A method for detecting defects in intermediate joints of high-voltage cables

Abstract

The present invention provides a method for detecting defects in an intermediate joint of a high-voltage cable, and relates to the technical field of cable installation detection. A defect database is built and an abnormal discharge signal is received. Field restoration of a target area space is performed to obtain a field space. A compensation discharge signal is output in combination with an attenuation compensation model, and penetration loss compensation and defect identification are performed to obtain a defect identification result. The cable transmission loss is analyzed to determine a conductivity detection result, and the technical problem that the technical limitations of the prior art lead to the inability to meet detection requirements, insufficient detection completeness, and inaccurate final detection results, resulting in technical problems such as limited subsequent defect operation and maintenance, insulation breakdown detection is performed based on a partial discharge method, and signal attenuation is eliminated based on field compensation and obstacle compensation to ensure consistency between a received signal and a target discharge signal, thereby improving detection accuracy. Differential analysis of the endpoints of cable transmission is performed to determine the conductivity loss, and the two are combined to ensure detection completeness.

Description

Technical Field

[0001] The invention relates to the technical field of cable installation detection, and in particular to a method for detecting defects in an intermediate joint of a high-voltage cable. Background Art

[0002] As a cable accessory for continuous connection of laid cables, cable intermediate joints can make the cable power supply line smooth and ensure the insulation at the cable joints. At the same time, the installation and real-time connection status of high-voltage cable intermediate joints affect the reliable and stable operation of the cable.

[0003] At present, the detection of cable intermediate joints is mainly based on ultrasonic probes or partial discharge detection. Since the ultrasonic probe needs to contact the outer surface of the cable joint, the detection conditions are high and the detection is difficult. There is signal attenuation in the partial discharge signal detection. The technical limitations of the existing technology make it impossible to meet the detection needs, the detection completeness is insufficient, and the final detection results are not accurate enough, which limits the subsequent defect operation and maintenance. Summary of the invention

[0004] The present application provides a method for detecting defects in intermediate joints of high-voltage cables, which is used to solve the technical problems existing in the prior art that lead to the inability to meet detection requirements, insufficient detection completeness and inaccurate final detection results, resulting in limited subsequent defect operation and maintenance.

[0005] In view of the above problems, the present application provides a method for detecting defects in intermediate joints of high-voltage cables.

[0006] In a first aspect, the present application provides a method for detecting defects in an intermediate joint of a high-voltage cable, the method comprising:

[0007] Build a defect database based on the intermediate joint type and cable installation status;

[0008] Locate the installation position of the middle joint of the cable in the target area, and receive the abnormal discharge signal of the partial discharge, wherein the abnormal discharge signal carries a signal source identifier;

[0009] Perform spatial field restoration on the target area to be detected to obtain a field space, where the field space is a fitting field based on the environmental field, the magnetic field and the electric field;

[0010] Inputting the abnormal discharge signal into an attenuation compensation model and outputting a compensation discharge signal, wherein the attenuation compensation model is embedded with the field space;

[0011] Performing penetration loss compensation on the compensation discharge signal, inputting the signal into a defect recognition model, and outputting a defect recognition result, wherein the defect recognition model is embedded with the defect database;

[0012] Based on the installation position of the intermediate joint of the cable in the target area, performing cable transmission loss analysis of the electrical signal to determine the conductivity test result;

[0013] Based on the conductivity detection result and the defect identification result, a plurality of groups of defect sequences are determined as defect detection results.

[0014] In a second aspect, the present application provides a system for detecting defects in an intermediate joint of a high-voltage cable, the system comprising:

[0015] A database building module, the database building module is used to build a defect database based on the intermediate joint type and the cable installation status;

[0016] A signal receiving module, the signal receiving module is used to locate the installation position of the middle joint of the cable in the target area, and receive the abnormal discharge signal of the partial discharge, the abnormal discharge signal carries a signal source identifier;

[0017] A field space acquisition module, which is used to perform spatial field restoration on the target area to be detected and acquire the field space, wherein the field space is a fitting field based on the environmental field, the magnetic field and the electric field;

[0018] An attenuation compensation module, the attenuation compensation module is used to input the abnormal discharge signal into an attenuation compensation model and output a compensated discharge signal, the attenuation compensation model is embedded with the field space;

[0019] A defect pair recognition module, the defect recognition module is used for performing penetration loss compensation on the compensation discharge signal, inputting into a defect recognition model, and outputting a defect recognition result, wherein the defect recognition model is embedded with the defect database;

[0020] A continuity detection module, the continuity detection module is used to perform cable transmission loss analysis of electrical signals based on the installation position of the middle joint of the cable in the target area, and determine the continuity detection result;

[0021] A result acquisition module is used to determine a plurality of defect sequences as defect detection results based on the conductivity detection result and the defect identification result.

