CN116224148A - Single-phase grounding fault analysis and treatment method and system for small-current grounding system - Google Patents

Single-phase grounding fault analysis and treatment method and system for small-current grounding system Download PDF

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Publication number
CN116224148A
CN116224148A CN202211640709.9A CN202211640709A CN116224148A CN 116224148 A CN116224148 A CN 116224148A CN 202211640709 A CN202211640709 A CN 202211640709A CN 116224148 A CN116224148 A CN 116224148A
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fault
voltage
phase
current
bus
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Inventor
张海
张在杰
王继文
公冶祥广
刘宗杰
朱海鹏
刘晓龙
陶旋旋
魏春雪
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Jining Power Supply Co
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Jining Power Supply Co
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/08—Limitation or suppression of earth fault currents, e.g. Petersen coil
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/52—Testing for short-circuits, leakage current or ground faults
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
    • Y04S10/52—Outage or fault management, e.g. fault detection or location

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
  • Locating Faults (AREA)

Abstract

The invention provides a single-phase earth fault analysis and treatment method and a system for a small-current grounding system, which relate to the technical field of power grid fault judgment and comprise the steps of collecting three-phase voltage and zero-sequence voltage of a bus of the small-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time; when the ground fault occurs, the resistor switching device is controlled to switch into the load resistor, the frequency of switching into and off the load resistor is controlled, and a current waveform signal generated by the switching resistor is obtained; analyzing the current waveform to judge whether single-phase grounding faults occur or not; after a fault occurs, a fault line and a fault phase are selected, the amplitude and the vector of the voltage to be injected are calculated and sent to a flexible voltage source, zero sequence voltage is injected at a neutral point through the flexible voltage source, and when the zero sequence voltage exceeds a starting fixed value, the distance from the fault point to a bus is calculated, so that accurate positioning and repairing are performed; the fault point is accurately positioned, and the fault processing speed is improved.

