Defect detection system and method in operation process of cable joint

Abstract

The embodiment of the invention discloses a defect detection system and method in the operation process of a cable connector, and the method comprises the steps: receiving partial discharge information every preset voltage period, and enabling the partial discharge information to comprise the signal amplitude, the discharge frequency and the phase angle of a partial discharge signal at each time point; acquiring a plurality of preset defects and corresponding defect feature information, performing similarity comparison processing on the signal amplitude, the discharge frequency and the phase angle of the partial discharge signal at each time point and each piece of defect feature information, and determining a plurality of to-be-determined defects according to a similarity comparison processing result, and obtaining preset influence parameter information of the plurality of to-be-determined defects, and determining a final defect based on the plurality of to-be-determined defects and the corresponding preset influence parameter information. According to the scheme, defect identification is carried out through the partial discharge information and the pre-stored defect features, and a final defect conclusion is obtained by comprehensively analyzing a plurality of identification results, so that the reasonability and the accuracy of defect detection of the cable joint can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of cable defect detection, and in particular, to a system and method for detecting defects during the operation of a cable joint. Background Art

[0002] The main function of the cable joint is to connect the various sections of the cable into a whole, ensuring the continuity of the line and the stability of the electrical connection. Cable joints play a vital role in the cable system. They not only connect the various parts of the cable, but also play a role in waterproofing, dustproofing and vibration prevention, thereby protecting the cable from the influence of the external environment. The proportion of cable joint breakdown failures accounts for a higher proportion of the total number of cable operation failures, which is much higher than the cable body, and the occurrence of partial discharge indicates that the insulation of the high-voltage cable may be defective. Defects in cable joints may cause damage or failure of the insulation layer, short circuit, overload and other problems. Therefore, defect detection of cable joints is crucial.

[0003] In the related technologies, most of them require staff to regularly go to the site to inspect and repair the cable joints for defects or to determine whether there are defects by inspecting the operating parameters of the cable joint position. There is a lack of reasonable detection methods for cable joint defects, and defects in cable joints cannot be discovered in time, which affects the operation of the power system. Summary of the invention

[0004] The embodiments of the present invention provide a system and method for detecting defects in a cable joint during operation, which solves the problem that the related art lacks a reasonable detection method for cable joint defects, the defects of the cable joint cannot be discovered in time, and the operation of the power system is affected, and can improve the rationality and accuracy of cable joint defect detection.

[0005] In a first aspect, an embodiment of the present invention provides a method for detecting defects in a cable connector during operation, comprising:

[0006] receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number, and a power frequency voltage phase angle of the partial discharge signal at each time point;

[0007] Acquire multiple preset defects and corresponding defect feature information, perform similarity comparison processing with each of the defect feature information based on the signal amplitude, discharge number and power frequency voltage phase angle of the partial discharge signal at each time point, and determine multiple defects to be determined from the multiple preset defects according to the similarity comparison processing result;

[0008] The preset influencing parameter information of the plurality of defects to be determined is obtained, and a final defect is determined based on the plurality of defects to be determined and the corresponding preset influencing parameter information.

[0009] Optionally, the defect characteristic information includes amplitude phase distribution characteristic data and discharge number phase distribution characteristic data, and the signal amplitude, discharge number and power frequency voltage phase angle of the partial discharge signal based on each time point are compared with each of the defect characteristic information for similarity, including:

[0010] Determine the amplitude-phase distribution similarity according to the signal amplitude, the power frequency voltage phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information, and determine the discharge number phase distribution similarity according to the discharge number, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information;

[0011] The amplitude phase distribution similarity and the discharge number phase distribution similarity are respectively multiplied by corresponding preset weights and superimposed to obtain a comprehensive similarity.

[0012] Optionally, the amplitude-phase distribution characteristic data includes a characteristic amplitude range and a corresponding phase angle distribution range, and the determining of the amplitude-phase distribution similarity according to the signal amplitude, the power frequency voltage phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information includes:

[0013] Screening out each signal amplitude corresponding to the power frequency voltage phase angle within the phase angle distribution range, and determining it as the amplitude to be compared;

[0014] Each of the amplitudes to be compared is compared with the characteristic amplitude range, the number of the amplitudes to be compared within the characteristic amplitude range is determined according to the comparison result, and the ratio of the number to the total number of the amplitudes to be compared is determined as the amplitude phase distribution similarity.