[0022] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0023] A method for detecting defects in intermediate joints of high-voltage cables provided in an embodiment of the present application includes building a defect database based on the type of intermediate joints and the installation status of the cable; locating the installation position of the intermediate joints of the cables in the target area, receiving abnormal discharge signals of partial discharge, performing spatial field restoration on the target area to be detected, and acquiring the field space, that is, the fitting field based on the environmental field, the magnetic field and the electric field, inputting the abnormal discharge signal into an attenuation compensation model, outputting the compensated discharge signal and performing penetration loss compensation, inputting the signal into a defect recognition model, outputting the defect recognition result, and performing cable transmission loss analysis of the electrical signal based on the installation position of the intermediate joints of the cables in the target area. The conductivity test result is determined by analysis; based on the conductivity test result and the defect identification result, multiple groups of defect sequences are determined as defect detection results, which solves the technical problems existing in the prior art that the detection requirements cannot be met, the detection completeness is insufficient and the final detection result is not accurate enough, resulting in technical problems such as limited subsequent defect operation and maintenance. Insulation breakdown detection is performed based on partial discharge, and signal attenuation is eliminated based on field compensation and obstacle compensation to ensure the consistency of the received signal and the target discharge signal, thereby improving the detection accuracy; differential analysis of the cable transmission endpoints is performed to determine the conduction loss, and the two are combined to ensure the completeness of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic flow chart of a method for defect detection of intermediate joints in high-voltage cables is provided for the present application.

[0025] Figure 2 A schematic diagram of a field space acquisition process in a method for detecting defects in intermediate joints of high-voltage cables is provided for this application.

[0026] Figure 3 The present application provides a schematic diagram of a flow chart of obtaining the conductivity test results in a method for detecting defects in an intermediate joint of a high-voltage cable.

[0027] Figure 4 A schematic diagram of a system structure for defect detection of intermediate joints in high-voltage cables is provided for this application.

[0028] Explanation of the reference numerals: database building module 11 , signal receiving module 12 , field space acquisition module 13 , attenuation compensation module 14 , defect identification module 15 , conductivity detection module 16 , result acquisition module 17 . DETAILED DESCRIPTION

[0029] The present application provides a method for defect detection of intermediate joints of high-voltage cables, builds a defect database, receives abnormal discharge signals based on the installation position of the intermediate joint, performs spatial field restoration of the target area to obtain the field space, performs abnormal discharge analysis in combination with an attenuation compensation model, outputs a compensated discharge signal and performs penetration loss compensation, analyzes and outputs defect identification results, performs cable transmission loss analysis of electrical signals to determine conductivity detection results, and determines defect detection results in combination with defect identification results. The application is used to solve the technical problems that the technical limitations of the prior art lead to the inability to meet detection requirements, insufficient detection completeness and inaccurate final detection results, resulting in subsequent defect operation and maintenance being limited.

[0030] Embodiment 1

[0031] like Figure 1 As shown, the present application provides a method for detecting defects in an intermediate joint of a high-voltage cable, the method comprising:

[0032] Step S100: Building a defect database based on the intermediate joint type and the cable installation status;

[0033] Specifically, the cable intermediate joint, as a cable accessory for laying cables for continuous connection, can make the cable power supply line smooth and ensure the insulation at the cable joint. At the same time, the installation and real-time connection status of the high-voltage cable intermediate joint affect the reliable and stable operation of the cable. The present application provides a method for defect detection of the high-voltage cable intermediate joint, which performs insulation breakdown detection and conductivity detection to determine the real-time connection and disconnection status of the high-voltage cable intermediate joint for defect detection, and compensates and restores the transmission attenuation of the detection signal to ensure the consistency of the received signal and the target discharge signal, thereby improving the detection accuracy.

