Method and system for quickly positioning, isolating and recovering grounding fault of power distribution network

Abstract

The invention provides a power distribution network grounding fault rapid positioning, isolation and recovery method and system, and relates to the technical field of power system fault detection, and the method comprises the steps: dividing a power distribution line interval segment between two adjacent node switches into monitoring units through each node switch on a power distribution network line; the method comprises the following steps: synchronously acquiring power grid quantity data, switch state information, fault signals and fault event processing information through a power distribution terminal by utilizing a wide-area synchronization method of Beidou clock signals; fault monitoring is carried out, and a fault monitoring result is synchronized to all the power distribution terminals; a multi-point zero-sequence current analysis method is utilized to position a grounding fault interval; the upstream power distribution terminal, the downstream power distribution terminal and the switch equipment of the grounding fault interval are used for isolating the grounding fault area; and recovering the power supply of the non-grounding fault section. The automation level and the management level of the power distribution network are improved, and the maintenance cost of the power distribution network is reduced.

Description

Technical Field

[0001] The present invention relates to the field of power system fault detection technology and power distribution automation technology, and in particular to a method and system for quickly locating, isolating and restoring a ground fault in a distribution network. Background Art

[0002] As the end of the power system, the distribution network is directly connected to the users. It is responsible for reducing the electric energy transmitted by the high-voltage transmission lines into medium and low voltage electric energy suitable for users through transformers, and distributing it to end users. It is the link in the power system that is most closely connected with users. The distribution network lines are characterized by large scale, wide coverage, diverse geographical environment, complex grid structure, numerous line branches, complex equipment, and a large number of users.

[0003] The distribution network is affected by the operating environment, power load, equipment aging, user capacity expansion, distributed power supply access, climate and environmental changes, external force damage and urban construction. Failures often occur in the distribution network, and power outages are relatively frequent, seriously affecting the reliability of power supply and the safety and stability of grid operation.

[0004] However, the existing ground fault recovery method does not have an accurate time benchmark, the distribution network may fail, the fault detection efficiency is too low, the fault location and isolation process takes a long time, the fault is not handled in time, and the fault range is expanded. When performing fault detection, the detection effect of high-resistance ground faults is poor, and it is difficult to achieve accurate isolation and power supply restoration. There is a fault detection dead zone, and the fault area is not accurately located, resulting in poor power supply quality and low reliability of the distribution network. Summary of the invention

[0005] In order to solve the technical problems that the existing ground fault recovery method has no accurate time reference, the distribution network may leak faults, the fault detection efficiency is too low, the fault location and isolation process takes a long time, the fault is not handled in time, the fault range is expanded, and the detection effect of high-resistance ground faults is poor during fault detection, it is difficult to achieve accurate isolation and power supply restoration, there is a fault detection dead zone, the fault area is inaccurately located, resulting in poor power supply quality and low reliability of the distribution network, the present invention provides a distribution network ground fault rapid location, isolation and recovery method and system.

[0006] The technical solution provided by the embodiment of the present invention is as follows:

[0007] First aspect:

[0008] An embodiment of the present invention provides a method for quickly locating, isolating and restoring a ground fault in a distribution network, comprising:

[0009] S1: Divide the distribution line section between two adjacent node switches into monitoring units through each node switch on the distribution network line, wherein the monitoring unit includes distribution terminals and switch devices on both sides of the distribution line section;

[0010] S2: Through the power distribution terminal, using the wide area synchronization method of the Beidou clock signal, synchronously collect power grid quantity data, switch status information, fault signals and fault event processing information;

[0011] S3: performing fault monitoring according to the grid quantity data, the switch status information, the fault signal and the fault event processing information, and synchronizing the fault monitoring result to all power distribution terminals;

[0012] S4: Use multi-point zero-sequence current analysis method to locate the ground fault interval;

[0013] S5: isolating the ground fault area by using the upstream power distribution terminal, the downstream power distribution terminal and the switch equipment in the ground fault area respectively;

[0014] S6: Restore power supply to the non-ground fault section.

