Fault positioning method and device, electronic equipment, storage medium and program product

Abstract

The invention discloses a fault positioning method and device, electronic equipment, a storage medium and a program product. The method comprises the steps that when it is detected that a traveling wave analysis starting condition is met, a to-be-analyzed fault traveling wave signal set of two measuring points of a line is obtained, the fault traveling wave signal set comprises fault traveling wave signals collected in different sampling periods, and the traveling wave analysis starting condition is determined according to a gain function of a power frequency signal; for each fault traveling wave signal set, constructing a stochastic resonance system potential function according to the fault traveling wave signal set, and performing system resonance on the fault traveling wave signal according to the stochastic resonance system potential function to obtain a traveling wave signal to be extracted; performing wave head extraction on the traveling wave signal to be extracted, and recording the traveling wave arrival time corresponding to the measuring point; and fault positioning is carried out according to the traveling wave arrival time corresponding to each measuring point and the total length of the line, the fault position is determined, and the problems of inaccurate fault traveling wave signal acquisition and inaccurate wave head extraction are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid fault detection, and in particular to a fault location method, device, electronic equipment, storage medium and program product. Background Art

[0002] As the complexity of power grids and the transmission capacity of lines increase, the impact and losses caused by line failures are increasing, and the requirements for fault distance measurement accuracy are also increasing. The impedance method principle used by traditional distance measurement devices is difficult to overcome the influence of factors such as transition resistance, system operation mode, line distributed capacitance, transmission error and current transformer saturation, and the distance measurement accuracy is generally not high. In contrast, the traveling wave principle is not affected by the above factors, and therefore has attracted widespread attention from scholars at home and abroad.

[0003] Traveling wave ranging technology uses the characteristics of traveling waves propagating in transmission lines to determine the location of the fault point by analyzing the changes in the voltage waveform. Most traveling wave ranging devices use the size of the mutation as the recording start condition, but the fault traveling wave waveform is not only related to the fault type, fault location, and fault starting angle, but also affected by line noise, mutual refraction of adjacent lines, and electromagnetic coupling of multiple conductors. It is difficult to accurately define the fault start threshold. Therefore, judging whether the recording is started by the fault start threshold is of low accuracy and cannot accurately collect the fault traveling wave signal. After the traveling wave is started, due to the influence of transition resistance, fault distance, and signal frequency on the wave head, the wave head energy changes greatly, especially when the signal frequency is too high, the amplitude of the traveling wave head is too low, or the traveling wave cannot be accurately detected, resulting in the problem of ranging failure, which has not been effectively solved. Summary of the invention

[0004] The present invention provides a fault location method, device, electronic equipment, storage medium and program product to solve the problems of inaccurate acquisition of fault traveling wave signals and inaccurate wave head extraction.

[0005] According to one aspect of the present invention, a fault location method is provided, comprising:

[0006] When it is detected that the traveling wave analysis start condition is met, a set of fault traveling wave signals to be analyzed of two measuring points of the line is obtained, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to a gain function of the power frequency signal;

[0007] For each set of fault traveling wave signals, a stochastic resonance system potential function is constructed according to the set of fault traveling wave signals, and a system resonance is performed on the fault traveling wave signals according to the stochastic resonance system potential function to obtain traveling wave signals to be extracted; a wave head is extracted from the traveling wave signals to be extracted, and the arrival time of the traveling wave corresponding to the measuring point is recorded;

[0008] The fault location is performed according to the arrival time of the traveling wave corresponding to each measuring point and the total length of the line to determine the fault position.

[0009] According to another aspect of the present invention, there is provided a fault location device, comprising:

[0010] A fault traveling wave acquisition module is used to acquire a set of fault traveling wave signals to be analyzed of two measuring points of the line when it is detected that the traveling wave analysis start condition is met, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to the gain function of the power frequency signal;

[0011] A wave head extraction module is used to construct a stochastic resonance system potential function according to each set of fault traveling wave signals, perform system resonance on the fault traveling wave signals according to the stochastic resonance system potential function, and obtain traveling wave signals to be extracted; perform wave head extraction on the traveling wave signals to be extracted, and record the arrival time of the traveling wave corresponding to the measuring point;

[0012] The fault location module is used to locate the fault according to the arrival time of the traveling wave corresponding to each measuring point and the total length of the line to determine the fault position.

[0013] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0014] at least one processor, and a memory communicatively coupled to the at least one processor;

[0015] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the fault location method described in any embodiment of the present invention.

[0016] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the fault location method described in any embodiment of the present invention when executed.

[0017] According to another aspect of the present invention, a computer program product is provided. The computer program product includes a computer program. When the computer program is executed by a processor, the fault location method according to any embodiment of the present invention is implemented.

[0018] The technical solution of the embodiment of the present invention is as follows: when it is detected that the traveling wave analysis start condition is met, a set of fault traveling wave signals to be analyzed of two measuring points of the line is obtained, the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to the gain function of the power frequency signal; for each set of fault traveling wave signals, a random resonance system potential function is constructed according to the set of fault traveling wave signals, and a system resonance is performed on the fault traveling wave signal according to the random resonance system potential function to obtain a traveling wave signal to be extracted; a wave head is extracted for the traveling wave signal to be extracted, and the arrival time of the traveling wave corresponding to the measuring point is recorded; and according to the corresponding The fault is located by the arrival time of the traveling wave and the total length of the line, and the fault position is determined, which solves the problems of inaccurate acquisition of fault traveling wave signals and inaccurate wave head extraction. The starting conditions of traveling wave analysis are determined by the gain function of the power frequency signal to ensure the accurate start timing of traveling wave analysis, avoid untimely or inaccurate fault analysis caused by untimely recording start, and improve the accuracy of wave head start detection; by constructing a random resonance system potential function, the fault traveling wave signal is subjected to system resonance to obtain the traveling wave signal to be extracted, and the wave head of the traveling wave signal to be extracted is extracted to improve the accuracy of wave head recognition; the fault is accurately located according to the wave head arrival time.

[0019] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 is a flowchart of a fault location method provided according to Embodiment 1 of the present invention;

[0022] Figure 2 is a flowchart of a fault location method provided according to Embodiment 2 of the present invention;

[0023] Figure 3 is an example diagram of implementing a system resonance according to the second embodiment of the present invention;

[0024] Figure 4 is an example diagram of a traveling wave arrival time provided according to Embodiment 2 of the present invention;

[0025] Figure 5is an example diagram of implementing a fault location according to the second embodiment of the present invention;

[0026] Figure 6 is a structural schematic diagram of a fault location device provided according to Embodiment 3 of the present invention;

[0027] Figure 7 It is a structural schematic diagram of an electronic device for implementing the fault location method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] Embodiment 1

[0031] Figure 1 This is a flow chart of a fault location method provided in the first embodiment of the present invention. This embodiment is applicable to the situation of accurately locating faults in the distribution network. The method can be executed by a fault location device. The fault location device can be implemented in the form of hardware and / or software. The fault location device can be configured in an electronic device. Figure 1 As shown, the method includes:

[0032] S101. When it is detected that a traveling wave analysis start condition is met, a set of fault traveling wave signals to be analyzed of two measuring points of the line is obtained, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to a gain function of the power frequency signal.

[0033] In this embodiment, the traveling wave analysis start condition can be understood as a condition for determining whether to start recording to perform fault analysis on the traveling wave. The fault traveling wave signal set can be understood as a data set storing fault traveling wave signals. The fault traveling wave signal set includes fault traveling wave signals collected at different sampling periods, that is, the fault traveling wave signal is a periodic signal. When locating the fault, the embodiment of the present application needs to collect multiple fault traveling wave signals of different periods for fault analysis. The power frequency signal refers to signals such as voltage or current transmitted in the distribution network.