[0034] Specifically, the intermediate joint types include straight-through intermediate joints and bend-through intermediate joints, and the corresponding structures and installation methods are different. The cable sections are connected into a whole based on the intermediate joints. Based on the distribution of the cables, there are single-line connections and multi-line connections, namely one-to-one connections, one-to-many connections and many-to-many connections, which are used as the cable installation status. There are differences in the standards for determining the defect level and status under different intermediate joint types and the cable installation status. Based on the different corresponding relationships between the intermediate joint types and the cable installation status, the existing defect information is retrieved respectively, including the defect source, defect type and defect level, and the retrieved information is called and integrated to generate the defect database, which is a reference for defect identification.

[0035] Step S200: locating the installation position of the middle joint of the cable in the target area, and receiving an abnormal discharge signal of partial discharge, wherein the abnormal discharge signal carries a signal source identifier;

[0036] Specifically, the intermediate joint has a certain insulation level. When there are abnormal conditions such as insulation damage, partial discharge will occur, that is, due to insulation breakdown, signal energy such as electric pulses and electromagnetic radiation will be generated. Defect identification is performed by detecting and receiving the generated partial discharge information. The target area cable is a distribution cable area to be defect-detected. The installation position of the intermediate joint of the target area cable is located, for example, it can be directly identified and located based on the cable distribution map, and partial discharge signal detection is performed, for example, based on the signal receiving probe installed at the predetermined position. If a partial discharge signal is detected, it indicates that there is insulation breakdown. The received signal is used as the abnormal discharge signal, and the discharge source is determined, that is, the intermediate joint and installation position where partial discharge exists, as the signal source identifier. The abnormal discharge signal is the signal source for determining insulation breakdown damage.

[0037] Step S300: performing spatial field restoration on the target area to be detected to obtain a field space, where the field space is a fitting field based on the environmental field, the magnetic field and the electric field;

[0038] Furthermore, if Figure 2 As shown, the spatial field restoration is performed on the target area to be detected to obtain the field space. Step S300 of the present application also includes:

[0039] Step S310: Perform field monitoring on the target area and store the data in a field database, wherein the field database has timeliness and updateability;

[0040] Step S320: extracting field information of a predetermined time sequence based on the field database, wherein the field information includes environmental field information, magnetic field information, and electric field information;

[0041] Step S330: performing field restoration based on the environmental field information, the magnetic field information and the electric field information to obtain a multivariate field;

[0042] Step S340: performing spatial fitting on the multivariate field to generate the field space.

[0043] Specifically, due to the strong attenuation characteristics of the abnormal signal, there is a certain deviation between the signal received by the signal receiving probe and the actual breakdown discharge signal. However, due to the great difficulty of direct contact detection, the accuracy of the abnormal discharge signal can be improved by compensating the received signal to reduce the degree of signal attenuation. The environmental field, magnetic field and electric field information of the target area to be detected are monitored. The environmental field, magnetic field and electric field caused by noise, temperature, etc. will affect the attenuation to a certain extent, and the field influence is compensated. The monitored environmental field distribution information, magnetic field distribution information and electric field distribution information are stored in the field database, that is, the storage repository of field monitoring information, for example, it can be based on uniformly distributed multi-type sensors for perception and collection. Since the distribution of environmental field, electric field and magnetic field is not a fixed field and is in a real-time changing state, the field database is updated in real-time fluctuations to ensure the validity of the field database.

[0044] Furthermore, based on the field database, the environmental field information, the magnetic field information and the electric field information are extracted for a predetermined time sequence, i.e., the time point at which the abnormal discharge signal is spatially transmitted, as the field information. Based on the environmental field information, the environmental field is distributed and restored, which can assist the adaptation device in restoring the spatial distribution of noise, temperature, etc., and simultaneously restore the spatial distribution based on the magnetic field information and the electric field information, for example, based on a magnetic generator, etc., the restored environmental field, magnetic field and electric field are used as the multivariate field. Furthermore, multiple fitting points are determined, i.e., uniformly distributed points in the field, and overlapping fitting is performed on the multivariate field to generate the field space, which has actual compatibility, and field attenuation analysis and compensation are performed in the field space.

[0045] Step S400: inputting the abnormal discharge signal into an attenuation compensation model, and outputting a compensated discharge signal, wherein the attenuation compensation model is embedded with the field space;

[0046] Furthermore, to construct an attenuation compensation model, step S400 of the present application further includes:

[0047] Step S410: calling a first sample discharge signal and a second sample discharge signal, wherein the first sample discharge signal and the second sample discharge signal are mapped correspondingly and have different signal transmission distances;

[0048] Step S420: constructing an attenuation compensation model framework and embedding it into the field space, wherein the field database is connected to the attenuation compensation model for updating the field space;

[0049] Step S430: Based on the first sample discharge signal and the second sample discharge signal, supervised training is performed on the attenuation compensation model framework to generate the attenuation compensation model.

