CN114878973A - Multi-branch distribution line lightning stroke fault positioning method and device and storage medium - Google Patents

Multi-branch distribution line lightning stroke fault positioning method and device and storage medium Download PDF

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CN114878973A
CN114878973A CN202210654586.8A CN202210654586A CN114878973A CN 114878973 A CN114878973 A CN 114878973A CN 202210654586 A CN202210654586 A CN 202210654586A CN 114878973 A CN114878973 A CN 114878973A
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lightning
interval
lightning stroke
monitoring
lightning current
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肖小兵
廖民传
刘安茳
冯瑞发
蔡永翔
屈路
付宇
刘刚
李跃
祁汭晗
王扬
李龙桂
郝树青
苗宇
何肖蒙
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China South Power Grid International Co ltd
Guizhou Power Grid Co Ltd
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China South Power Grid International Co ltd
Guizhou Power Grid Co Ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08Locating faults in cables, transmission lines, or networks
    • G01R31/081Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/085Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08Locating faults in cables, transmission lines, or networks
    • G01R31/088Aspects of digital computing
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/20Design optimisation, verification or simulation
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2113/00Details relating to the application field
    • G06F2113/04Power grid distribution networks
    • YGENERAL 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
    • Y04INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04SSYSTEMS 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
    • Y04S10/00Systems supporting electrical power generation, transmission or distribution
    • Y04S10/50Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
    • Y04S10/52Outage or fault management, e.g. fault detection or location

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  • General Engineering & Computer Science (AREA)
  • Mathematical Physics (AREA)
  • Locating Faults (AREA)

Abstract

The invention relates to the technical field of lightning protection of power transmission and distribution lines, and discloses a method and a device for positioning lightning stroke faults of a multi-branch power distribution line and a storage medium. The lightning current amplitude attenuation rule of the multi-branch power distribution line and the lightning current polarity relation on the main line are analyzed according to distributed monitoring data of the multi-branch power distribution line to determine a lightning stroke interval, target monitoring points are determined according to the size of a lightning current peak value collected by a distributed lightning current monitoring terminal in the lightning stroke interval, wavelet transformation is carried out on lightning current waveform data corresponding to each target monitoring point, the time point when a wavelet transformation maximum value appears is taken as the arrival time of lightning stroke fault traveling waves, the distance from a lightning stroke fault point to the corresponding target monitoring point is calculated to determine a lightning stroke fault point set corresponding to each target monitoring point, intersection is obtained for all the determined lightning stroke fault point sets, and false lightning stroke fault points are eliminated. The lightning stroke fault locating method and the lightning stroke fault locating device can realize rapid and accurate locating and identification of the lightning stroke fault of the multi-branch distribution line.

Description

Multi-branch distribution line lightning stroke fault positioning method and device and storage medium
Technical Field
The invention relates to the technical field of lightning protection of power transmission and distribution lines, in particular to a method and a device for positioning lightning stroke faults of a multi-branch power distribution line and a storage medium.
Background
Lightning strike always represents an important threat to the safe and stable operation of a power system, wherein 60-70% of tripping phenomena of an overhead transmission line are caused by the lightning strike. Compared with an overhead transmission line, the multi-branch distribution line has higher probability of power supply interruption caused by lightning stroke due to factors such as low insulation level, wide line distribution, poor tower grounding condition and the like.
At present, the lightning stroke fault positioning method for the overhead transmission line is researched more mature at home and abroad, and the lightning stroke fault positioning and identifying technology for the multi-branch distribution line is rarely researched. The lightning stroke fault location of the overhead transmission line mostly adopts a traveling wave theory, the multi-branch distribution line generally consists of complex multi-branch lines, the complex traveling wave catadioptric is generated by the multi-branch lines after the overhead transmission line is struck by lightning, the monitored waveform and parameters are greatly different from those of the transmission line, and the fault point can not be quickly and accurately located by simply applying the traditional traveling wave theory.
Therefore, there is a need to provide a solution that can quickly and accurately locate and identify lightning strike faults on multi-branch distribution lines.
Disclosure of Invention
The invention provides a multi-branch distribution line lightning stroke fault positioning method, a multi-branch distribution line lightning stroke fault positioning device and a multi-branch distribution line lightning stroke fault storage medium, and solves the technical problem of how to quickly and accurately position and identify the lightning stroke fault of the multi-branch distribution line.