[0015] Second aspect:

[0016] An embodiment of the present invention provides a system for quickly locating, isolating and restoring a ground fault in a distribution network, comprising:

[0017] processor;

[0018] A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are executed by the processor, the method for quickly locating, isolating and restoring a ground fault in a distribution network as described in the first aspect is implemented.

[0019] The third aspect:

[0020] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the method for quickly locating, isolating and restoring a ground fault in a distribution network as described in the first aspect is implemented.

[0021] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0022] In an embodiment of the present invention, a wide-area synchronization method of Beidou clock signals is used to realize simultaneous fault collection of all distribution terminals on the distribution network line, thereby ensuring that the fault signal collection data of the distribution terminal is accurate and effective, and improving the accuracy of ground fault positioning. Through a multi-point zero-sequence current analysis method, the ground fault interval can be quickly and accurately located, which significantly improves the detection and positioning effect of high-resistance ground faults and enhances the efficiency of fault handling. By isolating the ground fault area, it can ensure that the power supply of the non-fault interval is restored as soon as possible, reduce the power outage duration of users, and improve the power supply quality and reliability of the distribution network. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic diagram of a flow chart of a method for quickly locating, isolating and restoring a ground fault in a distribution network provided by an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a distribution line grid structure provided by an embodiment of the present invention;

[0026] Figure 3 A schematic diagram of a wide-area synchronous phasor measurement function of a power distribution terminal provided in an embodiment of the present invention;

[0027] Figure 4 A schematic diagram of the structure of a system for quickly locating, isolating and restoring ground faults in a distribution network provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0029] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0030] In the embodiments of the present invention, "image" and "picture" can sometimes be used interchangeably. It should be noted that when the difference between them is not emphasized, the meanings they intend to express are the same. "of", "corresponding, relevant" and "corresponding" can sometimes be used interchangeably. It should be noted that when the difference between them is not emphasized, the meanings they intend to express are the same.

[0031] In the embodiments of the present invention, sometimes a subscript such as W1 may be written as a non-subscript such as W1. When the difference is not emphasized, the meanings to be expressed are the same.

[0032] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0033] Reference Manual Attached Figure 1 , shows a flow chart of a method for quickly locating, isolating and restoring a ground fault in a distribution network provided by an embodiment of the present invention.

[0034] Reference Manual Attached Figure 2 , showing a schematic diagram of a distribution line grid structure provided by an embodiment of the present invention.

[0035] like Figure 2, which is one of the typical application scenarios of the technical solution of the present invention. In the figure, the section switches, connecting switches, branch switches, boundary switches, and each group of switches in the switch cabinet of the distribution line must be equipped with distribution terminals with wide-area synchronous phasor measurement technology, small current signal feature extraction technology, high-speed networking communication technology, multi-point zero-sequence current analysis technology, and neighborhood FA protection technology. In the figure, the distributed power source DG is connected to the grid-connected switch BW01 to provide power to the distribution network. Substation 1, substation 2 and substation 3 are connected to the distribution network through the outgoing line switches CB1, CB2 and CB3 respectively. The power is transmitted to user 1, user 2, and user 3 through the substation. Each user is connected to the boundary switch (FJ101, FJ102, FJ201), and the section switch (FD101, F102, FD 103, FD201) divides the distribution network into multiple areas. Each branch line has a corresponding branch switch (FZ101, FZ201, FZ202) to isolate and protect the circuit. The connecting switches LL12 and LL13 are switches connecting different areas to protect the operation of the entire distribution network. Switch boxes 1, 2, and 3 control different areas and branches respectively. There are multiple section switches (FD104, FD202, FD203, FD302, FD303) and branch switches (FZ102, FZ103, FZ104, FZ105, FZ203, FZ204, FZ205, FZ206, FZ301, FZ302, FZ303, FZ304) under each switch box to finely control the flow and distribution of current.

[0036] An embodiment of the present invention provides a method for quickly locating, isolating and restoring a ground fault in a distribution network, the method comprising:

[0037] S1: The distribution line section between two adjacent node switches is divided into monitoring units through each node switch on the distribution network line, wherein the monitoring unit includes distribution terminals and switch devices on both sides of the distribution line section.