[0050] Specifically, the attenuation compensation model is to perform field attenuation compensation for abnormal discharge signals, calling the first sample discharge signal and the second sample discharge signal, that is, the discharge signal corresponding to the discharge position and the receiving position, the first sample discharge signal and the second sample discharge signal correspond one to one, and the signal transmission distances between different corresponding sample discharge signals are different. The attenuation compensation model architecture is built based on the BP neural network, including a signal recognition layer, a field analysis layer and a compensation output layer, the field space is embedded in the field analysis layer, and the field database is connected to the attenuation compensation model to update the field space. The first sample discharge signal and the second sample discharge signal are mapped and associated as input information, and the attenuation degree is analyzed based on the corresponding transmission distance to determine the sample attenuation information. The sample attenuation information is used as compensation information and combined with the input information to generate training data, and the attenuation compensation model architecture is supervised and trained to obtain the constructed attenuation compensation model. The attenuation analysis of the input signal is performed based on the attenuation compensation model, which can effectively ensure the accuracy and objectivity of the analysis results.

[0051] Furthermore, the identification signal source is identified to determine the location where the local discharge exists, and the transmission distance is determined by combining the signal receiving probe corresponding to the abnormal discharge signal, which is used as an attenuation analysis constraint and input into the attenuation compensation model in combination with the abnormal discharge signal. Each abnormal discharge signal is individually identified in the signal identification layer and transmitted to the field analysis layer. The attenuation degree of each abnormal discharge signal under the corresponding transmission distance is determined in combination with the field space, and then transmitted to the compensation output layer. The corresponding abnormal discharge signal is compensated based on the attenuation degree, and the compensated discharge signal is obtained and output to eliminate the spatial transmission attenuation caused by the field influence.

[0052] Step S500: performing penetration loss compensation on the compensation discharge signal, inputting the signal into a defect recognition model, and outputting a defect recognition result, wherein the defect recognition model is embedded with the defect database;

[0053] Furthermore, the penetration loss compensation is performed on the compensation discharge signal, and step S500 of the present application further includes:

[0054] Step S510: performing spatial transmission obstacle detection on the target area to obtain regional obstacle distribution;

[0055] Step S520: constructing a loss reference table based on the installation positions of the intermediate joints of the cables in the target area and the obstacle distribution in the area;

[0056] Step S530: Based on the regional obstacle distribution, spatially transmitting and locating the abnormal discharge signal to determine the local obstacle distribution;

[0057] Step S540: based on the local obstacle distribution and the abnormal discharge signal, traverse the loss reference table to obtain the penetration loss;

[0058] Step S550: Based on the penetration loss, perform superposition compensation on the compensation discharge signal.

[0059] Furthermore, the output of the defect identification result, in the present application, further includes step S560, including:

[0060] Step S561: constructing the defect recognition model, wherein the defect recognition model includes a first defect detection sub-model and a second defect detection sub-model, wherein the first defect detection sub-model is used for a straight-through intermediate joint, and the second defect detection sub-model is used for a bent-through intermediate joint;

[0061] Step S562: grouping the compensated discharge signals after penetration loss compensation based on the identification signal source, inputting the signals into the defect recognition model, and obtaining the defect recognition results.

[0062] Specifically, since the high-voltage cable is laid outdoors and buried, there is penetration attenuation for soil, gravel, etc. during the transmission process, and these are used as spatial transmission obstacles for obstacle attenuation compensation. Specifically, the spatial transmission obstacles in the target area are detected, such as gravel distribution, soil density differentiation, etc., and the detection results are spatially arranged in the region to generate the regional obstacle distribution. Further, based on the installation position of the intermediate joint of the cable in the target area and the regional obstacle distribution, the penetration loss under different transmission directions and different transmission distances with each installation position as the initial point is determined, and auxiliary equipment can be used in combination with expert experience to measure and determine, and they are integrated to generate the loss reference table.

