Cable fault positioning method, device and equipment and storage medium

Abstract

The invention discloses a cable fault positioning method, device and equipment and a storage medium, and relates to the technical field of fault positioning. The method comprises the following steps: acquiring impedance data of a to-be-detected cable; chirp-Z transformation is carried out on the impedance data to obtain positioning spectrum data, the positioning spectrum data comprises a corresponding relation between a normalized amplitude and a target distance, and the target distance is the distance from an acquisition point of the impedance data; and determining the fault position of the to-be-detected cable according to the positioning spectrum data. According to the technical scheme provided by the embodiment of the invention, the impedance data is processed by utilizing Chirp-Z transformation, the accurate positioning spectrum data with higher resolution, fewer interference peaks and low data redundancy are obtained, and the positioning of various cable faults can be realized according to the corresponding relationship in the positioning spectrum data.

Description

Technical Field

[0001] The present invention relates to the technical field of fault location, and in particular to a cable fault location method, device, equipment and storage medium. Background Art

[0002] In recent years, rapid urbanization has led to an increasing shortage of urban land, and the safety and environmental concerns of overhead lines have prompted the widespread use of power cables. Compared to overhead lines, cables offer advantages such as smaller footprint, higher power reliability, and greater transmission capacity. However, as cable installations and years of operation increase, cable failure and aging have become key concerns. During actual operation, thermal effects, moisture, sheath damage, and manufacturing process issues can all cause cable aging, leading to failures. Since most cables are laid underground, the inability to quickly and accurately locate the fault point in the event of a failure increases repair time and costs, and can even cause power outages and significant economic losses. Therefore, monitoring and diagnosing the operating status of cables to ensure safe and stable operation is crucial.

[0003] Frequency domain reflectometry (FDR) is an effective method for cable diagnosis and fault location due to its high sensitivity. While traditional FDR can locate cable faults, it suffers from low accuracy and high data redundancy, making it prone to misidentification and omission of fault points. Summary of the Invention

[0004] The present invention provides a cable fault locating method, device, equipment and storage medium to solve the problem of low cable fault locating accuracy.

[0005] In a first aspect, the present invention provides a cable fault location method, comprising:

[0006] Obtain impedance data of the cable to be tested;

[0007] Performing a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, where the target distance is the distance from a point where the impedance data is collected;

[0008] The fault location of the cable to be tested is determined according to the positioning spectrum data.

[0009] In a second aspect, the present invention provides a cable fault locating device, comprising:

[0010] A data acquisition module is used to obtain impedance data of the cable to be tested;

[0011] a data conversion module, configured to perform a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, where the target distance is the distance from a point where the impedance data is collected;

[0012] A fault location determination module is used to determine the fault location of the cable to be tested based on the positioning spectrum data.

[0013] In a third aspect, the present invention provides an electronic device, comprising:

[0014] at least one processor;

[0015] and a memory communicatively coupled to the at least one processor;

[0016] The memory stores a computer program that can be executed by at least one processor. The computer program is executed by at least one processor so that the at least one processor can execute the cable fault location method of the first aspect.

[0017] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer instructions, which are used to enable a processor to implement the cable fault location method of the first aspect when executed.

[0018] The cable fault location solution provided by the present invention obtains impedance data of the cable under test and performs a Chirp-Z transform on the impedance data to obtain location spectrum data. The location spectrum data includes a correspondence between normalized amplitude and target distance, where the target distance is the distance from the point where the impedance data was collected. The fault location of the cable under test is determined based on the location spectrum data. By adopting this technical solution, compared with traditional fault location methods, the Chirp-Z transform is used to process the impedance data, resulting in more accurate location spectrum data with higher resolution, fewer interference peaks, and lower data redundancy. Based on the correspondence in the location spectrum data, various cable faults can be located.

