A method, apparatus, device, and storage medium for determining fault sections in a cable.

Abstract

This application discloses a method, apparatus, equipment, and storage medium for determining fault sections in cables. It involves collecting the power frequency current and zero-sequence current at each ring main unit (RNB) in the cable under test; preprocessing the power frequency current and zero-sequence current at each RNB to obtain corresponding first and second current signals; analyzing the first and second current signals to determine the current amplitude and polarity at each RNB; determining the location of each RNB in ​​the cable under test; and identifying the fault section based on the current amplitude, polarity, and location at each RNB. This application combines the analysis of power frequency current and zero-sequence current signals to obtain current amplitude and polarity. Based on these two aspects and the location of the RNB, the fault section is accurately determined, eliminating the need for extensive troubleshooting and significantly saving time and resources, thus improving the efficiency of fault section determination.

Description

Technical Field

[0001] This application relates to the field of cable fault section technology, specifically to a method, apparatus, equipment, and storage medium for determining cable fault sections. Background Technology

[0002] In modern power systems and communications, cables play a crucial role as a key transmission medium. With rapid economic development and continuous technological advancements, the demands for stability and reliability in power and communications are constantly increasing. During long-term operation, cables inevitably experience faults due to various internal and external factors. Accurate identification of the faulty section is therefore essential for targeted repair and handling.

[0003] In the commonly used methods for fault section identification, the fault is usually determined by the change in the zero-sequence current amplitude of the cable. However, this method can only roughly determine the possible area of ​​the fault, but cannot accurately determine the fault section. Therefore, a lot of troubleshooting work is required, which wastes time and resources. Summary of the Invention

[0004] In view of this, this application provides a method, apparatus, device and storage medium for determining the fault section of a cable, which solves the problem that existing fault section determination methods can only roughly determine the area where the fault may exist, but cannot accurately determine the fault section, thus requiring a lot of troubleshooting work and wasting time and resources.

[0005] To achieve the above objectives, the following solution is proposed:

[0006] Firstly, a method for determining fault sections in a cable, comprising:

[0007] Collect the power frequency current and zero-sequence current at each ring main unit in the cable line under test;

[0008] For each ring main unit, the power frequency current and zero-sequence current at the ring main unit are preprocessed to obtain the corresponding first current signal and second current signal.

[0009] By combining the first current signal and the second current signal, the current amplitude and current polarity at the ring main unit can be determined.

[0010] Determine the location of each ring main unit in the cable line under test;

[0011] Based on the current amplitude, current polarity, and location at each of the ring main units, the fault section of the cable line under test is determined.

[0012] Preferably, the preprocessing of the power frequency current and zero-sequence current at the ring main unit to obtain the corresponding first current signal and second current signal includes:

[0013] The power frequency current is filtered to obtain a first analog signal;

[0014] The first analog signal is converted to a digital signal to obtain a first current signal;

[0015] The zero-sequence current is filtered to obtain a second analog signal;

[0016] The second analog signal is converted from analog to digital to obtain the second current signal.

[0017] Preferably, the step of analyzing the first current signal and the second current signal to determine the current amplitude and polarity at the ring main unit includes:

[0018] Calculate the average current value of the first current signal;

[0019] Determine the unbalanced current value of the first current signal;

[0020] The imbalance of the first current signal is calculated based on the average current value and the unbalanced current value.

[0021] Determine the changing state of the second current signal;

[0022] Based on the imbalance of the first current signal and the change state of the second current signal, the current amplitude and current polarity at the ring main unit are determined.

[0023] Preferably, determining the current amplitude and polarity at the ring main unit based on the imbalance of the first current signal and the change state of the second current signal includes:

[0024] Determine whether the imbalance is greater than a first preset threshold;

[0025] If so, the current amplitude and current polarity are determined from the changing state of the second current signal;

[0026] If not, then determine the unbalanced position of the first current signal;

[0027] At the unbalanced position, the current amplitude and current polarity of the second current signal are determined.

