Ground fault identification method and system based on multi-dimensional collaborative monitoring

Abstract

The present disclosure provides a ground fault identification method and system based on multi-dimensional collaborative monitoring, including: real-time acquisition of the sent signal of the small current grounding line selection device; based on the type of the sent signal, obtaining the rough location of the ground fault; when determining the distribution line where the fault is located, based on the zero-sequence current alarm information uploaded by all intelligent devices on the current distribution line, determining the precise location of the ground fault; when only the bus section where the fault is located is determined, obtaining all distribution lines of the current bus section, respectively screening the zero-sequence current alarm information of the first intelligent device on different distribution lines, and determining the precise location of the ground fault based on the zero-sequence current alarm information. The scheme greatly reduces the fault finding time, improves the power supply reliability, and especially improves the personal safety factor of the repair personnel when a fault occurs in severe weather.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network fault processing, and in particular to a ground fault identification method and system based on multi-dimensional collaborative monitoring. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.

[0003] Single-phase grounding faults in 10kV distribution lines account for a relatively high proportion of distribution network faults. When a single-phase grounding fault occurs, it will cause intermittent isolated light grounding, resulting in resonant overvoltage, further causing insulation breakdown, causing phase-to-phase short circuits, and may also cause equipment damage, affecting power supply reliability.

[0004] The inventors have found that in order to realize the identification of single-phase grounding faults in the distribution network, the traditional grid segmentation method and the line pulling test method are still widely used. For substations equipped with a small current grounding line selection device, the small current grounding line selection device is mainly used to narrow the grounding fault to the distribution line level, and then the equipment management unit conducts line patrol and search until the fault point is found; when the small current grounding line selection device fails to select the line correctly, it can only be narrowed to the busbar section, which is not very helpful for fault finding, and the line pulling test method can only be used; especially for substations without a small current grounding line selection device, when dealing with grounding faults, there is only one method, the line pulling test, and the line pulling test requires at least two people to perform, and is time-consuming and labor-intensive, and cannot effectively guarantee the safety of personnel. Obviously, it is impossible to quickly and accurately identify grounding faults by relying solely on the main network small current grounding line selection device. Summary of the invention

[0005] In order to solve the above problems, the present disclosure provides a ground fault identification method and system based on multi-dimensional collaborative monitoring. The scheme is based on the information uploaded by the small current grounding line selection device and combined with the information collected by the intelligent equipment of the distribution automation master station. It can quickly and accurately identify the ground fault. At the same time, the safety of the detection personnel is effectively guaranteed through automated identification.

[0006] According to a first aspect of an embodiment of the present disclosure, a ground fault identification method based on multi-dimensional collaborative monitoring is provided, comprising:

[0007] Obtain the uplink signal of the small current grounding line selection device in real time;

[0008] Based on the type of the sent signal, a rough position of the ground fault is obtained;

[0009] When the distribution line where the fault is located is determined, the precise location of the ground fault is determined based on the zero-sequence current alarm information uploaded by all intelligent devices on the current distribution line; when only the bus section where the fault is located is determined, all distribution lines of the current bus section are obtained, and the zero-sequence current alarm information of the first intelligent device on different distribution lines is screened respectively, and the precise location of the ground fault is determined based on the zero-sequence current alarm information.

[0010] Furthermore, when the distribution line where the fault is located is determined, the precise location of the ground fault is determined by: querying the zero-sequence current alarm information uploaded by all smart devices in the current distribution line through the distribution line name and zero-sequence alarm keywords from the main station information, and determining whether the ground fault is located on the load side or the power supply side of the smart device.

[0011] Furthermore, when only the bus section where the fault is located is determined, the precise location of the ground fault is determined specifically as follows: based on the primary wiring diagram within the distribution automation master station, all distribution lines of the current bus section are screened out; the zero-sequence current alarm information of the first intelligent device in all distribution lines is screened from the master station information, and based on the obtained alarm information, it is determined whether the ground fault is located on the load side or the power supply side of the intelligent device.

[0012] Furthermore, when a ground fault occurs, the fault current flows from the fault point to the outgoing line interval of the substation. When the first main line equipment of the distribution line collects the fault current, it sends zero-sequence current alarm information to the distribution automation master station.

