exceeds 5° and lasts for 200 ms, the dynamic reactive power compensation device is triggered to perform phase angle difference damping control; the dynamic reactive power compensation device integrates a superconducting energy storage module to achieve transient power fluctuation suppression; the voltage qualification rate evaluation uses an interval membership function to perform a fuzzy comprehensive evaluation of the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate of each node in the restoration path. When the output comprehensive qualification index is greater than 0.9, the power restoration operation is allowed to be executed, and the parameter weights of the membership function are continuously optimized based on the federated learning framework.

[0086] It should be understood that although the steps in the flowcharts involved in the above-described embodiments are shown in sequence according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-described embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily executed at the same moment, but can be executed at different moments. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or steps or stages in other steps.

[0087] Based on the same inventive concept, an embodiment of the present disclosure also provides a detection device for a distribution network grounding fault for implementing the detection method for a distribution network grounding fault involved above. The implementation solution provided by this device to solve the problem is similar to the implementation solution described in the above method. Therefore, the specific limitations in the embodiment of the detection device for a distribution network grounding fault provided below can refer to the limitations on the detection method for a distribution network grounding fault in the above text, and will not be repeated here.

[0088] The device may include a system (including a distributed system), software (application), module, component, server, client, etc. that uses the method described in the embodiments of this specification and combines the necessary implementation hardware. Based on the same innovative concept, the device in one or more embodiments provided by the embodiments of the present disclosure is as described in the following embodiments. Since the implementation solution of the device to solve the problem is similar to the method, the implementation of the specific device in the embodiments of this specification can refer to the implementation of the foregoing method, and the repeated parts will not be described again. As used below, the term "unit" or "module" can be a combination of software and / or hardware that can achieve a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0089] In one embodiment, asFigure 3 As shown in the figure, a detection device 300 for grounding faults in a distribution network is provided. The device may be the aforementioned server, or a module, component, device, unit, etc. integrated in the server. The device 300 may include:

[0090] An acquisition module 302, configured to acquire an initial fault signal of the distribution network, where the distribution network includes multiple monitoring points;

[0091] A determination module 304, configured to acquire the actual time when the initial fault signal arrives at different monitoring points, and determine that the initial fault signal is a homologous fault signal when the actual time matches the theoretical time, where the theoretical time is calculated based on the distance between the different monitoring points and the signal propagation rate;

[0092] A detection module 306, configured to determine that the homologous fault signal is a real fault signal when the homologous fault signal has associated features at at least two monitoring points, where the associated features at least include the features of the electrical quantities detected at different monitoring points being associated.

[0093] Regarding the device in the above embodiment, the specific manners in which each module performs operations have been described in detail in the embodiment related to the method, and will not be elaborated here.

[0094] Each module in the above detection device for grounding faults in a distribution network may be implemented in whole or in part by software, hardware, and their combination. The above modules may be embedded in the processor in the computer device in hardware form or be independent of the processor, or may be stored in the memory in the computer device in software form, so as to facilitate the processor to call and execute the operations corresponding to the above modules.

[0095] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as Figure 4 shown. The computer device includes a processor, a memory, and a network interface connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store distribution data. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, it implements a method for detecting grounding faults in a distribution network.

[0096] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as Figure 5As shown in the figure. The computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface of the computer device is used to communicate with external terminals in a wired or wireless manner, and the wireless manner can be implemented through WIFI, mobile cellular networks, NFC (Near Field Communication), or other technologies. The computer program, when executed by the processor, implements a method for detecting grounding faults in a distribution network. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covering the display screen, or a button, trackball, or touchpad provided on the outer shell of the computer device, or an external keyboard, touchpad, or mouse, etc.

[0097] Those skilled in the art can understand that Figure 4 , Figure 5 the structure shown in the figure is only a block diagram of some structures related to the solution of the present disclosure, and does not constitute a limitation on the computer device to which the solution of the present disclosure is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0098] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, it implements the method described in any embodiment of the present disclosure.

[0099] In one embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, it implements the method described in any embodiment of the present disclosure.