[0034] Detect the power frequency signal in the distribution network in real time or according to certain requirements or rules, pre-set the starting conditions for traveling wave analysis, analyze the power frequency signal, and determine whether the starting conditions for traveling wave analysis are met. The starting conditions for traveling wave analysis in the embodiment of the present application are determined according to the gain function of the power frequency signal. The expression of the gain function can be pre-defined, the power frequency signal is collected and substituted into the expression, the gain function of the power frequency signal is calculated based on the expression, and whether the starting conditions for traveling wave analysis are met is determined according to the gain function. Exemplarily, the gain function can be calculated based on the waveform energy integral of the power frequency signal, that is, the starting conditions for traveling wave analysis are determined according to the waveform energy integral of the power frequency signal.

[0035] Traveling wave ranging devices are set at the measuring points on both sides of the distribution network, and the fault traveling wave signals are collected by the traveling wave ranging devices. The measuring points on both sides of the distribution network are at both ends of a line to locate the fault point at any position in the line. When a fault occurs in the distribution network, a fault traveling wave signal will be generated at the same time. The embodiment of the present application will also detect the fault traveling wave signal while collecting the power frequency signal. When it is detected that the starting conditions for traveling wave analysis are met, the recording is started, and the fault traveling wave signals to be analyzed collected at the two measuring points of the line are obtained, and the fault traveling wave signals within a period of time are obtained. They are used as a set of fault traveling wave signals and subsequent fault analysis and positioning are performed. For example, after it is detected that the starting conditions for traveling wave analysis are met, this time is recorded as t1. Since the propagation of the fault requires a certain amount of time, in order to ensure the accurate collection of the fault traveling wave signal and avoid missing data, the fault traveling wave signal within a period of time before and after t1 is obtained to form a set of fault traveling wave signals. For example, the fault traveling wave signal in the time period from t1-T to t1+T is obtained, and T is the period of the power frequency signal. When the conditions for starting the traveling wave analysis are not met, there is no need to start the recording, nor is there any need to analyze the fault traveling wave signal.

[0036] S102, for each set of fault traveling wave signals, construct a stochastic resonance system potential function according to the set of fault traveling wave signals, perform system resonance on the fault traveling wave signals according to the stochastic resonance system potential function, and obtain traveling wave signals to be extracted; perform wave head extraction on the traveling wave signals to be extracted, and record the arrival time of the traveling wave corresponding to the measuring point.

[0037] In this embodiment, the potential function of the random resonance system can be understood as a system for processing signals, and this system is a random resonance system, which is a nonlinear system; the potential function of the random resonance system in the embodiment of the present application is the potential function of this nonlinear system. The traveling wave signal to be extracted can be understood as the fault traveling wave signal whose wave head needs to be extracted. The traveling wave arrival time can be the wave head time when the traveling wave signal first arrives at the measuring point, the time when it arrives at the measuring point after reflection, the time when it arrives at the measuring point after refraction, and so on.

[0038] Since each measuring point collects a set of fault traveling wave signals, each set of fault traveling wave signals is processed to obtain the arrival time of the traveling wave corresponding to this measuring point. For each set of fault traveling wave signals, the fault traveling wave signals in the fault traveling wave signal set are analyzed, and the relationship between the fault traveling wave signals of different sampling periods is constructed according to the parameters of the random resonance system potential function. The parameters of the random resonance system potential function are obtained based on the fault traveling wave signals of different sampling periods and the relationship between the signals. The random resonance system potential function is constructed based on the parameters of the random resonance system potential function. According to the random resonance system potential function, each fault traveling wave signal is subjected to system resonance, that is, the fault traveling wave signal is used as the input of the random resonance system, and is processed by the random resonance system to obtain the traveling wave signal to be extracted. The process of the random resonance system processing the fault traveling wave signal is as follows: the fault traveling wave signal is subjected to system resonance by the random resonance system potential function, the noise signal in the fault traveling wave signal is filtered, and the effective signal is amplified for subsequent wave head extraction, and the traveling wave signal to be extracted is obtained after system resonance. Analyze the traveling wave signal to be extracted, analyze the amplitude of the waveform of the traveling wave signal to be extracted, analyze the size and change of the amplitude, extract the wave head according to the analysis results, determine the arrival time of the traveling wave corresponding to the measuring point and record it.

[0039] The propagation characteristics of voltage signals in transmission lines are relatively stable and are less affected by external interference. However, the voltage traveling wave is severely attenuated by electromagnetic transformers, so the current traveling wave distance measurement and protection devices also use current traveling waves for calculation. At present, the main methods for determining the wave head are wavelet transform, S transform, Hilbert transform, etc. Wavelet transform is easily affected by the decomposition scale and type, while the resolution of S transform is easily affected by frequency, so both methods have certain limitations in practical applications. At the same time, there are multiple impedance discontinuities in the line, and the traveling wave will undergo multiple refractions and reflections during the propagation process, which makes it difficult to identify the wave head of the traveling wave.

[0040] The embodiment of the present application accurately collects the fault traveling wave signal by optimizing the timing of starting the recording, and obtains the traveling wave signal to be extracted by performing system resonance on the fault traveling wave signal by constructing a random resonance system potential function. Since the traveling wave signal to be extracted is subjected to noise filtering and effective signal amplification, the result is more accurate when extracting the wave head.

[0041] It should be noted that the fault traveling wave signals, traveling wave signals to be extracted, power frequency signals and other signals in the embodiments of the present application refer to continuous signals within a period of time, and their time lengths may be different; when processing each signal, the embodiments of the present application may process a segment of the signal, and a segment of the signal may form a certain waveform.

[0042] S103: perform fault location according to the arrival time of the traveling wave corresponding to each measuring point and the total length of the line to determine the fault position.

[0043] In this embodiment, the fault location is used to describe the location of the fault point where the fault occurs, which may be the distance between the fault point and the measuring point. The total line length may be understood as the total length of the line of the distribution network, which may be the distance between two measuring points.

[0044] According to the arrival time of the traveling wave corresponding to the measuring point and the total length of the line, the distance between the fault point and the measuring point is calculated according to the kinematic formula, and then the fault position is determined to locate the fault. In the embodiment of the present application, the kinematic calculation formula can be determined in advance, and the arrival time of the traveling wave and the total length of the line are substituted into the formula for calculation to obtain the distance between the fault point and the measuring point.

[0045] The fault location method provided by the embodiment of the present invention solves the problems of inaccurate acquisition of fault traveling wave signals and inaccurate wave head extraction. The traveling wave analysis start condition is determined by the gain function of the power frequency signal, so as to ensure the accurate start timing of the traveling wave analysis, avoid untimely or inaccurate fault analysis caused by untimely recording start, and improve the accuracy of wave head start detection; by constructing a random resonance system potential function to perform system resonance on the fault traveling wave signal, the traveling wave signal to be extracted is obtained, and the wave head of the traveling wave signal to be extracted is extracted to improve the accuracy of wave head recognition; the fault is accurately located according to the wave head arrival time, so as to improve the accuracy of fault location and achieve precise positioning.

[0046] Embodiment 2

[0047] Figure 2 This is a flow chart of a fault location method provided in Embodiment 2 of the present invention. This embodiment is refined on the basis of the above embodiment. Figure 2 As shown, the method includes:

[0048] S201. Acquire a first power frequency signal and a second power frequency signal.