[0015] Optionally, the discharge number distribution characteristic data includes a characteristic discharge number range and a corresponding phase angle distribution range, and determining the discharge number phase distribution similarity according to the discharge number, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect feature information includes:

[0016] Screening out each discharge number corresponding to the power frequency voltage phase angle within the phase angle distribution range, and determining it as the discharge number to be compared;

[0017] Each of the discharge times to be compared is compared with the characteristic discharge times range, and the number of discharge times to be compared within the characteristic discharge times range is determined according to the comparison result, and the ratio of the number to the total number of discharge times to be compared is determined as the discharge times phase distribution similarity.

[0018] Optionally, determining a plurality of defects to be determined from the plurality of preset defects according to the similarity comparison processing result includes:

[0019] The comprehensive similarities corresponding to the preset defects are arranged in descending order to obtain a similarity sequence, and the comprehensive similarities of a preset proportion of the similarity sequence are selected, and the preset defects corresponding to the selected comprehensive similarities are determined as defects to be determined.

[0020] Optionally, the preset influencing parameter information includes influencing cable parameters and corresponding defect conditions, and determining the final defect based on the plurality of defects to be determined and the corresponding preset influencing parameter information includes:

[0021] The monitoring values ​​of the influencing cable parameters corresponding to each of the defects to be determined within a preset time are obtained, and the final defect is determined based on the monitoring values ​​of each of the influencing cable parameters within the preset time and the corresponding defect conditions.

[0022] Optionally, the defect condition includes a defect monitoring value range and a defect change trend, and determining the final defect based on the monitoring values ​​of each of the influencing cable parameters within a preset time and the corresponding defect condition includes:

[0023] According to the monitoring values ​​of each of the cable-affecting parameters within a preset time, the corresponding average monitoring value and the monitoring value change trend are calculated respectively. When the average monitoring value is within the corresponding defect monitoring value range and the monitoring value change trend is the corresponding defect change trend, the corresponding defect to be determined is determined as the final defect.

[0024] In a second aspect, an embodiment of the present invention further provides a defect detection system during operation of a cable connector, comprising:

[0025] A receiving module, used for receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number and a power frequency voltage phase angle of the partial discharge signal at each time point;

[0026] An acquisition module, used to acquire multiple preset defects and corresponding defect feature information;

[0027] A comparison processing module, used for performing similarity comparison processing with each defect feature information based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point;

[0028] A to-be-determined defect determination module, used to determine a plurality of to-be-determined defects from a plurality of the preset defects according to the similarity comparison processing result;

[0029] The acquisition module is further used to acquire preset influencing parameter information of a plurality of defects to be determined;

[0030] The final defect determination module is used to determine the final defect based on the multiple defects to be determined and the corresponding preset influencing parameter information.

[0031] In a third aspect, an embodiment of the present invention further provides a defect detection device during operation of a cable connector, the device comprising:

[0032] one or more processors;

[0033] a storage device for storing one or more programs,

[0034] When the one or more programs are executed by the one or more processors, the one or more processors implement a method for detecting defects in the operation process of a cable joint as described in an embodiment of the present invention.

[0035] In a fourth aspect, an embodiment of the present invention further provides a storage medium storing computer executable instructions, wherein the computer executable instructions, when executed by a computer processor, are used to execute a defect detection method during operation of a cable connector as described in an embodiment of the present invention.

[0036] In the embodiment of the present invention, the partial discharge information sent by the partial discharge monitoring device is received every preset voltage cycle, and the partial discharge information includes the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point, and multiple preset defects and corresponding defect feature information are obtained. Based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point and each defect feature information, similarity comparison processing is performed, and multiple defects to be determined are determined from multiple preset defects according to the similarity comparison processing results, and preset influence parameter information of multiple defects to be determined is obtained. The final defect is determined based on multiple defects to be determined and the corresponding preset influence parameter information. This scheme identifies defects through partial discharge information and pre-stored defect features, and then comprehensively analyzes multiple identification results to obtain the final defect conclusion, which solves the problem that there is a lack of reasonable detection methods for cable joint defects in related technologies, and the defects of cable joints cannot be discovered in time, which affects the operation of the power system, and can improve the rationality and accuracy of cable joint defect detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A flow chart of a method for detecting defects in a cable joint during operation provided by an embodiment of the present invention;

[0038] Figure 2 A flow chart of another method for detecting defects in a cable joint during operation provided by an embodiment of the present invention;

[0039] Figure 3 A flow chart of another method for detecting defects in a cable joint during operation provided by an embodiment of the present invention;

[0040] Figure 4 A flow chart of another method for detecting defects in a cable joint during operation provided by an embodiment of the present invention;

[0041] Figure 5 A module structure block diagram of a defect detection system during operation of a cable joint provided by an embodiment of the present invention;

[0042] Figure 6 A schematic structural diagram of a defect detection device during operation of a cable connector provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention, rather than to limit the embodiments of the present invention. It is also necessary to explain that, for ease of description, only parts related to the embodiments of the present invention are shown in the accompanying drawings, rather than all structures.

