CN115166585B - Ground fault detection anti-misjudgment method and device and electronic equipment - Google Patents
Ground fault detection anti-misjudgment method and device and electronic equipment Download PDFInfo
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- CN115166585B CN115166585B CN202211092152.XA CN202211092152A CN115166585B CN 115166585 B CN115166585 B CN 115166585B CN 202211092152 A CN202211092152 A CN 202211092152A CN 115166585 B CN115166585 B CN 115166585B
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- 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
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- 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
- G01R31/58—Testing of lines, cables or conductors
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- 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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Abstract
The invention provides a method and a device for preventing ground fault detection from misjudgment and electronic equipment. The method comprises the following steps: acquiring power data of a line where a target circuit breaker is located in a power system in real time; when the first sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection duration, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a first preset detection condition; the first preset detection condition is that the number of phase voltage zero-crossing points of a period which is located before the zero-sequence voltage abrupt change point and is closest to the abrupt change is not equal to two, or the effective value of the phase voltage of a period which is located before the abrupt change and is closest to the abrupt change is smaller than a preset voltage threshold value. The invention can solve the problem that the normal closing of the breaker is wrongly judged as the ground fault.
Description
Technical Field
The invention relates to the technical field of power monitoring, in particular to a ground fault detection anti-misjudgment method and device and electronic equipment.
Background
The neutral point of the power system usually adopts an operation mode of being not grounded or being grounded through an arc suppression coil. The single-phase earth fault is the most common fault in the power system, because the environment of the overhead transmission line is severe, and in the actual operation process of the power distribution system, factors such as lightning stroke, strong wind, branches and mountain fire can cause the single-phase earth fault of the line.
At present, whether a ground fault occurs in a power system is generally determined by detecting whether a zero sequence voltage-zero sequence current occurs, and if the ground fault occurs, the fault can be removed by controlling a circuit breaker to trip. However, in this way, the ground fault is determined by detecting whether the zero sequence voltage-zero sequence current occurs, so that the problem of ground fault misdetermination is easily caused.
Disclosure of Invention
The embodiment of the invention provides a method and a device for detecting a ground fault and preventing misjudgment and electronic equipment, and aims to solve the problem of misjudgment of the ground fault in the prior art.
In a first aspect, an embodiment of the present invention provides a method for preventing a ground fault from being misjudged, including:
acquiring power data of a line where a target circuit breaker is located in a power system in real time;
when the first sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection duration, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a first preset detection condition; the first preset detection condition is that the number of zero-crossing points of the phase voltage of one period which is located before and nearest to the sudden change is not equal to two, or the effective value of the phase voltage of one period which is located before and nearest to the sudden change is smaller than a preset voltage threshold value.
In one possible implementation, the power data includes phase voltage data; the first preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before and closest to the mutation is not equal to two;
according to the electric power data and the first preset detection condition, generating a ground fault detection result of a line where the target circuit breaker is located, wherein the ground fault detection result comprises the following steps:
acquiring the zero crossing number of phase voltage in a period which is before the first mutation and is closest to the first mutation;
and if the zero crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data includes phase voltage data; the first preset detection condition is that the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value;
according to the electric power data and the first preset detection condition, generating a ground fault detection result of a line where the target circuit breaker is located, wherein the ground fault detection result comprises the following steps:
acquiring a phase voltage effective value of a period which is before and closest to the first mutation of the phase voltage;
and if the phase voltage effective value is smaller than the preset voltage threshold value, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In a possible implementation manner, after generating a ground fault detection result of a line on which a target circuit breaker is located, the ground fault detection false-judgment preventing method further includes:
when the second mutation of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection time, acquiring the time difference between the second mutation time and the first mutation time;
and if the time difference is smaller than the preset time threshold, not performing ground fault detection on the second sudden change, otherwise, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a second preset detection condition.
In one possible implementation, the power data includes phase voltage data; the second preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before the sudden change and is closest to the sudden change is not equal to two;
generating a ground fault detection result of a line where the target circuit breaker is located according to the power data and a second preset detection condition, wherein the ground fault detection result comprises the following steps:
acquiring the number of phase voltage zero-crossing points of a phase voltage in a period which is before the second sudden change and is closest to the second sudden change;
and if the zero-crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data includes phase voltage data; the second preset detection condition is that the effective value of the phase voltage of a period which is before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value, and the number of zero-crossing points of the phase voltage of a period which is before the sudden change and is closest to the sudden change is not equal to two;
generating a ground fault detection result of a line where the target circuit breaker is located according to the power data and a second preset detection condition, wherein the ground fault detection result comprises the following steps:
acquiring a phase voltage effective value of a phase voltage in a period which is before the second sudden change and is closest to the second sudden change, and acquiring a phase voltage zero-crossing point number of the phase voltage in a period which is before the second sudden change and is closest to the second sudden change;
and if the phase voltage effective value is smaller than the preset voltage threshold value and the phase voltage zero-crossing number is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In a second aspect, an embodiment of the present invention provides a ground fault detection false-judgment prevention device, including:
the acquisition module is used for acquiring the power data of a line where a target circuit breaker is located in the power system in real time;
the detection module is used for generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a first preset detection condition when the first sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection time; the first preset detection condition is that the number of zero-crossing points of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is not equal to two, or the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value.