The invention provides a multi-branch distribution line lightning stroke fault positioning method, wherein a plurality of monitoring points are arranged on a main line of the multi-branch distribution line at intervals, a monitoring point is arranged on a branch line, and each monitoring point is provided with a distributed lightning current monitoring terminal, the method comprises the following steps:
acquiring lightning current waveform data acquired by each distributed lightning current monitoring terminal, analyzing a lightning current amplitude attenuation rule of a multi-branch distribution line and a lightning current polarity relation on a main line according to the lightning current waveform data, and determining a lightning stroke interval according to an obtained analysis result;
screening target monitoring points from all monitoring points in the lightning stroke interval according to the magnitude of lightning current peak values collected by distributed lightning current monitoring terminals in the lightning stroke interval;
performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point, taking the time point of occurrence of a wavelet transformation maximum value as the arrival time of lightning fault traveling waves, and calculating the distance from the lightning fault point to the corresponding target monitoring point;
and determining a lightning stroke fault point set corresponding to each target monitoring point according to the distance from the lightning stroke fault point to the corresponding target monitoring point, solving the intersection of all the determined lightning stroke fault point sets, and taking the obtained intersection result as the lightning stroke fault point of the multi-branch distribution line.
According to a manner of the first aspect of the present invention, the determining a lightning stroke interval according to the obtained analysis result includes:
taking the interval of two adjacent monitoring points on the main line as a monitoring interval, and determining the interval type of each monitoring interval according to the number of branch lines connected with the main line section in the monitoring interval, wherein the interval types comprise an interval without connecting branch lines on the main line section, an interval with one branch line connected with the main line section and an interval with a plurality of branch lines connected with the main line section;
calculating the average value of the lightning current amplitude attenuation rate corresponding to each interval type according to the lightning current amplitude attenuation rule, calculating the difference value between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rate corresponding to the interval type, and taking the monitoring interval with the difference value larger than a preset threshold value as an alternative lightning stroke interval;
and determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line.
According to a manner that can be realized in the first aspect of the present invention, the screening out a target monitoring point from each monitoring point in the lightning stroke interval according to the magnitude of the lightning current peak value collected by the distributed lightning current monitoring terminal in the lightning stroke interval includes:
sequencing corresponding monitoring points according to the sequence of the lightning current peak values collected by the distributed lightning current monitoring terminals in the lightning stroke interval from large to small;
and selecting N monitoring points in the front of the sequence as target monitoring points, wherein N is less than N, and N is the number of the monitoring points in the lightning stroke interval.
According to an enabling aspect of the first aspect of the invention, the method further comprises:
determining lightning current waveform characteristics and change rules of the multi-branch distribution line under lightning strokes of different lightning stroke types through simulation analysis, and extracting typical characteristics for identifying the lightning stroke types according to the lightning current waveform characteristics and the change rules;
lightning current waveform characteristics corresponding to the lightning stroke interval are extracted, and the extracted lightning current waveform characteristics are compared with each typical characteristic to determine the type of lightning stroke;
and if the determined lightning stroke type is induction lightning or direct lightning, judging whether the line on the lightning stroke interval has flashover or not, and outputting a corresponding line flashover judgment result.
The second aspect of the present invention provides a multi-branch distribution line lightning stroke fault locating device, where multiple monitoring points are arranged at intervals on a main line of the multi-branch distribution line, a monitoring point is arranged on a branch line, and each monitoring point is provided with a distributed lightning current monitoring terminal, the device including:
the lightning stroke interval determining module is used for acquiring lightning current waveform data acquired by each distributed lightning current monitoring terminal, analyzing the lightning current amplitude attenuation rule of the multi-branch distribution line and the lightning current polarity relation on the main line according to the lightning current waveform data, and determining a lightning stroke interval according to the obtained analysis result;
the target monitoring point screening module is used for screening target monitoring points from all monitoring points in the lightning stroke interval according to the lightning current peak value acquired by the distributed lightning current monitoring terminals in the lightning stroke interval;
the lightning stroke fault point distance calculation module is used for performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point, taking a time point of occurrence of a wavelet transformation maximum value as the arrival time of a lightning stroke fault traveling wave, and calculating the distance from the lightning stroke fault point to the corresponding target monitoring point;
and the lightning stroke fault point positioning module is used for determining a lightning stroke fault point set corresponding to each target monitoring point according to the distance from the lightning stroke fault point to the corresponding target monitoring point, solving an intersection of all the determined lightning stroke fault point sets, and taking an obtained intersection result as the lightning stroke fault point of the multi-branch distribution line.
According to an implementable manner of the second aspect of the invention, the lightning stroke interval determination module comprises:
the section classification unit is used for taking the section of two adjacent monitoring points on the main line as a monitoring section, and determining the section type of each monitoring section according to the number of branch lines connected with the main line section in the monitoring section, wherein the section types comprise the section of the main line section without connecting branch lines, the section of the main line section with one branch line and the section of the main line section with a plurality of branch lines;
the first interval determining unit is used for calculating the average value of the lightning current amplitude attenuation rate corresponding to each interval type according to the lightning current amplitude attenuation rule, calculating the difference value between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rate corresponding to the interval type, and taking the monitoring interval with the difference value larger than a preset threshold value as an alternative lightning stroke interval;
and the second interval determining unit is used for determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line.