[0044] The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and or or" in the specification and claims represents at least one of the connected objects, and the character "or" generally indicates that the objects associated before and after are in an "or" relationship.

[0045] The embodiment of the present application provides a method for detecting defects in the operation of a cable joint, which can be applied to the detection scenario of cable joint defects. The embodiment of the present application provides a method for detecting defects in the operation of a cable joint, in which the execution subject of each step can be a computer device, which refers to any electronic device with data calculation, processing and storage capabilities, such as mobile phones, PCs (Personal Computers), tablet computers and other terminal devices, and can also be servers and other devices, which are not limited in the embodiment of the present application.

[0046] Figure 1 A flow chart of a method for detecting defects in a cable joint during operation provided by an embodiment of the present invention is shown in FIG. Figure 1 As shown, specifically including:

[0047] Step S101: receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge frequency, and a power frequency voltage phase angle of the partial discharge signal at each time point.

[0048] Among them, the preset voltage cycle can be the time interval of the positive and negative alternating cycles of the voltage of the current cable joint measured in advance, which is relative to the power frequency voltage phase angle. The partial discharge monitoring device can be a related device used to monitor partial discharge events at the cable joint, such as a partial discharge monitor. The partial discharge information can be the relevant information of the partial discharge event monitored at the cable joint. The partial discharge signal can be a physical signal generated by the discharge phenomenon occurring in the local range of the insulating part of the cable joint. The signal amplitude is used to characterize the magnitude of the electric field strength during the partial discharge process. The number of discharges is used to characterize the frequency of occurrence of discharge events. The power frequency voltage phase angle refers to the phase difference of the power frequency voltage relative to the reference point. The power frequency voltage phase angle can be calculated by the signal processing of the partial discharge signal by the partial discharge monitoring device. An exemplary example can be that the preset voltage cycle is 0.02s, and the signal amplitude, discharge number and power frequency voltage phase angle of the partial discharge signal sent by the partial discharge monitoring device at each time point are received every 0.02s, and the power frequency voltage phase angle is from 0° to 360° for a complete voltage cycle.

[0049] Step S102, obtaining a plurality of preset defects and corresponding defect characteristic information, performing a similarity comparison process with each of the defect characteristic information based on the signal amplitude, the number of discharges and the phase angle of the power frequency voltage of the partial discharge signal at each time point, and determining a plurality of defects to be determined from the plurality of preset defects according to the similarity comparison process result.

[0050] Among them, the preset defect can be a pre-set defect that may occur in the cable joint, such as an air gap defect, a spike defect, a fracture defect, etc. The defect characteristic information can be the distribution characteristic phenomenon of the local discharge phenomenon of the preset defect in the phase angle. The defect to be determined is used to characterize the preset defect waiting to be determined whether it is the final defect of the cable joint. In one embodiment, after obtaining multiple preset defects and corresponding defect characteristic information, a phase-resolved partial discharge image is generated based on the signal amplitude, discharge number and power frequency voltage phase angle of the local discharge signal at each time point, and the feature information of the phase-resolved partial discharge image is identified according to the trained feature recognition model, and the similarity between the feature information and each defect feature information is calculated respectively. Optionally, the defect characteristic information includes amplitude phase distribution characteristic data and discharge number phase distribution characteristic data. A similarity comparison processing method may be to determine the amplitude phase distribution similarity according to the signal amplitude of the local discharge signal at each time point, the power frequency voltage phase angle and the amplitude phase distribution characteristic data in the defect characteristic information, determine the discharge number phase distribution similarity according to the discharge number of the local discharge signal at each time point, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information, and multiply the amplitude phase distribution similarity and the discharge number phase distribution similarity with the corresponding preset weights and superimpose them to obtain the comprehensive similarity. By performing similarity comparison processing on the distribution characteristics of the amplitude of the local discharge phenomenon of the cable joint and the number of discharges at the phase angle, the rationality and accuracy of the subsequent determination of the defects to be determined can be improved.