[0100] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided by the present disclosure can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided by the present disclosure can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided by the present disclosure can be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0101] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0102] The above-described embodiments merely represent several implementation manners of the present disclosure. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present disclosure. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present disclosure, several modifications and improvements can still be made, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the appended claims.

Claims

1. A detection method for grounding faults in a distribution network, characterized in that, The method includes: Obtaining an initial fault signal of the distribution network, where the distribution network includes multiple monitoring points; Obtaining the actual time when the initial fault signal arrives at different monitoring points, and determining the initial fault signal as a homologous fault signal when the actual time matches the theoretical time, where the theoretical time is calculated based on the distance between the different monitoring points and the signal propagation rate; When there are associated features of the homologous fault signal at at least two monitoring points, determining the homologous fault signal as a real fault signal, where the associated features at least include the features of the electrical quantities detected at different monitoring points being associated.

2. The method according to claim 1, wherein The obtaining the actual time when the initial fault signal arrives at different monitoring points includes: Performing complex wavelet transform on the initial fault signal to obtain a transformed waveform; Extracting the time corresponding to the extreme points in the waveform as the actual time when the waveform arrives at the monitoring point.

3. The method according to claim 1, characterized in that, The obtaining method of the distance between the different monitoring points and the signal propagation rate includes: Positioning the coordinates of the monitoring points based on satellites, and calculating the distance between the monitoring points based on the coordinates of the monitoring points; Obtaining real-time meteorological data, obtaining a corrected dielectric constant based on the real-time meteorological data, and obtaining the signal propagation rate based on the corrected dielectric constant and the speed of light.

4. The method according to claim 1, characterized in that, After determining that the homologous fault signal is a real fault signal, the method further includes: Obtaining the monitoring points of the distribution network and starting a collaborative disposal operation, where the monitoring points at least include a substation layer, a line layer, and a user-side energy storage device; The collaborative disposal operation includes that the substation layer adjusts the grounding reactance value, the line layer switch performs directional blocking, the user-side energy storage device injects a compensation current to assist in arc extinguishing, and reactive power compensation is realized based on a superconducting magnetic energy storage system.

5. The method according to claim 4, wherein The method further includes: Restoring the distribution network path based on a preset two-layer model, where the upper layer model of the preset two-layer model generates an initial restoration path based on an improved particle swarm algorithm, the lower layer model calculates an evaluation index of the initial restoration path based on a quantum annealing algorithm, and selects the initial restoration path corresponding to the first-ranked evaluation index as the new distribution network path.

6. The method according to claim 5, wherein Before restoring the distribution network path, the method includes: Performing a loop closing operation on the distribution network and collecting the voltage phase angle difference of the distribution network after loop closing; When the voltage phase angle difference exceeds a preset phase angle difference, triggering dynamic reactive power compensation; Obtaining the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate of the distribution network, calculating a comprehensive index of the voltage deviation rate, three-phase unbalance degree, and harmonic distortion rate based on an interval membership function, and restoring the distribution network path when the comprehensive index is greater than a preset index.

7. A detection device for grounding faults in a distribution network, characterized in that, The device includes: An obtaining module, configured to obtain an initial fault signal of the distribution network, where the distribution network includes multiple monitoring points; A determining module, configured to obtain the actual time when the initial fault signal arrives at different monitoring points, and determine the initial fault signal as a homologous fault signal when the actual time matches the theoretical time, where the theoretical time is calculated based on the distance between the different monitoring points and the signal propagation rate; A detection module, configured to determine the homologous fault signal as a true fault signal when there are associated features of the homologous fault signal at at least two monitoring points, where the associated features at least include features of the electrical quantities detected at different monitoring points being associated.

8. A detection system for grounding faults in a distribution network, characterized in that, The system includes: A substation layer terminal, configured at the neutral point of the distribution network, for real-time monitoring of zero-sequence voltage and earthing converter parameters; A line layer terminal, configured at the head end of each feeder of the distribution network, for synchronously collecting three-phase current and voltage and transient high-frequency components; A user side terminal, configured at a critical user access point, for detecting the load current distortion rate and the earth leakage current; A master station collaborative control platform, connected to each terminal.

9. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the method according to any one of claims 1 to 6.

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