[0049] In this embodiment, the first power frequency signal and the second power frequency signal can be understood as a power frequency signal, and the time lengths corresponding to the first power frequency signal and the second power frequency signal are usually the same. For example, the first power frequency signal is a power frequency signal in the time period from t2 to t3, and the first power frequency signal is a power frequency signal in the time period from t4 to t5, where t3-t2=t5-t4. The power frequency signal is generated during the operation of the distribution network. The embodiment of the present application can collect the power frequency signal in the embodiment, or collect the power frequency signal under certain conditions to obtain the first power frequency signal and the second power frequency signal.

[0050] Optionally, the first power frequency signal and the second power frequency signal are collected in two different collection cycles, and an initial collection point of the first power frequency signal differs from an initial collection point of the second power frequency signal by one collection cycle.

[0051] The first power frequency signal and the second power frequency signal are collected in two different collection cycles, for example, the first power frequency signal and the second power frequency signal are collected in two adjacent collection cycles respectively; the initial collection point of the first power frequency signal differs from the initial collection point of the second power frequency signal by one collection cycle, for example, the initial collection point of the first power frequency signal is t2, and the initial collection point of the second power frequency signal is t2+T, where T is the period of the power frequency signal. The first power frequency signal and the second power frequency signal are collected in two different collection cycles, and if the two collection cycles may be adjacent or not adjacent, the initial collection point of the first power frequency signal differs from the initial collection point of the second power frequency signal by an integer multiple of the collection cycle.

[0052] S202, performing waveform energy integration on the first power frequency signal to obtain first signal energy, and performing waveform energy integration on the second power frequency signal to obtain second signal energy.

[0053] In this embodiment, the first signal energy and the second signal energy can be understood as the energy of the power frequency signal. The first signal energy is obtained by integrating the energy of the first power frequency signal waveform; the second signal energy is obtained by integrating the energy of the second power frequency signal waveform.

[0054] S203: Calculate a gain function according to the first signal energy and the second signal energy.

[0055] The calculation method of the gain function is predefined, for example, the ratio of the first signal energy to the second signal energy is used as the gain function, or the product of the first signal energy and the second signal energy is used as the gain function, etc. The calculation formula of the gain function can be predetermined, and the first signal energy and the second signal energy are substituted into the calculation formula for calculation to obtain the gain function.

[0056] As an optional embodiment of the present invention, the optional embodiment further calculates a gain function based on the first signal energy and the second signal energy, and optimizes the calculation as follows: calculating the difference between the second signal energy and the first signal energy to obtain an energy difference; calculating the sum of the second signal energy and the first signal energy to obtain an energy sum; and using the ratio of the energy difference to the energy sum as the gain function.

[0057] When the second power frequency signal is collected before the first power frequency signal, the energy of the first signal is subtracted from the energy of the second signal, and the difference is used as the energy difference; when the first power frequency signal is collected before the second power frequency signal, the energy of the second signal is subtracted from the energy of the first signal, and the difference is used as the energy difference; the energy of the second signal is added to the energy of the first signal to obtain the energy sum; the ratio of the energy difference to the energy sum is used as the gain function.

[0058] S204: When the gain function is greater than or equal to a predetermined gain function threshold, it is determined that a traveling wave analysis start condition is met.

[0059] In this embodiment, the gain function threshold can be understood as a preset threshold, and the gain function threshold can be set by analyzing historical data. The gain function is compared with the gain function threshold, and when the gain function is greater than or equal to the gain function threshold, it is determined that the traveling wave analysis start condition is met.

[0060] Exemplarily, the embodiment of the present application provides a method for calculating a gain function, by integrating the square of the amplitude of the waveform signal on the time axis to obtain the energy of the signal. At the same time, the energy function of the current time period is compared with the energy function of the previous period, and whether to start the recording is determined based on the gain function. High-frequency recording sampling generates a large amount of data, and the gain function of the power frequency signal is used to determine whether to start the storage analysis of the traveling wave recording, thereby reducing the analysis and calculation pressure of the ranging device and improving the accuracy.

[0061] The waveform energy function is constructed as:

[0062]

[0063] Among them, N t Represents the power frequency signal waveform energy function in the current period of time, and constructs the energy sum in any time period by integration, so as to improve the comparison accuracy. Preferably, t2-t1≥T / 4, A and A' are the amplitudes of the power frequency signal, and ω and ω' are the angular velocities. N t-T is the signal energy of the previous cycle corresponding to time t; illustratively, the first signal energy is N t , the second signal energy is N t-T . Z t is the gain function. By comparing the energy of the two time periods before and after, it is determined whether the signal has a mutation. 阈值Set to 0.6-0.8, when the gain function Z t Greater than the gain function threshold Z 阈值 Start the high-frequency recording analysis and calculation program to store the fault traveling wave signal x(t) for wave head extraction and analysis.

[0064] S205 . Obtain a set of fault traveling wave signals to be analyzed at two measuring points of the line, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods.

[0065] S206. For each fault traveling wave signal set, determine a first structural parameter and a second structural parameter based on the fault traveling wave signal set.

[0066] In this embodiment, the first structural parameter and the second structural parameter are two parameters of the potential function of the random resonance system. An expression of the potential function of the random resonance system is pre-constructed, and the expression includes at least two unknown parameters, the first structural parameter and the second result parameter. By analyzing the fault traveling wave signal in the fault traveling wave signal set, a relationship expression between the first structural parameter and the second structural parameter is constructed, and the fault traveling wave signal is substituted into the relationship expression for calculation to obtain the first structural parameter and the second structural parameter.

[0067] S207 , constructing a stochastic resonance system potential function according to the first structural parameter and the second structural parameter.

[0068] Substituting the first structural parameter and the second structural parameter into the expression of the stochastic resonance system potential function, the stochastic resonance system potential function is obtained, and the construction of the stochastic resonance system potential function is completed.

[0069] Exemplarily, the expression of the stochastic resonance system potential function U(y) is as follows:

[0070]

[0071] Wherein, a is the first structural parameter, b is the second structural parameter, and y is the output signal of the potential function of the stochastic resonance system.

[0072] As an optional embodiment of the present invention, the optional embodiment further determines the first structural parameter and the second structural parameter based on the fault traveling wave signal set, and optimizes them as follows:

[0073] A1. Obtain a first fault traveling wave signal, a second fault traveling wave signal, a third fault traveling wave signal and a fourth fault traveling wave signal from a fault traveling wave signal set, wherein the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are fault traveling wave signals collected in different adjacent sampling periods.

[0074] In this embodiment, the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal can be understood as fault traveling wave signals collected at different times; the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are fault traveling wave signals collected in different adjacent sampling periods.

[0075] By analyzing the acquisition time of the fault traveling wave signals in the fault traveling wave signal set, a first fault traveling wave signal, a second fault traveling wave signal, a third fault traveling wave signal and a fourth fault traveling wave signal are determined.

[0076] A2. Construct a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solve the traveling wave signal relationship function to obtain a first structural parameter and a second structural parameter.

[0077] In this embodiment, the traveling wave signal relationship function can be understood as a function expression that represents the relationship between traveling wave signals at different times. The relationship between fault traveling wave signals at different times is preset, and the relationship between fault traveling wave signals is represented by unknown parameters. The first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are substituted into the relationship to construct a traveling wave signal relationship function. The first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are known parameters. The unknown parameters in the traveling wave signal relationship function are solved according to the known parameters to obtain the first structural parameter and the second structural parameter.

[0078] Among them, the expression of the traveling wave signal relationship function is:

[0079]

[0080] Among them, x(t) is the first fault traveling wave signal, x(t+Δt) is the second fault traveling wave signal, x(t+2Δt) is the third fault traveling wave signal, and x(t+3Δt) is the fourth fault traveling wave signal; a is the first structural parameter, b is the second structural parameter; s(t) is the effective fault traveling wave signal, z(t) is the noise signal, k1 is the slope at the beginning of the time period, k2 and k3 are the slopes at the midpoint of the time period, k4 is the slope at the end of the time period, and △t is the sampling period of the fault traveling wave signal.