[0063] Furthermore, the abnormal discharge signal is spatially transmitted and located in the regional obstacle distribution, and the area corresponding to the spatial transmission position and distance is used as the local obstacle distribution, and the local obstacle distribution corresponds to the abnormal discharge signal one by one. The loss reference table is traversed to match the local obstacle distribution, and the penetration loss corresponding to the matching result is used as the penetration loss of the abnormal discharge signal. Then, based on the compensated discharge signal, signal compensation is performed again based on the corresponding penetration loss to further reduce the signal attenuation and improve the signal restoration. The defect recognition model is constructed, and the compensated discharge signal after the penetration loss compensation is input into the defect recognition model for defect analysis to determine the insulation defect of the intermediate joint.

[0064] Specifically, using the straight-through intermediate joint as an index, a big data search is performed to call historical detection records, sample partial discharge signals and sample defect recognition results are extracted, and they are mapped and associated to form training data, and a neural network training is performed to generate the first defect detection model; similarly, using the bent-through intermediate joint as an index, sample data is called and trained to build the second defect detection sub-model. The first defect detection sub-model and the second defect detection sub-model are constructed in the same way, but with different specific construction data, and are used to conduct targeted analysis on different intermediate joint types to improve the accuracy of the analysis. Furthermore, the defect database is grouped based on the type of intermediate joint, and the grouping results are connected to the first defect detection sub-model and the second defect detection sub-model for signal analysis reference.

[0065] Furthermore, based on the identification signal source, the intermediate joint type of the compensated discharge signal after penetration loss compensation is determined, and grouped based on this, and then input into the first defect detection sub-model and the second defect detection sub-model in the defect recognition model, and the output results of each sub-model are integrated and regularized, and output as the defect recognition result for the model.

[0066] Step S600: Based on the installation position of the intermediate joint of the cable in the target area, the cable transmission loss analysis of the electrical signal is performed to determine the conductivity detection result;

[0067] Furthermore, if Figure 3 As shown, based on the installation position of the intermediate joint of the cable in the target area, the cable transmission loss analysis of the electrical signal is performed to determine the conductivity detection result. Step S600 of the present application also includes:

[0068] Step S610: determining a plurality of groups of positioning points based on the installation position of the intermediate joint of the cable in the target area, wherein the plurality of groups of positioning points are distributed at predetermined distances between two ends of the intermediate joint;

[0069] Step S620: Based on the multiple groups of positioning points, perform cable transmission signal detection to obtain multiple groups of electrical signal detection results;

[0070] Step S630: traversing the plurality of groups of electrical signal detection results to perform differential analysis, and determining whether the signal transmission deviation meets a transmission loss threshold, wherein the transmission loss threshold is determined based on the predetermined distance;

[0071] Step S640: If the signal transmission deviation meets the transmission loss threshold, the conduction loss is determined and the corresponding intermediate connector is marked and added to the conductivity detection result.

[0072] Specifically, by performing differential analysis on the transmission signals at both ends of the intermediate joint, the conductivity analysis of the intermediate joint is performed based on the signal deviation after eliminating the cable transmission loss. Based on the installation position of the intermediate joint of the cable in the target area, the predetermined distance is a custom analysis distance, and the points at the predetermined distances at both ends of each intermediate joint are used as a group of positioning points, and the multiple groups of positioning points are obtained, and the order of each group of positioning points is determined based on the transmission direction of the signal in the cable.

[0073] Based on the multiple groups of positioning points, the cable transmission signal detection is performed, and the information of the multiple groups of positioning points can be retrieved and retrieved based on the cable management system to obtain the multiple groups of electrical signal detection results, which correspond to the multiple groups of positioning points one by one. Determine the cable transmission loss at a predetermined distance, traverse the multiple groups of electrical signal detection results to perform deviation analysis, determine multiple signal deviations, and compensate the multiple signal deviations based on the cable transmission loss. The compensated multiple signal deviations are based on the conduction loss of the intermediate joint.

[0074] Furthermore, the transmission loss threshold is set, that is, the maximum transmission loss under normal conduction conditions determined based on the intermediate joint operation and maintenance standards, and it is determined whether the conduction loss meets the transmission loss threshold. If so, it indicates that the conduction loss of the corresponding intermediate joint exceeds the limit, and the conduction loss excess amount is calculated, that is, the difference between the excess conduction loss and the transmission loss threshold, and the corresponding intermediate joint is marked and added to the conductivity detection result.

[0075] Step S700: Based on the conductivity detection result and the defect identification result, a plurality of defect sequences are determined as defect detection results.