Description

Single-phase grounding fault analysis and treatment method and system for small-current grounding system
Technical Field
The disclosure relates to the technical field of power grid fault judgment, in particular to a single-phase grounding fault analysis and treatment method and system of a small-current grounding system.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
In low current grounding systems, single phase grounding is a more common type of fault. When the small current grounding system is grounded unidirectionally, the fault relative ground voltage is reduced, the non-fault relative ground voltage is increased, the line voltage is still symmetrical, in this state, the grounding current is very small, and the operation can be allowed for 1-2 hours in order to ensure the power supply reliability, but the breakdown of the weak insulation part, the saturation of the iron core of the voltage transformer and the overvoltage of the system are easily caused due to the non-fault arc light overvoltage, and the problems of cable burning caused by the fault arc light, personal electric shock casualties are easily caused. Therefore, whether single-phase earth faults occur or not and the distance from the fault point to the bus are judged, the fault point is quickly found, and power supply is carried out, so that the power failure time is reduced.
For a small-current grounding system, the steady-state fault characteristics of some single-phase grounding rear-steady-state fault are not obvious, and the conventional algorithm cannot be selected. The characteristic frequency of the transient current is uncertain when the ground fault occurs, the duration is very short, the transient current is only 10-20 mA when the ground fault is high, the algorithm capable of accurately obtaining the transient characteristic quantity is difficult to realize to a certain extent, the transient algorithm is used, high sampling rate and sensitivity are required, because the algorithm and hardware requirements of the transient method line selection pair are very high, the line selection accuracy of most of the current line selection devices is very low, if the ground fault of a distribution line cannot be cut off for a long time, after the distribution line falls to the ground, the distribution line is easy to self-extinguish due to step voltage or contact voltage, the distribution line is easy to burn, fire is caused, and the power supply reliability is seriously affected. The ground fault detection of some fault indicators is usually to measure the current mutation and duration in the line by an electromagnetic induction method to judge the fault, or to quantify the single judgment fault by harmonic mutation, and the single detection is unreliable, and frequently malfunction or refusal.
Disclosure of Invention
In order to solve the problems, the disclosure provides a method and a system for analyzing and disposing single-phase grounding faults of a low-current grounding system, which are used for judging the single-phase grounding faults of the low-current grounding system and then positioning the faults so as to improve the accuracy of judging the grounding faults.
According to some embodiments, the present disclosure employs the following technical solutions:
a method for analyzing and disposing single-phase earth faults of a small-current grounding system, comprising:
collecting three-phase voltage and zero-sequence voltage of a bus of a low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
when the ground fault occurs, the resistor switching device is controlled to switch into the load resistor, the frequency of switching into and off the load resistor is controlled, and a current waveform signal generated by the switching resistor is obtained;
analyzing the current waveform to judge whether single-phase grounding faults occur or not;
after the fault occurs, a fault line and a fault phase are selected, the amplitude and the vector of the voltage to be injected are calculated and sent to a flexible voltage source, zero sequence voltage is injected into a neutral point through the flexible voltage source, and when the zero sequence voltage exceeds a starting fixed value, the distance from the fault point to a bus is calculated, so that accurate positioning and repairing are performed.
According to some embodiments, the present disclosure employs the following technical solutions:
a low current grounding system single phase earth fault analysis and handling system comprising:
the data sampling module is used for collecting three-phase voltage and zero-sequence voltage of a bus of the low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
the signal separation module is used for controlling the resistor switching device to switch into the load resistor after the ground fault occurs, controlling the frequency of switching into and switching off the load resistor, and obtaining a current waveform signal generated by the switching resistor;
the fault judging module is used for analyzing the current waveform and judging whether a single-phase grounding fault occurs or not;
and the accurate positioning module is used for selecting a fault line and a fault phase after a fault occurs, calculating the amplitude value and the vector of the voltage to be injected, sending the voltage to the flexible voltage source, injecting zero sequence voltage into a neutral point through the flexible voltage source, and calculating the distance from the fault point to a bus when the zero sequence voltage exceeds a starting fixed value so as to perform accurate positioning repair.
According to some embodiments, the present disclosure employs the following technical solutions:
a non-transitory computer readable storage medium for storing computer instructions which, when executed by a processor, implement the method of single-phase ground fault analysis and handling of a low-current grounding system.
According to some embodiments, the present disclosure employs the following technical solutions:
an electronic device, comprising: a processor, a memory, and a computer program; the processor is connected with the memory, the computer program is stored in the memory, and when the electronic equipment runs, the processor executes the computer program stored in the memory so as to enable the electronic equipment to execute the single-phase grounding fault analysis and treatment method for the small-current grounding system.