[0081] In the above expression, k1 is the slope at the beginning of the time period; k2 is the slope at the midpoint of the time period, and the slope k1 is used to represent the value of the middle section; k3 is also the slope of the midpoint, and is represented by k2; k4 is the slope at the end of the time period, and is represented by k3. When the four slopes are averaged, the slope is more representative. By iterating the sampled x(t), a and b are obtained, and the U(y) function is constructed. t takes values ​​between (t1-T) and (t1+T), and △t is much smaller than T.

[0082] Optionally, after determining the first structural parameter and the second structural parameter based on the fault traveling wave signal set, the method also includes: judging whether the first structural parameter and the second structural parameter meet the stability condition; if not, re-obtaining a new first fault traveling wave signal, a second fault traveling wave signal, a third fault traveling wave signal and a fourth fault traveling wave signal from the fault traveling wave signal set, and returning to execute constructing a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solving the traveling wave signal relationship function to obtain the first structural parameter and the second structural parameter, until the first structural parameter and the second structural parameter meet the stability condition.

[0083] In this embodiment, the stability condition can be understood as a condition for judging whether the structural parameters meet the requirements, for example, the stability condition is that the change values ​​of the first structural parameter and the second structural parameter of a continuous preset number are all within the set range, or the stability condition is that the first structural parameter and the second structural parameter are both within the set range, etc. The stability condition is set in advance to judge whether the first structural parameter and the second structural parameter meet the stability condition. If they meet, the potential function of the random resonance system is directly constructed according to the first structural parameter and the second structural parameter; if they do not meet, a new first fault traveling wave signal, a new second fault traveling wave signal, a new third fault traveling wave signal and a new fourth fault traveling wave signal are obtained from the fault traveling wave signal set, the traveling wave signal relationship function is reconstructed, and the new first structural parameter and the new second structural parameter are obtained by solving, and the new first structural parameter and the new second structural parameter are continuously judged whether the new first structural parameter and the new second structural parameter meet the stability condition. If they do not meet, the new fault traveling wave signal is continuously obtained to determine the new first structural parameter and the second structural parameter until the stability condition is met. For example, the first structural parameter and the second structural parameter determined for the first time do not meet the stability condition, and the newly acquired first fault traveling wave signal to the fourth fault traveling wave signal are x(t+4Δt), x(t+5Δt), x(t+6Δt) and x(t+7Δt), respectively.

[0084] Optionally, the fault traveling wave signal set includes fault traveling wave signals collected in at least four sampling periods, and at least one set of first structural parameters and second structural parameters is calculated by using the fault traveling wave signals in the four sampling periods.

[0085] S208 , performing system resonance on the fault traveling wave signal according to the stochastic resonance system potential function to obtain the traveling wave signal to be extracted; performing wave head extraction on the traveling wave signal to be extracted, and recording the arrival time of the traveling wave corresponding to the measuring point.

[0086] As an optional embodiment, this optional embodiment further performs system resonance on the fault traveling wave signal according to the random resonance system potential function to obtain the traveling wave signal to be extracted, and is optimized as follows: the fault traveling wave signal is cooperatively resonated through the random resonance system potential function, the effective signal in the fault traveling wave signal is amplified, and the traveling wave signal to be extracted is obtained.

[0087] The fault traveling wave signal is cooperatively resonated through the potential function of the random resonance system, the effective signal in the fault traveling wave signal is amplified through the cooperative resonance, the noise signal is filtered out, and the traveling wave signal to be extracted is obtained.

[0088] For example, Figure 3 A system resonance implementation example diagram is provided. As shown in the figure, the fault traveling wave signal is used as the input signal x(t), and x(t) is a high-frequency sampling input signal, which includes the effective fault traveling wave signal s(t) and the noise signal z(t), that is, x(t)=s(t)+z(t); the stochastic resonance system output signal is y(t), and y(t) is the amplified effective signal obtained after the system resonance, while the noise signal is eliminated. Among them, the stochastic resonance system is a monostable stochastic resonance system.

[0089] The output signal model consists of a nonlinear system, an effective signal, and a noise signal. The potential function is constructed based on a fourth-order precision single-step algorithm, and U(y) is the potential function of the stochastic resonance system. Therefore, after constructing U(y), the inverse and amplitude of the amplified output signal can be obtained, corresponding to the arrival time T of the traveling wave head.

[0090] Exemplarily, the embodiment of the present application provides a formula for calculating the traveling wave signal y(t) to be extracted:

[0091]

[0092] Among them, a and b are the first and second structural parameters of the monostable stochastic resonance system, and the value ranges of a and b are both greater than zero. When the noisy fault voltage traveling wave signal is input into the monostable stochastic resonance model, when the nonlinear system reaches a resonant synergistic relationship with s(t), the output signal reaches the maximum, achieving the purpose of extracting and denoising the fault traveling wave signal.

[0093] Substitute the potential function of the stochastic resonance system and the fault traveling wave signal into the system resonance formula for calculation to obtain the traveling wave signal to be extracted;

[0094] Among them, the expression of the system resonance formula is as follows:

[0095]

[0096] Among them, y(t) is the traveling wave signal to be extracted at time t, U(y) is the potential function of the stochastic resonance system, x(t) is the fault traveling wave signal at time t, a is the first structural parameter, and b is the second structural parameter.

[0097] That is, after determining a and b, determine U(y), then take the derivative of U(y) to get -U′(y), and then according to the equation We can then find y(t).

[0098] Due to the complexity of the power network, the fault signal is affected by other electrical or non-electrical quantities, so that the fault traveling wave is affected by high-frequency noise. Especially when the transition resistance is large or the initial phase angle of the fault is small, the fault signal is weak and is affected by high-frequency noise, making it difficult to extract the fault traveling wave signal and difficult to detect the traveling wave head. The embodiment of the present application realizes the extraction and processing of the fault traveling wave signal through the random resonance method. After the random resonance system resonates, the amplified effective signal is obtained, and the noise signal is eliminated at the same time.

[0099] Optionally, the traveling wave arrival time includes: wave head time;

[0100] Optionally, the wave head is extracted for the traveling wave signal to be extracted, and the arrival time of the traveling wave corresponding to the measuring point is recorded, including:

[0101] The amplitude of the traveling wave signal to be extracted is analyzed, and the time corresponding to the highest amplitude point is determined as the wave head time corresponding to the measuring point.

[0102] In this embodiment, the wave head time can be understood as the arrival time of the fault traveling wave head. The amplitude of the traveling wave signal to be extracted is analyzed to determine the amplitude at different times; the point with the highest amplitude is determined, and the time corresponding to this point is determined as the wave head time corresponding to the measuring point.

[0103] Optionally, the traveling wave arrival time includes: wave head time, reflection time and refraction time;

[0104] Optionally, the wave head is extracted for the traveling wave signal to be extracted, and the arrival time of the traveling wave corresponding to the measuring point is recorded, including:

[0105] The amplitude of the traveling wave signal to be extracted is analyzed, and the time corresponding to the highest amplitude point is determined as the wave head time, the time corresponding to the second highest amplitude point is determined as the reflection time, and the time corresponding to the third highest amplitude point is determined as the refraction time.

[0106] In this embodiment, the reflection time can be understood as the time it takes for the traveling wave to reach the measuring point again after being reflected by the fault point during the conduction process; the refraction time can be understood as the time it takes for the traveling wave to reach the measuring point on the other side after being refracted by the fault point during the conduction process.