[0051] In one embodiment, after the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point are compared with each defect feature information, the comprehensive similarity corresponding to each preset defect is compared with the preset similarity, and each preset defect greater than the preset similarity is determined as a defect to be determined. Optionally, a method for determining the defect to be determined may be to arrange the comprehensive similarities corresponding to each preset defect in order from large to small to obtain a similarity sequence, select each comprehensive similarity of a preset proportion in the similarity sequence, and determine the preset defects corresponding to each selected comprehensive similarity as the defect to be determined. By setting a ratio to determine multiple defects to be determined from each defect whose similarity is arranged from large to small, the rationality of the defect to be determined can be ensured.

[0052] Step S103: obtaining preset influencing parameter information of the plurality of defects to be determined, and determining a final defect based on the plurality of defects to be determined and the corresponding preset influencing parameter information.

[0053] Among them, the preset influencing parameter information may be the relevant information of the cable joint parameters affected by the defects to be determined. The final defect is used to characterize the defects finally determined to exist in the cable joint. In one embodiment, after obtaining the preset influencing parameter information of multiple defects to be determined, the current monitoring values ​​of the preset influencing cable parameters corresponding to each defect to be determined are obtained, and the monitoring values ​​corresponding to each defect to be determined are respectively compared with the corresponding preset values, and the final defect is determined from the multiple defects to be determined according to the comparison results. Optionally, the preset influencing parameter information includes the influencing cable parameters and the corresponding defect conditions. A method for determining the final defect may be to obtain the monitoring values ​​of the influencing cable parameters corresponding to each defect to be determined within a preset time, and determine the final defect based on the monitoring values ​​of each influencing cable parameter within a preset time and the corresponding defect conditions. Determining the final defect by the monitoring information of the influencing cable parameters of the defects to be determined and the corresponding defect conditions can improve the rationality and accuracy of the finally determined cable joint defects.

[0054] As can be seen from the above, the partial discharge information sent by the partial discharge monitoring device is received every preset voltage cycle, and the partial discharge information includes the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point, and multiple preset defects and corresponding defect feature information are obtained. Based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point and each defect feature information, similarity comparison processing is performed, and multiple defects to be determined are determined from multiple preset defects according to the similarity comparison processing results, and preset influencing parameter information of multiple defects to be determined is obtained. The final defect is determined based on multiple defects to be determined and the corresponding preset influencing parameter information. This scheme identifies defects through partial discharge information and pre-stored defect features, and then comprehensively analyzes multiple identification results to obtain the final defect conclusion, which solves the problem that there is a lack of reasonable detection methods for cable joint defects in related technologies, and the defects of cable joints cannot be discovered in time, which affects the operation of the power system, and can improve the rationality and accuracy of cable joint defect detection.

[0055] Figure 2 A flowchart of another method for detecting defects in a cable joint during operation provided by an embodiment of the present invention provides a specific method for optional similarity comparison processing, such as Figure 2 As shown, specifically including:

[0056] Step S201: receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number, and a power frequency voltage phase angle of the partial discharge signal at each time point.

[0057] Step S202, obtain multiple preset defects and corresponding defect characteristic information, determine the amplitude-phase distribution similarity according to the signal amplitude, the power frequency voltage phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information, and determine the discharge number phase distribution similarity according to the discharge number, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information.