[0013] Furthermore, when there is no small current grounding line selection device and a grounding alarm signal of the backup protection bus of the substation is received, all distribution lines of the current bus section are screened out based on the primary wiring diagram in the distribution automation master station; the zero-sequence current alarm information of the first intelligent device in all distribution lines is screened from the master station information, and based on the alarm information obtained, it is determined whether the grounding fault is located on the load side or the power supply side of the intelligent device.

[0014] According to a second aspect of an embodiment of the present disclosure, a ground fault identification system based on multi-dimensional collaborative monitoring is provided, comprising:

[0015] A signal acquisition unit, which is used to acquire the uplink signal of the small current grounding line selection device in real time;

[0016] A rough position estimation unit, which is used to obtain a rough position of the ground fault based on the type of the uplink signal;

[0017] The precise position estimation unit is used to determine the precise position of the ground fault based on the zero-sequence current alarm information uploaded by all intelligent devices on the current distribution line when the distribution line where the fault is located is determined; when only the bus section where the fault is located is determined, all distribution lines of the current bus section are obtained, and the zero-sequence current alarm information of the first intelligent device on different distribution lines is screened respectively, and the precise position of the ground fault is determined based on the zero-sequence current alarm information.

[0018] According to a third aspect of an embodiment of the present disclosure, an electronic device is provided, comprising a memory, a processor, and a computer program stored and running on the memory, wherein when the processor executes the program, a ground fault identification method based on multi-dimensional collaborative monitoring is implemented.

[0019] According to a fourth aspect of an embodiment of the present disclosure, a non-transitory computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the method for determining a ground fault based on multi-dimensional collaborative monitoring is implemented.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] (1) The scheme disclosed in the present invention provides a method for identifying ground faults based on multi-dimensional collaborative monitoring. The scheme is based on the information uploaded by the small current grounding line selection device and combined with the information collected by the intelligent equipment of the distribution automation master station, so as to quickly and accurately identify the ground fault. At the same time, for the substation without a small current grounding line selection device, when the substation backup protection bus grounding alarm signal is received, all the distribution lines of the current bus section are screened out based on the primary wiring diagram in the distribution automation master station; the zero-sequence current alarm information of the first intelligent device in all the distribution lines is screened from the master station information, and the precise location of the ground fault is obtained based on the alarm information; the scheme has strong robustness and can adapt to various situations of the substation.

[0022] (2) The scheme disclosed in the present invention greatly reduces the time for fault finding and improves the reliability of power supply. In particular, it improves the personal safety factor of emergency repair personnel when faults occur in severe weather. It is suitable for information sharing of main distribution networks of various units. Since the systems are all internal systems, there is no information leakage involved and they can be widely promoted.

[0023] Advantages of additional aspects of the present disclosure will be given in part in the following description and in part will become apparent from the following description or will be learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings constituting a part of the present disclosure are used to provide a further understanding of the present disclosure. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure.

[0025] Figure 1 This is a flow chart of the ground fault identification method based on multi-dimensional collaborative monitoring described in the first embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] The present disclosure is further described below in conjunction with the accompanying drawings and embodiments.

[0027] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanation of the present disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present disclosure belongs.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] In the absence of conflict, the embodiments in the present disclosure and the features in the embodiments may be combined with each other.

[0030] Embodiment 1:

[0031] The purpose of this embodiment is to provide a ground fault identification method based on multi-dimensional collaborative monitoring.

[0032] A ground fault identification method based on multi-dimensional collaborative monitoring, comprising:

[0033] Obtain the uplink signal of the small current grounding line selection device in real time;

[0034] Based on the type of the sent signal, a rough position of the ground fault is obtained;

[0035] When the distribution line where the fault is located is determined, the precise location of the ground fault is determined based on the zero-sequence current alarm information uploaded by all intelligent devices on the current distribution line; when only the bus section where the fault is located is determined, all distribution lines of the current bus section are obtained, and the zero-sequence current alarm information of the first intelligent device on different distribution lines is screened respectively, and the precise location of the ground fault is determined based on the zero-sequence current alarm information.