[0076] Furthermore, based on the continuity test result and the defect identification result, a plurality of defect sequences are determined as defect detection results. Step S700 of the present application further includes:

[0077] Step S710: Based on the defect location, homologously integrating the conductivity test result and the defect identification result to generate a homologous test sequence group;

[0078] Step S720: Based on the defect type, the continuity test result and the defect identification result are homologously integrated to generate a two-item homologous test sequence group;

[0079] Step S730: mapping and associating the one homologous detection sequence group with the two homologous detection sequence groups to obtain the defect detection result.

[0080] Specifically, the conductivity test result and the defect identification result are test results based on different test standards of the intermediate joint of the high-voltage cable, and the conductivity test result and the defect identification result are integrated and regularized to generate the defect detection result. Specifically, the defect position is used as the regularization standard, at least one of the conductivity test result and the defect identification result corresponding to the defect position is determined, and a defect sequence is generated. Multiple defect sequences are generated for different defect positions and integrated as the homologous detection sequence group.

[0081] Similarly, the defect type is used as a regularization standard to determine the conductivity test results corresponding to the same defect type and at least one of the defect identification results, including the test results of different defect locations, and serialized and integrated as a set of defect sequences. Multiple defect sequences are generated for different defect types and integrated as the two homologous detection sequence groups. The one homologous detection sequence group and the two homologous detection sequence groups are further hierarchically mapped and associated as the defect detection result. By regularly associating the results, it provides convenience for the subsequent operation and maintenance management of the cable intermediate joint.

[0082] Embodiment 2

[0083] Based on the same inventive concept as the method for detecting defects in a high-voltage cable intermediate joint in the aforementioned embodiment, Figure 4 As shown, the present application provides a system for detecting defects in intermediate joints of high-voltage cables, the system comprising:

[0084] A database building module 11, wherein the database building module 11 is used to build a defect database based on the intermediate joint type and the cable installation status;

[0085] A signal receiving module 12, the signal receiving module 12 is used to locate the installation position of the middle joint of the cable in the target area, and receive the abnormal discharge signal of the partial discharge, the abnormal discharge signal carries a signal source identification;

[0086] A field space acquisition module 13, wherein the field space acquisition module 13 is used to perform spatial field restoration on the target area to be detected and acquire the field space, wherein the field space is a fitting field based on the environmental field, the magnetic field and the electric field;

[0087] An attenuation compensation module 14, the attenuation compensation module 14 is used to input the abnormal discharge signal into an attenuation compensation model and output a compensated discharge signal, the attenuation compensation model is embedded with the field space;

[0088] A defect recognition module 15, the defect recognition module 15 is used to perform penetration loss compensation on the compensation discharge signal, input it into a defect recognition model, and output a defect recognition result, wherein the defect recognition model is embedded with the defect database;

[0089] A continuity detection module 16, the continuity detection module 16 is used to perform cable transmission loss analysis of electrical signals based on the installation position of the middle joint of the cable in the target area, and determine the continuity detection result;

[0090] The result acquisition module 17 is used to determine a plurality of defect sequences as defect detection results based on the conductivity detection result and the defect identification result.

[0091] Furthermore, the field space acquisition module further includes:

[0092] A field monitoring module, the field monitoring module is used to perform field monitoring on the target area and store the data in a field database, the field database is capable of timeliness and updating;

[0093] An information extraction module, the information extraction module is used to extract field information of a predetermined time sequence based on the field database, the field information including environmental field information, magnetic field information and electric field information;

[0094] A field restoration module, the field restoration module is used to perform field restoration based on the environmental field information, the magnetic field information and the electric field information to obtain a multivariate field;

[0095] A space fitting module is used to perform space fitting on the multivariate field to generate the field space.

[0096] Furthermore, the attenuation compensation module further includes:

[0097] A sample calling module, the sample calling module is used to call a first sample discharge signal and a second sample discharge signal, the first sample discharge signal and the second sample discharge signal are mapped correspondingly and have different signal transmission distances;

[0098] An architecture building module, the architecture building module is used to build an attenuation compensation model architecture and embed it into the field space, the field database is connected to the attenuation compensation model, and is used to update the field space;

[0099] A model training module, wherein the model training module is used to perform supervised training on the attenuation compensation model architecture based on the first sample discharge signal and the second sample discharge signal to generate the attenuation compensation model.

