Method, device and medium for locating power distribution network line fault based on traveling wave ranging

Abstract

A power distribution network line fault positioning method and device based on traveling wave ranging, and a medium, comprising judging whether a line fault occurs and judging a fault time through high-speed sampling of a traveling wave current signal on the power distribution network line, and checking the fault time calculated by a power frequency algorithm to determine whether to save the fault traveling wave data and report the power distribution network line fault, and performing double-end ranging according to the saved fault traveling wave data to position the fault on the power distribution network line. The present application positions the fault on the power distribution network line based on the traveling wave ranging technology, which can measure the fault distance by using the time difference between the fault point and the measurement point. This method is not affected by factors such as transition resistance of the fault point and line structure, so the ranging accuracy is high.

Description

Technical Field

[0001] This invention relates to the field of power distribution network technology, and specifically to a method, device, and storage medium for locating power distribution network line faults based on traveling wave ranging. Background Technology

[0002] With the acceleration of urbanization and the continuous growth of electricity demand, the power distribution network, as the final link in power transmission and distribution, is becoming increasingly complex and important. However, frequent short circuits and grounding faults in the distribution network not only affect users' normal electricity consumption but can also damage grid equipment and even trigger wider power outages. Traditional methods for fault location in distribution networks, such as manual inspection and fault indicator-based location, suffer from problems such as long location times, low accuracy, and high labor costs, making it difficult to meet the requirements of modern distribution networks for rapid response and precise location. Therefore, developing efficient and high-precision fault location technology for distribution networks is particularly important.

[0003] Traveling wave ranging technology, as a fault location method based on the propagation characteristics of transient traveling waves, provides a new approach to solving the problem of fault location in distribution networks. In distribution networks, transient traveling waves generated by faults propagate rapidly along the lines and are reflected and transmitted when they encounter impedance discontinuities (such as fault points, branch points, etc.). By accurately measuring the propagation time of the traveling wave between the fault point and the measurement point, and combining this with the propagation speed of the traveling wave in the conductor, the fault point can be accurately located.

[0004] Currently, methods for fault location in distribution networks using traveling wave ranging include fault information devices based on FPGAs and ARMs. However, these methods require time to transmit fault information between different platform devices, resulting in poor real-time performance. Other methods rely on AD sampling of current signals to determine the initiation of traveling waves, but these do not consider the high noise levels on distribution network lines, making them prone to false initiation and exhibiting weak anti-interference capabilities. Furthermore, most current traveling wave ranging methods do not consider handling transient continuous faults, leading to poor universality. Therefore, a high-precision fault location method for distribution network lines is urgently needed, offering good real-time performance, strong anti-interference capabilities, and universal applicability. Summary of the Invention

[0005] The present invention proposes a method, device and storage medium for locating faults in power distribution lines based on traveling wave ranging, which can at least solve one of the technical problems in the background art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for locating faults in distribution network lines based on traveling wave ranging includes the following steps:

[0008] Step 1: High-speed sampling of traveling wave current signals on the distribution network lines to determine whether a fault has occurred on the line and to determine the fault time. The fault time is then compared with the fault time calculated by the power frequency algorithm to determine whether to save the traveling wave waveform data of this fault and to report the fault in the distribution network line.

[0009] Step 2: Based on the saved fault traveling wave data, both ends of the distribution network line perform double-end ranging to locate the fault location on the distribution network line.

[0010] Furthermore, step 1 specifically includes the following steps:

[0011] Step 1.1: Using a current transformer, the current of M amperes on the distribution network line is converted into a voltage of N volts. The converted voltage value is continuously sampled at a frequency of 0 Hz. A digital array P is obtained for each sampling cycle, where P = ( , ,..., ,..., Using the BeiDou satellite navigation system and a high-precision crystal oscillator with pressure-controlled regulation for time synchronization and timekeeping, the time array T corresponding to each digital value in the digital array P is accurately obtained, where T = ( , ,..., ,..., ), where u is the index of the numeric value in the numeric array, u= , ,...,μ,p u This represents the numeric value with index u, and each numeric value p u The corresponding time is t u ;

[0012] Step 1.2, change the number value p in the number array P. u Compared with a threshold Q, when R consecutive numerical values ​​are greater than the threshold, i.e. , ,..., When all values ​​are greater than Q, the digital array P of this period satisfies the ripple initiation condition. Record the corresponding time array T, and then... u The given millisecond time and the number of oscillations of the crystal oscillator m milliseconds prior are used to calibrate the time array T using the calibration value θ, resulting in the calibrated time array I, where I = ( , ,..., ,..., ), i u =t u +θ,p u Corresponding calibration time i u This refers to the time of the fault as determined, and the time of the fault as determined is denoted as τ.