In one possible implementation, the power data includes phase voltage data; the first preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before and closest to the mutation is not equal to two;
the detection module is further configured to:
acquiring the number of phase voltage zero-crossing points of a phase voltage in a period which is before the first mutation and is closest to the first mutation; and if the zero crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data includes phase voltage data; the first preset detection condition is that the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value;
the detection module is further configured to:
acquiring a phase voltage effective value of a period which is before and closest to the first mutation of the phase voltage; and if the phase voltage effective value is smaller than the preset voltage threshold value, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation manner, the detection module is further configured to:
when the second mutation of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection time, acquiring the time difference between the second mutation time and the first mutation time;
and if the time difference is smaller than the preset time threshold, not performing ground fault detection on the second sudden change, otherwise, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a second preset detection condition.
In one possible implementation, the power data includes phase voltage data; the second preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before the sudden change and is closest to the sudden change is not equal to two;
the detection module is further configured to:
acquiring the number of phase voltage zero-crossing points of a phase voltage in a period which is before the second sudden change and is closest to the second sudden change;
and if the zero-crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data includes phase voltage data; the second preset detection condition is that the effective value of the phase voltage of a period which is before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value, and the number of zero-crossing points of the phase voltage of a period which is before the sudden change and is closest to the sudden change is not equal to two;
the detection module is further configured to:
acquiring a phase voltage effective value of a phase voltage in a period which is positioned before the second time mutation and is closest to the second time mutation, and acquiring a phase voltage zero-crossing point number of the phase voltage in a period which is positioned before the second time mutation and is closest to the second time mutation;
and if the phase voltage effective value is smaller than the preset voltage threshold value and the phase voltage zero-crossing point number is not equal to two, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In a third aspect, an embodiment of the present invention provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements the steps of the method according to the first aspect or any possible implementation manner of the first aspect when executing the computer program.
The embodiment of the invention provides a method, a device and electronic equipment for preventing misjudgment of ground fault detection, which can judge whether the sudden change is caused by ground fault or circuit breaker closing through a preset detection condition when the zero-sequence voltage sudden change is detected, so that the problem that the normal circuit breaker closing is misjudged as the ground fault is solved, the false tripping of a circuit breaker is avoided, and the ground fault detection accuracy is higher.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a flowchart illustrating an implementation of a method for detecting a ground fault and preventing misjudgment according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a ground fault waveform provided by an embodiment of the present invention;
fig. 3 is a schematic waveform diagram of closing of a circuit breaker according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of phase voltage zero crossings provided by an embodiment of the present invention;
fig. 5 is a flowchart illustrating an implementation of another method for detecting a ground fault and preventing an erroneous determination according to an embodiment of the present invention;
fig. 6 is a schematic view of an application scenario in which the circuit breakers FTU1 to FTU6 are all in a closing state according to an embodiment of the present invention;
fig. 7 is a schematic view of an application scenario where a ground fault occurs between the circuit breakers FTU2-FTU3 according to an embodiment of the present invention;
fig. 8 is a schematic view of an application scenario of tripping of the circuit breakers FTU2 and FTU3 according to an embodiment of the present invention;
fig. 9 is a schematic view of an application scenario of a closing of a circuit breaker FTU2 according to an embodiment of the present invention;
fig. 10 is a schematic view of an application scenario of a closing of a circuit breaker FTU3 according to an embodiment of the present invention;
fig. 11 is a schematic structural diagram of a ground fault detection and misjudgment prevention device according to an embodiment of the present invention;
fig. 12 is a schematic diagram of an electronic device provided in an embodiment of the present invention.
Detailed Description
In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the following description is made by way of specific embodiments with reference to the accompanying drawings.