Compared with the prior art, the beneficial effects of the present disclosure are:
the method disclosed by the invention improves the accuracy of judging the line ground fault, shortens the fault inquiry time, reduces the daily maintenance workload of the distribution network line, improves the working efficiency and ensures the reliable operation of the distribution network system.
The method can measure the line voltage of the bus and the line end, can accurately locate the fault point, and improves the fault processing speed.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate and explain the exemplary embodiments of the disclosure and together with the description serve to explain the disclosure, and do not constitute an undue limitation on the disclosure.
FIG. 1 is a diagram of a system connection architecture in an embodiment of the present disclosure;
FIG. 2 is a three-phase voltage phase diagram in an embodiment of the present disclosure; wherein (a) in fig. 2 is a three-phase voltage phase diagram during normal operation; fig. 2 (b) shows the voltage phase when phase a is grounded; fig. 2 (c) is a voltage phase diagram after flexible voltage injection.
The specific embodiment is as follows:
the disclosure is further described below with reference to the drawings and examples.
It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments in accordance with the present disclosure. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
Example 1
In one embodiment of the present disclosure, a method for analyzing and disposing a single-phase ground fault of a low-current grounding system is provided, including:
s1: collecting three-phase voltage and zero-sequence voltage of a bus of a low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
s2: when the ground fault occurs, the resistor switching device is controlled to switch into the load resistor, the frequency of switching into and off the load resistor is controlled, and a current waveform signal generated by the switching resistor is obtained;
s3: analyzing the current waveform to judge whether single-phase grounding faults occur or not;
s4: after the fault occurs, a fault line and a fault phase are selected, the amplitude and the vector of the voltage to be injected are calculated and sent to a flexible voltage source, zero sequence voltage is injected into a neutral point through the flexible voltage source, and when the zero sequence voltage exceeds a starting fixed value, the distance from the fault point to a bus is calculated, so that accurate positioning and repairing are performed.
As an embodiment, specifically, when a single-phase grounding fault occurs, a protection device of a transformer substation in a small-current grounding system controls a resistor switching device to switch into a load resistor, and controls the frequency of switching into and off the load resistor, so as to obtain a current waveform signal generated by the switching resistor, wherein the current waveform signal is called a switching resistor signal source;
carrying out positive and negative half-wave separation on an alternating current fundamental wave in a line with the ground fault in a power distribution system;
carrying out positive and negative half-wave separation on fifth harmonic waves in a line with the ground fault in a power distribution system;
the first half wave of the positive half wave and the negative half wave of the fundamental wave are respectively and correspondingly compared with the first half wave of the positive half wave and the negative half wave of the fifth harmonic; when the first half wave of the positive half wave and the negative half wave of the fundamental wave are in phase with the first half wave of the positive half wave and the negative half wave of the fifth harmonic respectively, and the waveform of the fundamental wave is consistent with the waveform of the current generated by the switching resistor, single-phase grounding faults are judged to occur.
After the ground fault occurs, a fault line and a fault phase are selected, the amplitude value and the vector of the voltage to be injected are calculated and sent to a flexible voltage source, zero sequence voltage is injected at a neutral point through the flexible voltage source, the voltage of the fault point is controlled to be 0, namely, the fault point is in arc extinction so that the fault current is 0, and the safe operation without the ground fault stop is realized.
The working principle is as follows: when the phase A is grounded, the voltage phase is as shown in (b) of FIG. 2, and the ground potential N is from 0 to E along the broken line as the ground resistance becomes smaller A Offset, flexible voltage source injection one and E A After the voltage vectors with equal magnitude and opposite phases, the phase A of the fault phase is relative to the ground voltage as U A ＝E A -E A =0. The A-phase voltage is 0, the earth current is 0, and the B-phase voltage is U B ＝E B -E A ＝E BA The C-phase voltage to ground is U C ＝E C -E A ＝E CA The non-faulty phase-to-ground voltage becomes the line voltage.
As an embodiment, the process of calculating the distance from the fault point to the bus bar includes: the line impedance and the load current enable a voltage difference to exist between the bus and the line end, the voltage difference is in direct proportion to the length of the line, after single-phase grounding faults occur, the voltage difference bus from the fault point of the fault line to the bus and the voltage difference end from the fault point to the line end are also in direct proportion to the distance, after arc extinction is completed, when the voltage of the fault point to the ground is 0, the fault phase voltage at the bus and the fault phase voltage at the line end are collected, and the distance from the fault point to the bus is calculated.
The distance formula for calculating the fault point to the bus is as follows:
Figure BDA0004008880610000061
wherein L is the distance from the fault point to the bus, U fault_bus U is the fault phase voltage at the bus fault_end For line-end fault phase voltage, L total Is the total length of the line.