[0028] Preferably, determining the fault section of the cable line under test based on the current amplitude, current polarity, and location at each of the ring main units includes:

[0029] For each of the aforementioned ring main units, that ring main unit is designated as the target ring main unit;

[0030] Based on the location of the target ring main unit, two ring main units adjacent to the target ring main unit are determined and designated as the upstream ring main unit and the downstream ring main unit, respectively.

[0031] Based on the current amplitude and current polarity of the target ring main unit, the upstream ring main unit, and the downstream ring main unit, the fault section of the cable line under test is determined.

[0032] Preferably, determining the fault section of the cable line under test based on the current amplitude and current polarity of the target ring main unit, the upstream ring main unit, and the downstream ring main unit includes:

[0033] Calculate the difference between the current amplitude of the upstream ring main unit and the current amplitude of the target ring main unit;

[0034] Determine whether the difference is greater than a second preset threshold;

[0035] If the difference is greater than the second preset threshold, it is determined whether the current polarity of the upstream ring main unit is the same as that of the target ring main unit, and at the same time, the current polarity of the target ring main unit is opposite to that of the downstream ring main unit.

[0036] If so, the line section between the target ring main unit and the downstream ring main unit shall be regarded as the fault section of the cable line under test.

[0037] Preferably, after determining the faulty section of the cable line under test, the method further includes:

[0038] Determine the fault type of the faulty section;

[0039] Search the fault type in the pre-acquired fault feature library to determine the fault handling method corresponding to the fault type;

[0040] The faulty section is processed using the aforementioned fault handling method.

[0041] Secondly, a fault section determination device for a cable includes:

[0042] The current acquisition module is used to acquire the power frequency current and zero-sequence current at each ring main unit in the cable line under test;

[0043] The preprocessing module is used to preprocess the power frequency current and zero-sequence current at each ring main unit to obtain the corresponding first current signal and second current signal.

[0044] The analysis module is used to analyze the first current signal and the second current signal to determine the current amplitude and current polarity at the ring main unit.

[0045] The location determination module is used to determine the location of each ring main unit in the cable line under test;

[0046] The fault section determination module is used to determine the fault section of the cable line under test based on the current amplitude, current polarity, and location at each of the ring main units.

[0047] Thirdly, a fault section identification device for a cable includes a memory and a processor;

[0048] The memory is used to store programs;

[0049] The processor is configured to execute the program to implement the various steps of the cable fault section determination method as described in any of the first aspects.

[0050] Fourthly, a storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the cable fault section determination method as described in any of the first aspects.

[0051] As can be seen from the above technical solution, this application collects the power frequency current and zero-sequence current at each ring main unit in the cable line under test; for each ring main unit, the power frequency current and zero-sequence current at that ring main unit are preprocessed to obtain the corresponding first current signal and second current signal; the first current signal and the second current signal are analyzed together to determine the current amplitude and current polarity at that ring main unit; the position of each ring main unit in the cable line under test is determined; based on the current amplitude, current polarity and position of each ring main unit, the fault section of the cable line under test is determined. This application uses the ring main units in the cable line under test as reference points, collects power frequency current and zero-sequence current, and analyzes the current signals to obtain the current amplitude and current polarity. This solves the defect of the prior art of only obtaining the zero-sequence current amplitude. Starting from both the current amplitude and current polarity, and based on the position of the ring main unit, the fault section is accurately determined. This eliminates the need for a large amount of troubleshooting work, greatly saving time and resources and improving the efficiency of fault section judgment. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0053] Figure 1 An optional flowchart of a cable fault section determination method provided in an embodiment of this application;

[0054] Figure 2 This application provides a schematic diagram of a cable line circuit.

[0055] Figure 3 A schematic diagram of a cable fault section determination device provided in an embodiment of this application;

[0056] Figure 4 This is a schematic diagram of a cable fault section determination device provided in an embodiment of this application. Detailed Implementation

[0057] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0058] In modern power systems and communications, cables play a crucial role as a key transmission medium. With rapid economic development and continuous technological advancements, the demands for stability and reliability in power and communications are constantly increasing. During long-term operation, cables inevitably experience faults due to various internal and external factors. Accurate identification of the faulty section is therefore essential for targeted repair and handling.