[0058] Among them, the defect characteristic information includes amplitude-phase distribution characteristic data and discharge number phase distribution characteristic data, and the amplitude-phase distribution characteristic data can be the distribution characteristic data of the amplitude of the local discharge phenomenon of the preset defect on the power frequency voltage phase angle. The amplitude-phase distribution similarity is used to characterize the similarity between the distribution characteristics of the amplitude of the local discharge phenomenon of the cable joint on the phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information. The discharge number distribution characteristic data can be the distribution characteristic data of the number of discharges of the local discharge phenomenon of the preset defect on the power frequency voltage phase angle. Discharge number phase distribution similarity is the similarity between the distribution characteristics of the number of discharges of the local discharge phenomenon of the cable joint on the phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information. Optionally, the amplitude-phase distribution characteristic data includes a characteristic amplitude range and a corresponding phase angle distribution range. A method for determining the similarity of the amplitude-phase distribution may be to screen out each signal amplitude of the corresponding power frequency voltage phase angle within the phase angle distribution range, and determine it as the amplitude to be compared, and compare each amplitude to be compared with the characteristic amplitude range, and determine the number of amplitudes to be compared within the characteristic amplitude range according to the comparison result, and determine the ratio of this number to the total number of amplitudes to be compared as the amplitude-phase distribution similarity. Optionally, the discharge number distribution characteristic data includes a characteristic discharge number range and a corresponding phase angle distribution range. A method for determining the similarity of the discharge number-phase distribution may be to screen out each discharge number of the corresponding power frequency voltage phase angle within the phase angle distribution range, and determine it as the discharge number to be compared, and compare each discharge number to be compared with the characteristic discharge number range, and determine the number of discharge numbers to be compared within the characteristic discharge number range according to the comparison result, and determine the ratio of this number to the total number of discharge numbers to be compared as the amplitude-phase distribution similarity.An exemplary example may be that the characteristic amplitude range in the defect characteristic information of the air gap defect is 90pC to 100pC, and the corresponding phase angle distribution range is 0° to 360°. Then, each signal amplitude within the power frequency voltage phase angle of 0° to 360° in the partial discharge information is determined as the amplitude to be compared, and the total number of amplitudes to be compared is 360. Each amplitude to be compared is compared with the characteristic amplitude range, and the number of amplitudes to be compared within the characteristic amplitude range is 348. The ratio of this number to the total number of amplitudes to be compared is calculated to be 96.7%, that is, the amplitude phase distribution similarity is 96.7. %, the characteristic discharge times in the defect characteristic information of the air gap defect ranges from 5 to 10 times, and the corresponding phase angle distribution ranges from 0° to 30°, then each discharge times within the power frequency voltage phase angle of 0° to 30° in the local discharge information is determined as the discharge times to be compared, and the total number of discharge times to be compared is 30. Each discharge times to be compared is compared with the characteristic discharge times range, and the number of discharge times to be compared within the characteristic discharge times range is 28, and the ratio of this number to the total number of discharge times to be compared is calculated to be 93.3%, that is, the similarity of the discharge times phase distribution is 93.3%.

[0059] In another embodiment, the signal amplitude, power frequency voltage phase angle in the local discharge information and the amplitude and phase distribution characteristic data in the defect characteristic information of the preset defect are input into a trained similarity comparison model, and the corresponding amplitude and phase distribution similarity is output; the number of discharges, power frequency voltage phase angle in the local discharge information and the discharge number distribution characteristic data in the defect characteristic information of the preset defect are input into a trained similarity comparison model, and the corresponding discharge number and phase distribution similarity is output.

[0060] Step S203: multiply the amplitude phase distribution similarity and the discharge number phase distribution similarity with corresponding preset weights respectively and add them together to obtain comprehensive similarity, and determine multiple defects to be determined from multiple preset defects according to the similarity comparison processing results.

[0061] Among them, the comprehensive similarity can be the degree of similarity between the discharge characteristics of the partial discharge information and the defect characteristic information of the preset defect. An exemplary example can be that the amplitude phase distribution similarity corresponding to the air gap defect is determined to be 96.7%, the discharge number phase distribution similarity is 93.3%, the preset weight corresponding to the amplitude phase distribution similarity is 0.6, and the preset weight corresponding to the discharge number phase distribution similarity is 0.4, then the comprehensive similarity between the partial discharge information and the air gap defect is calculated to be 95.34% (96.7%*0.6+93.3%*0.4), and similarly, the comprehensive similarities between the partial discharge information and the spike defect, the semi-conductive dislocation defect, the insulation moisture defect, and the metal residual defect are determined to be 10%, 15%, 92%, and 91.5% respectively, and multiple defects to be determined are determined from multiple preset defects according to each comprehensive similarity.

[0062] Step S204: obtaining preset influencing parameter information of the plurality of defects to be determined, and determining a final defect based on the plurality of defects to be determined and the corresponding preset influencing parameter information.

[0063] From the above, it can be seen that the amplitude phase distribution similarity is determined according to the signal amplitude of the partial discharge signal at each time point, the power frequency voltage phase angle and the amplitude phase distribution characteristic data in the defect characteristic information, and the discharge number phase distribution similarity is determined according to the discharge number of the partial discharge signal at each time point, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information, and the amplitude phase distribution similarity and the discharge number phase distribution similarity are respectively multiplied by the corresponding preset weights and superimposed to obtain the comprehensive similarity. This scheme performs similarity comparison processing by comparing the amplitude of the partial discharge phenomenon of the cable joint and the distribution characteristics of the discharge number on the phase angle, which can improve the rationality and accuracy of the subsequent determination of the defects to be determined.

[0064] Figure 3 A flowchart of another defect detection method during operation of a cable joint provided by an embodiment of the present invention provides an optional specific method for determining a defect to be determined, such as Figure 3 As shown, specifically including:

[0065] Step S301: receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number, and a power frequency voltage phase angle of the partial discharge signal at each time point.

[0066] Step S302: obtaining a plurality of preset defects and corresponding defect characteristic information, and performing a similarity comparison process with each of the defect characteristic information based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point.