As described in the related art, the existing method for determining the ground fault by detecting whether the zero-sequence voltage-zero-sequence current occurs is prone to cause a problem of erroneous determination of the ground fault. The applicant finds that due to the existence of factors such as inductive load, capacitive load, ground capacitance, reactive compensator, transformer and the like in the power system, zero sequence voltage-zero sequence current can be generated at the closing moment of the circuit breaker, and particularly, if three phases of the circuit breaker are not closed in the same period, the power system can be operated in a non-full phase in a short time, and the zero sequence voltage-zero sequence current is easier to generate. Therefore, the mode of judging the ground fault only by detecting whether the zero sequence voltage-zero sequence current occurs is easy to judge the normal closing of the circuit breaker as the ground fault, thereby causing the circuit breaker to trip by mistake and influencing the normal operation of the power system.
In order to solve the problems in the prior art, embodiments of the present invention provide a method and an apparatus for detecting a ground fault and preventing misjudgment, and an electronic device. First, a method for preventing misjudgment of ground fault detection provided by the embodiment of the present invention is described below.
The main execution body of the method for preventing ground fault detection and false judgment may be a device for preventing ground fault detection and false judgment, and the device may be an electronic device with data processing capability, such as a ground detection device of a feeder terminal, an industrial personal computer, and other electronic devices, and the embodiment of the present invention is not limited in particular.
Referring to fig. 1, it shows an implementation flowchart of a method for detecting a ground fault and preventing an erroneous determination according to an embodiment of the present invention, which is detailed as follows:
and step 110, acquiring power data of a line where a target circuit breaker is located in the power system in real time.
In some embodiments, the power system may be any area power supply and distribution system, which may include a plurality of circuit breakers, and for convenience of description, any one of the circuit breakers in the power system is referred to below as a target circuit breaker. The power data may be zero sequence voltage data, zero sequence current data, phase voltage data, etc. of the line.
And 120, when the first sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection time, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and the first preset detection condition.
In some embodiments, the zero sequence voltage is abruptly changed, which means that the value of the zero sequence voltage is greater than the zero voltage threshold. In the prior art, whether zero sequence voltage occurs is detected, and it is actually detected whether the value of the zero sequence voltage is greater than a zero voltage threshold. Because the power system may not have one time of zero-sequence voltage mutation for a long time, or may have multiple times of zero-sequence voltage mutations for a short time, wherein the multiple times of zero-sequence voltage mutations for a short time need to be focused, in order to distinguish the two cases of a short time and a long time, the detection process may be divided into multiple detection durations, for example, according to days, hours, or minutes. Specifically, if multiple zero sequence voltage-zero sequence current sudden changes occur in a detection duration, the multiple zero sequence voltage-zero sequence current sudden changes occur in a short time, and the multiple zero sequence voltage-zero sequence current sudden changes occurring in the detection duration can be sequentially marked as first sudden changes and second sudden changes of 8230, 8230and 8230according to the occurrence sequence.
In some embodiments, the first preset detection condition may be a condition for determining whether a ground fault occurs. The applicant finds that, when the zero-sequence voltage-zero-sequence current sudden change is caused by the ground fault, the phase voltage and the phase current before the sudden change of the zero-sequence voltage are generally sine waves or cosine waves from the waveform point of view, as shown in fig. 2, before the sudden change of the zero-sequence voltage U0 and the zero-sequence current I0, the waveforms of the phase voltage UA, UB and UC are sine waves or cosine waves, and the waveforms of the phase current IA, IB and IC are sine waves or cosine waves; from the perspective of the phase voltage effective value, the voltage effective value of each phase line is usually within an allowable fluctuation range of the normal phase voltage effective value of the power grid before sudden change.
From the view of waveforms, as shown in fig. 3, phase voltages and phase currents before the zero-sequence voltage sudden change generally have no waveforms, that is, coincide with the reference line, or are waveforms irregularly fluctuating above and below the reference line, as shown in fig. 3, and before the zero-sequence voltage U0 and the zero-sequence current I0 sudden change, the phase voltages UA, UB, UC and the phase currents IA, IB, IC have no waveforms; from the perspective of the effective value of the phase voltage, the effective value of the voltage of each phase line is usually zero before sudden change, or is far lower than the lower limit value of the allowable fluctuation interval of the effective value of the normal phase voltage of the power grid.
It should be noted that the actual fluctuation interval of the effective voltage value of each phase line of the power grid is usually related to the size of the power supply capacitor of the power grid, the quality of the power transmission and distribution equipment, the amount of the power consumption capacity, and the like, in cities and industrial parks with better power supply conditions, the fluctuation interval is usually within plus or minus 15%, namely 85% -115% of the rated voltage of the power grid, and in rural and remote areas with poorer power supply conditions, the variation range is much larger, and sometimes even reaches 20% -30%.