[0036] Specifically, for ease of understanding, the solution disclosed in the present disclosure is described in detail below with reference to the accompanying drawings:

[0037] like Figure 1As shown, the scheme disclosed in the present invention is based on the deficiencies in the prior art, and uses the information uploaded by the small current grounding line selection device of the main grid IES700 system and the information collected by the intelligent equipment of the distribution automation master station to filter the information using an "AND" gate; the scheme disclosed in the present invention is described in conjunction with specific examples below:

[0038] 1. Data Acquisition

[0039] The data sources are all collected and uploaded by existing equipment, among which the small current grounding line selection device is an in-station equipment of the substation. Currently, 17 substations of Linshu Company have been installed with it. The distribution automation master station data is collected and uploaded by the intelligent equipment in operation of the line. Linshu Company has installed a total of 443 intelligent devices on its 125 public lines (including 152 intelligent section switches, 195 intelligent boundary switches, 55 intelligent ring network cabinets, and 41 fault indicators).

[0040] Among them, the small current grounding line selection device analyzes the zero-sequence current signal of the 10 kV line. It makes an internal judgment on the zero-sequence current collected by the line zero-sequence current transformer in the station. If the line selection is successful, it directly sends the grounding line signal. If the line selection is unsuccessful, it only sends the signal of the bus section where the grounding line is located.

[0041] The data collected by the intelligent equipment in operation on the line include the voltage, current, and zero-sequence current on the load side of the equipment. In this embodiment, only the zero-sequence current needs to be used, and the intelligent equipment sends the zero-sequence current value in real time. When the intelligent device collects a zero-sequence current value greater than the protection setting value, it is divided into two processing methods according to the protection setting value: one is to directly trip and isolate in the case of zero-sequence tripping; the other is to send the zero-sequence current alarm signal and the real-time zero-sequence current value to the distribution automation master station at the same time in the case of zero-sequence alarm. Since the scheme described in the present disclosure only uses a single zero-sequence current value, there is no need to pre-process the data, which improves the execution efficiency of the algorithm.

[0042] (II) Specific steps for ground fault identification

[0043] Step 1: receiving the signal sent by the small current grounding line selection device in the station or the grounding alarm signal of the backup protection of the substation;

[0044] Step 2: Process the received in-station signal and determine the location of the ground fault according to the signal (specifically substation-busbar section-distribution line, the precise level is determined by the small current grounding line selection device or busbar grounding alarm signal);

[0045] The step 2 specifically includes:

[0046] When the low current grounding line selection device successfully selects the line (that is, when the distribution line where the fault is located is determined), perform the following steps:

[0047] The algorithm searches the line name + zero-sequence alarm keyword from the master station information to filter out the zero-sequence current alarm information of all intelligent devices on the distribution line (the distribution automation master station contains a database processor and a history server, which store all real-time and historical information sent by the intelligent devices. The master station has an alarm information prompt function, but due to the large amount of information, the prompt information may scroll away from the current page due to data update), which is similar to the internal self-healing function of the master station to determine the fault interval (the master station system locates the fault according to the fault alarm information sent by the intelligent devices on the line. When the fault current flows through the intelligent device on the power supply side, the intelligent device collects a fault current greater than the protection setting value, which is sent to the master station through the wireless communication module. The internal logic of the master station determines that the fault point is on the load side of the intelligent device; if the intelligent device does not send fault information, the master station determines that the fault is on the power supply side of the intelligent device); determine the location of the grounding point, such as below a certain section switch or between a certain section switch 1 and a certain section switch 2, below a certain boundary switch, and below a certain ring network cabinet 3 interval, to guide the repair personnel to carry out precise repairs;

[0048] When the low current grounding line selection device does not select the line but only determines the busbar, the specific steps are as follows:

[0049] First, call the primary wiring diagram in the distribution automation master station to screen all the distribution lines of the bus section, and use the master station to screen all the first intelligent devices of the distribution lines (according to the current flow from the 10 kV interval of the substation to the end of the line is positive, the first one refers to the first main line intelligent device below the outlet point, and the master station's own logic can determine the first intelligent device through the 10 kV primary single-line diagram) zero-sequence current alarm information. After the ground fault occurs, the fault current flows from the fault point to the substation outlet interval. The first main line intelligent device of the line can collect the fault current and determine the grounding line. The subsequent process is the same as the previous one;

[0050] Furthermore, when individual substations have not been modified to install small current grounding line selection devices and receive the substation backup protection grounding alarm signal, all distribution lines of the current bus section are screened out based on the primary wiring diagram in the distribution automation master station; the zero-sequence current alarm information of the first intelligent device in all distribution lines is screened from the master station information, and based on the alarm information obtained, it is determined whether the grounding fault is located on the load side or the power supply side of the intelligent device.