[0013] Step 1.3: Place the digital array P that meets the ripple initiation conditions from Step 1.2 into the ripple data buffer queue S, where S = { , ,..., ,..., }, Let τ be the fault time and u be the sequence number. The data waiting time W in the ripple data buffer queue S is compared with the time calculated by the power frequency algorithm. If the power frequency algorithm does not provide a calculated fault time within W, then this ripple initiation is a false initiation caused by noise, and the data set with fault time τ in the ripple data buffer queue S is discarded. If the power frequency algorithm provides a calculated fault time ε within W, then the difference α between the fault time determined by the ripple and the fault time calculated by the power frequency algorithm is calculated. ,in, The absolute value sign is indicated. If the value of α is greater than the fault time difference threshold λ, the data with fault time τ in the traveling wave data buffer queue S is discarded. If the value of α is less than the fault time difference threshold λ, the data with fault time τ in the traveling wave data buffer queue S is saved and the distribution network line fault is reported.

[0014] Step 1.4: Repeat steps 1.1 to 1.3 to monitor the traveling wave current signal on the distribution network line in real time. When a transient continuous fault occurs, add the digital array P that meets the traveling wave current initiation conditions to the traveling wave data buffer queue S.

[0015] S={ , ,..., ,..., , , ,..., ,..., ,..., ,

[0016] ,..., ,..., },in, , , The data waiting time W in the traveling wave data buffer queue S is compared with the fault time calculated by the power frequency algorithm to indicate different fault times. This determines whether to save the traveling wave data for this fault time and report the fault in the distribution network line.

[0017] Furthermore, the voltage-controlled adjustment method of the crystal oscillator described in step 1.1 is as follows:

[0018] Given the voltage A across a crystal oscillator chip and the number of oscillations per second (B), using the BeiDou satellite navigation system for timing, calculate the number of oscillations per second (C) and compare the difference γ between B and C. ,if If the voltage is ≤5, then the value of voltage A remains unchanged. If it continues for z seconds, >5, if γ>0, then adjust the voltage across the crystal oscillator chip to A+2; if γ<0, then adjust the voltage across the crystal oscillator chip to A-2, where, Indicates the absolute value symbol;

[0019] Calculate the average number of crystal oscillations, D, over the past 5 seconds, and compare the difference δ between B and D. If for z consecutive seconds, ≤4, adjust the voltage across the crystal oscillator chip to A+δ, if If the value is ≥10, the voltage across the crystal oscillator chip is directly adjusted to A+δ; otherwise, the voltage across the crystal oscillator chip is not adjusted.

[0020] Furthermore, in step 1.2, the calibration value θ is used to calibrate the time array T. The calibration value θ is calculated as follows:

[0021] Calculate t u The crystal oscillator counts within the given millisecond time period and the m milliseconds preceding it, and the crystal oscillator counts for these m+1 milliseconds are as follows: , ,..., ,..., ,in for Crystal oscillator count within the corresponding millisecond time period, For t u The crystal oscillator count from milliseconds ago (mb milliseconds ago) , ,...,0;

[0022] calculate arrive The sum of the crystal oscillator counts, sum = + +…+ The crystal oscillator count and sum are compared with the standard frequency H of the crystal oscillator used to calculate the difference in crystal oscillator count. , ;

[0023] The value of b is calculated starting from m, representing the crystal oscillator count difference. ,when <5, then ,when If the value is ≥5, then let b = b-1 and recalculate the crystal oscillator count difference. until <5 o'clock, order When b=0, ,in, Represents the absolute value symbol.