[0019] It should be understood that the content described in this section is not intended to identify the key or important features of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily 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 This is a flow chart of a cable fault location method provided according to the first embodiment of the present invention;

[0022] Figure 2 This is a flow chart of a cable fault location method provided according to the second embodiment of the present invention;

[0023] Figure 3 is a graph of normalized amplitude and target distance provided according to the second embodiment of the present invention;

[0024] Figure 4 This is a structural diagram of a cable fault locating device provided according to a third embodiment of the present invention;

[0025] Figure 5 It is a structural diagram of an electronic device provided according to the fourth embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions 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 embodiments described 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 making creative efforts should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first," "second," and the like in the specification and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than that illustrated or described herein. In the description of the present invention, unless otherwise specified, "plurality" refers to two or more. "And / or" describes an association relationship between associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship. 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 explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0028] The choice of time-frequency conversion method in frequency domain reflectometry is key to achieving high-precision cable positioning. Existing research has explored various methods for frequency-domain to time-domain conversion, such as inverse Fourier transform and integral transforms using different integral kernel functions. Frequency domain reflectometry is based on transmission line theory. A transmission line is part of a circuit, connecting the generator and the load. The performance of a transmission line depends on the ratio of its length to the wavelength λ of the electrical signal entering it. The wavelength λ is expressed as:

[0029] λ=v / f

[0030] Where v is the propagation velocity of the signal in the transmission line (also called phase velocity), and f is the frequency of the signal.

[0031] When the transmission line length is much shorter than the wavelength, such as when the cable is short (e.g., a few meters) and the signal frequency is low (e.g., a few kilohertz), the line has no effect on the circuit's behavior. Thus, the circuit impedance (Z) viewed from the power supply is always equal to the load impedance.

[0032] However, if the line length is longer than the signal wavelength (l ≥ λ), the line characteristics play an important role and the circuit impedance seen from the power supply side does not match that of the load.

[0033] The voltage V and current I on the cable are determined by the following differential equations, which are called telegraph equations:

[0034]

[0035] Where ω is the signal angular frequency, R is the conductor resistance, L is the inductance, C is the capacitance, and G is the insulation conductivity, all of which are related to the cable length unit.

[0036] When a high-frequency signal passes through a cable, these four parameters can fully describe the characteristics of the cable. In transmission line theory, the behavior of a transmission line is usually described as a function of two complex numbers.

[0037] The first is the propagation function:

[0038]

[0039] It can be written as:

[0040] γ=α+jβ

[0041] Where the real part α is the line attenuation constant, and the imaginary part β is the propagation constant, which is related to the phase velocity v, angular frequency ω, and wavelength λ:

[0042]

[0043] The second parameter is the characteristic impedance:

[0044]

[0045] The above formula can be used to solve the telegraph equation, and the line impedance of the cable at a distance d from the end is obtained as:

[0046]

[0047] Among them, Γ d is the generalized reflection coefficient:

[0048] Γ d =Γ L e -2γd

[0049] Γ L is the load reflection coefficient:

[0050]

[0051] Among them, Z L is the load impedance connected at the end of the line.

[0052] From the above formula, we can see that when Γ d =Γ L When =0, Zd=Z0=ZL.

[0053] Existing methods based on transmission line theory attempt to locate local cable faults by measuring the voltage as a function of time in the telegraph equation and evaluating the time delay from the incident wave to the reflected wave. Real-world line attenuation and ambient noise limit their sensitivity, preventing early detection of attenuation, especially for cables exceeding several kilometers in length. This inability to accurately assess global cable condition hinders estimation of remaining cable life in harsh environment applications.

[0054] Example 1

[0055] Figure 1 A flowchart of a cable fault locating method is provided for the first embodiment of the present invention. This embodiment is applicable to situations where cable faults are located. The method can be performed by a cable fault locating device. The cable fault locating device can be implemented in the form of hardware and / or software. The cable fault locating device can be configured in an electronic device. The electronic device can be composed of two or more physical entities or one physical entity.