According to a manner that the second aspect of the present invention can be realized, the target monitoring point screening module includes:
the monitoring point sorting unit is used for sorting the corresponding monitoring points according to the sequence of the lightning current peak values collected by the distributed lightning current monitoring terminals in the lightning stroke interval from large to small;
and the monitoring point screening unit is used for selecting N monitoring points before sorting as target monitoring points, wherein N is less than N, and N is the number of the monitoring points in the lightning stroke interval.
According to an implementable manner of the second aspect of the invention, the apparatus further comprises:
the simulation analysis module is used for determining lightning current waveform characteristics and change rules of the multi-branch distribution line under lightning strokes of different lightning stroke types through simulation analysis, and extracting typical characteristics for identifying the lightning stroke types according to the lightning current waveform characteristics and the change rules;
the lightning type determining module is used for extracting lightning current waveform characteristics corresponding to the lightning stroke interval and comparing the extracted lightning current waveform characteristics with each typical characteristic to determine the lightning stroke type;
and the line flashover judging module is used for judging whether the line on the lightning stroke interval has flashover or not and outputting a corresponding line flashover judging result when the determined lightning stroke type is induction lightning or direct lightning.
The third aspect of the present invention provides a lightning stroke fault locating device for a multi-branch distribution line, comprising:
a memory to store instructions; the instructions are used for realizing the multi-branch distribution line lightning stroke fault positioning method in any one realizable mode;
a processor to execute the instructions in the memory.
A fourth aspect of the present invention is a computer-readable storage medium having a computer program stored thereon, where the computer program, when executed by a processor, implements a method for locating a lightning strike fault on a multi-branch distribution line as described in any one of the above-mentioned manners.
According to the technical scheme, the invention has the following advantages:
the invention monitors the multi-branch distribution line by a distributed lightning current monitoring mode, analyzes the relationship between the lightning current amplitude attenuation rule of the multi-branch distribution line and the lightning current polarity on the main line according to the monitored lightning current waveform data, determines a lightning stroke interval according to the obtained analysis result, screens out target monitoring points from each monitoring point in the lightning stroke interval according to the size of the lightning current peak value collected by a distributed lightning current monitoring terminal in the lightning stroke interval, further performs wavelet transformation on the lightning current waveform data corresponding to each target monitoring point, takes the time point of the occurrence of the wavelet maximum transformation value as the arrival time of lightning stroke fault traveling waves, calculates the distance from the lightning stroke fault point to the corresponding target monitoring point, finally determines the lightning stroke fault point set corresponding to each target monitoring point according to the calculated distance, and finds the intersection of all the determined lightning stroke fault point sets, taking the obtained intersection result as a lightning stroke fault point of the multi-branch distribution line; the lightning stroke interval is determined by combining the lightning current amplitude attenuation rule of the multi-branch power distribution line and the lightning current polarity relation on the main line, the accuracy of determining the lightning stroke interval can be improved, the target monitoring points are screened out from all monitoring points in the lightning stroke interval, the lightning stroke fault point is positioned according to the lightning stroke fault point set of the target monitoring points, the efficiency is improved in comparison with the mode of positioning the lightning stroke fault point by using the lightning stroke fault point set of all monitoring points in the lightning stroke interval, finally, the false lightning stroke fault point is searched in a mode of finding intersection of the determined lightning stroke fault point set, the accuracy of positioning the lightning stroke fault point is further improved, therefore, the lightning stroke fault of the multi-branch power distribution line can be quickly and accurately positioned and identified, and a foundation is provided for quickly searching the fault of the multi-branch 10kV power distribution network and quickly recovering power supply.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art 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 for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.
Fig. 1 is a schematic layout diagram of distributed lightning current monitoring terminals of a distributed monitoring system on a multi-branch distribution line according to an alternative embodiment of the present invention;
FIG. 2 is a flow chart of a method for locating a lightning strike fault on a multi-branch distribution line according to an alternative embodiment of the invention;
FIG. 3 is a flowchart of a method for locating a lightning strike fault on a multi-branch distribution line according to another alternative embodiment of the invention;
FIG. 4 is a block diagram illustrating structural connections of a multi-branch distribution line lightning strike fault location apparatus according to an alternative embodiment of the present invention;
fig. 5 is a block diagram illustrating structural connections of a multi-branch distribution line lightning strike fault location apparatus according to an alternative embodiment of the invention.
Reference numerals are as follows:
1-a lightning stroke interval determination module; 2-a target monitoring point screening module; 3-lightning stroke fault point distance calculating module; 4-lightning stroke fault point positioning module; 5-a simulation analysis module; 6-a lightning stroke type determination module; 7-line flashover judgment module.