[0024] Furthermore, the specific steps of step 2 are as follows:

[0025] Step 2.1 When a fault occurs between the X and Y ends of the distribution network line, both the X and Y ends will save fault traveling wave data. Based on the fault traveling wave data saved at the X and Y ends, the sampling wavelet transform method is used to find the wavefront positions of the traveling wave data at both ends and their corresponding fault times x and y.

[0026] Step 2.2: Based on the fault time x obtained from end X and the fault time y obtained from end Y, calculate the distance L from the fault location to X. X , The distance L from Y Y , , where c represents the transmission speed of the traveling wave in the distribution network line from X to Y, and L represents the line length between X and Y.

[0027] In another aspect, the present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method described above.

[0028] In another aspect, the present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described above.

[0029] In summary, the present invention provides a method for locating faults in distribution network lines based on traveling wave ranging, which includes determining whether a fault has occurred in the line and determining the fault time by high-speed sampling of the traveling wave current signal on the distribution network line, verifying it with the fault time calculated by the power frequency algorithm, determining whether to save the traveling wave data of this fault and report the fault in the distribution network line, and performing double-end ranging at both ends of the distribution network line based on the saved fault traveling wave data to locate the fault location on the distribution network line.

[0030] Compared with the prior art, the advantages of this invention are as follows:

[0031] This invention utilizes traveling wave ranging technology to locate faults on distribution network lines. Traveling wave ranging technology measures the distance to the fault by utilizing the time difference of the traveling wave propagating between the fault point and the measurement point. This method is unaffected by factors such as the transition resistance of the fault point and the line structure, thus achieving high ranging accuracy. In contrast, traditional distribution network fault location methods, such as fault indicator-based methods, are susceptible to various interferences and errors, resulting in low accuracy. Furthermore, manual inspection methods are time-consuming and labor-intensive. This invention's traveling wave ranging technology employs the BeiDou satellite navigation system and a high-precision crystal oscillator with voltage-controlled regulation for time synchronization and monitoring. The fault time is calibrated based on the crystal oscillator count at the time of the fault, ensuring the synchronization and accuracy of different ranging devices on the distribution network line. This provides a guarantee for accurately locating faults in distribution network lines using traveling wave ranging technology. This invention stores traveling wave data of faulty lines and reports faults in distribution networks. It employs a method of verifying the fault time determined by traveling wave sampling with the fault time calculated using a power frequency algorithm. This eliminates the problem of false traveling wave initiation caused by high noise levels in distribution networks, enhancing the anti-interference capability of locating faults in distribution networks using traveling wave ranging technology. It is better adapted to complex and ever-changing distribution networks. This invention uses a queue to quickly cache all fault data and determined fault times that meet the traveling wave initiation conditions, then verifies them with the fault time calculated by the power frequency algorithm, saving the traveling wave data that meets the verification. This method can handle instantaneous continuous faults occurring on distribution network lines in real time, and can also promptly save fault traveling wave data when faults and noise occur simultaneously, giving the traveling wave ranging method of this invention a certain degree of universality. Attached Figure Description

[0032] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0034] A method for locating faults in distribution network lines based on traveling wave ranging includes determining whether a fault has occurred and the fault time by high-speed sampling of traveling wave current signals on the distribution network line, verifying the fault time with the fault time estimated by the power frequency algorithm, determining whether to save the traveling wave data of this fault and report the distribution network line fault, and performing double-end ranging at both ends of the distribution network line based on the saved fault traveling wave data to locate the fault position on the distribution network line. Specifically, the method includes the following steps:

[0035] Step 1: High-speed sampling of traveling wave current signals on distribution network lines to determine whether a fault has occurred and the fault time, and verification with the fault time calculated by the power frequency algorithm, to determine whether to save the traveling wave waveform data of this fault and report the distribution network line fault. The steps are as follows:

[0036] Step 1.1: Using a current transformer, the current of M amperes on the distribution network line is converted into a voltage of N volts. The converted voltage value is continuously sampled at a frequency of 0 Hz. A digital array P is obtained for each sampling cycle, where P = ( , ,..., ,..., Using the BeiDou satellite navigation system and a high-precision crystal oscillator with pressure-controlled regulation for time synchronization and timekeeping, the time array T corresponding to each digital value in the digital array P is accurately obtained, where T = ( , ,..., ,..., ), where u is the index of the numeric value in the numeric array, u= , ,...,μ,p u This represents the numeric value with index u, and each numeric value p u The corresponding time is t u ;

[0037] Step 1.2, change the number value p in the number array P. u Compared with a threshold Q, when R consecutive numerical values ​​are greater than the threshold, i.e. , ,..., When all values ​​are greater than Q, the digital array P of this period satisfies the ripple initiation condition. Record the corresponding time array T, and then... u The given millisecond time and the number of oscillations of the crystal oscillator m milliseconds prior are used to calibrate the time array T using the calibration value θ, resulting in the calibrated time array I, where I = ( , ,..., ,..., ), i u =t u +θ,p u Corresponding calibration time i u This refers to the time of the fault as determined, and the time of the fault as determined is denoted as τ.

[0038] Step 1.3: Place the digital array P that meets the ripple initiation conditions from Step 1.2 into the ripple data buffer queue S, where S = { , ,..., ,..., }, Let τ be the fault time and u be the sequence number. The data waiting time W in the ripple data buffer queue S is compared with the time calculated by the power frequency algorithm. If the power frequency algorithm does not provide a calculated fault time within W, then this ripple initiation is a false initiation caused by noise, and the data set with fault time τ in the ripple data buffer queue S is discarded. If the power frequency algorithm provides a calculated fault time ε within W, then the difference α between the fault time determined by the ripple and the fault time calculated by the power frequency algorithm is calculated. ,in, The absolute value sign is indicated. If the value of α is greater than the fault time difference threshold λ, the data with fault time τ in the traveling wave data buffer queue S is discarded. If the value of α is less than the fault time difference threshold λ, the data with fault time τ in the traveling wave data buffer queue S is saved and the distribution network line fault is reported.

[0039] Step 1.4: Repeat steps 1.1 to 1.3 to monitor the traveling wave current signal on the distribution network line in real time. When a transient continuous fault occurs, add the digital array P that meets the traveling wave current initiation conditions to the traveling wave data buffer queue S.

[0040] S={ , ,..., ,..., , , ,..., ,..., ,..., ,

[0041] ,..., ,..., },in, , , The data waiting time W in the traveling wave data buffer queue S is compared with the fault time calculated by the power frequency algorithm to indicate different fault times, and to determine whether to save the traveling wave data for this fault time and report the fault in the distribution network line.

[0042] The voltage-controlled adjustment method of the crystal oscillator described in step 1.1 is as follows:

[0043] Given the voltage A across a crystal oscillator chip and the number of oscillations per second (B), using the BeiDou satellite navigation system for timing, calculate the number of oscillations per second (C) and compare the difference γ between B and C. ,if If the voltage is ≤5, then the value of voltage A remains unchanged. If it continues for z seconds, >5, if γ>0, then adjust the voltage across the crystal oscillator chip to A+2; if γ<0, then adjust the voltage across the crystal oscillator chip to A-2, where, Indicates the absolute value symbol;

[0044] Calculate the average number of crystal oscillations, D, over the past 5 seconds, and compare the difference δ between B and D. If for z consecutive seconds, ≤4, adjust the voltage across the crystal oscillator chip to A+δ, if If the value is ≥10, the voltage across the crystal oscillator chip is directly adjusted to A+δ; otherwise, the voltage across the crystal oscillator chip is not adjusted.

[0045] Step 1.2 describes using the calibration value θ to calibrate the time array T. The calibration value θ is calculated as follows:

[0046] Calculate t u The crystal oscillator counts within the given millisecond time period and the m milliseconds preceding it, and the crystal oscillator counts for these m+1 milliseconds are as follows: , ,..., ,..., ,in for Crystal oscillator count within the corresponding millisecond time period, For t u The crystal oscillator count from milliseconds ago (mb milliseconds ago) , ,...,0;

[0047] calculate arrive The sum of the crystal oscillator counts, sum = + +…+ The crystal oscillator count and sum are compared with the standard frequency H of the crystal oscillator used to calculate the difference in crystal oscillator count. , ;

[0048] The value of b is calculated starting from m, representing the crystal oscillator count difference. ,when <5, then ,when If the value is ≥5, then let b = b-1 and recalculate the crystal oscillator count difference. until <5 o'clock, order When b=0, ,in, Represents the absolute value symbol.