[0067] Step S303: Arrange the comprehensive similarities corresponding to the preset defects in descending order to obtain a similarity sequence, select the comprehensive similarities of a preset proportion in the similarity sequence, and determine the preset defects corresponding to the selected comprehensive similarities as the defects to be determined.

[0068] Among them, the similarity sequence is used to characterize the arrangement sequence of each comprehensive similarity from large to small. The preset ratio can be a ratio value preset according to the actual situation. An exemplary example can be that the comprehensive similarities of partial discharge information and air gap defects, spike defects, semi-conductive dislocation defects, insulation moisture defects, and metal residual defects are 95.34%, 10%, 15%, 92%, and 91.5% respectively, and the preset ratio is 60%. The comprehensive similarities corresponding to each preset defect are 95.34%, 92%, 91.5%, 15%, and 10% in order from large to small. The comprehensive similarities of 60% of the similarity sequence are 95.34%, 92%, and 91.5%, and the corresponding preset defects are air gap defects, insulation moisture defects, and metal residual defects. Then, air gap defects, insulation moisture defects, and metal residual defects are determined as defects to be determined.

[0069] Step S304: obtaining preset influencing parameter information of the plurality of defects to be determined, and determining a final defect based on the plurality of defects to be determined and the corresponding preset influencing parameter information.

[0070] As can be seen from the above, the comprehensive similarities corresponding to the preset defects are arranged in descending order to obtain a similarity sequence, and the comprehensive similarities of the preset proportion part in the similarity sequence are selected, and the preset defects corresponding to the selected comprehensive similarities are determined as the defects to be determined. This solution determines multiple defects to be determined from the defects arranged in descending order of similarity by setting a proportion, which can ensure the rationality of the defects to be determined.

[0071] Figure 4 A flowchart of another defect detection method during operation of a cable joint provided by an embodiment of the present invention provides an optional specific method for determining the final defect, such as Figure 4 As shown, specifically including:

[0072] Step S401: receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number, and a power frequency voltage phase angle of the partial discharge signal at each time point.

[0073] Step S402: obtaining a plurality of preset defects and corresponding defect characteristic information, performing a similarity comparison process with each of the defect characteristic information based on the signal amplitude, the number of discharges and the phase angle of the power frequency voltage of the local discharge signal at each time point, and determining a plurality of defects to be determined from the plurality of preset defects according to the similarity comparison process result.

[0074] Step S403, obtain preset influencing parameter information of multiple defects to be determined, obtain the monitoring value of the influencing cable parameter corresponding to each defect to be determined within a preset time, and determine the final defect based on the monitoring value of each influencing cable parameter within the preset time and the corresponding defect condition.

[0075] Among them, the preset influencing parameter information may be information related to the preset cable joint parameters affected by the defects to be determined. The preset influencing parameter information includes the influencing cable parameters and the corresponding defect conditions. The influencing cable parameters are used to characterize the cable joint parameters affected by the defects to be determined. The defect conditions are used to characterize the conditions that need to be met for the defects to occur in the influencing cable parameters. Optionally, the defect conditions include the defect monitoring value range and the defect change trend. A way to determine the final defect may be to calculate the corresponding average monitoring value and the monitoring value change trend according to the monitoring values ​​of each influencing cable parameter within a preset time. When the average monitoring value is within the corresponding defect monitoring value range and the monitoring value change trend is the corresponding defect change trend, the corresponding defect to be determined is determined as the final defect. An exemplary example may be that the cable parameter affected by the insulation damp defect is the power loss rate, the defect monitoring value range in the defect condition is (5%, 100%), the defect change trend is an upward trend, the preset time is 1 hour, and the power loss rates obtained within 1 hour are 5%, 6%, 7%, 9%, 10%, and 11% respectively. The average power loss rate is calculated to be 8%, and the power loss rate change trend is an upward trend, that is, the average power loss rate is within the corresponding defect monitoring value range and the power loss rate change trend is the corresponding defect change trend, and the insulation damp defect is determined as the final defect. In another embodiment, the corresponding average monitoring value is calculated according to the monitoring values ​​of each cable parameter within the preset time. When the average monitoring value is within the defect value range in the corresponding defect condition, the corresponding defect to be determined is determined as the final defect.

[0076] From the above, it can be seen that the monitoring values ​​of the influencing cable parameters corresponding to each defect to be determined within a preset time are obtained, and the final defect is determined based on the monitoring values ​​of each influencing cable parameter within a preset time and the corresponding defect conditions. This solution determines the final defect through the monitoring information of the influencing cable parameters of the defect to be determined and the corresponding defect conditions, which can improve the rationality and accuracy of the final determined cable joint defect.