[0038] It should be noted that by dividing the distribution lines into monitoring units, a clear segmented management structure is formed. Each monitoring unit independently collects and processes data, which significantly improves the accuracy of fault location, reduces the impact of the fault range, and facilitates rapid isolation of the faulty section.

[0039] Reference Manual Attached Figure 3 , showing a schematic diagram of the wide-area synchronous phasor measurement function of a distribution terminal provided in an embodiment of the present invention.

[0040] like Figure 3, showing that the clock signal provided by the Beidou satellite is used for data acquisition and processing at the distribution terminal. The Beidou receiving module receives the Beidou signal and performs frequency calibration through the pulse per second (PPS) signal and the timer of the main control chip to ensure the accuracy of multi-channel synchronous sampling. The collected power grid data (such as voltage, current, etc.) is converted into A / D through the SAR ADC chip, and then a digital signal is generated through the signal acquisition and processing unit to provide high-precision power grid phasor measurement results. The entire process ensures time synchronization and data accuracy, providing support for distribution network fault monitoring and analysis.

[0041] S2: Through the power distribution terminal, using the wide-area synchronization method of the Beidou clock signal, the power grid quantity data, switch status information, fault signals and fault event processing information are synchronously collected.

[0042] Among them, the Beidou clock signal is a high-precision clock synchronization signal provided by the Beidou satellite navigation system, which is used to provide a unified time reference for distribution terminals. The wide area synchronization method is a time synchronization method based on the Beidou clock signal, which enables multiple distributed devices to maintain consistency at the millisecond or even microsecond level. The power grid quantity data is the core parameters of the distribution network operation status, including voltage, current, frequency, zero-sequence voltage, zero-sequence current, etc. The fault event processing information is the fault type, fault location, switch action and other processing process related information recorded by the distribution network when a fault occurs.

[0043] It should be noted that through the wide-area synchronization technology of Beidou clock signals, this step achieves high-precision time alignment of data collection between distribution terminals, solving the data error problem caused by time asynchrony of multiple devices in traditional technologies. At the same time, it ensures the real-time and consistency of fault signals and event processing information, improves the accuracy and response speed of fault monitoring, and provides reliable data support for subsequent fault location and isolation. This synchronization technology can also adapt to the complex operating environment of distributed power grids and significantly improve the intelligence and reliability of distribution systems.

[0044] In a possible implementation manner, the grid quantity data includes: voltage, current, frequency, zero-sequence voltage and zero-sequence current of the distribution terminal.

[0045] Among them, zero-sequence voltage refers to the zero-sequence component when the three-phase voltage is unbalanced in a three-phase power system, which is usually caused by a ground fault or asymmetric operation of the three phases. The monitoring of zero-sequence voltage is an important basis for high-resistance ground fault detection. Zero-sequence current refers to the zero-sequence current component in a three-phase power system, which is the sum of the three-phase current vectors. It usually occurs in the case of a ground fault or asymmetric load. The zero-sequence current is used for fault location, which is especially important in ground fault monitoring.

[0046] In a possible implementation, the power distribution terminal includes a Beidou receiving module.

[0047] S2 specifically includes:

[0048] S201: Receive the pulse-per-second signal of the Beidou system using the Beidou receiving module.

[0049] Among them, the Beidou receiving module is a device installed in the power distribution terminal, which is used to receive the clock signal and positioning information transmitted by the Beidou satellite system and provide a high-precision time reference. The pulse per second signal (PPS) is a high-precision time signal sent by the Beidou satellite system. It generates a synchronization pulse every second as a reference signal for clock synchronization.

[0050] It should be noted that using the Beidou receiving module to receive second pulse signals can provide high-precision time synchronization for the distribution terminal, ensuring the consistency of data collection time between multiple terminals, thereby improving the accuracy and real-time performance of fault monitoring and positioning.

[0051] S202: triggering a timer through the main control chip of the power distribution terminal, and measuring the number of timer pulses of adjacent second pulse signals.