[0049] Step 2: Based on the saved fault traveling wave data, perform double-end ranging at both ends of the distribution network line to locate the fault position on the distribution network line. The steps are as follows:

[0050] Step 2.1 When a fault occurs between the X and Y ends of the distribution network line, both the X and Y ends will save fault traveling wave data. Based on the fault traveling wave data saved at the X and Y ends, the sampling wavelet transform method is used to find the wavefront positions of the traveling wave data at both ends and their corresponding fault times x and y.

[0051] Step 2.2: Based on the fault time x obtained from end X and the fault time y obtained from end Y, calculate the distance L from the fault location to X. X , The distance L from Y Y , , where c represents the transmission speed of the traveling wave in the distribution network line from X to Y, and L represents the line length between X and Y.

[0052] For example, in a full-scale experimental field of a power distribution network with a line length of 4km, the fault point is set at 75% of the power distribution network line, that is, 3km from the X end and 1km from the Y end. For different grounding types and different grounding resistances, the above-mentioned invention method is used to locate the fault on the power distribution line. The ranging results are shown in Table 1-1 below. The ranging error of the method of the present invention for different fault types is controlled within 100m, realizing accurate fault location.

[0053] Table 1-1

[0054]

[0055] In another aspect, the present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method described above.

[0056] In another aspect, the present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described above.

[0057] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute any of the distribution network line fault location methods based on traveling wave ranging in the above embodiments.

[0058] It is understood that the systems, devices, and storage media provided in the embodiments of the present invention correspond to the methods provided in the embodiments of the present invention, and the explanations, examples, and beneficial effects of the relevant content can be referred to the corresponding parts of the above methods.

[0059] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0061] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0062] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for locating faults in distribution network lines based on traveling wave ranging, characterized in that, Includes the following steps, Step 1: High-speed sampling of traveling wave current signals on the distribution network lines to determine whether a fault has occurred on the line and to determine the fault time. The fault time is then compared with the fault time calculated by the power frequency algorithm to determine whether to save the traveling wave waveform data of this fault and to report the fault in the distribution network line. Step 2: Based on the saved fault traveling wave data, both ends of the distribution network line perform double-end ranging to locate the fault location on the distribution network line. Step 1 specifically includes the following steps: Step 1.1: Using a current transformer, the current of M amperes on the distribution network line is converted into a voltage of N volts. The converted voltage value is continuously sampled at a frequency of 0 Hz. A digital array P is obtained for each sampling cycle, where P = ( , ,..., ,..., Using the BeiDou satellite navigation system and a high-precision crystal oscillator with pressure-controlled regulation for time synchronization and timekeeping, the time array T corresponding to each digital value in the digital array P is accurately obtained, where T = ( , ,..., ,..., ), where u is the index of the numeric value in the numeric array, u= , ,...,μ,p u This represents the numeric value with index u, and each numeric value p u The corresponding time is t u ; Step 1.2, change the number value p in the number array P. u Compared with a threshold Q, when R consecutive numerical values ​​are greater than the threshold, i.e. , ,..., When all values ​​are greater than Q, the digital array P of this period satisfies the ripple initiation condition. Record the corresponding time array T, and then... u The given millisecond time and the number of oscillations of the crystal oscillator m milliseconds prior are used to calibrate the time array T using the calibration value θ, resulting in the calibrated time array I, where I = ( , ,..., ,..., ), i u =t u +θ,p u Corresponding calibration time i u This refers to the time of the fault as determined, and the time of the fault as determined is denoted as τ. Step 1.3: Place the digital array P that meets the ripple initiation conditions from Step 1.2 into the ripple data buffer queue S, where S = { , ,..., ,..., }, Let τ be the fault time and u be the sequence number. The data waiting time W in the ripple data buffer queue S is compared with the time calculated by the power frequency algorithm. If the power frequency algorithm does not provide a calculated fault time within W, then this ripple initiation is a false initiation caused by noise, and the data set with fault time τ in the ripple data buffer queue S is discarded. If the power frequency algorithm provides a calculated fault time ε within W, then the difference α between the fault time determined by the ripple and the fault time calculated by the power frequency algorithm is calculated. ,in, The absolute value sign is indicated. If the value of α is greater than the fault time difference threshold λ, the data with fault time τ in the traveling wave data buffer queue S is discarded. If the value of α is less than the fault time difference threshold λ, the data with fault time τ in the traveling wave data buffer queue S is saved and the distribution network line fault is reported. Step 1.4: Repeat steps 1.1 to 1.3 to monitor the traveling wave current signal on the distribution network line in real time. When a transient continuous fault occurs, add the digital array P that meets the traveling wave current initiation conditions to the traveling wave data buffer queue S. S={ , ,..., ,..., , , ,..., ,..., ,..., , ,..., ,..., },in, , , The data waiting time W in the traveling wave data buffer queue S is compared with the fault time calculated by the power frequency algorithm to indicate different fault times. This determines whether to save the traveling wave data for this fault time and report the fault in the distribution network line.