[0059] In the commonly used methods for fault section identification, the fault is usually determined by the change in the zero-sequence current amplitude of the cable. However, this method can only roughly determine the possible area of ​​the fault, but cannot accurately determine the fault section. Therefore, a lot of troubleshooting work is required, which wastes time and resources.

[0060] In addition, current domestic and international research and application of line grounding fault segmentation can be divided into the following aspects: First, the electrical quantities of voltage and current transformers provided by primary and secondary integrated switchgear are collected, and fault segmentation is achieved by using the transient zero-sequence voltage and current of the fault. This method can only determine the fault section with switch positions and cannot determine the fault section without switch at the branch point. Second, a special device based on the traveling wave ranging method is used to collect the high-frequency transient traveling wave signal of the fault and give the specific fault distance. Due to the complex distribution of branches, overhead-cable hybrids, and loads along the line, the traveling wave signal is attenuated and distorted. At the same time, it is difficult to distinguish between fault and interference signals, resulting in poor practical effect. Third, the impedance method is used to measure the line impedance from the fault point to the detection point, but it gives the electrical distance, which is often inconsistent with the physical distance on site.

[0061] To address the shortcomings of the prior art, this invention provides a method for determining fault sections in cables. This method can be applied to various computer terminals or smart terminals, and its execution entity can be the processor or server of the computer terminal or smart terminal. The flowchart of the method is shown below. Figure 1 As shown, it specifically includes:

[0062] S1: Collect the power frequency current and zero-sequence current at each ring main unit in the cable line under test.

[0063] A ring main unit is an electrical device consisting of a set of power transmission and distribution equipment housed in a metal or non-metal insulated cabinet or assembled into a modular ring network power supply unit. This application utilizes ring main units installed on the cable line under test to determine the fault section, and multiple ring main units are installed on the cable line under test.

[0064] This application can use ring main units as segment nodes to determine which two ring main units form a segment that is a fault segment / section.

[0065] Power frequency current refers to alternating current with a frequency of 50Hz or 60Hz, which is a standard frequency widely used in power systems. Zero-sequence current, on the other hand, occurs in a three-phase four-wire circuit when the phasor sum of the three-phase currents is not zero. Under normal circumstances, the phasor sum of the three-phase currents is zero. However, when an imbalance occurs in the circuit, such as a ground fault or an unbalanced three-phase load, the phasor sum of the three-phase currents is no longer zero, resulting in zero-sequence current. Therefore, zero-sequence current can be used as a basis for determining whether a cable line has a fault.

[0066] There is a certain relationship between power frequency current and zero-sequence current. Under normal three-phase balanced load conditions, power frequency current will not generate zero-sequence current. Zero-sequence current may only be generated when three-phase imbalance, ground fault, or other special circumstances occur.

[0067] This application simultaneously acquires the power frequency current and zero-sequence current at each ring main unit for judgment, which can improve the accuracy of fault section judgment compared to relying solely on zero-sequence current.

[0068] S2: For each ring main unit, the power frequency current and zero-sequence current at the ring main unit are preprocessed to obtain the corresponding first current signal and second current signal.

[0069] After obtaining the power frequency current and zero-sequence current, preprocessing can be performed separately, such as filtering, analog-to-digital conversion, and noise reduction, to make the power frequency current signal and zero-sequence current signal clearer, more accurate, and highlight the characteristics of the current signal. Feature extraction can also be performed to extract current signals with obvious feature points for subsequent judgment.

[0070] After preprocessing, a first current signal corresponding to the power frequency current and a second current signal corresponding to the zero-sequence current are obtained.

[0071] S3: Combine the first current signal and the second current signal for analysis to determine the current amplitude and current polarity at the ring main unit.

[0072] By combining the first current signal and the second current signal for analysis, the current amplitude and current polarity at the ring main unit can be calculated.