Detailed Description
The embodiment of the invention provides a multi-branch distribution line lightning stroke fault positioning method, a multi-branch distribution line lightning stroke fault positioning device and a storage medium, which are used for solving the technical problem of how to quickly and accurately position and identify the lightning stroke fault of the multi-branch distribution line.
In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the embodiments described below are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that the present invention is based on a distributed monitoring system, that is, when the method and apparatus of the present invention are executed, a plurality of monitoring points are arranged at intervals on the main line of the multi-branch power distribution line where lightning stroke fault location is required, one monitoring point is arranged on a branch line, and a distributed lightning current monitoring terminal is arranged on each monitoring point, as shown in fig. 1, M is arranged on the main line of the multi-branch power distribution line 1 ,M 2 ,…,M w Each branch line is provided with a distributed lightning current monitoring terminal which is sequentially N 1 ,N 2 ,…,N w . The lightning stroke fault positioning method is used for positioning the lightning stroke fault of the multi-branch distribution line based on the data of the distributed lightning current monitoring terminal. Distributed lightning current monitor for ensuring data collection effectivenessThe test terminal should meet the bandwidth requirement, and all distributed lightning current monitoring terminals are enabled to achieve clock synchronization.
The invention provides a lightning stroke fault positioning method for a multi-branch distribution line.
Referring to fig. 2, fig. 2 is a flowchart illustrating a method for locating a lightning strike fault of a multi-branch distribution line according to an embodiment of the present invention.
The embodiment of the invention provides a multi-branch distribution line lightning stroke fault positioning method, which comprises the following steps:
step S1, lightning current waveform data collected by each distributed lightning current monitoring terminal are obtained, the lightning current amplitude attenuation law of the multi-branch distribution line and the lightning current polarity relation on the main line are analyzed according to the lightning current waveform data, and the lightning stroke interval is determined according to the obtained analysis result.
In one implementation, the determining the lightning stroke interval according to the obtained analysis result includes:
taking the interval of two adjacent monitoring points on the main line as a monitoring interval, and determining the interval type of each monitoring interval according to the number of branch lines connected with the main line section in the monitoring interval, wherein the interval types comprise an interval without connecting branch lines on the main line section, an interval with one branch line connected with the main line section and an interval with a plurality of branch lines connected with the main line section;
calculating the average value of the lightning current amplitude attenuation rate corresponding to each interval type according to the lightning current amplitude attenuation rule, calculating the difference value between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rate corresponding to the interval type, and taking the monitoring interval with the difference value larger than a preset threshold value as an alternative lightning stroke interval;
and determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line.
According to the attenuation rule of the lightning current amplitude on the multi-branch 10kV distribution line, the branch number of each section on the multi-branch line is different, the attenuation rate of the lightning current peak value on the section is different, and when lightning stroke occurs in the monitoring section, the attenuation rate of the lightning current peak value of the line is different between the near section and the far end of the monitoring section. For example, in each monitoring section of the main line, when a lightning current passes through a section of the main line section without the connected branch line, the peak attenuation is less than 20%, and when a lightning strike occurs in a section adjacent to the section of the main line section without the connected branch line, the lightning current amplitude attenuation in the section is 27.7%, the average attenuation rate of the line lightning current amplitude in the section of the main line section with the connected branch line is not more than 40%, and when a lightning strike occurs in the adjacent section, the lightning current peak attenuation rate in the section of the main line section with the connected branch line is 59.8%, the average attenuation rate of the current peak attenuation rate in the section of the main line section with the connected branch lines is not more than 80%, and when a lightning strike occurs in the adjacent section, the attenuation rate of the lightning current peak value in the section is 90%.
Based on the above rules, in this embodiment, the difference between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rates corresponding to the type of the interval to which the monitoring interval belongs is calculated, and the monitoring interval with the difference larger than the preset threshold is used as the alternative lightning stroke interval, so that the preliminary determination of the lightning stroke interval is realized. And then, determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line, so as to finally determine the lightning stroke interval. The lightning stroke interval is determined by combining the lightning current amplitude attenuation rule of the multi-branch distribution line and the lightning current polarity relation on the main line, so that the accuracy of lightning stroke interval identification can be effectively improved, and a good foundation is laid for accurate positioning of follow-up lightning stroke faults.
And determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line, specifically according to whether the polarities of the lightning currents on monitoring points at two ends of the alternative lightning stroke intervals are opposite. When the polarity of the lightning current is opposite, the alternative lightning stroke interval is indicated to contain a lightning stroke fault point, and the alternative lightning stroke interval is judged to be a lightning stroke interval at the moment; and when the lightning current polarities are consistent, the alternative lightning stroke interval does not contain a lightning stroke fault point, and the alternative lightning stroke interval is judged not to be a lightning stroke interval.
It should be noted that the polarity of the lightning current can be determined according to all existing methods, for example, the polarity of the first wave head of the transient current line mode component of the lightning stroke is usually taken as the polarity of the lightning current. The embodiment of the present invention is not limited thereto.