[0077] Figure 5 This is a module structure diagram of a defect detection system for a cable joint during operation provided by an embodiment of the present invention. The system is used to execute a defect detection method for a cable joint during operation provided by the above embodiment, and has functional modules and beneficial effects corresponding to the execution method. Figure 5 As shown, the system specifically includes:

[0078] The receiving module 101 is used to receive partial discharge information sent by the partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point;

[0079] An acquisition module 102 is used to acquire a plurality of preset defects and corresponding defect feature information;

[0080] A comparison processing module 103 is used to perform similarity comparison processing with each defect feature information based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point;

[0081] A to-be-determined defect determination module 104, configured to determine a plurality of to-be-determined defects from among a plurality of the preset defects according to the similarity comparison processing result;

[0082] The acquisition module 102 is further used to acquire preset influencing parameter information of a plurality of defects to be determined;

[0083] The final defect determination module 105 is used to determine the final defect based on the multiple defects to be determined and the corresponding preset influencing parameter information.

[0084] It can be seen from the above scheme that the partial discharge information sent by the partial discharge monitoring device is received every preset voltage cycle, and the partial discharge information includes the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point, and multiple preset defects and corresponding defect feature information are obtained. Based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point and each defect feature information, similarity comparison processing is performed, and multiple defects to be determined are determined from multiple preset defects according to the similarity comparison processing results, and preset influencing parameter information of multiple defects to be determined is obtained. The final defect is determined based on multiple defects to be determined and the corresponding preset influencing parameter information. This scheme identifies defects through partial discharge information and pre-stored defect features, and then comprehensively analyzes multiple identification results to obtain the final defect conclusion, which solves the problem that there is a lack of reasonable detection methods for cable joint defects in related technologies, and the defects of cable joints cannot be discovered in time, which affects the operation of the power system, and can improve the rationality and accuracy of cable joint defect detection.

[0085] In a possible embodiment, the comparison processing module 103 is specifically used to:

[0086] Determine the amplitude-phase distribution similarity according to the signal amplitude, the power frequency voltage phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information, and determine the discharge number phase distribution similarity according to the discharge number, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information;

[0087] The amplitude phase distribution similarity and the discharge number phase distribution similarity are respectively multiplied by corresponding preset weights and superimposed to obtain a comprehensive similarity.

[0088] In a possible embodiment, the comparison processing module 103 is further used for:

[0089] Screening out each signal amplitude corresponding to the power frequency voltage phase angle within the phase angle distribution range, and determining it as the amplitude to be compared;

[0090] Each of the amplitudes to be compared is compared with the characteristic amplitude range, the number of the amplitudes to be compared within the characteristic amplitude range is determined according to the comparison result, and the ratio of the number to the total number of the amplitudes to be compared is determined as the amplitude phase distribution similarity.

[0091] In a possible embodiment, the comparison processing module 103 is further used for:

[0092] Screening out each discharge number corresponding to the power frequency voltage phase angle within the phase angle distribution range, and determining it as the discharge number to be compared;

[0093] Each of the discharge times to be compared is compared with the characteristic discharge times range, and the number of discharge times to be compared within the characteristic discharge times range is determined according to the comparison result, and the ratio of the number to the total number of discharge times to be compared is determined as the discharge times phase distribution similarity.

[0094] In a possible embodiment, the to-be-determined defect determination module 104 is specifically configured to:

[0095] The comprehensive similarities corresponding to the preset defects are arranged in descending order to obtain a similarity sequence, and the comprehensive similarities of a preset proportion of the similarity sequence are selected, and the preset defects corresponding to the selected comprehensive similarities are determined as defects to be determined.

[0096] In a possible embodiment, the final defect determination module 105 is specifically configured to:

[0097] The monitoring values ​​of the influencing cable parameters corresponding to each of the defects to be determined within a preset time are obtained, and the final defect is determined based on the monitoring values ​​of each of the influencing cable parameters within the preset time and the corresponding defect conditions.

[0098] In a possible embodiment, the final defect determination module 105 is further configured to:

[0099] According to the monitoring values ​​of each of the cable-affecting parameters within a preset time, the corresponding average monitoring value and the monitoring value change trend are calculated respectively. When the average monitoring value is within the corresponding defect monitoring value range and the monitoring value change trend is the corresponding defect change trend, the corresponding defect to be determined is determined as the final defect.