[0073] The amplitude of the first / second current signal refers to the magnitude of the current, used to represent the intensity of the current. For alternating current, the amplitude usually refers to the peak value or maximum value of the current. Polarity indicates the direction of the current. In a DC circuit, the current flows from a high potential to a low potential, and one direction is defined as the positive direction. Currents in the same direction as the positive direction are positive polarity, and those in the opposite direction are negative polarity. In an AC circuit, although the direction of the current changes continuously over time, the instantaneous polarity of the current is determined based on a reference direction when analyzing certain complex circuits or specific problems.

[0074] S4: Determine the location of each ring main unit in the cable line under test.

[0075] Since this application requires the location of each ring main unit in the cable under test to determine the section, it is also necessary to obtain location information, such as determining which two adjacent ring main units form the section that is faulty.

[0076] Considering that the cable lines under test are generally long and the cross-sectional areas and materials of the multiple cable sections are inconsistent, which affects the judgment results, this application only considers the location of the ring main unit in the cable under test, and combines the power frequency current and zero sequence current to make an accurate judgment.

[0077] S5: Based on the current amplitude, current polarity, and location at each of the ring main units, determine the fault section of the cable line under test.

[0078] The current amplitude and polarity at the ring main unit can be calculated based on the first current signal and the second current signal. For example, the third current signal can be calculated based on the three-phase current composite vector of the first current signal and the composite vector of the second current signal. The amplitude and polarity of the third current signal are the current amplitude and polarity at the ring main unit.

[0079] Alternatively, the transient zero-sequence current corresponding to the second current signal and the location of the ring main unit can be used as the main basis for judgment, with the first current signal as an auxiliary, to determine the fault section of the cable line under test.

[0080] As can be seen from the above technical solution, this application collects the power frequency current and zero-sequence current at each ring main unit in the cable line under test; for each ring main unit, the power frequency current and zero-sequence current at that ring main unit are preprocessed to obtain the corresponding first current signal and second current signal; the first current signal and the second current signal are analyzed together to determine the current amplitude and current polarity at that ring main unit; the position of each ring main unit in the cable line under test is determined; based on the current amplitude, current polarity and position of each ring main unit, the fault section of the cable line under test is determined. This application uses the ring main units in the cable line under test as reference points, collects power frequency current and zero-sequence current, and analyzes the current signals to obtain the current amplitude and current polarity. This solves the defect of the prior art of only obtaining the zero-sequence current amplitude. Starting from both the current amplitude and current polarity, and based on the position of the ring main unit, the fault section is accurately determined. This eliminates the need for a large amount of troubleshooting work, greatly saving time and resources and improving the efficiency of fault section judgment.

[0081] In addition, existing technologies use detection equipment to detect and determine the fault status of each critical node in a cable line. However, there are many critical nodes in a cable line, and many lines involve the installation of monitoring equipment. Therefore, the demand for detection equipment is large and the cost is high. This application can also solve this problem well.

[0082] The method provided in this embodiment of the invention involves preprocessing the power frequency current and zero-sequence current at the ring main unit to obtain the corresponding first current signal and second current signal, as detailed below:

[0083] The power frequency current is filtered to obtain a first analog signal;

[0084] The first analog signal is converted to a digital signal to obtain a first current signal;

[0085] The zero-sequence current is filtered to obtain a second analog signal;

[0086] The second analog signal is converted from analog to digital to obtain the second current signal.

[0087] Specifically, filtering can remove interference components from current signals, improving their accuracy. In some cases, complex noise or interference signals may also be present; filtering allows for better identification of faulty sections using the current signal. On one hand, for complex circuits such as mixed lines and T-connections in the cable under test, the zero-sequence current signal attenuates significantly after a fault, making it difficult to distinguish from interference signals. On the other hand, the voltage level of the cable under test is relatively low, resulting in a smaller amplitude of the zero-sequence current signal. In some cases, if the fault in the cable under test is a high-resistance grounding fault caused by water ingress at the joint, and it is often a non-effectively grounded system, the amplitude of the zero-sequence current signal will also be relatively small, making it difficult to identify. Therefore, filtering can facilitate differentiation and prevent the introduction of errors.