And S2, screening target monitoring points from all monitoring points in the lightning stroke interval according to the lightning current peak value acquired by the distributed lightning current monitoring terminals in the lightning stroke interval.
In an implementation manner, the screening out target monitoring points from monitoring points in the lightning stroke interval according to the magnitude of the lightning current peak value collected by the distributed lightning current monitoring terminal in the lightning stroke interval includes:
sequencing corresponding monitoring points according to the sequence of the lightning current peak values collected by the distributed lightning current monitoring terminals in the lightning stroke interval from large to small;
and selecting N monitoring points in the front of the sequence as target monitoring points, wherein N is less than N, and N is the number of the monitoring points in the lightning stroke interval.
And step S3, performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point, taking the time point of the occurrence of the wavelet transformation maximum value as the arrival time of lightning fault traveling waves, and calculating the distance from the lightning fault point to the corresponding target monitoring point.
As a specific embodiment, a formula for performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point is as follows:
Figure BDA0003688822540000081
in the formula, Wf (a, b) refers to a transform value when a frequency is a and time is b after wavelet transform is performed on a signal f (t), ψ (t) is a wavelet mother function, a is a scale factor (corresponding to frequency information), b is a shift factor (corresponding to spatio-temporal information), ψ * (t) is the complex conjugate of ψ (t).
As a specific implementation manner, the calculation formula of the distance from the lightning stroke fault point to the corresponding target monitoring point is as follows:
L c =vt δ
in the formula, L c The distance from a lightning stroke fault point to a corresponding target monitoring point, v is the propagation speed of a current wave along the line, t δ And the traveling wave arrival time of the lightning stroke fault.
In the simulation program, the propagation speed v of the current wave along the line is set as the light speed t δ Obtained from the time point when the modulo maximum in the wavelet transform occurs.
In the implementation, the time point of the maximum value of the wavelet transformation modulus is used as the time of the arrival of the wave head of the current traveling wave, the time of the wave head of the current traveling wave arriving at the target monitoring point is extracted, the distance between the lightning stroke fault point and the selected target monitoring point is calculated, and the accuracy of positioning the lightning stroke fault point can be improved.
And step S4, according to the distance between the lightning stroke fault point and the corresponding target monitoring point, determining a lightning stroke fault point set corresponding to each target monitoring point, solving the intersection of all the determined lightning stroke fault point sets, and taking the obtained intersection result as the lightning stroke fault point of the multi-branch distribution line.
Aiming at a certain target monitoring point in a multi-branch line of a distribution network, the time for lightning current traveling waves of a plurality of points with the same distance to reach the point is possibly the same, namely the traveling wave theory is adopted to judge a plurality of lightning fault points. For example, for the target monitoring point M1, the calculation result is finally a set including 3 lightning stroke fault points, for the target monitoring points N2 and N3, the calculation results are both sets including 2 lightning stroke fault points, and the intersection of the sets of lightning stroke fault points calculated by the three target monitoring points is taken as the final lightning stroke fault point, so that other false lightning stroke fault points are eliminated.
In one implementation, as shown in fig. 3, the method further includes:
and step S5, determining the lightning current waveform characteristics and the change rule of the multi-branch distribution line under the lightning strokes of different lightning stroke types through simulation analysis, and extracting the typical characteristics for identifying the lightning stroke types according to the lightning current waveform characteristics and the change rule.
Among them, the lightning strike types include induction lightning, direct lightning and counterlightning. When step S5 is executed, an induced lightning, direct lightning strike and counterattack lightning overvoltage simulation analysis model may be established based on the topological structure and parameters of the actual multi-branch distribution line, and the waveform characteristics and the variation rules of lightning current on the line under three types of lightning strikes, such as the amplitude and attenuation rules of lightning current, the wave front time and variation rules, the polarity and variation rules, the pulse width and variation rules, etc., are simulated and analyzed, and the typical characteristics of the lightning current waveform at each monitoring point are extracted as the basis for judging the three types of lightning strikes.
And step S6, extracting lightning current waveform characteristics corresponding to the lightning stroke interval, and comparing the extracted lightning current waveform characteristics with each typical characteristic to determine the type of the lightning stroke.
The typical characteristic extraction and the lightning current waveform characteristic extraction can be carried out according to the characteristics of different lightning stroke types. For example, for inductive mines, direct lightning and counterlightning, the characteristics include: when induction lightning occurs, the three-phase polarities of wave heads collected by adjacent distributed lightning current monitoring terminals are the same; when direct impact occurs, the polarity of the phase current of the lightning stroke phase is opposite to that of the phase current of the non-lightning stroke phase; when a counterattack occurs, the steepness of the wave head of the line current is greater due to the occurrence of a flashover. Therefore, the characteristic quantities such as the three-phase polarity and the gradient of the wave head can be extracted to be used as the judgment basis of the three lightning stroke types.