[0056] like Figure 1 As shown, the cable fault location method provided in the first embodiment of the present invention specifically includes the following steps:

[0057] S101. Obtain impedance data of a cable to be tested.

[0058] In this embodiment, a vector network analyzer can be used to collect the input impedance amplitude and phase spectrum Z(f) to obtain the impedance amplitude spectrum (i.e., impedance data) of the cable. The impedance amplitude spectrum includes the characteristics of the impedance amplitude changing with frequency.

[0059] S102. Perform a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, and the target distance is a distance from a collection point of the impedance data.

[0060] In this embodiment, the traditional method is to use the fast Fourier transform algorithm to process the collected Z(f) and convert the frequency domain data into time domain data. However, since the number of points of the time domain data and the frequency domain data in the fast Fourier transform algorithm is the same, and the transformed data will be evenly distributed across all time domains or frequency domains, most of the information in the time domain data obtained by the traditional method is redundant. This redundant information is not only irrelevant to the cable defect location results, but may also introduce interference peaks, affecting the judgment of the defect location results. On the other hand, the amount of time domain data obtained by the traditional method is also relatively small, resulting in a low resolution of the time domain data curve, which further results in a low sampling rate of the final defect location function, making it easy to cause a fence effect, making it difficult to accurately locate cable defects.

[0061] The Chirp-Z transform, also known as the linear frequency modulation Z transform, can densely compute local spectra and improve local spectral resolution. The key concept behind the Chirp-Z transform is to sample the Z plane at equal intervals along the spiral of the unit circle. Its fundamental principle is to transform discrete signals to obtain the signal's characteristics within a specific frequency range, thereby generating localized spectrum data.

[0062] S103: Determine the fault location of the cable to be tested according to the positioning spectrum data.

[0063] In this embodiment, based on the theory of single-frequency signal windowing, the maximum point in the spectral amplitude of the localization spectrum data occurs at the true frequency. Therefore, at high resolution, the spectral maximum can be identified as the true frequency, and the location corresponding to this maximum is the fault location. Therefore, the location corresponding to the maximum point in the localization spectrum data can be determined as the fault location of the cable under test.

[0064] The cable fault location method provided by an embodiment of the present invention obtains impedance data of the cable under test and performs a Chirp-Z transform on the impedance data to obtain location spectrum data. The location spectrum data includes a correspondence between normalized amplitude and target distance, where the target distance is the distance from the point where the impedance data was collected. The fault location of the cable under test is determined based on the location spectrum data. The technical solution of the embodiment of the present invention uses a Chirp-Z transform to process the impedance data, obtaining accurate location spectrum data with higher resolution, fewer interference peaks, and low data redundancy. Based on the correspondence in the location spectrum data, various cable faults can be located.

[0065] Optionally, performing a Chirp-Z transform on the impedance data to obtain positioning spectrum data includes: performing a Chirp-Z transform on the real part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the real part of the impedance amplitude of the cable to be tested.

[0066] Optionally, performing a Chirp-Z transform on the impedance data to obtain positioning spectrum data includes: performing a Chirp-Z transform on the modulus of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the modulus of the impedance amplitude of the cable to be tested.

[0067] For example, assuming that the impedance data x(n) represents an N-point sequence, 0≤n≤N-1, the Chirp-Z transformation function is:

[0068]

[0069] Where:

[0070] z k =AW -k k=0,1,…,M-1

[0071]

[0072] M is the number of data points after Chirp-Z transformation, A0 is the length of the vector radius of the first x(0), θ0 is the phase angle of the starting sampling point, is the angle difference between adjacent sampling points. Different values represent different directions. Time is counterclockwise, When W0 is greater than 1, the spiral shrinks inwards; when W0 is less than 1, the spiral expands outwards. When W0 is equal to 1, it represents an arc with a radius of A0. If A0 is equal to 1, it represents an arc on the unit circle.