[0100] Furthermore, the attenuation compensation module further includes:

[0101] A transmission obstacle detection module, the transmission obstacle detection module is used to perform spatial transmission obstacle detection on the target area and obtain regional obstacle distribution;

[0102] A loss reference table building module, the loss reference table building module is used to build a loss reference table based on the installation position of the intermediate joints of the cables in the target area and the distribution of obstacles in the area;

[0103] A spatial transmission positioning module, the spatial transmission positioning module is used to perform spatial transmission positioning on the abnormal discharge signal based on the regional obstacle distribution, and determine the local obstacle distribution;

[0104] A penetration loss acquisition module, the penetration loss acquisition module is used to traverse the loss reference table to acquire the penetration loss based on the local obstacle distribution and the abnormal discharge signal;

[0105] A signal superposition compensation module is used to perform superposition compensation on the compensation discharge signal based on the penetration loss.

[0106] Furthermore, the defect identification module further includes:

[0107] A defect recognition model building module, the defect recognition model building module is used to build the defect recognition model, the defect recognition model includes a first defect detection sub-model and a second defect detection sub-model, the first defect detection sub-model is used for a straight-through intermediate joint, and the second defect detection sub-model is used for a bent-through intermediate joint;

[0108] A defect recognition result acquisition module is used to group the compensated discharge signals after penetration loss compensation based on the identification signal source, input the defect recognition model, and obtain the defect recognition result.

[0109] Furthermore, the conductivity detection module further includes:

[0110] A positioning point determination module, the positioning point determination module is used to determine multiple groups of positioning points based on the installation position of the intermediate joint of the cable in the target area, and the multiple groups of positioning points are distributed at predetermined distances at both ends of the intermediate joint;

[0111] A cable transmission signal detection module, the cable transmission signal detection module is used to perform cable transmission signal detection based on the multiple groups of positioning points to obtain multiple groups of electrical signal detection results;

[0112] A threshold judgment module, the threshold judgment module is used to traverse the multiple groups of electrical signal detection results to perform differential analysis, and judge whether the signal transmission deviation meets the transmission loss threshold, and the transmission loss threshold is determined based on the predetermined distance;

[0113] A module for obtaining a continuity test result is used to determine the continuity loss and mark the corresponding intermediate joint if the signal transmission deviation meets the transmission loss threshold, and add the mark to the continuity test result.

[0114] Furthermore, the result acquisition module further includes:

[0115] a homologous detection sequence group generating module, the homologous detection sequence group generating module is used to perform homologous integration of the conductivity detection result and the defect identification result based on the defect position to generate a homologous detection sequence group;

[0116] A binary homologous detection sequence group generation module, the binary homologous detection sequence group generation module is used to perform homologous integration of the conductivity detection result and the defect identification result based on the defect type to generate a binary homologous detection sequence group;

[0117] A defect detection result acquisition module is used to map and associate the one homologous detection sequence group with the two homologous detection sequence groups as the defect detection result.

[0118] Through the above-mentioned detailed description of a method for detecting defects in intermediate joints of high-voltage cables in this specification, those skilled in the art can clearly understand a method for detecting defects in intermediate joints of high-voltage cables in this embodiment. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0119] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be 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 the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for detecting defects in a high-voltage cable intermediate joint, characterized in that: The method comprises: Build a defect database based on the intermediate joint type and cable installation status; Locate the installation position of the middle joint of the cable in the target area, and receive the abnormal discharge signal of the partial discharge, wherein the abnormal discharge signal carries a signal source identifier; Perform spatial field restoration on the target area to be detected to obtain a field space, where the field space is a fitting field based on the environmental field, the magnetic field and the electric field; Inputting the abnormal discharge signal into an attenuation compensation model and outputting a compensation discharge signal, wherein the attenuation compensation model is embedded with the field space; Performing penetration loss compensation on the compensation discharge signal, inputting the signal into a defect recognition model, and outputting a defect recognition result, wherein the defect recognition model is embedded with the defect database; Based on the installation position of the intermediate joint of the cable in the target area, performing cable transmission loss analysis of the electrical signal to determine the conductivity test result; Based on the conductivity detection result and the defect identification result, determining a plurality of groups of defect sequences as defect detection results; Wherein, based on the conductivity detection result and the defect identification result, a plurality of defect sequences are determined as defect detection results, and the method includes: Based on the defect location, homologously integrating the conductivity test result and the defect identification result to generate a homologous test sequence group; Based on the defect type, homologously integrating the conductivity test result and the defect identification result to generate a two-item homologous test sequence group; The one homologous detection sequence group and the two homologous detection sequence groups are mapped and associated to serve as the defect detection result.