[0051] Furthermore, the scheme disclosed in this disclosure requires the deployment of small current grounding line selection devices (first, the substations that have installed the device are operated and maintained daily by substation professionals to ensure the stable operation of the device; second, the substations that have not installed the device need to use the technical transformation and overhaul project funds in combination with the spring and autumn inspection and power outage plan. The two substations that have not been installed by Linshu Company have project support and need to cooperate with the implementation of the power outage plan) and the promotion of the installation and monitoring scope of distribution automation intelligent equipment (according to the standardized configuration requirements of the distribution line, the technical transformation and overhaul project funds are combined with the spring and autumn inspection and power outage plan to continue to increase line intelligent equipment), which will be gradually realized with the improvement of the practical application of distribution automation. Ultimately, the coordinated and accurate identification of the fault range is achieved when a single-phase grounding fault occurs.

[0052] The ground fault identification method based on the multi-dimensional collaborative monitoring disclosed in the present invention greatly reduces the fault finding time and improves the power supply reliability, especially when faults occur in severe weather, which improves the personal safety factor of emergency repair personnel. It is suitable for the main distribution network information sharing of various units. Since the systems are all internal systems, there is no information leakage involved and can be vigorously promoted.

[0053] Embodiment 2:

[0054] The purpose of this embodiment is to provide a ground fault identification system based on multi-dimensional collaborative monitoring.

[0055] A ground fault identification system based on multi-dimensional collaborative monitoring, comprising:

[0056] A signal acquisition unit, which is used to acquire the uplink signal of the small current grounding line selection device in real time;

[0057] A rough position estimation unit, which is used to obtain a rough position of the ground fault based on the type of the uplink signal;

[0058] The precise position estimation unit is used to determine the precise position of the ground fault based on the zero-sequence current alarm information uploaded by all intelligent devices on the current distribution line when the distribution line where the fault is located is determined; when only the bus section where the fault is located is determined, all distribution lines of the current bus section are obtained, and the zero-sequence current alarm information of the first intelligent device on different distribution lines is screened respectively, and the precise position of the ground fault is determined based on the zero-sequence current alarm information.

[0059] In further embodiments, there is also provided:

[0060] An electronic device includes a memory and a processor, and computer instructions stored in the memory and executed on the processor, wherein when the computer instructions are executed by the processor, the method described in Embodiment 1 is performed. For the sake of brevity, no further description is given here.

[0061] It should be understood that in this embodiment, the processor 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, off-the-shelf 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.

[0062] The memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0063] A computer-readable storage medium is used to store computer instructions. When the computer instructions are executed by a processor, the method described in embodiment 1 is completed.

[0064] The method in the first embodiment can be directly embodied as a hardware processor, or a combination of hardware and software modules in the processor. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware. To avoid repetition, it will not be described in detail here.

[0065] Those skilled in the art will appreciate that the units, i.e., algorithm steps, of the various examples described in conjunction with this embodiment can be implemented in electronic hardware or in 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 this application.

[0066] The above-mentioned embodiment provides a ground fault identification method and system based on multi-dimensional collaborative monitoring, which can be implemented and has broad application prospects.

[0067] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A ground fault identification method based on multi-dimensional collaborative monitoring, characterized in that: include: Obtain the uplink signal of the small current grounding line selection device in real time; Based on the type of the sent signal, a rough position of the ground fault is obtained; When the distribution line where the fault is located is determined, the precise location of the ground fault is determined based on the zero-sequence current alarm information uploaded by all smart devices on the current distribution line. Specifically, the zero-sequence current alarm information uploaded by all smart devices in the current distribution line is queried from the master station information by using the distribution line name and zero-sequence alarm keyword to determine whether the ground fault is located on the load side or the power supply side of the smart device. The master station system locates the fault according to the fault alarm information sent by the intelligent device in operation. When the fault current flows through the intelligent device on the power supply side, the intelligent device collects a fault current greater than the protection setting value and sends it to the master station through the wireless communication module. The internal logic of the master station determines that the fault point is on the load side of the intelligent device. If the intelligent device does not send fault information, the master station determines that the fault is on the power supply side of the intelligent device. When only the bus section where the fault is located is determined, the precise location of the ground fault is determined, specifically: all distribution lines of the current bus section are obtained, the zero-sequence current alarm information of the first intelligent device on different distribution lines is screened respectively, and the precise location of the ground fault is determined based on the zero-sequence current alarm information; based on the primary wiring diagram in the distribution automation master station, all distribution lines of the current bus section are screened; Filter the zero-sequence current alarm information of the first intelligent device in all distribution lines from the master station information, and determine whether the ground fault is located on the load side or the power side of the intelligent device according to the obtained alarm information; When there is no low-current grounding line selection device and the substation backup protection grounding alarm signal is received, all distribution lines of the current bus section are screened out based on the primary wiring diagram in the distribution automation master station; Filter the zero-sequence current alarm information of the first intelligent device in all distribution lines from the master station information, and determine whether the ground fault is located on the load side or the power side of the intelligent device according to the obtained alarm information; The first intelligent device is specifically the first main line intelligent device below the outgoing line point, based on the current flow direction from the 10kV interval of the substation to the end of the line as the positive direction.