[0073] The function for performing Chirp-Z transform on impedance data can be expressed as:

[0074]

[0075] Where N is the number of data points of the (broadband) impedance data, θ0 is the starting phase, A0 is the starting point position, and W0 is the extension rate of the helix. is the angular frequency difference between two adjacent sampling points.

[0076] Example 2

[0077] Figure 2 This is a flow chart of a cable fault locating method provided in the second embodiment of the present invention. The technical solution of the embodiment of the present invention is further optimized on the basis of the above optional technical solutions, and provides a specific method for locating cable faults.

[0078] Optionally, performing a Chirp-Z transform on the impedance data to obtain positioning spectrum data includes: performing a Chirp-Z transform on the imaginary part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the imaginary part of the impedance amplitude of the cable to be tested.

[0079] Optionally, determining the fault location of the cable to be tested based on the positioning spectrum data includes: determining the peak area data in the positioning spectrum data, and performing FIR filtering on the non-peak area data to obtain filtered data; decomposing the filtered data using a DB2 wavelet basis function to obtain a decomposition result, and denoising the decomposition result using a preset threshold to obtain target data; reconstructing the target data to obtain the denoised positioning spectrum data, and determining the fault location of the cable to be tested based on the denoised positioning spectrum data.

[0080] like Figure 2 As shown, a cable fault location method provided by the second embodiment of the present invention specifically includes the following steps:

[0081] S201. Obtain impedance data of a cable to be tested.

[0082] S202: Perform a Chirp-Z transform on the imaginary part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the imaginary part of the impedance amplitude of the cable to be tested.

[0083] Furthermore, the stretching rate of the spiral in the Chirp-Z transform function is W0=4 -1 / (M*N) ; Where N is the number of impedance data, M = floor((x max -x min ) / Δx), floor() means round down, x max is the preset maximum length of the fault area in the cable to be tested, xmin is the preset minimum length of the fault area in the cable to be tested, and Δx is the preset length resolution.

[0084] Specifically, when using Chirp-Z transform to analyze impedance spectrum data, it is necessary to determine the length range of the cable to be analyzed. Therefore, the maximum value, minimum value and resolution of the length of the fault area can be pre-set as x max 、x min and Δx. In actual testing, the above-mentioned related parameters can be freely selected according to the test results.

[0085] Parameters θ0 in Chirp-Z transform, M can be expressed as:

[0086] θ0=4πx min / (vf s )

[0087]

[0088] M=floor((x max -x min ) / Δx)

[0089] Floor() means round down, f s is the sampling frequency of the impedance data, and v is the velocity of the electromagnetic wave in the cable.

[0090] Under the influence of the attenuation constant, the amplitude of the reflected signal is inversely proportional to the distance of the defect from the head end, which is not conducive to the location analysis of long-distance defects. In the Z transform, W0 can control the extension rate of the transformed spiral. Therefore, by setting W0 < 1, the spiral is set to an extended state, thereby increasing the amplitude of the reflected signal of long-distance defects. The extension rate W0 of the spiral in the Chirp-Z transform can be expressed as:

[0091] W0=4 -1 / (MN)

[0092] S203 , determining peak area data in the positioning spectrum data, and performing FIR filtering on the non-peak area data to obtain filtered data.

[0093] S204 , decomposing the filtered data using a DB2 wavelet basis function to obtain a decomposition result, and denoising the decomposition result using a preset threshold to obtain target data.