Based on this, a first preset detection condition may be set. For example, the first preset detection condition may be that the number of zero-crossings of the phase voltage in a period before and closest to the abrupt change is not equal to two, where the number of zero-crossings refers to the number of zero-crossings that the waveform has in a single period, as shown in fig. 4, and a point 40 where the waveform of the phase voltage crosses a reference line is a zero-crossing point. For another example, the first preset detection condition may be that the phase voltage effective value of a period before and closest to the sudden change is smaller than a preset voltage threshold, where the preset voltage threshold may be set according to an allowable fluctuation interval of the normal phase voltage effective value, for example, a voltage value corresponding to 70%, 60%, or 30% of the rated voltage of the power grid may be set as the preset voltage threshold. Taking the rated voltage of the power grid as 100V as an example, when the preset voltage threshold is set to 70% of the rated voltage of the power grid, the preset voltage threshold is 70V.
In one possible implementation, the power data may include phase voltage data, which may be voltage data of any phase in the line in which the circuit breaker is located, and the phase voltage data may be a-phase voltage data, B-phase voltage data, or C-phase voltage data, for example, in a three-phase four-wire system. The first preset detection condition may be that the number of zero-crossings of the phase voltage of a period before and closest to the abrupt change is not equal to two, and accordingly, the process of step 120 may be as follows: zero crossing points of the phase voltage in a period which is before and closest to the first sudden change of the phase voltage; and if the number of the obtained phase voltage zero-crossing points is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
Specifically, when the execution main body detects that the zero sequence voltage of the line where the target circuit breaker is located suddenly changes for the first time within a certain detection duration, the zero crossing number of the phase voltage in a period before the sudden change for the first time and closest to the sudden change for the first time can be obtained based on the phase voltage data collected in real time, wherein the period can be the waveform period of the phase voltage. And then, the execution main body detects the zero-crossing point number of the phase voltage by using a first preset detection condition, if the zero-crossing point number of the voltage is not equal to two, the zero-sequence voltage mutation is indicated to be caused by the closing of the circuit breaker and no ground fault occurs, and at the moment, a detection result that the ground fault does not occur on a line where the target circuit breaker is located can be generated. If the zero-crossing point number of the phase voltage is equal to two, the zero-sequence voltage mutation is indicated to be caused not by the switching-on of the circuit breaker but by the ground fault, and at the moment, a detection result that the ground fault occurs to the circuit where the target circuit breaker is located can be generated.
In one possible implementation, the power data may include phase voltage data, which may be voltage data for any phase in the line in which the circuit breaker is located. Taking a three-phase four-wire system as an example, the phase voltage data may be a-phase voltage data, B-phase voltage data, or C-phase voltage data. The first preset detection condition may be that the effective value of the phase voltage of the period before and closest to the abrupt change is smaller than the preset voltage threshold, and accordingly, the processing of step 120 may be as follows: acquiring a phase voltage effective value of a period which is before and closest to the first mutation of the phase voltage; and if the phase voltage effective value is smaller than the preset voltage threshold value, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
Specifically, when detecting a zero sequence voltage sudden change of a line where the target circuit breaker is located, the execution main body may obtain, based on phase voltage data collected in real time, a phase voltage effective value of a period of the phase voltage before the first sudden change and closest to the first sudden change, where the period may be a waveform period of the phase voltage. And then, the execution main body detects the phase voltage effective value by using a first preset detection condition, if the phase voltage effective value is smaller than a preset voltage threshold value, the zero sequence voltage mutation is caused by the closing of the circuit breaker and no ground fault occurs, and at the moment, a detection result that the ground fault does not occur in the circuit where the target circuit breaker is located can be generated. If the phase voltage effective value is larger than or equal to the preset voltage threshold value, it is indicated that the zero sequence voltage mutation is caused by the earth fault instead of the circuit breaker closing, and at the moment, a detection result of the earth fault of the circuit where the target circuit breaker is located can be generated.
It is worth mentioning that as long as the effective value of the phase voltage of any phase meets the first preset detection condition, a detection result of the ground fault of the line where the target circuit breaker is located can be generated. For example, if the phase voltage effective value of the a-phase satisfies the first preset detection condition and the phase voltage effective value of the B-phase and the C-phase does not satisfy the first preset detection condition, the detection result of the ground fault of the line where the target circuit breaker is located may still be generated.
In a possible implementation manner, considering that the power grid fluctuation caused by closing the circuit breaker may last for a period of time, and a zero sequence voltage sudden change may occur again within the period of time, in order to save detection resources and ensure detection accuracy, the occurrence source of the sudden change may be determined by a preset time threshold, and after step 120, as shown in fig. 5, the following processing may be further performed:
and step 130, when the second sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection duration, acquiring the time difference between the second sudden change time and the first sudden change time.
In some embodiments, the execution subject may record and store the time when the sudden change occurs when the sudden change is detected. Therefore, when the execution main body detects the second sudden change of the zero sequence voltage of the circuit where the target circuit breaker is located within the same detection duration, the time of the second sudden change can be obtained, and then the time difference between the time of the second sudden change and the time of the first sudden change is obtained according to the stored time of the first sudden change.