[0088] Analog-to-digital conversion converts analog signals into digital signals, which are then recognized by computers. This allows the calculation of the current amplitude and polarity at the ring main unit based on the first and second current signals obtained.

[0089] The following describes the process of analyzing the first and second current signals in this application to determine the current amplitude and polarity at the ring main unit.

[0090] Calculate the average current value of the first current signal;

[0091] Determine the unbalanced current value of the first current signal;

[0092] The imbalance of the first current signal is calculated based on the average current value and the unbalanced current value.

[0093] Determine the changing state of the second current signal;

[0094] Based on the imbalance of the first current signal and the change state of the second current signal, the current amplitude and current polarity at the ring main unit are determined.

[0095] Specifically, the three-phase currents in the first current signal can be extracted and designated as current 1, current 2 and current 3 respectively. Then, the average value of the three can be calculated as the average current value of the first current signal. The unbalanced current value refers to the phase current with the largest deviation from the average current value among the three-phase currents, which is taken as the comparison current. The difference between the comparison current and the average current value is calculated and the difference is taken as the unbalanced current value.

[0096] Next, we will focus on the zero-sequence current. Therefore, we will use the second current signal corresponding to the zero-sequence current as the main criterion to determine the changing state of the second current signal. Based on the imbalance of the first current signal and the changing state of the second current signal, we will determine the current amplitude and polarity at the ring main unit. The specific process may include:

[0097] Determine whether the imbalance is greater than a first preset threshold;

[0098] If so, the current amplitude and current polarity are determined from the changing state of the second current signal;

[0099] If not, then determine the unbalanced position of the first current signal;

[0100] At the unbalanced position, the current amplitude and current polarity of the second current signal are determined.

[0101] If the imbalance exceeds the first preset threshold, it indicates a large zero-sequence current, suggesting a high probability of a fault in the cable under test. Therefore, the current amplitude and polarity can be determined from the changes in the second current signal, such as by extracting the transient zero-sequence current and determining its amplitude and polarity. If the imbalance is not greater than the first preset threshold, the amplitude and polarity need to be determined intuitively from the imbalance location (i.e., the phase current with the largest deviation from the average current value among the three phase currents at the ring main unit). This case-by-case approach improves accuracy and reduces omissions and errors in judgment.

[0102] The following embodiments provide a detailed description of the steps in this application for determining the fault section of the cable line under test based on the current amplitude, current polarity, and location at each ring main unit.

[0103] For each of the aforementioned ring main units, that ring main unit is designated as the target ring main unit;

[0104] Based on the location of the target ring main unit, two ring main units adjacent to the target ring main unit are determined and designated as the upstream ring main unit and the downstream ring main unit, respectively.

[0105] Based on the current amplitude and current polarity of the target ring main unit, the upstream ring main unit, and the downstream ring main unit, the fault section of the cable line under test is determined.

[0106] The process of determining the fault section of the cable line under test based on the current amplitude and current polarity of the target ring main unit, the upstream ring main unit, and the downstream ring main unit may include:

[0107] Calculate the difference between the current amplitude of the upstream ring main unit and the current amplitude of the target ring main unit;

[0108] Determine whether the difference is greater than a second preset threshold;

[0109] If the difference is greater than the second preset threshold, it is determined whether the current polarity of the upstream ring main unit is the same as that of the target ring main unit, and at the same time, the current polarity of the target ring main unit is opposite to that of the downstream ring main unit.

[0110] If so, the line section between the target ring main unit and the downstream ring main unit shall be regarded as the fault section of the cable line under test.