[0094] Specifically, due to the complexity and diversity of the causes of cable faults, the degree of impedance mismatch generated is different. The size of the reflected wave is proportional to the degree of impedance mismatch. When the impedance change caused by the fault is relatively weak, the oscillation frequency component contained in the frequency domain reflection coefficient spectrum is too small, resulting in the fault location spectrum after Chirp-Z transform processing being unable to correctly present the fault location. In addition, the high sidelobes generated by the data truncation effect of the Chirp-Z transform are superimposed on the echo signal generated at the fault point, resulting in misjudgment or inability to identify the fault location. Therefore, the Chirp-Z transform has a good effect on locating faults with a large degree of impedance mismatch, but the locating effect for faults with a weak degree of impedance mismatch needs to be improved. To solve the above problems, peak detection and wavelet filtering can be used to denoise the transformation results. The specific process is:

[0095] First, for the positioning spectrum data after Chirp-Z transformation, the threshold method can be used to perform peak detection to extract the peak area data in the positioning spectrum data. Subsequently, FIR (Finite Impulse Response) filtering is performed on the non-peak point part to retain the key peak features to improve the accuracy of signal processing. Then, wavelet filtering is performed on the entire data (i.e., filtered data). For example, the DB2 wavelet basis function is used to decompose the filtered data, and a threshold is set to filter the decomposed wavelet signal. The threshold λ can be determined as follows:

[0096]

[0097] Where σ is the noise standard deviation and Q is the length of the filtered data.

[0098] S205 : reconstruct the target data to obtain noise-reduced positioning spectrum data, and determine the fault location of the cable to be tested according to the noise-reduced positioning spectrum data.

[0099] Specifically, the noise-reduced positioning spectrum data is two-dimensional data, including the noise-reduced normalized amplitude and the corresponding target distance. The position corresponding to a noise-reduced normalized amplitude in the noise-reduced positioning spectrum data can be determined as the fault location of the cable to be tested.

[0100] Furthermore, determining the fault location of the cable to be tested based on the noise-reduced positioning spectrum data includes: performing envelope processing on the noise-reduced positioning spectrum data to obtain a processing result; outputting a graph of normalized amplitude and target distance based on the processing result, and determining the fault location of the cable to be tested based on the target distance corresponding to the peak point in the graph.

[0101] Specifically, the noise-reduced location spectrum data can be subjected to envelope processing, and the results can be saved for further processing and display on external devices or computers. The results can be displayed using data visualization techniques, helping users determine the cable fault location based on the peak value of the normalized amplitude versus target distance spectrum. Envelope processing is a crucial step in signal processing, primarily used to extract the amplitude variation trajectory of the signal, known as the signal envelope.

[0102] Figure 3 It is a graph of normalized amplitude and target distance. Figure 3 Figure 2 is a graph of normalized amplitude versus target distance for a 1000-meter cable. Figure 3 The horizontal axis is the distance, and the vertical axis is the normalized amplitude. Figure 3 The line formed by the red points in the graph is the processing result. The position corresponding to the peak point in the spectrum can be determined as the fault position of the cable to be tested, that is, Figure 3 The points (300.166, 6.23) and (799.44, 8.04) in the figure correspond to the positions of the cables, which indicate that there is a cable fault at the 300-meter position and the 800-meter position respectively.

[0103] Compared with traditional fault location methods, the cable fault location method provided by the embodiment of the present invention uses Chirp-Z transform to process impedance data, which can obtain accurate, higher-resolution, less interference peak and low-redundancy location spectrum data. Peak detection and wavelet filtering are then used to denoise the transformation results, effectively eliminating noise in the reflection coefficient spectrum while preserving the characteristics of the original signal as much as possible, thereby significantly improving the fault location effect.

[0104] Example 3

[0105] Figure 4 This is a schematic diagram of the structure of a cable fault location device provided by the third embodiment of the present invention. Figure 4 As shown, the device includes: a data acquisition module 301, a data transformation module 302 and a fault location determination module 303, wherein:

[0106] A data acquisition module is used to obtain impedance data of the cable to be tested;

[0107] a data conversion module, configured to perform a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, where the target distance is the distance from a point where the impedance data is collected;

[0108] A fault location determination module is used to determine the fault location of the cable to be tested based on the positioning spectrum data.

[0109] The cable fault locating device provided in an embodiment of the present invention uses Chirp-Z transform to process impedance data to obtain accurate positioning spectrum data with higher resolution, fewer interference peaks and low data redundancy. According to the corresponding relationship in the positioning spectrum data, various cable faults can be located.