[0052] Among them, the main control chip is the core processor in the distribution terminal, which is used to perform functions such as data acquisition, control and fault handling. The timer is a timing module built into the main control chip, which is used to measure time intervals or generate timing signals. The number of pulses is the number of timing pulses output by the clock chip recorded by the timer between two second pulse signals, which is used to calculate the time interval.

[0053] It should be noted that the number of pulses between adjacent second pulse signals is recorded by the timer, and the actual time interval is accurately measured, so as to facilitate the calibration of the clock frequency.

[0054] S203: Calculate the actual output frequency of the power distribution terminal according to the number of timer pulses:

[0055]

[0056] Among them, f r It indicates the actual output frequency of the power distribution terminal's power grid signal acquisition chip, n indicates the number of bits of the timer, G indicates the number of timer overflow restarts, W 1 and W 2 represents the timer count value corresponding to the adjacent second pulse signal. P Indicates the frequency multiplication factor.

[0057] S204: Using the pulse per second signal as the reference time signal, adjust the actual output frequency:

[0058]

[0059] Among them, f MrIt indicates the actual output frequency of the power distribution terminal when M pulse-per-second signals are collected, and M indicates the total number of pulse-per-second signals collected.

[0060] S205: According to the adjusted actual output frequency, synchronously collect power grid quantity data, switch status information, fault signal and fault event processing information.

[0061] In a possible implementation manner, the timing duration of the timer is specifically:

[0062]

[0063] Among them, t n Indicates the timing duration of the timer, n indicates the number of bits of the timer, and f osc represents the nominal clock frequency of the power distribution terminal, P represents the frequency multiplication factor, m represents a natural number, and f k represents the grid quantity sampling frequency of the grid quantity signal acquisition chip of the power distribution terminal, k represents the relationship coefficient, and f n Indicates the nominal frequency of the distribution network.

[0064] Specifically, the grid quantity sampling point values ​​of mainstream distribution terminals in my country are generally 128 or 256. As shown in Table 1, the corresponding relationships and recommended suggestions of the above parameters when the sampling points are 64 to 1024 are listed:

[0065] Table 1

[0066]

[0067] As shown in Table 1, it provides an optimization selection reference for the design and practical application of distribution network terminals.

[0068] In the present invention, a wide-area synchronization method of Beidou clock signals is used. Under the condition of stable satellite signal communication, the Beidou receiving module of the distribution terminal generates a high-precision pulse-per-second signal (PPS). The time deviation of the PPS signal does not exceed 10 nanoseconds and there is no error accumulation. The PPS signal is used as the reference time signal. The main control chip of the distribution terminal controls the sampling interval of the power grid quantity collection chip (SAR-type ADC chip) through a timer. The power grid quantity collection chip with an adaptive PPS signal is used to calibrate the collection time to ensure that all distribution terminals are sampled at the same time and frequency, thereby realizing the wide-area synchronous power grid quantity collection function of multiple distribution terminals. The absolute time (Beidou time) error of the synchronous sampling is at the microsecond level.

[0069] S3: Perform fault monitoring based on grid quantity data, switch status information, fault signals and fault event processing information, and synchronize the fault monitoring results to all distribution terminals.

[0070] It should be noted that by comprehensively analyzing grid data, switch status information, fault signals and fault event processing information, accurate fault monitoring can be achieved and the monitoring results can be synchronized to all distribution terminals. This synchronization mechanism not only improves the efficiency of fault information sharing, but also significantly reduces the time for fault location and isolation, thereby improving the system's response speed and power supply reliability.

[0071] In a possible implementation, the fault monitoring result includes: power grid quantity data and a fault signal of the power distribution terminal at the time of the fault.

[0072] S3 specifically includes:

[0073] When the fault signal reaches a preset threshold, the grid quantity data and fault signal of the distribution terminal at the time of the fault are collected, and the grid quantity data and fault signal of the distribution terminal at the time of the fault are sent to each distribution terminal using a high-speed networking communication system.