[0111] Specifically, this application uses the amplitude and polarity between two adjacent ring main units for precise judgment, which can narrow down the fault section in the cable line under test. To ensure accuracy, another adjacent ring main unit is also included in the judgment process, such as... Figure 2 As shown, Figure 2 This is a circuit diagram corresponding to a cable line under test. Ring main unit 1, ring main unit 2, and ring main unit 3 are three adjacent ring main units. Specifically, ring main unit 1 and ring main unit 2 are adjacent, and ring main unit 2 is also adjacent to ring main unit 3. In one example:

[0112] Using ring main unit 1 as the upstream ring main unit, ring main unit 2 as the target ring main unit, and ring main unit 3 as the downstream ring main unit, if the current difference between ring main unit 1 and ring main unit 2 is large, exceeding the second preset threshold, it indicates that the current at ring main unit 1 changed during or midway through the process of passing through ring main unit 2. In this case, it can be roughly considered that a fault has occurred. However, looking only at the current change is not accurate enough. It is also necessary to determine whether the current polarity at ring main unit 3 has changed, that is, whether the current polarity at ring main unit 3 is opposite to that at ring main unit 2. This dual judgment can determine that the section composed of ring main units 2 and 3 has a fault. Therefore, this section is regarded as the fault section of the cable line under test.

[0113] Furthermore, after determining the faulty section of the cable line under test, this method may further include:

[0114] Determine the fault type of the faulty section;

[0115] Search the fault type in the pre-acquired fault feature library to determine the fault handling method corresponding to the fault type;

[0116] The faulty section is processed using the aforementioned fault handling method.

[0117] Specifically, the fault type of the faulty section can also be determined, such as single-phase grounding fault, two-phase short-circuit fault, three-phase short-circuit fault, etc. This makes it easier to handle the fault accordingly. The fault type can be searched from a pre-acquired fault feature library, which contains fault handling methods corresponding to various fault types. Handling the faulty section with the corresponding fault handling method can solve the fault problem accurately and efficiently.

[0118] This application also provides a cable fault section determination system, the system comprising:

[0119] Current sensor, power supply module, communication module, signal processing module.

[0120] The current sensor is used to collect the power frequency current and zero-sequence current at each ring main unit in the cable line under test; the power module controls the power input and battery connection of the system; the communication module can upload the power frequency current and zero-sequence current collected by the current sensor to the signal processing module via a 4G / 5G wireless network; the signal processing module preprocesses the power frequency current and zero-sequence current at each ring main unit to obtain the corresponding first current signal and second current signal, and analyzes the first current signal and second current signal to determine the current amplitude and current polarity at the ring main unit, determine the position of each ring main unit in the cable line under test, and determine the fault section of the cable line under test based on the current amplitude, current polarity and position at each ring main unit.

[0121] Furthermore, the signal processing module can send the faulty section to the backend server, which can then push alarm SMS messages for the faulty section to maintenance personnel. For example, it can interact with the maintenance personnel's mobile phone system backend in real time, making it convenient for maintenance personnel to receive information promptly and handle it quickly.

[0122] This system enables remote control, reduces on-site manual operation, is easy to install, can be networked in a local area network, and can identify fault segments in wide-area cable lines.

[0123] and Figure 1 Corresponding to the method described above, embodiments of the present invention also provide a cable fault section determination device for determining the fault section of a cable. Figure 1 In a specific implementation of the method, the cable fault section judgment device provided in this embodiment of the invention can be used in a computer terminal or various mobile devices, combined with... Figure 3 The document introduces a device for determining the fault section of a cable, such as... Figure 3 As shown, the device may include:

[0124] The current acquisition module 10 is used to acquire the power frequency current and zero-sequence current at each ring network cabinet in the cable line under test.

[0125] The preprocessing module 20 is used to preprocess the power frequency current and zero-sequence current at each ring main unit to obtain the corresponding first current signal and second current signal.

[0126] Analysis module 30 is used to analyze the first current signal and the second current signal to determine the current amplitude and current polarity at the ring main unit.

[0127] The location determination module 40 is used to determine the location of each ring network cabinet in the cable line under test;

[0128] The fault section judgment module 50 is used to determine the fault section of the cable line under test based on the current amplitude, current polarity and location at each of the ring main units.