[0110] Optionally, the data conversion module is specifically used to perform Chirp-Z transformation on the imaginary part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the imaginary part of the impedance amplitude of the cable to be tested.

[0111] Optionally, the data conversion module is specifically configured to perform a Chirp-Z transform on the real part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the real part of the impedance amplitude of the cable to be tested.

[0112] Optionally, the data conversion module is specifically used to perform Chirp-Z transformation on the modulus of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the modulus of the impedance amplitude of the cable to be tested.

[0113] Furthermore, the stretching rate of the spiral in the Chirp-Z transform function is W0=4 -1 / (M*N) ; Where N is the number of impedance data, M = floor((x max -x min ) / Δx), floor() means round down, x max is the preset maximum length of the fault area in the cable to be tested, x min is the preset minimum length of the fault area in the cable to be tested, and Δx is the preset length resolution.

[0114] Optionally, the fault location determination module includes:

[0115] Determining peak area data in the positioning spectrum data, and performing FIR filtering on non-peak area data to obtain filtered data;

[0116] Decomposing the filtered data using a DB2 wavelet basis function to obtain a decomposition result, and denoising the decomposition result using a preset threshold to obtain target data;

[0117] The target data is reconstructed to obtain noise-reduced positioning spectrum data, and the fault position of the cable to be tested is determined according to the noise-reduced positioning spectrum data.

[0118] Furthermore, determining the fault location of the cable to be tested based on the noise-reduced positioning spectrum data includes: performing envelope processing on the noise-reduced positioning spectrum data to obtain a processing result; outputting a graph of normalized amplitude and target distance based on the processing result, and determining the fault location of the cable to be tested based on the target distance corresponding to the peak point in the graph.

[0119] The cable fault locating device provided in the embodiment of the present invention can execute the cable fault locating method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0120] Example 4

[0121] Figure 5 A 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 processing, 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 claimed herein.

[0122] like Figure 5 As shown, the electronic device 40 includes at least one processor 41 and a memory, such as a read-only memory (ROM) 42, a random access memory (RAM) 43, etc., which is communicatively connected to the at least one processor 41. The memory stores a computer program that can be executed by the 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 into the random access memory (RAM) 43. Various programs and data required for the operation of the electronic device 40 can also be stored in the RAM 43. The processor 41, ROM 42, and RAM 43 are connected to each other via a bus 44. An input / output (I / O) interface 45 is also connected to the bus 44.

[0123] Multiple 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 magnetic 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 via a computer network such as the Internet and / or various telecommunication networks.

[0124] Processor 41 can be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of processor 41 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various specialized artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any other suitable processor, controller, microcontroller, etc. Processor 41 executes the various methods and processes described above, such as the cable fault location method.

[0125] In some embodiments, the cable fault location method can be implemented as a computer program tangibly embodied in a computer-readable storage medium, such as storage unit 48. In some embodiments, part or all of the computer program can be loaded and / or installed on electronic device 40 via ROM 42 and / or communication unit 49. When the computer program is loaded into RAM 43 and executed by processor 41, one or more steps of the cable fault location method described above can be performed. Alternatively, in other embodiments, processor 41 can be configured to execute the cable fault location method in any other suitable manner (e.g., via firmware).

[0126] Various embodiments of the systems and techniques described 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), system-on-chip (SOC) systems, complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes 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.

[0127] 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, such that when the computer program is executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer program may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0128] The computer device provided above can be used to execute the cable fault locating method provided in any of the above embodiments, and has corresponding functions and beneficial effects.

[0129] Example 5

[0130] In the context of the present invention, a computer-readable storage medium may be a tangible medium having computer-executable instructions for performing a cable fault location method when executed by a computer processor, the method comprising:

[0131] Obtain impedance data of the cable to be tested;

[0132] Performing a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, where the target distance is the distance from a point where the impedance data is collected;

[0133] The fault location of the cable to be tested is determined according to the positioning spectrum data.