2. The method for locating faults in distribution network lines based on traveling wave ranging according to claim 1, characterized in that: The voltage-controlled adjustment method of the crystal oscillator described in step 1.1 is as follows: Given the voltage A across a crystal oscillator chip and the number of oscillations per second (B), using the BeiDou satellite navigation system for timing, calculate the number of oscillations per second (C) and compare the difference γ between B and C. ,if If the voltage is ≤5, then the value of voltage A remains unchanged. If it continues for z seconds, >5, if γ>0, then adjust the voltage across the crystal oscillator chip to A+2; if γ<0, then adjust the voltage across the crystal oscillator chip to A-2, where, Indicates the absolute value symbol; Calculate the average number of crystal oscillations, D, over the past 5 seconds, and compare the difference δ between B and D. If for z consecutive seconds, ≤4, adjust the voltage across the crystal oscillator chip to A+δ, if If the value is ≥10, the voltage across the crystal oscillator chip is directly adjusted to A+δ; otherwise, the voltage across the crystal oscillator chip is not adjusted.

3. The method for locating faults in distribution network lines based on traveling wave ranging according to claim 1, characterized in that: Step 1.2 describes using the calibration value θ to calibrate the time array T. The calibration value θ is calculated as follows: Calculate t u The crystal oscillator counts within the given millisecond time period and the m milliseconds preceding it, and the crystal oscillator counts for these m+1 milliseconds are as follows: , ,..., ,..., ,in for Crystal oscillator count within the corresponding millisecond time period, For t u The crystal oscillator count from milliseconds ago (mb milliseconds ago) belongs to this category. , ,...,0; calculate arrive The sum of the crystal oscillator counts, sum = + +…+ The crystal oscillator count and sum are compared with the standard frequency H of the crystal oscillator used to calculate the difference in crystal oscillator count. , ; The value of b is calculated starting from m, representing the crystal oscillator count difference. ,when <5, then ,when If the value is ≥5, then let b = b-1 and recalculate the crystal oscillator count difference. until <5 o'clock, order When b=0, ,in, Represents the absolute value symbol.

4. The method for locating faults in distribution network lines based on traveling wave ranging according to claim 1, characterized in that: Step 2 is detailed below: Step 2.1 When a fault occurs between the X and Y ends of the distribution network line, both the X and Y ends will save fault traveling wave data. Based on the fault traveling wave data saved at the X and Y ends, the sampling wavelet transform method is used to find the wavefront positions of the traveling wave data at both ends and their corresponding fault times x and y. Step 2.2: Based on the fault time x obtained from end X and the fault time y obtained from end Y, calculate the distance L from the fault location to X. X , The distance L from Y Y , , where c represents the transmission speed of the traveling wave in the distribution network line from X to Y, and L represents the line length between X and Y.

5. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 4.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the computer program is executed by the processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 4.

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