[0074] S4: Use the multi-point zero-sequence current analysis method to locate the ground fault interval.

[0075] Among them, the multi-point zero-sequence current analysis method is a method for determining the fault location by monitoring the zero-sequence current signals of multiple nodes in the distribution network. The zero-sequence current is the vector sum of the three-phase currents and is used to detect ground faults or line asymmetry problems. The ground fault interval refers to the specific location or range where a ground fault occurs in the distribution line.

[0076] It should be noted that through the multi-point zero-sequence current analysis method, the multi-node zero-sequence current signals collected by the distribution terminal can be used to achieve high-precision ground fault location, overcoming the limitations of traditional single-point detection, and can accurately identify weak characteristic faults such as high-resistance ground faults, thereby improving the accuracy and efficiency of fault location.

[0077] In a possible implementation, S4 specifically includes:

[0078] S401: Determine the location of the fault point by comparing the transient zero-mode zero-sequence current of each distribution terminal:

[0079]

[0080] Where ρ represents the correlation coefficient of zero-sequence current detected by two adjacent distribution terminals, i 01 and i 02 They represent the transient zero-mode zero-sequence current collected by two adjacent distribution terminals, n represents the sampling value of the transient zero-mode zero-sequence current signal, , N represents the data length of the transient zero-mode zero-sequence current signal;

[0081] S402: Accurately locate the fault area according to the position of the fault point.

[0082] S5: Isolate the ground fault area by using the upstream distribution terminal, downstream distribution terminal and switch equipment in the ground fault area.

[0083] It should be noted that by coordinating the upstream distribution terminals, downstream distribution terminals and switchgear, the grounding fault area can be accurately isolated to avoid the expansion of the fault impact range. The fault area can be isolated quickly and automatically, the power outage scope can be reduced, and the normal power supply of the non-fault area can be protected.

[0084] In a possible implementation, S5 specifically includes:

[0085] A monitoring unit that uses the upstream distribution terminal to locate the ground fault.

[0086] After the switch device of the monitoring unit is reclosed, the ground fault disappears. The ground fault is a transient ground fault, the fault is eliminated, and the transient ground fault processing information and switch action event record are uploaded to the power distribution master station system.

[0087] Among them, instantaneous ground fault refers to a short-term ground fault caused by temporary external reasons.

[0088] If the ground fault is a permanent ground fault, after the switch device of the monitoring unit is reclosed, the upstream distribution terminal detects the ground fault signal again, the switch device trips and locks again to isolate the fault area, and uploads the permanent ground fault processing information and switch action event record to the distribution master station system.

[0089] Among them, a permanent ground fault refers to a ground fault that persists and needs to be resolved by isolating the fault section and other operations.

[0090] The monitoring unit where the ground fault occurs is located using the downstream distribution terminal.

[0091] When the monitoring unit loses power for the first time, the downstream distribution terminal does not control the opening and closing of the switch.

[0092] If there is no power failure within the call confirmation time after the first power failure, the ground fault is a transient ground fault, the fault is eliminated, and the downstream distribution terminal does not control the opening and closing actions of the corresponding switch device.

[0093] If power is lost again within the call confirmation time after the first power loss, the downstream distribution terminal will immediately control the corresponding switch equipment to trip, lock and close, isolate the fault area, and upload the permanent grounding fault processing information and switch action event record to the distribution master station system.

[0094] S6: Restore power supply to the non-ground fault section.

[0095] The non-ground fault section refers to the normal working area in the distribution line that is not affected by the ground fault, usually referring to the power supply section outside the fault point.

[0096] It should be noted that by quickly restoring power supply to the non-grounding fault area, the power outage time for users is effectively shortened, the reliability and stability of the power supply service is improved, the problem of long-term power outages in non-fault areas due to fault isolation is avoided, and the impact of fault handling on the normal power supply area is reduced.

[0097] In a possible implementation, S6 specifically includes:

[0098] S601: Each distribution terminal downstream of the non-ground fault does not control the switch opening and closing actions when the power is lost for the first time.

[0099] Among them, the first power outage refers to the first power interruption caused by a fault that leads to a regional power outage.