And 140, if the time difference is smaller than the preset time threshold, not performing ground fault detection on the second sudden change, otherwise, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a second preset detection condition.
In some embodiments, after a lot of tests, the applicant finds that the grid fluctuation caused by the closing of the breaker is usually maintained at about 30 milliseconds and usually does not exceed 40 milliseconds, and then the zero sequence voltage caused by the closing of the breaker is suddenly changed again and should appear during the grid fluctuation, for this reason, the time of the grid fluctuation can be referred to by a preset time threshold, and according to the detection cost and accuracy requirements, a suitable preset time threshold is selected, such as 50 milliseconds or 40 milliseconds, and the like, and is not limited herein.
Specifically, if the time difference between the time of the second sudden change and the time of the first sudden change is smaller than the preset time threshold, it indicates that the sudden change occurs during the grid fluctuation, and the ground fault detection may not be performed on the second sudden change, so as to save detection resources. If the time difference between the time of the second sudden change and the time of the first sudden change is larger than or equal to the preset time threshold, the sudden change is not caused by the last circuit breaker switching-on, the sudden change may be a ground fault or another circuit breaker switching-on, and therefore whether the ground fault is sent or not can be judged according to the power data collected in real time and the second preset detection condition.
In some embodiments, similar to the first preset detection condition, the second preset detection condition is also a condition for determining whether a ground fault occurs, except that the time interval between the second sudden change and the first sudden change may be shorter, and in the case that the time interval between the two sudden changes is shorter, the effective value of the phase voltage before the second sudden change is usually not zero and may be greater than the preset voltage threshold, for which, if the detection is performed by the preset voltage threshold alone, the accuracy may be lower. Therefore, the judgment processing corresponding to the number of zero-crossings of the voltage may be used as the second preset detection condition, or the judgment processing combining the number of zero-crossings of the voltage and the preset voltage threshold may be used as the second preset detection condition.
In one possible implementation, the power data may include phase voltage data, and the second preset detection condition may be that the number of zero crossings of the phase voltage of one period located before and closest to the abrupt change is not equal to two, so that the processing of step 140 may be as follows: acquiring the number of phase voltage zero-crossing points of a phase voltage in a period which is before the second sudden change and is closest to the second sudden change; and if the zero-crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data may include phase voltage data, and accordingly, the second preset detection condition may be that the effective value of the phase voltage in a period before and closest to the abrupt change is smaller than a preset voltage threshold, and the number of zero-crossings of the phase voltage in a period before and closest to the abrupt change is not equal to two, and accordingly, the processing of step 140 may be as follows: acquiring a phase voltage effective value of a phase voltage in a period which is positioned before the second time mutation and is closest to the second time mutation, and acquiring a phase voltage zero-crossing point number of the phase voltage in a period which is positioned before the second time mutation and is closest to the second time mutation; and if the phase voltage effective value is smaller than the preset voltage threshold value and the phase voltage zero-crossing point number is not equal to two, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
It should be noted that, in the detection process using the second preset detection condition, reference may be made to the detection process using the first preset detection condition, which is not described herein again.
Therefore, through the detection processing of the ground fault, the zero sequence voltage-zero sequence current mutation caused by the normal closing of the circuit breaker can be detected, so that the problem that the normal closing of the circuit breaker is judged as the ground fault by mistake is solved, the false tripping of the circuit breaker is avoided, and the ground fault detection accuracy is higher.
An application scenario is provided below, taking the power system including the circuit breakers FTU1-FTU6 as an example.
Referring to fig. 6, the circuit breakers FTU1 to FTU6 are all in a closing state, and the line operates normally. Referring to fig. 7, when a ground fault occurs between the circuit breakers FTU2-FTU3, grounding logic is activated to control the circuit breakers FTU2 and FTU3 to trip to remove the fault, as shown in fig. 8. After the earth fault between the circuit breakers FTU2 and FTU3 is eliminated, and the FTU2 and the FTU3 are in the open state and have no fault, the circuit breaker FTU2 is controlled to be switched on, at the moment, the zero sequence voltage-zero sequence current of the circuit breaker FTU2 is detected, and after the earth fault detection anti-misjudgment method provided by the invention is adopted, the earth fault can be judged not to be generated, so that the circuit breaker FTU2 can be switched on successfully as shown in fig. 9. Similarly, as shown in fig. 10, the circuit breaker FTU3 is successfully switched on, so that the circuit breakers FTU1 to FTU6 are both in a switched-on state again, and the line operates normally.