[0107] The amplitude of the traveling wave signal to be extracted is analyzed to determine the amplitude at different times, the highest point, the second highest point and the third highest point of the amplitude, the time corresponding to the highest point of the amplitude is determined as the wave head time, the time corresponding to the second highest point of the amplitude is determined as the reflection time, and the time corresponding to the third highest point of the amplitude is determined as the refraction time.

[0108] For example, Figure 4 An example diagram of the arrival time of a traveling wave is provided, where K is the fault location, and M and N are the measurement points. M1 is the wave head time corresponding to the measuring point M, T M2 is the reflection time corresponding to the measuring point M, T NM1 is the refraction time corresponding to the measuring point M; T N1 is the wave head time corresponding to the measuring point N, T N2 is the reflection time corresponding to the measuring point N, T MN1 is the refraction time corresponding to the measuring point N. 1中间 is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point M, T 2中间 It is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point N.

[0109] Alternatively, the traveling wave head can be extracted and the arrival time sequence of the fault traveling wave can be recorded in the following way: when a fault occurs at point K, a traveling wave ranging device is set at point M and point N respectively; for point M, the wave head time T is first detected. M1 , and randomly inject a marker signal B into the line M1 , the signal is reflected by point k and arrives at point M again, denoted as T M2 , and inject B M2 Similarly, for point N, the wave head time T is detected N1 , and randomly inject a marker signal B into the line N1 , the signal is reflected by point k and arrives at point N again, denoted as T N2 , and inject B N2 The traveling wave is not only reflected but also refracted during the transmission process. Point M detects the wave with the marker B. N1 The signal is the refracted signal, and the time mark is T NM1 Similarly, the N points detected with the mark B M1 The signal is the refracted signal, and the time mark is T MN1 .

[0110] S209: perform fault location according to the arrival time of the traveling wave corresponding to each measuring point and the total length of the line to determine the fault position.

[0111] Determine the traveling wave transmission speed, or take the traveling wave transmission speed as the unknown quantity, use the traveling wave arrival time as the time, the total line length as the distance, determine the equation group according to the kinematic formula of time, speed and distance, and obtain the distance between the fault point and the measuring point by solving the equation group to realize fault location.

[0112] Optionally, the traveling wave arrival time includes: wave head time;

[0113] Optionally, when the transmission speeds of the traveling waves of the lines are equal, the fault location is determined based on the arrival time of the traveling waves corresponding to each measuring point and the total length of the line, including:

[0114] B1. Calculate the time difference according to the wave head time corresponding to each measuring point;

[0115] B2. Calculate the transmission distance based on the product of the time difference and the line beam transmission speed;

[0116] B3. Determine the fault distance based on the difference between the total line length and the transmission distance, and determine the fault location based on the fault distance.

[0117] Subtract the wave head times corresponding to the two measuring points and calculate the time difference; if the line beam transmission speeds on both sides of the fault point are equal, the line beam transmission speed can be determined in advance; calculate the product of the time difference and the line beam transmission speed to obtain the transmission distance, which can be the distance from the measuring point M to the fault point K, or the distance from the measuring point N to the fault point K; if the time difference = T M1 -T N1 , then the transmission distance is the distance from N to K. The difference between the total line length and the transmission distance is calculated, and the fault distance is the distance from M to K. If the time difference = T N1 -T M1 , then the transmission distance is the distance from M to K. The difference between the total line length and the transmission distance is calculated, and the fault distance is the distance from N to K. The location of the measuring point is known. After determining the fault distance, the fault location is determined based on the fault distance and the location of the measuring point.

[0118] Exemplarily, the present application embodiment provides a formula for calculating the fault distance:

[0119]

[0120] Among them, T M1 and T N1are the wave head time of measuring point M and the wave head time of measuring point N, respectively; v1 is the line beam transmission speed from measuring point M to fault point K; v2 is the line beam transmission speed from measuring point N to fault point K; L MK is the fault distance from the measuring point M to the fault point K, L NK is the fault distance from the measuring point N to the fault point K.

[0121] If the line beam transmission speed is equal but unknown, the fault distance can be calculated by the above formula, combined with L = L MK +L NK , three formulas, three unknown quantities can be solved to get L MK , L NK and v1 (or v2).

[0122] Optionally, the traveling wave arrival time includes: wave head time, reflection time and refraction time;

[0123] Optionally, when the line traveling wave transmission speed is different, the fault location is performed according to the traveling wave arrival time corresponding to each measuring point and the total length of the line to determine the fault location, including:

[0124] C1. Substitute the traveling wave arrival time corresponding to each measuring point and the total line length into the fault distance calculation formula to obtain the fault distance, where the fault distance includes at least one of a first fault distance and a second fault distance.

[0125] In this embodiment, the first fault distance and the second fault distance can be understood as the distance between the fault point K and the measuring point; taking the measuring points M and N as an example, the first fault distance is the distance between M and the fault point K, and the second fault distance is the distance between N and K, or the first fault distance is the distance between N and the fault point K, and the second fault distance is the distance between M and K. When calculating the fault distance, since the position of the measuring point is determined, it is only necessary to calculate the distance between the fault point and one measuring point, that is, at least one of the first fault distance and the second fault distance. The fault distance calculation formula can be understood as a set of equations for calculating the fault distance, which can be predetermined and directly substituted into each parameter variable when calculating the fault distance.

[0126] The fault distance calculation formula is determined in advance, and the traveling wave arrival time corresponding to each measuring point and the total line length are substituted into the fault distance calculation formula for calculation. The fault distance is obtained by solving the equation group.

[0127] C2. Determine the fault location based on the fault distance.

[0128] The location of the measuring point is known. After the fault distance is determined, the fault location is determined based on the fault distance and the location of the measuring point.

[0129] The fault distance calculation formula is as follows:

[0130]

[0131] Among them, T M1 is the wave head time corresponding to the measuring point M, T M2 is the reflection time corresponding to the measuring point M, T NM1 is the refraction time corresponding to the measuring point M, T N1 is the wave head time corresponding to the measuring point N, T N2 is the reflection time corresponding to the measuring point N, T MN1 is the refraction time corresponding to the measuring point N, L is the total length of the line; MK is the first fault distance, L NK is the second fault distance, v1 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point M, v2 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point N, T 1中间 is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point M, T 2中间 It is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point N.

[0132] By extracting the wave head, the arrival time of the traveling wave at the measuring point M and the measuring point N is obtained. The arrival time and the total length of the line are substituted into the above formula to calculate L. NK and L MK At least one of them can realize fault location. M1 、T M2 、T NM1 、T N1 、T N2 、T MN1 and L are known quantities, and the unknown quantities can be obtained by solving them. When the line traveling wave transmission speed is inconsistent, v1 and v2 are used to represent the average speed, and then the fault distance is calculated.

[0133] For example, Figure 5 A fault location implementation example diagram is provided, including the following process steps:

[0134] S1. Signal acquisition.

[0135] The power frequency signal z(t) is obtained through signal acquisition. By detecting the power frequency signal, it is determined whether the starting conditions of the traveling wave analysis are met. If so, the traveling wave detection is started; if not, the detection is not started.

[0136] S2, traveling wave start detection.

[0137] After the traveling wave start detection, the fault traveling wave signal x(t) is obtained.

[0138] S3. Fault traveling wave signal extraction.

[0139] By performing system resonance on the fault traveling wave signal, the traveling wave signal y(t) to be extracted is obtained.

[0140] S4. Use ranging positioning algorithm to perform positioning.

[0141] Extract the wave head of y(t) to get the arrival time T of the traveling wave M and T N , where T N Refers to the arrival time of the traveling wave corresponding to the measuring point N, T M Refers to the arrival time of the traveling wave corresponding to the measuring point M.

[0142] The fault is located by using the distance measurement and positioning algorithm to determine the fault distance L NK and L MK .