And step S7, if the determined lightning stroke type is induction lightning or direct lightning, judging whether the line on the lightning stroke interval has flashover or not, and outputting a corresponding line flashover judgment result.
When judging whether flashover occurs after lightning strike on the line, if the integral of the square of the current of the conducting wire monitored by the distributed lightning current monitoring terminal exceeds a threshold value, judging that the corresponding line does not flashover, otherwise, judging that the corresponding line has flashover; judging whether the lightning stroke type is an induction lightning or a direct lightning from the angles of lightning current polarity and three-phase balance degree, wherein when the induction lightning occurs, wave head three-phase polarities collected by adjacent distributed lightning current monitoring terminals are the same; when the direct-strike occurs, the polarity of the phase current of the lightning stroke phase is opposite to that of the phase current of the non-lightning stroke phase.
It should be noted that the line flashover determination may also be implemented based on an existing line flashover determination method. The embodiment of the present invention is not limited thereto.
The invention also provides a multi-branch distribution line lightning stroke fault positioning device.
Referring to fig. 4, fig. 4 is a block diagram illustrating a structural connection of a lightning strike fault location apparatus for a multi-branch distribution line according to an embodiment of the present invention.
The embodiment of the invention provides a multi-branch distribution line lightning stroke fault positioning device, which comprises:
the lightning stroke interval determining module 1 is used for acquiring lightning current waveform data acquired by each distributed lightning current monitoring terminal, analyzing the lightning current amplitude attenuation rule of a multi-branch distribution line and the lightning current polarity relation on a main line according to the lightning current waveform data, and determining a lightning stroke interval according to the obtained analysis result;
the target monitoring point screening module 2 is used for screening target monitoring points from all monitoring points in the lightning stroke interval according to the lightning current peak value acquired by the distributed lightning current monitoring terminals in the lightning stroke interval;
the lightning stroke fault point distance calculating module 3 is used for performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point, taking a time point of occurrence of a wavelet transformation maximum value as lightning stroke fault traveling wave arrival time, and calculating the distance from the lightning stroke fault point to the corresponding target monitoring point;
and the lightning stroke fault point positioning module 4 is used for determining a lightning stroke fault point set corresponding to each target monitoring point according to the distance from the lightning stroke fault point to the corresponding target monitoring point, solving the intersection of all the determined lightning stroke fault point sets, and taking the obtained intersection result as the lightning stroke fault point of the multi-branch distribution line.
In an implementable manner, the lightning stroke interval determination module 1 comprises:
the section classification unit is used for taking the section of two adjacent monitoring points on the main line as a monitoring section, and determining the section type of each monitoring section according to the number of branch lines connected with the main line section in the monitoring section, wherein the section types comprise the section of the main line section without connecting branch lines, the section of the main line section with one branch line and the section of the main line section with a plurality of branch lines;
the first interval determining unit is used for calculating the average value of the lightning current amplitude attenuation rate corresponding to each interval type according to the lightning current amplitude attenuation rule, calculating the difference value between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rate corresponding to the interval type, and taking the monitoring interval with the difference value larger than a preset threshold value as an alternative lightning stroke interval;
and the second interval determining unit is used for determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line.
In an implementation manner, the target monitoring point screening module 2 includes:
the monitoring point sorting unit is used for sorting the corresponding monitoring points according to the sequence of the lightning current peak values collected by the distributed lightning current monitoring terminals in the lightning stroke interval from large to small;
and the monitoring point screening unit is used for selecting N monitoring points before sorting as target monitoring points, wherein N is less than N, and N is the number of the monitoring points in the lightning stroke interval.
In one implementation, as shown in fig. 5, the apparatus further includes:
the simulation analysis module 5 is used for determining lightning current waveform characteristics and change rules of the multi-branch distribution line under lightning strokes of different lightning stroke types through simulation analysis, and extracting typical characteristics for identifying the lightning stroke types according to the lightning current waveform characteristics and the change rules;
the lightning type determining module 6 is configured to extract lightning current waveform characteristics corresponding to the lightning stroke interval, and compare the extracted lightning current waveform characteristics with each of the typical characteristics to determine a lightning type;
and the line flashover judging module 7 is used for judging whether a line on the lightning stroke interval has flashover or not when the determined lightning stroke type is induction lightning or direct lightning, and outputting a corresponding line flashover judging result.
The invention also provides a multi-branch distribution line lightning stroke fault positioning device, which comprises:
a memory to store instructions; wherein the instructions are used for implementing the multi-branch distribution line lightning strike fault location method according to any one of the above embodiments;
a processor to execute the instructions in the memory.