In the embodiment of the invention, a ground fault detection scheme is provided, which can judge whether the sudden change is caused by the ground fault or the closing of the circuit breaker according to the preset detection condition when the zero-sequence voltage sudden change is detected, so that the problem that the normal closing of the circuit breaker is wrongly judged as the ground fault is solved, the wrong tripping of the circuit breaker is avoided, and the ground fault detection accuracy is higher.
It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.
The following are embodiments of the apparatus of the invention, reference being made to the corresponding method embodiments described above for details which are not described in detail therein.
Fig. 11 is a schematic structural diagram of a ground fault detection erroneous-judgment prevention device according to an embodiment of the present invention, and for convenience of description, only the portions related to the embodiment of the present invention are shown, and detailed descriptions are as follows:
as shown in fig. 11, the ground fault detection erroneous judgment prevention device includes:
the acquisition module 1110 is configured to acquire power data of a line in which a target circuit breaker is located in a power system in real time;
the detection module 1120 is configured to generate a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a first preset detection condition when a first sudden change of the zero-sequence voltage of the line where the target circuit breaker is located is detected within a detection time period; the first preset detection condition is that the number of zero-crossing points of the phase voltage of one period which is located before and nearest to the sudden change is not equal to two, or the effective value of the phase voltage of one period which is located before and nearest to the sudden change is smaller than a preset voltage threshold value.
In one possible implementation, the power data includes phase voltage data; the first preset detection condition is that the number of zero-crossing points of the phase voltage of a period which is positioned before the mutation and is closest to the mutation is not equal to two;
the detection module is further configured to:
acquiring the number of phase voltage zero-crossing points of a phase voltage in a period which is before the first mutation and is closest to the first mutation; and if the zero-crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data includes phase voltage data; the first preset detection condition is that the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value;
the detection module is further configured to:
acquiring a phase voltage effective value of a period which is before and closest to the first mutation of the phase voltage; and if the phase voltage effective value is smaller than the preset voltage threshold value, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the detection module is further configured to:
when the second sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection duration, acquiring the time difference between the time of the second sudden change and the time of the first sudden change;
and if the time difference is smaller than the preset time threshold, not performing ground fault detection on the second sudden change, otherwise, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a second preset detection condition.
In one possible implementation, the power data includes phase voltage data; the second preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is positioned before the mutation and is closest to the mutation is not equal to two;
the detection module is further configured to:
acquiring the zero crossing number of the phase voltage in a period which is before the second mutation and is closest to the second mutation;
and if the zero crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
In one possible implementation, the power data includes phase voltage data; the second preset detection condition is that the effective value of the phase voltage of a period which is before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value, and the number of zero-crossing points of the phase voltage of a period which is before the sudden change and is closest to the sudden change is not equal to two;
the detection module is further configured to:
acquiring a phase voltage effective value of a phase voltage in a period which is positioned before the second time mutation and is closest to the second time mutation, and acquiring a phase voltage zero-crossing point number of the phase voltage in a period which is positioned before the second time mutation and is closest to the second time mutation;
and if the phase voltage effective value is smaller than the preset voltage threshold value and the phase voltage zero-crossing point number is not equal to two, generating a detection result that the line where the target circuit breaker is located does not have the ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
Fig. 12 is a schematic diagram of an electronic device provided in an embodiment of the present invention. As shown in fig. 12, the electronic apparatus 12 of this embodiment includes: a processor 120, a memory 121, and a computer program 122 stored in the memory 121 and executable on the processor 120. The processor 120 executes the computer program 122 to implement the steps of the above-mentioned embodiments of the ground fault detection anti-misjudgment method, such as the steps 110 to 120 shown in fig. 1. Alternatively, the processor 120, when executing the computer program 122, implements the functions of the modules in the above-described device embodiments, such as the functions of the modules 1110 to 1120 shown in fig. 11.
Illustratively, the computer program 122 may be partitioned into one or more modules, which are stored in the memory 121 and executed by the processor 120 to implement the present invention. The one or more modules may be a series of computer program instruction segments capable of performing certain functions that are used to describe the execution of the computer program 122 on the electronic device 12. For example, the computer program 122 may be divided into modules 1110 to 1120 shown in fig. 11.
The electronic device 12 may include, but is not limited to, a processor 120, a memory 121. Those skilled in the art will appreciate that fig. 12 is merely an example of electronic device 12 and does not constitute a limitation of electronic device 12 and may include more or fewer components than shown, or some components may be combined, or different components, e.g., the electronic device may also include input-output devices, network access devices, buses, etc.