[0100] It should be noted that not controlling the opening and closing actions of the switches during the first power failure can effectively avoid misoperation and prevent unnecessary power outages or equipment losses in non-fault areas due to erroneous operations, thereby improving the stability of grid operation and control accuracy.

[0101] S602: If there is no power failure within the call confirmation time after the first power failure, the ground fault is a transient ground fault, the fault is eliminated, and the downstream distribution terminal does not control the opening and closing actions of the corresponding switch equipment. If there is a power failure within the call confirmation time after the first power failure, the downstream distribution terminal controls the closing of the interconnecting switch and does not control the opening and closing actions of other switches to restore power supply to the non-fault section.

[0102] Among them, the call confirmation time refers to the time interval used to observe whether the power is restored after the first power outage. It is used to distinguish between transient faults and permanent faults, and usually can be restored without further processing. The interconnecting switch refers to the switching device that connects the non-fault area with the backup power supply or other lines. The power supply of the non-fault area is restored by closing it.

[0103] It should be noted that the nature of the fault is judged by the call confirmation time, unnecessary operations are avoided in transient faults, and the number of equipment actions is reduced. For permanent faults, power supply to non-fault sections is restored by controlling the closing of the interconnecting switch, narrowing the scope of power outages and improving power supply reliability, which not only reduces the impact on the power grid but also improves the efficiency of power supply restoration.

[0104] In the present invention, the neighborhood FA protection action principle is used to realize the rapid processing and isolation of the ground fault, and the distribution terminal control switch in the non-fault area is tripped or closed to quickly restore the power supply to the non-fault area. The neighborhood FA protection action principle is specifically as follows:

[0105] (1) The distribution terminal locates the ground fault section for the first time. The distribution terminal on the upstream side of the ground fault section controls the switch to trip and reclose. After the switch is reclosed, the ground fault disappears. It is a transient ground fault and the fault has been eliminated. After the switch is reclosed, the distribution terminal detects the ground fault again. It is a permanent ground fault. The switch reclosing fails. The distribution terminal controls the switch to trip and lock again to isolate the faulty section.

[0106] (2) When the first power failure occurs in the downstream distribution terminal of the ground fault section, the switch is not controlled to trip. If there is no power failure again within the call confirmation time after the first power failure, it is a momentary ground fault and the fault has been eliminated. The distribution terminal does not control or operate the switch. If there is a power failure again within the call confirmation time after the first power failure, the switch is immediately controlled to trip and lock and close to isolate the faulty section.

[0107] (3) The distribution terminals in the non-fault area downstream of the ground fault section do not control the switch tripping or closing action when the first power outage occurs. If there is no power outage again within the call confirmation time after the first power outage, it is a momentary ground fault and the fault has been eliminated. The distribution terminals do not control the switch opening and closing action. If there is power outage again within the call confirmation time after the first power outage, the distribution terminals only control the closing of the interconnecting switch and do not control the opening and closing actions of other switches (specifically: section switches, branch switches, and boundary switches in the downstream non-fault area) to restore power supply to the non-fault area.

[0108] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0109] In an embodiment of the present invention, by extracting the traffic characteristics, load characteristics and timing characteristics of network data, the rich information contained therein is fully mined, and a multiple attention mechanism is introduced to dynamically identify the importance of each feature, thereby improving the expressive power of the features, being able to capture complex attack patterns, and improving the accuracy of network attack detection, thereby reducing the occurrence of false positives and negatives.

[0110] Reference Manual Attached Figure 4 , showing a schematic structural diagram of a distribution network ground fault rapid location, isolation and restoration system provided by the present invention.

[0111] The present invention further provides a distribution network ground fault rapid location, isolation and restoration system 20, which is applied to the above-mentioned distribution network ground fault rapid location, isolation and restoration method, comprising:

[0112] Processor 201.

[0113] The memory 202 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 201, a method for quickly locating, isolating and restoring a ground fault in a distribution network as described in the method embodiment is implemented.