2. A ground fault identification method based on multi-dimensional collaborative monitoring as claimed in claim 1, characterized in that: When a ground fault occurs, the fault current flows from the fault point to the outgoing line interval of the substation. When the first main line equipment of the distribution line collects the fault current, it sends zero-sequence current alarm information to the distribution automation master station.

3. A ground fault identification method based on multi-dimensional collaborative monitoring as claimed in claim 1, characterized in that: The rough location of the ground fault is obtained based on the type of the upward signal, specifically: if the type of the upward signal is a ground line signal, the distribution line where the ground fault is located is obtained; if the type of the upward signal is a bus section signal where the ground line is located, the bus section where the ground fault is located is obtained.

4. A ground fault identification system based on multi-dimensional collaborative monitoring, using a ground fault identification method based on multi-dimensional collaborative monitoring as claimed in claim 1, characterized in that: include: A signal acquisition unit, which is used to acquire the uplink signal of the small current grounding line selection device in real time; A rough position estimation unit, which is used to obtain a rough position of the ground fault based on the type of the uplink signal; The precise location estimation unit is used to determine the precise location of the ground fault based on the zero-sequence current alarm information uploaded by all smart devices on the current distribution line when the distribution line where the fault is located is determined. Specifically, the zero-sequence current alarm information uploaded by all smart devices in the current distribution line is queried from the master station information by the distribution line name and zero-sequence alarm keyword to determine whether the ground fault is located on the load side or the power supply side of the smart device. The master station system locates the fault according to the fault alarm information sent by the intelligent device in operation. When the fault current flows through the intelligent device on the power supply side, the intelligent device collects a fault current greater than the protection setting value and sends it to the master station through the wireless communication module. The internal logic of the master station determines that the fault point is on the load side of the intelligent device. If the intelligent device does not send fault information, the master station determines that the fault is on the power supply side of the intelligent device. When only the bus section where the fault is located is determined, the precise location of the ground fault is determined, specifically: all distribution lines of the current bus section are obtained, the zero-sequence current alarm information of the first intelligent device on different distribution lines is screened respectively, and the precise location of the ground fault is determined based on the zero-sequence current alarm information; based on the primary wiring diagram in the distribution automation master station, all distribution lines of the current bus section are screened; Filter the zero-sequence current alarm information of the first intelligent device in all distribution lines from the master station information, and determine whether the ground fault is located on the load side or the power side of the intelligent device according to the obtained alarm information; When there is no low-current grounding line selection device and the substation backup protection grounding alarm signal is received, all distribution lines of the current bus section are screened out based on the primary wiring diagram in the distribution automation master station; Filter the zero-sequence current alarm information of the first intelligent device in all distribution lines from the master station information, and determine whether the ground fault is located on the load side or the power side of the intelligent device according to the obtained alarm information; The first intelligent device is specifically the first main line intelligent device below the outgoing line point, based on the current flow direction from the 10kV interval of the substation to the end of the line as the positive direction.

5. An electronic device comprising a memory, a processor and a computer program stored and running on the memory, characterized in that: When the processor executes the program, it implements a ground fault identification method based on multi-dimensional collaborative monitoring as described in any one of claims 1 to 3.

6. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, a ground fault identification method based on multi-dimensional collaborative monitoring as described in any one of claims 1 to 3 is implemented.

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