[0143] The fault location method provided by the embodiment of the present invention solves the problems of inaccurate acquisition of fault traveling wave signals and inaccurate wave head extraction. By using the detection method of the waveform energy function as the starting condition for recording, the accuracy of wave head start detection is improved, and the untimely or inaccurate fault analysis caused by the untimely start of recording is avoided; a wave head resonance method is proposed to extract effective traveling waves and eliminate interference signals, thereby further improving the accuracy and efficiency of wave head detection, which is more conducive to traveling wave identification in complex line environments, and further constructing a fault location verification algorithm to achieve verification; when performing fault location, considering the influence of the propagation speed in complex situations, different traveling wave ranging formulas are established to perform fault location, thereby achieving precise positioning.

[0144] Embodiment 3

[0145] Figure 6 This is a schematic diagram of the structure of a fault location device provided in Embodiment 3 of the present invention. Figure 6 As shown, the device includes: a fault traveling wave acquisition module 31, a wave head extraction module 32 and a fault location module 33.

[0146] A fault traveling wave acquisition module 31 is used to acquire a set of fault traveling wave signals to be analyzed at two measuring points of the line when it is detected that a traveling wave analysis start condition is met, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to a gain function of the power frequency signal;

[0147] The wave head extraction module 32 is used for constructing a stochastic resonance system potential function according to each fault traveling wave signal set, performing system resonance on the fault traveling wave signal according to the stochastic resonance system potential function to obtain a traveling wave signal to be extracted; performing wave head extraction on the traveling wave signal to be extracted, and recording the arrival time of the traveling wave corresponding to the measuring point;

[0148] The fault location module 33 is used to locate the fault according to the arrival time of the traveling wave corresponding to each of the measuring points and the total length of the line to determine the fault position.

[0149] The fault locating device provided by the embodiment of the present invention solves the problems of inaccurate acquisition of fault traveling wave signals and inaccurate wave head extraction. The traveling wave analysis start condition is determined by the gain function of the power frequency signal, thereby ensuring the accurate start timing of the traveling wave analysis, avoiding untimely or inaccurate fault analysis caused by untimely recording start, and improving the accuracy of wave head start detection. The fault traveling wave signal is subjected to system resonance by constructing a random resonance system potential function to obtain a traveling wave signal to be extracted, and the wave head of the traveling wave signal to be extracted is extracted to improve the accuracy of wave head recognition. The fault is accurately located according to the wave head arrival time, thereby improving the accuracy of fault location and achieving precise positioning.

[0150] Optionally, the device further comprises:

[0151] A power frequency signal acquisition module, used to acquire a first power frequency signal and a second power frequency signal;

[0152] A signal energy determination module, configured to perform waveform energy integration on the first power frequency signal to obtain first signal energy, and perform waveform energy integration on the second power frequency signal to obtain second signal energy;

[0153] A gain function calculation module, configured to calculate a gain function according to the first signal energy and the second signal energy;

[0154] The start judgment module is used to determine that the traveling wave analysis start condition is met when the gain function is greater than or equal to a predetermined gain function threshold.

[0155] Optionally, the first power frequency signal and the second power frequency signal are collected in two different collection cycles, and an initial collection point of the first power frequency signal differs from an initial collection point of the second power frequency signal by one collection cycle.

[0156] Optionally, the gain function calculation module includes:

[0157] an energy difference determination unit, configured to calculate a difference between the second signal energy and the first signal energy to obtain an energy difference;

[0158] an energy sum calculation unit, configured to calculate the sum of the second signal energy and the first signal energy to obtain an energy sum;

[0159] A gain function determining unit is used to use the ratio of the energy difference to the energy sum as a gain function.

[0160] Optionally, the wave head extraction module includes:

[0161] a structural parameter determination unit, configured to determine a first structural parameter and a second structural parameter based on the fault traveling wave signal set;

[0162] A potential function construction unit is used to construct a stochastic resonance system potential function according to the first structural parameter and the second structural parameter.

[0163] Optionally, the structural parameter determination unit is specifically used to:

[0164] Acquire a first fault traveling wave signal, a second fault traveling wave signal, a third fault traveling wave signal and a fourth fault traveling wave signal from the fault traveling wave signal set, wherein the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are fault traveling wave signals collected in different adjacent sampling periods;

[0165] constructing a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solving the traveling wave signal relationship function to obtain a first structural parameter and a second structural parameter;

[0166] Wherein, the expression of the traveling wave signal relationship function is:

[0167]

[0168] Among them, x(t) is the first fault traveling wave signal, x(t+Δt) is the second fault traveling wave signal, x(t+2Δt) is the third fault traveling wave signal, and x(t+3Δt) is the fourth fault traveling wave signal; a is the first structural parameter, b is the second structural parameter; s(t) is the effective fault traveling wave signal, z(t) is the noise signal, k1 is the slope at the beginning of the time period, k2 and k3 are the slopes at the midpoint of the time period, k4 is the slope at the end of the time period, and △t is the sampling period of the fault traveling wave signal.

[0169] Optionally, the structural parameter determination unit is further used to:

[0170] Determining whether the first structural parameter and the second structural parameter satisfy a stability condition;

[0171] If not satisfied, then re-obtain new first fault traveling wave signal, second fault traveling wave signal, third fault traveling wave signal and fourth fault traveling wave signal from the fault traveling wave signal set, and return to execute to construct a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solve the traveling wave signal relationship function to obtain first structural parameters and second structural parameters, until the first structural parameters and the second structural parameters meet the stability conditions.

[0172] Optionally, the wave head extraction module includes:

[0173] The signal method unit is used to perform cooperative resonance on the fault traveling wave signal through the potential function of the random resonance system, amplify the effective signal in the fault traveling wave signal, and obtain the traveling wave signal to be extracted.

[0174] Optionally, the traveling wave arrival time includes: wave head time;

[0175] The wave head extraction module comprises:

[0176] The first wave head extraction unit is used to analyze the amplitude of the traveling wave signal to be extracted, and determine the time corresponding to the highest amplitude point as the wave head time corresponding to the measuring point.

[0177] Optionally, the traveling wave arrival time includes: wave head time;

[0178] When the line traveling wave transmission speeds are equal, the fault location module includes:

[0179] A time difference calculation unit, used for calculating the time difference according to the wave head time corresponding to each of the measuring points;

[0180] A transmission distance calculation unit, used to calculate the transmission distance according to the product of the time difference and the line beam transmission speed;

[0181] The first fault locating unit is used to determine the fault distance based on the difference between the total line length and the transmission distance, and determine the fault position according to the fault distance.

[0182] Optionally, the traveling wave arrival time includes: wave head time, reflection time and refraction time;

[0183] The wave head extraction module comprises:

[0184] The second wave head extraction unit is used to analyze the amplitude of the traveling wave signal to be extracted, determine the time corresponding to the highest amplitude point as the wave head time, determine the time corresponding to the second highest amplitude point as the reflection time, and determine the time corresponding to the third highest amplitude point as the refraction time.

[0185] Optionally, the traveling wave arrival time includes: wave head time, reflection time and refraction time;

[0186] When the line traveling wave transmission speeds are different, the fault location module includes:

[0187] a fault distance determination unit, configured to substitute the traveling wave arrival time corresponding to each of the measuring points and the total line length into a fault distance calculation formula to calculate and obtain a fault distance, wherein the fault distance includes at least one of a first fault distance and a second fault distance;

[0188] A second fault locating unit, configured to determine a fault location according to the fault distance;

[0189] The fault distance calculation formula is as follows:

[0190]

[0191] Among them, T M1 is the wave head time corresponding to the measuring point M, T M2 is the reflection time corresponding to the measuring point M, T NM1 is the refraction time corresponding to the measuring point M, T N1 is the wave head time corresponding to the measuring point N, T N2 is the reflection time corresponding to the measuring point N, T MN1 is the refraction time corresponding to the measuring point N, L is the total length of the line; MK is the first fault distance, L NK is the second fault distance, v1 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point M, v2 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point N, T 1中间 is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point M, T 2中间 It is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point N.