When the zero sequence voltage exceeds the starting fixed value, the ground fault is judged to occur, and a fault phase is judged according to the three-phase voltage; at the moment, the controller sends a complete arc extinction instruction to the flexible arc extinction module, a voltage is injected into the flexible arc extinction module to achieve complete arc extinction of a fault point, the fault phase voltage at the bus and the fault phase voltage at the end of the line are collected after complete arc extinction, and the distance from the fault point to the bus is calculated according to the calculation formula.
Example 2
In one embodiment of the present disclosure, there is provided a low current grounding system single phase earth fault analysis and handling system, comprising:
the data sampling module is used for collecting three-phase voltage and zero-sequence voltage of a bus of the low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
the signal separation module is used for controlling the resistor switching device to switch into the load resistor after the ground fault occurs, controlling the frequency of switching into and switching off the load resistor, and obtaining a current waveform signal generated by the switching resistor;
the fault judging module is used for analyzing the current waveform and judging whether a single-phase grounding fault occurs or not;
and the accurate positioning module is used for selecting a fault line and a fault phase after a fault occurs, calculating the amplitude value and the vector of the voltage to be injected, sending the voltage to the flexible voltage source, injecting zero sequence voltage into a neutral point through the flexible voltage source, and calculating the distance from the fault point to a bus when the zero sequence voltage exceeds a starting fixed value so as to perform accurate positioning repair.
The data sampling module comprises a sampling unit, the signal separation module comprises a signal separation unit, the fault judgment module comprises a CPU signal processing unit, the CPU signal processing unit is connected with a fault execution unit, and the sampling unit, the signal separation unit, the CPU signal processing unit and the fault indication execution unit are sequentially arranged
The sampling unit is connected with the sampling unit, the sampling unit collects the current quantity of the single-phase grounding fault line and the current quantity generated by the switching resistor, the signal separation unit is used for separating the positive half wave and the negative half wave of the fundamental wave and the fifth harmonic wave of the current of the single-phase grounding fault line, the CPU signal processing unit is used for comparing and analyzing the first half wave of the positive half wave and the negative half wave of the fundamental wave and the first half wave of the fifth harmonic wave and the first half wave of the negative half wave, meanwhile, the current waveform generated by the fundamental wave waveform and the switching resistor is compared for fault judgment, and finally the fault signal is output and fault indication is sent out through the fault execution unit. The fault execution unit further comprises an alternating current electric field strength sensor for acquiring the strength of the fault grounding alternating current electric field, and the alternating current electric field strength sensor is connected with the CPU signal processing unit. The alternating current electric field strength sensor is installed in a non-contact manner and is not directly connected with load equipment. When a ground fault occurs, the ac electric field strength sensor will detect a change in the electric field in the line and a drop in voltage.
The accurate positioning module comprises an arc extinction device which is connected with a flexible voltage source, a step-up transformer and a single-phase switch, as shown in fig. 1, wherein (Z) is a grounding transformer;
the system performs the method steps described in embodiment 1, including:
collecting three-phase voltage and zero-sequence voltage of a bus of a low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
when the ground fault occurs, the resistor switching device is controlled to switch into the load resistor, the frequency of switching into and off the load resistor is controlled, and a current waveform signal generated by the switching resistor is obtained;
analyzing the current waveform to judge whether single-phase grounding faults occur or not;
after the fault occurs, a fault line and a fault phase are selected, the amplitude and the vector of the voltage to be injected are calculated and sent to a flexible voltage source, zero sequence voltage is injected into a neutral point through the flexible voltage source, and when the zero sequence voltage exceeds a starting fixed value, the distance from the fault point to a bus is calculated, so that accurate positioning and repairing are performed.
Example 3
In one embodiment of the present disclosure, a non-transitory computer readable storage medium is provided for storing computer instructions that, when executed by a processor, implement the steps of a low current grounding system single-phase ground fault analysis and handling method.
Example 4
In one embodiment of the present disclosure, there is provided an electronic device including: a processor, a memory, and a computer program; the processor is connected with the memory, the computer program is stored in the memory, and when the electronic equipment runs, the processor executes the computer program stored in the memory so as to enable the electronic equipment to execute the steps of the single-phase grounding fault analysis and treatment method for the small-current grounding system.
The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While the specific embodiments of the present disclosure have been described above with reference to the drawings, it should be understood that the present disclosure is not limited to the embodiments, and that various modifications and changes can be made by one skilled in the art without inventive effort on the basis of the technical solutions of the present disclosure while remaining within the scope of the present disclosure.