2. The method according to claim 1, characterized in that The method of performing spatial field restoration on the target area to be detected to obtain the field space includes: Performing field monitoring on the target area and storing the data in a field database, wherein the field database has timeliness and updateability; Based on the field database, extracting field information of a predetermined time sequence, the field information including environmental field information, magnetic field information and electric field information; Performing field restoration based on the environmental field information, the magnetic field information and the electric field information to obtain a multivariate field; Performing spatial fitting on the multivariate field to generate the field space.

3. The method according to claim 2, characterized in that Build an attenuation compensation model, including: Calling a first sample discharge signal and a second sample discharge signal, wherein the first sample discharge signal and the second sample discharge signal are mapped correspondingly and have different signal transmission distances; Building an attenuation compensation model framework and embedding it into the field space, wherein the field database is connected to the attenuation compensation model for updating the field space; Based on the first sample discharge signal and the second sample discharge signal, supervised training is performed on the attenuation compensation model architecture to generate the attenuation compensation model.

4. The method according to claim 3, characterized in that The method of performing penetration loss compensation on the compensation discharge signal comprises: Performing spatial transmission obstacle detection on the target area to obtain regional obstacle distribution; Building a loss reference table based on the installation positions of the intermediate joints of the cables in the target area and the distribution of obstacles in the area; Based on the regional obstacle distribution, spatially transmitting and locating the abnormal discharge signal to determine the local obstacle distribution; Based on the local obstacle distribution and the abnormal discharge signal, traverse the loss reference table to obtain the penetration loss; Based on the penetration loss, the compensation discharge signal is superimposed and compensated.

5. The method according to claim 1, characterized in that The method for outputting defect identification results includes: Building the defect recognition model, the defect recognition model includes a first defect detection sub-model and a second defect detection sub-model, the first defect detection sub-model is used for a straight-through intermediate joint, and the second defect detection sub-model is used for a bent-through intermediate joint; The compensated discharge signals after penetration loss compensation are grouped based on the identification signal source, input into the defect recognition model, and obtain the defect recognition result.

6. The method according to claim 1, characterized in that The method of performing cable transmission loss analysis of electrical signals based on the installation position of the intermediate joint of the cable in the target area to determine the conductivity detection result includes: Based on the installation position of the intermediate joint of the cable in the target area, a plurality of groups of positioning points are determined, wherein the plurality of groups of positioning points are distributed at predetermined distances at both ends of the intermediate joint; Based on the multiple groups of positioning points, cable transmission signal detection is performed to obtain multiple groups of electrical signal detection results; Traversing the plurality of groups of electrical signal detection results to perform differential analysis, and determining whether the signal transmission deviation satisfies a transmission loss threshold, wherein the transmission loss threshold is determined based on the predetermined distance; If the signal transmission deviation meets the transmission loss threshold, the conduction loss is determined and the corresponding intermediate joint is marked and added to the conductivity detection result.

7. A system for detecting defects in high-voltage cable intermediate joints, characterized in that: For executing the method according to any one of claims 1 to 6, the system comprises: A database building module, the database building module is used to build a defect database based on the intermediate joint type and the cable installation status; A signal receiving module, the signal receiving module is used to locate the installation position of the middle joint of the cable in the target area, and receive the abnormal discharge signal of the partial discharge, the abnormal discharge signal carries a signal source identifier; A field space acquisition module, which is used to perform spatial field restoration on the target area to be detected and acquire the field space, wherein the field space is a fitting field based on the environmental field, the magnetic field and the electric field; An attenuation compensation module, the attenuation compensation module is used to input the abnormal discharge signal into an attenuation compensation model and output a compensated discharge signal, the attenuation compensation model is embedded with the field space; A defect recognition module, the defect recognition module is used to perform penetration loss compensation on the compensation discharge signal, input it into a defect recognition model, and output a defect recognition result, wherein the defect recognition model is embedded with the defect database; A continuity detection module, the continuity detection module is used to perform cable transmission loss analysis of electrical signals based on the installation position of the middle joint of the cable in the target area, and determine the continuity detection result; A result acquisition module is used to determine a plurality of defect sequences as defect detection results based on the conductivity detection result and the defect identification result.

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