[0192] The fault location device provided in the embodiment of the present invention can execute the fault location method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0193] Embodiment 4

[0194] Figure 7A schematic diagram of the structure of an electronic device 40 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0195] like Figure 7 As shown, the electronic device 40 includes at least one processor 41, and a memory connected to the at least one processor 41, such as a read-only memory (ROM) 42, a random access memory (RAM) 43, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 41 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 42 or the computer program loaded from the storage unit 48 to the random access memory (RAM) 43. In the RAM 43, various programs and data required for the operation of the electronic device 40 can also be stored. The processor 41, the ROM 42, and the RAM 43 are connected to each other through a bus 44. An input / output (I / O) interface 45 is also connected to the bus 44.

[0196] A number of components in the electronic device 40 are connected to the I / O interface 45, including: an input unit 46, such as a keyboard, a mouse, etc.; an output unit 47, such as various types of displays, speakers, etc.; a storage unit 48, such as a disk, an optical disk, etc.; and a communication unit 49, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 49 allows the electronic device 40 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0197] The processor 41 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 41 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 41 executes the various methods and processes described above, such as a fault location method.

[0198] In some embodiments, the fault location method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 48. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 40 via the ROM 42 and / or the communication unit 49. When the computer program is loaded into the RAM 43 and executed by the processor 41, one or more steps of the fault location method described above may be performed. Alternatively, in other embodiments, the processor 41 may be configured to perform the fault location method in any other appropriate manner (e.g., by means of firmware).

[0199] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0200] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0201] An embodiment of the present invention provides a computer program product. The computer program product includes a computer program. When the computer program is executed by a processor, the fault location method described in any embodiment of the present invention is implemented.

[0202] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0203] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0204] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0205] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0206] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0207] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fault location method, characterized in that: include: When it is detected that the traveling wave analysis start condition is met, a set of fault traveling wave signals to be analyzed of two measuring points of the line is obtained, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to a gain function of the power frequency signal; For each set of fault traveling wave signals, a stochastic resonance system potential function is constructed according to the set of fault traveling wave signals, and a system resonance is performed on the fault traveling wave signals according to the stochastic resonance system potential function to obtain traveling wave signals to be extracted; a wave head is extracted from the traveling wave signals to be extracted, and the arrival time of the traveling wave corresponding to the measuring point is recorded; The fault location is performed according to the arrival time of the traveling wave corresponding to each measuring point and the total length of the line to determine the fault position.

2. The method according to claim 1, characterized in that Also includes: Acquire a first power frequency signal and a second power frequency signal; Performing waveform energy integration on the first power frequency signal to obtain first signal energy, and performing waveform energy integration on the second power frequency signal to obtain second signal energy; Calculating a gain function based on the first signal energy and the second signal energy; When the gain function is greater than or equal to a predetermined gain function threshold, it is determined that the traveling wave analysis start condition is met.

3. The method according to claim 2, characterized in that The first power frequency signal and the second power frequency signal are collected in two different collection cycles, and an initial collection point of the first power frequency signal differs from an initial collection point of the second power frequency signal by one collection cycle.

4. The method according to claim 2, characterized in that: The calculating a gain function according to the first signal energy and the second signal energy comprises: Calculating a difference between the second signal energy and the first signal energy to obtain an energy difference; Calculating the sum of the second signal energy and the first signal energy to obtain an energy sum; The ratio of the energy difference to the energy sum is used as a gain function.

5. The method according to claim 1, characterized in that The step of constructing a stochastic resonance system potential function according to the fault traveling wave signal set includes: Determining a first structural parameter and a second structural parameter based on the fault traveling wave signal set; A stochastic resonance system potential function is constructed according to the first structural parameter and the second structural parameter.

6. The method according to claim 5, characterized in that The determining of the first structural parameter and the second structural parameter based on the fault traveling wave signal set comprises: Acquire a first fault traveling wave signal, a second fault traveling wave signal, a third fault traveling wave signal and a fourth fault traveling wave signal from the fault traveling wave signal set, wherein the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are fault traveling wave signals collected in different adjacent sampling periods; constructing a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solving the traveling wave signal relationship function to obtain a first structural parameter and a second structural parameter; Wherein, the expression of the traveling wave signal relationship function is: Among them, x(t) is the first fault traveling wave signal, x(t+Δt) is the second fault traveling wave signal, x(t+2Δt) is the third fault traveling wave signal, and x(t+3Δt) is the fourth fault traveling wave signal; a is the first structural parameter, b is the second structural parameter; s(t) is the effective fault traveling wave signal, z(t) is the noise signal, k1 is the slope at the beginning of the time period, k2 and k3 are the slopes at the midpoint of the time period, k4 is the slope at the end of the time period, and △t is the sampling period of the fault traveling wave signal.

7. The method according to claim 6, characterized in that After determining the first structural parameter and the second structural parameter based on the fault traveling wave signal set, the method further includes: Determining whether the first structural parameter and the second structural parameter satisfy a stability condition; If not satisfied, then re-obtain new first fault traveling wave signal, second fault traveling wave signal, third fault traveling wave signal and fourth fault traveling wave signal from the fault traveling wave signal set, and return to execute to construct a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solve the traveling wave signal relationship function to obtain first structural parameters and second structural parameters, until the first structural parameters and the second structural parameters meet the stability conditions.

8. The method according to claim 1, characterized in that The step of performing system resonance on the fault traveling wave signal according to the stochastic resonance system potential function to obtain the traveling wave signal to be extracted includes: The fault traveling wave signal is cooperatively resonated by the potential function of the stochastic resonance system, and the effective signal in the fault traveling wave signal is amplified to obtain the traveling wave signal to be extracted.

9. The method according to claim 1, characterized in that: The traveling wave arrival time includes: wave head time; The step of extracting the wave head of the traveling wave signal to be extracted and recording the arrival time of the traveling wave corresponding to the measuring point includes: The amplitude of the traveling wave signal to be extracted is analyzed, and the time corresponding to the highest amplitude point is determined as the wave head time corresponding to the measuring point.

10. The method according to claim 1, characterized in that The traveling wave arrival time includes: wave head time; When the line traveling wave transmission speeds are equal, the fault location is performed according to the traveling wave arrival time corresponding to each measuring point and the total length of the line to determine the fault position, including: Calculate the time difference according to the wave head time corresponding to each of the measuring points; Calculating the transmission distance according to the product of the time difference and the line beam transmission speed; The fault distance is determined based on the difference between the total line length and the transmission distance, and the fault position is determined according to the fault distance.

11. The method according to claim 1, characterized in that: The traveling wave arrival time includes: wave head time, reflection time and refraction time; The step of extracting the wave head of the traveling wave signal to be extracted and recording the arrival time of the traveling wave corresponding to the measuring point includes: The amplitude of the traveling wave signal to be extracted is analyzed, and the time corresponding to the highest amplitude point is determined as the wave head time, the time corresponding to the second highest amplitude point is determined as the reflection time, and the time corresponding to the third highest amplitude point is determined as the refraction time.