The invention further provides a computer-readable storage medium, wherein a computer program is stored on the computer-readable storage medium, and when being executed by a processor, the computer program realizes the multi-branch distribution line lightning stroke fault location method according to any one of the above embodiments.
The embodiment of the invention combines the lightning current amplitude attenuation rule of the multi-branch distribution line and the lightning current polarity relation on the main line to determine the lightning stroke interval, can improve the accuracy of determining the lightning stroke interval, screens the target monitoring points from all the monitoring points in the lightning stroke interval, lightning stroke fault point positioning is carried out according to the lightning stroke fault point set of the target monitoring point, efficiency is improved compared with the mode of carrying out the lightning stroke fault point positioning by the lightning stroke fault point set of all monitoring points in a lightning stroke interval, and finally false lightning stroke fault points are checked by the mode of solving intersection of all the determined lightning stroke fault point sets, so that the lightning stroke fault point positioning precision is further improved, therefore, the lightning stroke fault of the multi-branch distribution line can be quickly and accurately positioned and identified, and a foundation is provided for quickly checking the fault of the multi-branch 10kV power distribution network and quickly recovering power supply.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described apparatuses and modules may refer to the corresponding processes in the foregoing method embodiments, and the specific beneficial effects of the above-described apparatuses and modules may refer to the corresponding beneficial effects in the foregoing method embodiments, which are not described herein again.
In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the modules is only one logical functional division, and other divisions may be realized in practice, for example, a plurality of modules or components may be combined or integrated into another system, or some features may be omitted, or not executed.
The modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical modules, may be located in one place, or may be distributed on a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.
In addition, functional modules in the embodiments of the present invention may be integrated into one processing module, or each of the modules may exist alone physically, or two or more modules are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode.
The integrated module, if implemented in the form of a software functional module and sold or used as a separate product, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
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; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims (10)

1. A multi-branch distribution line lightning stroke fault positioning method is characterized in that a plurality of monitoring points are arranged on a main line of a multi-branch distribution line at intervals, one monitoring point is arranged on a branch line, and each monitoring point is provided with a distributed lightning current monitoring terminal, and the method comprises the following steps:
acquiring lightning current waveform data acquired by each distributed lightning current monitoring terminal, analyzing a lightning current amplitude attenuation rule of a multi-branch distribution line and a lightning current polarity relation on a main line according to the lightning current waveform data, and determining a lightning stroke interval according to an obtained analysis result;
screening target monitoring points from all monitoring points in the lightning stroke interval according to the magnitude of lightning current peak values collected by distributed lightning current monitoring terminals in the lightning stroke interval;
performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point, taking the time point of occurrence of a wavelet transformation maximum value as the arrival time of lightning fault traveling waves, and calculating the distance from the lightning fault point to the corresponding target monitoring point;
and determining a lightning stroke fault point set corresponding to each target monitoring point according to the distance from the lightning stroke fault point to the corresponding target monitoring point, solving the intersection of all the determined lightning stroke fault point sets, and taking the obtained intersection result as the lightning stroke fault point of the multi-branch distribution line.
2. The method of claim 1, wherein determining the lightning strike interval according to the analysis result comprises:
taking the interval of two adjacent monitoring points on the main line as a monitoring interval, and determining the interval type of each monitoring interval according to the number of branch lines connected with the main line section in the monitoring interval, wherein the interval types comprise an interval without connecting branch lines on the main line section, an interval with one branch line connected with the main line section and an interval with a plurality of branch lines connected with the main line section;
calculating the average value of the lightning current amplitude attenuation rate corresponding to each interval type according to the lightning current amplitude attenuation rule, calculating the difference value between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rate corresponding to the interval type, and taking the monitoring interval with the difference value larger than a preset threshold value as an alternative lightning stroke interval;
and determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line.
3. The method for locating the lightning stroke fault of the multi-branch distribution line according to claim 1, wherein the step of screening target monitoring points from monitoring points in the lightning stroke interval according to the magnitude of the lightning current peak value collected by the distributed lightning current monitoring terminal in the lightning stroke interval comprises the following steps:
sequencing corresponding monitoring points according to the sequence of the lightning current peak values collected by the distributed lightning current monitoring terminals in the lightning stroke interval from large to small;
and selecting N monitoring points in the front of the sequence as target monitoring points, wherein N is less than N, and N is the number of the monitoring points in the lightning stroke interval.
4. The method of claim 1, further comprising:
determining lightning current waveform characteristics and change rules of the multi-branch distribution line under lightning strokes of different lightning stroke types through simulation analysis, and extracting typical characteristics for identifying the lightning stroke types according to the lightning current waveform characteristics and the change rules;
lightning current waveform characteristics corresponding to the lightning stroke interval are extracted, and the extracted lightning current waveform characteristics are compared with each typical characteristic to determine the type of lightning stroke;
and if the determined lightning stroke type is induction lightning or direct lightning, judging whether the line on the lightning stroke interval has flashover or not, and outputting a corresponding line flashover judgment result.