[0114] The distribution network ground fault rapid location, isolation and restoration system 20 provided by the present invention can execute the above-mentioned distribution network ground fault rapid location, isolation and restoration method, and achieve the same or similar technical effects. To avoid repetition, the present invention will not go into details.

[0115] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0116] In an embodiment of the present invention, by extracting the traffic characteristics, load characteristics and timing characteristics of network data, the rich information contained therein is fully mined, and a multiple attention mechanism is introduced to dynamically identify the importance of each feature, thereby improving the expressive power of the features, being able to capture complex attack patterns, and improving the accuracy of network attack detection, thereby reducing the occurrence of false positives and negatives.

[0117] It should be understood that the processor in the embodiment of the present invention may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0118] It should also be understood that the memory in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0119] The above embodiments can be implemented in whole or in part by software, hardware (such as circuits), firmware or any other combination. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When a computer instruction or computer program is loaded or executed on a computer, a process or function according to an embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0120] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0121] In the present invention, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0122] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0123] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0124] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described equipment, devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0125] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0126] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0127] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0128] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0129] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, a method for quickly locating, isolating and restoring a ground fault in a distribution network as described in a method embodiment is implemented.

[0130] A computer-readable storage medium provided by the present invention can implement the steps and effects of the method for quickly locating, isolating and restoring grounding faults in a distribution network of the above method embodiment. To avoid repetition, the present invention will not go into details.

[0131] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0132] In an embodiment of the present invention, by extracting the traffic characteristics, load characteristics and timing characteristics of network data, the rich information contained therein is fully mined, and a multiple attention mechanism is introduced to dynamically identify the importance of each feature, thereby improving the expressive power of the features, being able to capture complex attack patterns, and improving the accuracy of network attack detection, thereby reducing the occurrence of false positives and negatives.

[0133] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0134] There are a few points to note:

[0135] (1) The drawings of the embodiments of the present invention only involve structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0136] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness of layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0137] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0138] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for quickly locating, isolating and restoring a ground fault in a distribution network, characterized in that: include: S1: Divide the distribution line section between two adjacent node switches into monitoring units through each node switch on the distribution network line, wherein the monitoring unit includes distribution terminals and switch devices on both sides of the distribution line section; S2: Through the power distribution terminal, using the wide area synchronization method of the Beidou clock signal, synchronously collect power grid quantity data, switch status information, fault signals and fault event processing information; S3: performing fault monitoring according to the grid quantity data, the switch status information, the fault signal and the fault event processing information, and synchronizing the fault monitoring result to all power distribution terminals; S4: Use multi-point zero-sequence current analysis method to locate the ground fault interval; S5: isolating the ground fault area by using the upstream distribution terminal, the downstream distribution terminal and the switch equipment in the ground fault area respectively; S6: Restore power supply to the non-ground fault section.

2. The method for quickly locating, isolating and restoring a ground fault in a distribution network according to claim 1, characterized in that: The power grid quantity data includes: voltage, current, frequency, zero-sequence voltage and zero-sequence current of the power distribution terminal.

3. The method for rapid location, isolation and restoration of ground fault in distribution network according to claim 1, characterized in that: The power distribution terminal includes a Beidou receiving module; The S2 specifically includes: S201: Receive a pulse-per-second signal of a BeiDou system using the BeiDou receiving module; S202: The main control chip of the power distribution terminal triggers a timer and measures the number of timer pulses of adjacent second pulse signals; S203: Calculate the actual output frequency of the power distribution terminal according to the timer pulse number: ； Among them, f r It indicates the actual output frequency of the power distribution terminal's power grid signal acquisition chip, n indicates the number of bits of the timer, G indicates the number of timer overflow restarts, W 1 and W 2 represents the timer count value corresponding to the adjacent second pulse signal. P represents the frequency multiplication factor; S204: Using the pulse-per-second signal as a reference time signal, adjusting the actual output frequency: ； Among them, f Mr It indicates the actual output frequency of the power distribution terminal when M pulse-per-second signals are collected, where M indicates the total number of pulse-per-second signals collected; S205: According to the adjusted actual output frequency, synchronously collect power grid quantity data, switch status information, fault signal and fault event processing information.