[0129] As can be seen from the above technical solution, this application collects the power frequency current and zero-sequence current at each ring main unit in the cable line under test; for each ring main unit, the power frequency current and zero-sequence current at that ring main unit are preprocessed to obtain the corresponding first current signal and second current signal; the first current signal and the second current signal are analyzed together to determine the current amplitude and current polarity at that ring main unit; the position of each ring main unit in the cable line under test is determined; based on the current amplitude, current polarity and position of each ring main unit, the fault section of the cable line under test is determined. This application uses the ring main units in the cable line under test as reference points, collects power frequency current and zero-sequence current, and analyzes the current signals to obtain the current amplitude and current polarity. This solves the defect of the prior art of only obtaining the zero-sequence current amplitude. Starting from both the current amplitude and current polarity, and based on the position of the ring main unit, the fault section is accurately determined. This eliminates the need for a large amount of troubleshooting work, greatly saving time and resources and improving the efficiency of fault section judgment.

[0130] Furthermore, embodiments of this application provide a cable fault section determination device. Optionally, Figure 4 The hardware structure block diagram of the cable fault section identification device is shown below. (Refer to...) Figure 4 The hardware structure of the cable fault section determination device may include: at least one processor 01, at least one communication interface 02, at least one memory 03 and at least one communication bus 04.

[0131] In this embodiment, the number of processor 01, communication interface 02, memory 03 and communication bus 04 is at least one, and processor 01, communication interface 02 and memory 03 communicate with each other through communication bus 04.

[0132] Processor 01 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0133] Memory 03 may include high-speed RAM, and may also include non-volatile memory, such as at least one disk storage device.

[0134] The memory stores a program that the processor can call. The program is used to execute the following cable fault section determination method, including:

[0135] Collect the power frequency current and zero-sequence current at each ring main unit in the cable line under test;

[0136] For each ring main unit, the power frequency current and zero-sequence current at the ring main unit are preprocessed to obtain the corresponding first current signal and second current signal.

[0137] By combining the first current signal and the second current signal, the current amplitude and current polarity at the ring main unit can be determined.

[0138] Determine the location of each ring main unit in the cable line under test;

[0139] Based on the current amplitude, current polarity, and location at each of the ring main units, the fault section of the cable line under test is determined.

[0140] Optionally, the refined and extended functions of the program can be found in the description of the cable fault section judgment method in the method embodiment.

[0141] This application embodiment also provides a storage medium that can store a program suitable for execution by a processor. When the program runs, it controls the device where the storage medium is located to execute the following cable fault section determination method, including:

[0142] Collect the power frequency current and zero-sequence current at each ring main unit in the cable line under test;

[0143] For each ring main unit, the power frequency current and zero-sequence current at the ring main unit are preprocessed to obtain the corresponding first current signal and second current signal.

[0144] By combining the first current signal and the second current signal, the current amplitude and current polarity at the ring main unit can be determined.

[0145] Determine the location of each ring main unit in the cable line under test;

[0146] Based on the current amplitude, current polarity, and location at each of the ring main units, the fault section of the cable line under test is determined.

[0147] Specifically, the storage medium can be a computer-readable storage medium, which can be an electronic storage device such as flash memory, EEPROM (Electrically Erasable Programmable Read-Only Memory), EPROM, hard disk, or ROM.

[0148] Optionally, the refined and extended functions of the program can be found in the description of the cable fault section judgment method in the method embodiment.

[0149] Furthermore, the functional modules in the various embodiments of this disclosure can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part. If the function is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this disclosure, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a live streaming device, or a network device, etc.) to execute all or part of the steps of the methods in the various embodiments of this disclosure.

[0150] Finally, 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.