The Processor 120 may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
The storage 121 may be an internal storage unit of the electronic device 12, such as a hard disk or a memory of the electronic device 12. The memory 121 may also be an external storage device of the electronic device 12, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like, which are provided on the electronic device 12. Further, the memory 121 may also include both an internal storage unit and an external storage device of the electronic device 12. The memory 121 is used for storing the computer program and other programs and data required by the electronic device. The memory 121 may also be used to temporarily store data that has been output or is to be output.
It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only used for distinguishing one functional unit from another, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the above embodiments, the description of each embodiment has its own emphasis, and reference may be made to the related description of other embodiments for parts that are not described or recited in any embodiment.
Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
In the embodiments provided in the present invention, it should be understood that the disclosed apparatus/electronic device and method may be implemented in other ways. For example, the above-described apparatus/electronic device embodiments are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implemented, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated module/unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, all or part of the flow of the method according to the above embodiments may be implemented by a computer program, which may be stored in a computer readable storage medium, and when the computer program is executed by a processor, the steps of the above embodiments of the method for detecting ground fault and preventing false alarm may be implemented. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U.S. disk, removable hard disk, magnetic diskette, optical disk, computer Memory, read-Only Memory (ROM), random Access Memory (RAM), electrical carrier wave signal, telecommunications signal, and software distribution medium, etc. It should be noted that the computer readable medium may contain other components which may be suitably increased or decreased as required by legislation and patent practice in jurisdictions, for example, in some jurisdictions, computer readable media which may not include electrical carrier signals and telecommunications signals in accordance with legislation and patent practice.
The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention.
Claims (8)
1. A ground fault detection anti-misjudgment method is characterized by comprising the following steps:
acquiring power data of a line where a target circuit breaker is located in a power system in real time;
when the first time mutation of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection duration, generating a ground fault detection result of the line where the target circuit breaker is located according to the power data and a first preset detection condition; the first preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before and closest to the mutation is not equal to two;
when the power data includes phase voltage data and the first preset detection condition is that the number of phase voltage zero-crossings of a period which is located before the sudden change and is closest to the sudden change is not equal to two, generating a ground fault detection result of a line where the target circuit breaker is located according to the power data and the first preset detection condition includes:
acquiring the number of phase voltage zero-crossing points of a phase voltage in a period which is before the first mutation and is closest to the first mutation; and if the zero crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
2. The ground fault detection false positive method according to claim 1, wherein the power data includes phase voltage data; the first preset detection condition is that the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value;
the generating a ground fault detection result of the line where the target circuit breaker is located according to the power data and a first preset detection condition comprises:
acquiring a phase voltage effective value of a period which is before and closest to the first mutation of the phase voltage;
and if the effective value of the phase voltage is smaller than the preset voltage threshold, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
3. The ground fault detection false-proof method according to claim 1, wherein after generating the ground fault detection result of the line on which the target circuit breaker is located, the method further comprises:
when the second mutation of the zero sequence voltage of the line where the target circuit breaker is located is detected within the detection duration, acquiring a time difference between the time of the second mutation and the time of the first mutation;
and if the time difference is smaller than a preset time threshold, not performing ground fault detection on the second sudden change, otherwise, generating a ground fault detection result of the line where the target circuit breaker is located according to the electric power data and a second preset detection condition.
4. The ground fault detection false-proof method according to claim 3, wherein the power data includes phase voltage data; the second preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before the sudden change and is closest to the sudden change is not equal to two;
generating a ground fault detection result of the line where the target circuit breaker is located according to the power data and a second preset detection condition, wherein the ground fault detection result comprises:
acquiring the zero crossing number of the phase voltage in a period which is before the second mutation and is closest to the second mutation;
and if the zero crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
5. The ground fault detection false-proof method according to claim 3, wherein the power data includes phase voltage data; the second preset detection condition is that the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value, and the number of zero-crossing points of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is not equal to two;
the generating a ground fault detection result of the line where the target circuit breaker is located according to the power data and a second preset detection condition comprises:
acquiring a phase voltage effective value of a phase voltage in a period which is before the second sudden change and is closest to the second sudden change, and acquiring a phase voltage zero-crossing point number of the phase voltage in a period which is before the second sudden change and is closest to the second sudden change;
and if the effective value of the phase voltage is smaller than the preset voltage threshold value and the zero-crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
6. The utility model provides a ground fault detects prevents erroneous judgement device which characterized in that includes:
the acquisition module is used for acquiring the power data of a line where a target circuit breaker is located in the power system in real time;
the detection module is used for generating a ground fault detection result of the line where the target circuit breaker is located according to the power data and a first preset detection condition when the first sudden change of the zero sequence voltage of the line where the target circuit breaker is located is detected within a detection time period; the first preset detection condition is that the number of zero-crossing points of the phase voltage in a period which is before and closest to the mutation is not equal to two;
the detection module is further configured to:
under the condition that the electric power data comprise phase voltage data and the first preset detection condition is that the number of phase voltage zero-crossing points of a period which is positioned before the sudden change and is closest to the sudden change is not equal to two, acquiring the number of phase voltage zero-crossing points of a period which is positioned before the first sudden change and is closest to the first sudden change; and if the zero crossing point number of the phase voltage is not equal to two, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
7. The ground fault detection false-judgment preventing device according to claim 6, wherein the power data includes phase voltage data; the first preset detection condition is that the effective value of the phase voltage of a period which is positioned before the sudden change and is closest to the sudden change is smaller than a preset voltage threshold value;
the detection module is further configured to:
acquiring a phase voltage effective value of a period which is before and closest to the first mutation of the phase voltage; and if the effective value of the phase voltage is smaller than the preset voltage threshold, generating a detection result that the line where the target circuit breaker is located has no ground fault, otherwise, generating a detection result that the line where the target circuit breaker is located has the ground fault.
8. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the ground fault detection false positive method as claimed in any one of claims 1 to 5 above when executing the computer program.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101846716A (en) * | 2009-03-27 | 2010-09-29 | 北海银河科技继保电气有限公司 | Method for quickly catching power grid fault start point |
| CN101867178A (en) * | 2010-03-30 | 2010-10-20 | 昆明理工大学 | Fault location method using three primary colours to represent travel waves of single-phase earth fault current of transmission line |
| CN102385020A (en) * | 2010-08-20 | 2012-03-21 | 施耐德电器工业公司 | Directional detection of an earth fault with a single sensor |
| CN102955098A (en) * | 2012-12-10 | 2013-03-06 | 四川省电力公司资阳公司 | Neutral point non-effective earthing system single-phase earthing fault identification method |
| CN110069886A (en) * | 2019-05-05 | 2019-07-30 | 四川大学 | The identification of cable initial failure and classification method based on VMD and CNN |
| CN111751667A (en) * | 2020-06-29 | 2020-10-09 | 深圳供电局有限公司 | Method and system for judging current transformer saturation based on power grid fault recording diagram |
| CN113128153A (en) * | 2021-04-20 | 2021-07-16 | 合肥工业大学 | Active frequency conversion fault recording method triggered by composite threshold in photovoltaic power station |
| CN113391164A (en) * | 2021-06-10 | 2021-09-14 | 中国电力科学研究院有限公司 | Intelligent identification method and device for single-phase earth fault of power distribution network |
| CN114188946A (en) * | 2021-11-23 | 2022-03-15 | 中国电力科学研究院有限公司 | Method and system for processing abnormal frequency of new energy station under broadband harmonic working condition |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109212338B (en) * | 2017-06-30 | 2021-04-20 | 施耐德电器工业公司 | Power island detection method and device and computer readable storage medium |
| CN115089196B (en) * | 2022-08-22 | 2022-11-11 | 博睿康科技（常州）股份有限公司 | Time phase detection method, time phase detection unit and closed-loop regulation and control system of online signal |
-
2022
- 2022-09-08 CN CN202211092152.XA patent/CN115166585B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101846716A (en) * | 2009-03-27 | 2010-09-29 | 北海银河科技继保电气有限公司 | Method for quickly catching power grid fault start point |
| CN101867178A (en) * | 2010-03-30 | 2010-10-20 | 昆明理工大学 | Fault location method using three primary colours to represent travel waves of single-phase earth fault current of transmission line |
| CN102385020A (en) * | 2010-08-20 | 2012-03-21 | 施耐德电器工业公司 | Directional detection of an earth fault with a single sensor |
| CN102955098A (en) * | 2012-12-10 | 2013-03-06 | 四川省电力公司资阳公司 | Neutral point non-effective earthing system single-phase earthing fault identification method |
| CN110069886A (en) * | 2019-05-05 | 2019-07-30 | 四川大学 | The identification of cable initial failure and classification method based on VMD and CNN |
| CN111751667A (en) * | 2020-06-29 | 2020-10-09 | 深圳供电局有限公司 | Method and system for judging current transformer saturation based on power grid fault recording diagram |
| CN113128153A (en) * | 2021-04-20 | 2021-07-16 | 合肥工业大学 | Active frequency conversion fault recording method triggered by composite threshold in photovoltaic power station |
| CN113391164A (en) * | 2021-06-10 | 2021-09-14 | 中国电力科学研究院有限公司 | Intelligent identification method and device for single-phase earth fault of power distribution network |
| CN114188946A (en) * | 2021-11-23 | 2022-03-15 | 中国电力科学研究院有限公司 | Method and system for processing abnormal frequency of new energy station under broadband harmonic working condition |
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|---|---|
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