4. The method for quickly locating, isolating and restoring a ground fault in a distribution network according to claim 3, characterized in that: The specific timing duration of the timer is: ； Among them, t n Indicates the timing duration of the timer, n indicates the number of bits of the timer, and f osc represents the nominal clock frequency of the power distribution terminal, P represents the frequency multiplication factor, m represents a natural number, and f k represents the grid quantity sampling frequency of the grid quantity signal acquisition chip of the power distribution terminal, k represents the relationship coefficient, and f n Indicates the nominal frequency of the distribution network.

5. The method for rapid location, isolation and restoration of ground fault in distribution network according to claim 1, characterized in that: The fault monitoring result includes: the power grid quantity data and fault signal of the power distribution terminal at the time of the fault; The S3 specifically includes: When the fault signal reaches a preset threshold, the grid quantity data and fault signal of the distribution terminal at the time of the fault are collected, and the grid quantity data and fault signal of the distribution terminal at the time of the fault are sent to each distribution terminal using a high-speed networking communication system.

6. The method for rapid location, isolation and restoration of ground fault in distribution network according to claim 1, characterized in that: The S4 specifically includes: S401: Determine the location of the fault point by comparing the transient zero-mode zero-sequence current of each distribution terminal: ； Where ρ represents the correlation coefficient of zero-sequence current detected by two adjacent distribution terminals, i 01 and i 02 They represent the transient zero-mode zero-sequence current collected by two adjacent distribution terminals, n represents the sampling value of the transient zero-mode zero-sequence current signal, , N represents the data length of the transient zero-mode zero-sequence current signal; S402: Accurately locate the fault area according to the position of the fault point.

7. The method for rapid location, isolation and restoration of ground fault in distribution network according to claim 1, characterized in that: The S5 specifically includes: A monitoring unit for locating a ground fault occurrence using the upstream power distribution terminal; After the switch device of the monitoring unit is reclosed, the ground fault disappears, the ground fault is a transient ground fault, the fault is eliminated, and the processing information of the transient ground fault and the switch action event record are uploaded to the power distribution master station system; If the ground fault is a permanent ground fault, after the switch device of the monitoring unit is reclosed, the upstream power distribution terminal detects the ground fault signal again, and the switch device trips and closes again to isolate the fault area, and uploads the permanent ground fault processing information and switch action event record to the power distribution master station system; locating a monitoring unit where a ground fault occurs using the downstream power distribution terminal; When the monitoring unit loses power for the first time, the downstream power distribution terminal does not control the opening and closing actions of the switch; If there is no power failure again within the call confirmation time after the first power failure, the ground fault is a transient ground fault, the fault is eliminated, and the downstream power distribution terminal does not control the opening and closing actions of the corresponding switch device; If power is lost again within the call confirmation time after the first power loss, the downstream distribution terminal immediately controls the corresponding switch equipment to trip, lock and close, isolate the fault area, and upload the permanent ground fault processing information and switch action event record to the distribution master station system.

8. The method for rapid location, isolation and restoration of ground fault in distribution network according to claim 1, characterized in that: The S6 specifically includes: S601: Each distribution terminal downstream of the non-ground fault does not control the switch opening and closing actions when the power fails for the first time; S602: If there is no power failure again within the call confirmation time after the first power failure, the ground fault is a transient ground fault and the fault is eliminated. The downstream power distribution terminal does not control the opening and closing actions of the corresponding switch equipment. If there is a power failure again within the call confirmation time after the first power failure, the downstream power distribution terminal controls the closing of the interconnecting switch and does not control the opening and closing actions of other switches to restore power supply to the non-fault section.

9. A distribution network ground fault rapid location, isolation and restoration system, characterized in that: include: processor; A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are executed by the processor, the method for quickly locating, isolating and restoring a ground fault in a distribution network as claimed in any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for quickly locating, isolating and restoring a ground fault in a distribution network as described in any one of claims 1 to 8 is implemented.

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