5. The utility model provides a multi-branch distribution lines thunderbolt fault positioner, a plurality of monitoring points of interval arrangement on the main line of multi-branch distribution lines, arrange a monitoring point on the branch line, every set up distributed lightning current monitor terminal on the monitoring point, its characterized in that, the device includes:
the lightning stroke interval determining module is used for acquiring lightning current waveform data acquired by each distributed lightning current monitoring terminal, analyzing the lightning current amplitude attenuation rule of the multi-branch distribution line and the lightning current polarity relation on the main line according to the lightning current waveform data, and determining a lightning stroke interval according to the obtained analysis result;
the target monitoring point screening module is used for screening target monitoring points from all monitoring points in the lightning stroke interval according to the lightning current peak value acquired by the distributed lightning current monitoring terminals in the lightning stroke interval;
the lightning stroke fault point distance calculation module is used for performing wavelet transformation on lightning current waveform data corresponding to each target monitoring point, taking a time point of occurrence of a wavelet transformation maximum value as the arrival time of a lightning stroke fault traveling wave, and calculating the distance from the lightning stroke fault point to the corresponding target monitoring point;
and the lightning stroke fault point positioning module is used for determining a lightning stroke fault point set corresponding to each target monitoring point according to the distance from the lightning stroke fault point to the corresponding target monitoring point, solving the intersection of all the determined lightning stroke fault point sets, and taking the obtained intersection result as the lightning stroke fault point of the multi-branch distribution line.
6. The multi-branch distribution line lightning strike fault location device of claim 5, wherein the lightning strike interval determination module comprises:
the section classification unit is used for taking the section of two adjacent monitoring points on the main line as a monitoring section, and determining the section type of each monitoring section according to the number of branch lines connected with the main line section in the monitoring section, wherein the section types comprise the section of the main line section without connecting branch lines, the section of the main line section with one branch line and the section of the main line section with a plurality of branch lines;
the first interval determining unit is used for calculating the average value of the lightning current amplitude attenuation rate corresponding to each interval type according to the lightning current amplitude attenuation rule, calculating the difference value between the lightning current amplitude attenuation rate corresponding to each monitoring interval and the average value of the lightning current amplitude attenuation rate corresponding to the interval type, and taking the monitoring interval with the difference value larger than a preset threshold value as an alternative lightning stroke interval;
and the second interval determining unit is used for determining a lightning stroke interval from each alternative lightning stroke interval according to the polarity relation of the lightning current on the main line.
7. The multi-branch distribution line lightning strike fault location device of claim 5, wherein the target monitoring point screening module comprises:
the monitoring point sorting unit is used for sorting the corresponding monitoring points according to the sequence of the lightning current peak values collected by the distributed lightning current monitoring terminals in the lightning stroke interval from large to small;
and the monitoring point screening unit is used for selecting N monitoring points before sorting as target monitoring points, wherein N is less than N, and N is the number of the monitoring points in the lightning stroke interval.
8. The multi-branch distribution line lightning strike fault location device of claim 5, further comprising:
the simulation analysis module is used for determining lightning current waveform characteristics and change rules of the multi-branch distribution line under lightning strokes of different lightning stroke types through simulation analysis, and extracting typical characteristics for identifying the lightning stroke types according to the lightning current waveform characteristics and the change rules;
the lightning type determining module is used for extracting lightning current waveform characteristics corresponding to the lightning stroke interval and comparing the extracted lightning current waveform characteristics with each typical characteristic to determine the lightning stroke type;
and the line flashover judging module is used for judging whether the line on the lightning stroke interval has flashover or not and outputting a corresponding line flashover judging result when the determined lightning stroke type is induction lightning or direct lightning.
9. The utility model provides a multi-branch distribution lines thunderbolt fault positioner which characterized in that includes:
a memory to store instructions; wherein the instructions are for implementing the multi-branch distribution line lightning strike fault location method of any one of claims 1-4;
a processor to execute the instructions in the memory.
10. A computer-readable storage medium, having a computer program stored thereon, which, when executed by a processor, implements the method of multi-branch distribution line lightning strike fault location according to any one of claims 1-4.
CN202210654586.8A 2022-06-10 2022-06-10 Multi-branch distribution line lightning stroke fault positioning method and device and storage medium Pending CN114878973A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115616349A (en) * 2022-11-30 2023-01-17 昆明理工大学 Multi-lightning-stroke identification method and system based on multi-metadata fusion

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115616349A (en) * 2022-11-30 2023-01-17 昆明理工大学 Multi-lightning-stroke identification method and system based on multi-metadata fusion
CN115616349B (en) * 2022-11-30 2023-03-14 昆明理工大学 Multi-lightning stroke recognition method and system based on multi-metadata fusion

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