[0151] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0152] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for determining the fault section of a cable, characterized in that, include: Collect the power frequency current and zero-sequence current at each ring main unit in the cable line under test; For each ring main unit, the power frequency current and zero-sequence current at the ring main unit are preprocessed to obtain the corresponding first current signal and second current signal. The analysis combines the first current signal and the second current signal to determine the current amplitude and polarity at the ring main unit; this includes: calculating the average current value of the first current signal; determining the unbalanced current value of the first current signal; calculating the degree of imbalance of the first current signal based on the average current value and the unbalanced current value; determining the change state of the second current signal; and determining the current amplitude and polarity at the ring main unit based on the degree of imbalance of the first current signal and the change state of the second current signal. Determine the location of each ring main unit in the cable line under test; Based on the current amplitude, current polarity, and location at each of the ring main units, the fault section of the cable line under test is determined.

2. The method according to claim 1, characterized in that, The preprocessing of the power frequency current and zero-sequence current at the ring main unit to obtain the corresponding first current signal and second current signal includes: The power frequency current is filtered to obtain a first analog signal; The first analog signal is converted to a digital signal to obtain a first current signal; The zero-sequence current is filtered to obtain a second analog signal; The second analog signal is converted from analog to digital to obtain the second current signal.

3. The method according to claim 1, characterized in that, The determination of the current amplitude and polarity at the ring main unit based on the imbalance of the first current signal and the change state of the second current signal includes: Determine whether the imbalance is greater than a first preset threshold; If so, the current amplitude and current polarity are determined from the changing state of the second current signal; If not, then determine the unbalanced position of the first current signal; At the unbalanced position, the current amplitude and current polarity of the second current signal are determined.

4. The method according to claim 1, characterized in that, The process of determining the fault section of the cable line under test based on the current amplitude, current polarity, and location at each ring main unit includes: For each of the aforementioned ring main units, that ring main unit is designated as the target ring main unit; Based on the location of the target ring main unit, two ring main units adjacent to the target ring main unit are determined and designated as the upstream ring main unit and the downstream ring main unit, respectively. Based on the current amplitude and current polarity of the target ring main unit, the upstream ring main unit, and the downstream ring main unit, the fault section of the cable line under test is determined.

5. The method according to claim 4, characterized in that, The step of determining the fault section of the cable line under test based on the current amplitude and current polarity of the target ring main unit, the upstream ring main unit, and the downstream ring main unit includes: Calculate the difference between the current amplitude of the upstream ring main unit and the current amplitude of the target ring main unit; Determine whether the difference is greater than a second preset threshold; If the difference is greater than the second preset threshold, it is determined whether the current polarity of the upstream ring main unit is the same as that of the target ring main unit, and at the same time, the current polarity of the target ring main unit is opposite to that of the downstream ring main unit. If so, the line section between the target ring main unit and the downstream ring main unit shall be regarded as the fault section of the cable line under test.

6. The method according to claim 1, characterized in that, After determining the faulty section of the cable line under test, the method further includes: Determine the fault type of the faulty section; Search the fault type in the pre-acquired fault feature library to determine the fault handling method corresponding to the fault type; The faulty section is processed using the aforementioned fault handling method.

7. A device for determining the fault section of a cable, characterized in that, include: The current acquisition module is used to acquire the power frequency current and zero-sequence current at each ring main unit in the cable line under test; The preprocessing module is used to preprocess the power frequency current and zero-sequence current at each ring main unit to obtain the corresponding first current signal and second current signal. The analysis module is used to analyze the first current signal and the second current signal to determine the current amplitude and current polarity at the ring main unit; including: calculating the average current value of the first current signal; determining the unbalanced current value of the first current signal; calculating the degree of imbalance of the first current signal based on the average current value and the unbalanced current value; determining the change state of the second current signal; and determining the current amplitude and current polarity at the ring main unit based on the degree of imbalance of the first current signal and the change state of the second current signal. The location determination module is used to determine the location of each ring main unit in the cable line under test; The fault section determination module is used to determine the fault section of the cable line under test based on the current amplitude, current polarity, and location at each of the ring main units.

8. A fault section determination device for cables, characterized in that, Including memory and processor; The memory is used to store programs; The processor is used to execute the program to implement each step of the cable fault section judgment method as described in any one of claims 1-6.

9. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements each step of the cable fault section determination method as described in any one of claims 1-6.

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