Claims (10)

1. A method for analyzing and disposing single-phase earth faults of a small-current grounding system, which is characterized by comprising the following steps:
collecting three-phase voltage and zero-sequence voltage of a bus of a low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
when the ground fault occurs, the resistor switching device is controlled to switch into the load resistor, the frequency of switching into and off the load resistor is controlled, and a current waveform signal generated by the switching resistor is obtained;
analyzing the current waveform to judge whether single-phase grounding faults occur or not;
after the fault occurs, a fault line and a fault phase are selected, the amplitude and the vector of the voltage to be injected are calculated and sent to a flexible voltage source, zero sequence voltage is injected into a neutral point through the flexible voltage source, and when the zero sequence voltage exceeds a starting fixed value, the distance from the fault point to a bus is calculated, so that accurate positioning and repairing are performed.
2. The method for analyzing and disposing single-phase ground faults of a small current grounding system according to claim 1, wherein the process of analyzing current waveforms is as follows: and carrying out positive and negative half-wave separation on an alternating current fundamental wave in the current waveform of the grounding fault line, and carrying out positive and negative half-wave separation on fifth harmonic waves in the grounding fault line.
3. The method for analyzing and disposing single-phase grounding faults of a low-current grounding system according to claim 2, wherein first half waves of positive and negative half waves of a fundamental wave are respectively compared with first half waves of positive and negative half waves of fifth harmonic waves, and when the first half waves of the positive and negative half waves of the fundamental wave are respectively in phase with the first half waves of the positive and negative half waves of the fifth harmonic waves, and the waveform of the fundamental wave is consistent with the waveform of current generated by a switching resistor, single-phase grounding faults are judged to occur.
4. The method for analyzing and disposing single-phase grounding faults of a small-current grounding system according to claim 1 is characterized in that when zero sequence voltage exceeds a starting fixed value, grounding faults are judged to occur, fault phases are judged according to three-phase voltage, arc extinction instructions are sent out, a voltage is injected to achieve complete elimination of fox at fault points, fault phase voltage at the bus and line end fault phase voltage at the moment are collected after complete arc extinction, and the distance from the fault points to the bus is calculated.
5. The method for analyzing and disposing single-phase grounding faults of a small-current grounding system according to claim 4, wherein the process of calculating the distance from a fault point to a bus comprises the steps of: the line impedance and the load current enable a voltage difference to exist between the bus and the line end, the voltage difference is in direct proportion to the length of the line, after single-phase grounding faults occur, the voltage difference bus from the fault point of the fault line to the bus and the voltage difference end from the fault point to the line end are also in direct proportion to the distance, after arc extinction is completed, when the voltage of the fault point to the ground is 0, the fault phase voltage at the bus and the fault phase voltage at the line end are collected, and the distance from the fault point to the bus is calculated.
6. The method for analyzing and disposing single-phase grounding faults of a small-current grounding system according to claim 4, wherein a distance formula from a calculated fault point to a bus is as follows:
Figure FDA0004008880600000021
wherein L is the distance from the fault point to the bus, U fault_bus U is the fault phase voltage at the bus fault_end For line-end fault phase voltage, L total Is the total length of the line.
7. A method of analyzing and disposing a single-phase ground fault of a low-current grounding system according to claim 1, wherein said current waveform signal is referred to as a switched resistance signal source.
8. A small current grounding system single phase earth fault analysis and handling system, comprising:
the data sampling module is used for collecting three-phase voltage and zero-sequence voltage of a bus of the low-current grounding system, zero-sequence current of the head end of each branch, and three-phase voltage and zero-sequence voltage of the tail end of each branch in real time;
the signal separation module is used for controlling the resistor switching device to switch into the load resistor after the ground fault occurs, controlling the frequency of switching into and switching off the load resistor, and obtaining a current waveform signal generated by the switching resistor;
the fault judging module is used for analyzing the current waveform and judging whether a single-phase grounding fault occurs or not;
and the accurate positioning module is used for selecting a fault line and a fault phase after a fault occurs, calculating the amplitude value and the vector of the voltage to be injected, sending the voltage to the flexible voltage source, injecting zero sequence voltage into a neutral point through the flexible voltage source, and calculating the distance from the fault point to a bus when the zero sequence voltage exceeds a starting fixed value so as to perform accurate positioning repair.
9. A non-transitory computer readable storage medium storing computer instructions which, when executed by a processor, implement a small current grounding system single phase earth fault analysis and handling method according to any of claims 1-7.
10. An electronic device, comprising: a processor, a memory, and a computer program; wherein the processor is connected to the memory and the computer program is stored in the memory, said processor executing said computer program stored in the memory when the electronic device is running, to cause the electronic device to perform a method for implementing a single phase earth fault analysis and handling of a low current earth system according to any of claims 1-7.
CN202211640709.9A 2022-12-20 2022-12-20 Single-phase grounding fault analysis and treatment method and system for small-current grounding system Pending CN116224148A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117269700A (en) * 2023-11-20 2023-12-22 国网江西省电力有限公司电力科学研究院 Voltage transformer insulation defect diagnosis method based on fault wave recording information

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117269700A (en) * 2023-11-20 2023-12-22 国网江西省电力有限公司电力科学研究院 Voltage transformer insulation defect diagnosis method based on fault wave recording information
CN117269700B (en) * 2023-11-20 2024-03-12 国网江西省电力有限公司电力科学研究院 Voltage transformer insulation defect diagnosis method based on fault wave recording information

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