[0134] In the context of the present invention, computer-readable storage medium can be a tangible medium that can contain or store a computer program for use with an instruction execution system, device or equipment or used in conjunction with an instruction execution system, device or equipment. Computer-readable storage medium can 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, computer-readable storage medium can be a machine-readable signal medium. A more specific example of a machine-readable storage medium can 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.

[0135] The computer device provided above can be used to execute the cable fault locating method provided in any of the above embodiments, and has corresponding functions and beneficial effects.

[0136] It is worth noting that in the embodiment of the above-mentioned cable fault locating device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be achieved; in addition, the specific names of the functional units are only for the convenience of distinguishing each other and are not used to limit the scope of protection of the present invention.

[0137] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions are possible for those skilled in the art without departing from the scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A cable fault location method, characterized in that: include: Obtain impedance data of the cable to be tested; Performing a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, where the target distance is the distance from a point where the impedance data is collected; The fault location of the cable to be tested is determined according to the positioning spectrum data.

2. The method according to claim 1, characterized in that The performing Chirp-Z transformation on the impedance data to obtain positioning spectrum data includes: Performing a Chirp-Z transform on the imaginary part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the imaginary part of the impedance amplitude of the cable to be tested.

3. The method according to claim 1, characterized in that The performing Chirp-Z transformation on the impedance data to obtain positioning spectrum data includes: Performing a Chirp-Z transform on the real part of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the real part of the impedance amplitude of the cable to be tested.

4. The method according to claim 1, wherein The performing Chirp-Z transformation on the impedance data to obtain positioning spectrum data includes: A Chirp-Z transform is performed on the modulus of the impedance amplitude of the cable to be tested to obtain positioning spectrum data, wherein the impedance data includes the modulus of the impedance amplitude of the cable to be tested.

5. The method according to any one of claims 1 to 4, characterized in that The stretch rate of the spiral in the Chirp-Z transformation function is W0=4 -1 / (M*N) ; Where N is the number of impedance data, M = floor((x max -x min ) / Δx), floor() means round down, x max is the preset maximum length of the fault area in the cable to be tested, x min is the preset minimum length of the fault area in the cable to be tested, and Δx is the preset length resolution.

6. The method according to claim 1, characterized in that The determining the fault location of the cable to be tested according to the positioning spectrum data includes: Determining peak area data in the positioning spectrum data, and performing FIR filtering on non-peak area data to obtain filtered data; Decomposing the filtered data using a DB2 wavelet basis function to obtain a decomposition result, and denoising the decomposition result using a preset threshold to obtain target data; The target data is reconstructed to obtain noise-reduced positioning spectrum data, and the fault position of the cable to be tested is determined according to the noise-reduced positioning spectrum data.

7. The method according to claim 6, characterized in that The determining the fault location of the cable to be tested according to the noise-reduced positioning spectrum data includes: performing envelope processing on the noise-reduced positioning spectrum data to obtain a processing result; A graph of normalized amplitude and target distance is output according to the processing result, and the fault position of the cable to be tested is determined according to the target distance corresponding to the peak point in the graph.

8. A cable fault locating device, characterized in that: include: A data acquisition module is used to obtain impedance data of the cable to be tested; a data conversion module, configured to perform a Chirp-Z transform on the impedance data to obtain positioning spectrum data, wherein the positioning spectrum data includes a correspondence between a normalized amplitude and a target distance, where the target distance is the distance from a point where the impedance data is collected; A fault location determination module is used to determine the fault location of the cable to be tested based on the positioning spectrum data.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor. The computer program is executed by the at least one processor to enable the at least one processor to perform the cable fault locating method according to any one of claims 1 to 7.

10. 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 cable fault location method according to any one of claims 1 to 7 when executed.

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