12. The method according to claim 1, characterized in that The traveling wave arrival time includes: wave head time, reflection time and refraction time. When the line traveling wave transmission speed is different, the fault location is performed according to the traveling wave arrival time corresponding to each measuring point and the total length of the line to determine the fault position, including: Substituting the traveling wave arrival time corresponding to each of the measuring points and the total line length into a fault distance calculation formula to calculate and obtain a fault distance, wherein the fault distance includes at least one of a first fault distance and a second fault distance; determining a fault location according to the fault distance; The fault distance calculation formula is as follows: Among them, T M1 is the wave head time corresponding to the measuring point M, T M2 is the reflection time corresponding to the measuring point M, T NM1 is the refraction time corresponding to the measuring point M, T N1 is the wave head time corresponding to the measuring point N, T N2 is the reflection time corresponding to the measuring point N, T MN1 is the refraction time corresponding to the measuring point N, L is the total length of the line; MK is the first fault distance, L NK is the second fault distance, v1 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point M, v2 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point N, T 1中间 is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point M, T 2中间 It is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point N.

13. A fault location device, characterized in that: include: A fault traveling wave acquisition module is used to acquire a set of fault traveling wave signals to be analyzed of two measuring points of the line when it is detected that the traveling wave analysis start condition is met, wherein the set of fault traveling wave signals includes fault traveling wave signals collected at different sampling periods, and the traveling wave analysis start condition is determined according to the gain function of the power frequency signal; A wave head extraction module is used to construct a stochastic resonance system potential function according to each set of fault traveling wave signals, perform system resonance on the fault traveling wave signals according to the stochastic resonance system potential function, and obtain traveling wave signals to be extracted; perform wave head extraction on the traveling wave signals to be extracted, and record the arrival time of the traveling wave corresponding to the measuring point; The fault location module is used to locate the fault according to the arrival time of the traveling wave corresponding to each measuring point and the total length of the line to determine the fault position.

14. The device according to claim 13, characterized in that Also includes: A power frequency signal acquisition module, used to acquire a first power frequency signal and a second power frequency signal; A signal energy determination module, configured to perform waveform energy integration on the first power frequency signal to obtain first signal energy, and perform waveform energy integration on the second power frequency signal to obtain second signal energy; A gain function calculation module, configured to calculate a gain function according to the first signal energy and the second signal energy; The start judgment module is used to determine that the traveling wave analysis start condition is met when the gain function is greater than or equal to a predetermined gain function threshold.

15. The device according to claim 14, characterized in that The first power frequency signal and the second power frequency signal are collected in two different collection cycles, and an initial collection point of the first power frequency signal differs from an initial collection point of the second power frequency signal by one collection cycle.

16. The device according to claim 14, characterized in that The gain function calculation module comprises: an energy difference determination unit, configured to calculate a difference between the second signal energy and the first signal energy to obtain an energy difference; an energy sum calculation unit, configured to calculate the sum of the second signal energy and the first signal energy to obtain an energy sum; A gain function determining unit is used to use the ratio of the energy difference to the energy sum as a gain function.

17. The device according to claim 13, characterized in that The wave head extraction module comprises: a structural parameter determination unit, configured to determine a first structural parameter and a second structural parameter based on the fault traveling wave signal set; A potential function construction unit is used to construct a stochastic resonance system potential function according to the first structural parameter and the second structural parameter.

18. The device according to claim 17, characterized in that The structural parameter determination unit is specifically used for: Acquire a first fault traveling wave signal, a second fault traveling wave signal, a third fault traveling wave signal and a fourth fault traveling wave signal from the fault traveling wave signal set, wherein the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal are fault traveling wave signals collected in different adjacent sampling periods; constructing a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solving the traveling wave signal relationship function to obtain a first structural parameter and a second structural parameter; Wherein, the expression of the traveling wave signal relationship function is: Among them, x(t) is the first fault traveling wave signal, x(t+Δt) is the second fault traveling wave signal, x(t+2Δt) is the third fault traveling wave signal, and x(t+3Δt) is the fourth fault traveling wave signal; a is the first structural parameter, b is the second structural parameter; s(t) is the effective fault traveling wave signal, z(t) is the noise signal, k1 is the slope at the beginning of the time period, k2 and k3 are the slopes at the midpoint of the time period, k4 is the slope at the end of the time period, and △t is the sampling period of the fault traveling wave signal.

19. The device according to claim 18, characterized in that The structural parameter determination unit is further used for: Determining whether the first structural parameter and the second structural parameter satisfy a stability condition; If not satisfied, then re-obtain new first fault traveling wave signal, second fault traveling wave signal, third fault traveling wave signal and fourth fault traveling wave signal from the fault traveling wave signal set, and return to execute to construct a traveling wave signal relationship function according to the first fault traveling wave signal, the second fault traveling wave signal, the third fault traveling wave signal and the fourth fault traveling wave signal, and solve the traveling wave signal relationship function to obtain first structural parameters and second structural parameters, until the first structural parameters and the second structural parameters meet the stability conditions.

20. The device according to claim 13, characterized in that The wave head extraction module comprises: The signal method unit is used to perform cooperative resonance on the fault traveling wave signal through the potential function of the random resonance system, amplify the effective signal in the fault traveling wave signal, and obtain the traveling wave signal to be extracted.

21. The device according to claim 13, characterized in that The traveling wave arrival time includes: wave head time; The wave head extraction module comprises: The first wave head extraction unit is used to analyze the amplitude of the traveling wave signal to be extracted, and determine the time corresponding to the highest amplitude point as the wave head time corresponding to the measuring point.

22. The device according to claim 13, characterized in that The traveling wave arrival time includes: wave head time; When the line traveling wave transmission speeds are equal, the fault location module includes: A time difference calculation unit, used for calculating the time difference according to the wave head time corresponding to each of the measuring points; A transmission distance calculation unit, used to calculate the transmission distance according to the product of the time difference and the line beam transmission speed; The first fault locating unit is used to determine the fault distance based on the difference between the total line length and the transmission distance, and determine the fault position according to the fault distance.

23. The device according to claim 13, characterized in that The traveling wave arrival time includes: wave head time, reflection time and refraction time; The wave head extraction module comprises: The second wave head extraction unit is used to analyze the amplitude of the traveling wave signal to be extracted, determine the time corresponding to the highest amplitude point as the wave head time, determine the time corresponding to the second highest amplitude point as the reflection time, and determine the time corresponding to the third highest amplitude point as the refraction time.

24. The device according to claim 13, characterized in that The traveling wave arrival time includes: wave head time, reflection time and refraction time; When the line traveling wave transmission speeds are different, the fault location module includes: a fault distance determination unit, configured to substitute the traveling wave arrival time corresponding to each of the measuring points and the total line length into a fault distance calculation formula to calculate and obtain a fault distance, wherein the fault distance includes at least one of a first fault distance and a second fault distance; A second fault locating unit, configured to determine a fault location according to the fault distance; The fault distance calculation formula is as follows: Among them, T M1 is the wave head time corresponding to the measuring point M, T M2 is the reflection time corresponding to the measuring point M, T NM1 is the refraction time corresponding to the measuring point M, T N1 is the wave head time corresponding to the measuring point N, T N2 is the reflection time corresponding to the measuring point N, T MN1 is the refraction time corresponding to the measuring point N, L is the total length of the line; MK is the first fault distance, L NK is the second fault distance, v1 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point M, v2 is the transmission speed of the fault traveling wave signal between the fault location K and the measuring point N, T 1中间 is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point M, T 2中间 It is the time it takes for the fault traveling wave signal to reach the fault location K after being reflected by point N.

25. An electronic device, characterized in that: The electronic device comprises: at least one processor, and a memory communicatively coupled to the at least one processor; The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the fault location method according to any one of claims 1 to 12.

26. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the fault location method according to any one of claims 1 to 12 when executed.

27. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the fault localization method according to any one of claims 1 to 12 is implemented.

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