[0100] Figure 6 A schematic diagram of a defect detection device for a cable connector during operation provided by an embodiment of the present invention is shown in FIG. Figure 6 As shown, the device includes a processor 201, a memory 202, an input device 203 and an output device 204; the number of processors 201 in the device can be one or more. Figure 6 A processor 201 is taken as an example; the processor 201, memory 202, input device 203 and output device 204 in the device can be connected by a bus or other means. Figure 6 The example of connecting via a bus is taken. The memory 202, as a computer-readable storage medium, can be used to store software programs, computer executable programs and modules, such as program instructions or modules corresponding to a defect detection method during operation of a cable connector in an embodiment of the present invention. The processor 201 executes various functional applications and data processing of the device by running the software programs, instructions and modules stored in the memory 202, that is, implements the above-mentioned defect detection method during operation of a cable connector. The input device 203 can be used to receive input digital or character information, and generate key signal input related to user settings and function control of the device. The output device 204 may include a display device such as a display screen.

[0101] An embodiment of the present invention further provides a storage medium comprising computer executable instructions, wherein the computer executable instructions are used to execute a method for detecting defects in a cable connector during operation when the computer processor executes the instructions, the method comprising:

[0102] receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number, and a power frequency voltage phase angle of the partial discharge signal at each time point;

[0103] Acquire multiple preset defects and corresponding defect feature information, perform similarity comparison processing with each of the defect feature information based on the signal amplitude, discharge number and power frequency voltage phase angle of the partial discharge signal at each time point, and determine multiple defects to be determined from the multiple preset defects according to the similarity comparison processing result;

[0104] The preset influencing parameter information of the plurality of defects to be determined is obtained, and a final defect is determined based on the plurality of defects to be determined and the corresponding preset influencing parameter information.

[0105] It is worth noting that in the embodiment of the defect detection method system during the operation of the above-mentioned cable connector, the various units and modules included are divided only according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be achieved; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the protection scope of the embodiments of the present invention.

[0106] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the embodiments of the present invention are not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the embodiments of the present invention. Therefore, although the embodiments of the present invention are described in more detail through the above embodiments, the embodiments of the present invention are not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the embodiments of the present invention, and the scope of the embodiments of the present invention is determined by the scope of the appended claims.

Claims

1. A method for detecting defects in a cable joint during operation, applied to a server, characterized in that: include: receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number, and a power frequency voltage phase angle of the partial discharge signal at each time point; Acquire multiple preset defects and corresponding defect feature information, perform similarity comparison processing with each of the defect feature information based on the signal amplitude, discharge number and power frequency voltage phase angle of the partial discharge signal at each time point, and determine multiple defects to be determined from the multiple preset defects according to the similarity comparison processing result; The preset influencing parameter information of the plurality of defects to be determined is obtained, and a final defect is determined based on the plurality of defects to be determined and the corresponding preset influencing parameter information.

2. The defect detection method during operation of a cable joint according to claim 1 is characterized in that: The defect characteristic information includes amplitude phase distribution characteristic data and discharge number phase distribution characteristic data, and the signal amplitude, discharge number and power frequency voltage phase angle of the partial discharge signal based on each time point are compared with each of the defect characteristic information for similarity, including: Determine the amplitude-phase distribution similarity according to the signal amplitude, the power frequency voltage phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information, and determine the discharge number phase distribution similarity according to the discharge number, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information; The amplitude phase distribution similarity and the discharge number phase distribution similarity are respectively multiplied by corresponding preset weights and superimposed to obtain a comprehensive similarity.

3. The defect detection method during operation of a cable joint according to claim 2, characterized in that: The amplitude-phase distribution characteristic data includes a characteristic amplitude range and a corresponding phase angle distribution range, and the amplitude-phase distribution similarity is determined according to the signal amplitude, the power frequency voltage phase angle and the amplitude-phase distribution characteristic data in the defect characteristic information, including: Screening out each signal amplitude corresponding to the power frequency voltage phase angle within the phase angle distribution range, and determining it as the amplitude to be compared; Each of the amplitudes to be compared is compared with the characteristic amplitude range, the number of the amplitudes to be compared within the characteristic amplitude range is determined according to the comparison result, and the ratio of the number to the total number of the amplitudes to be compared is determined as the amplitude phase distribution similarity.

4. The method for detecting defects in the operation of a cable joint according to claim 2, characterized in that: The discharge number distribution characteristic data includes a characteristic discharge number range and a corresponding phase angle distribution range, and the determination of the discharge number phase distribution similarity according to the discharge number, the power frequency voltage phase angle and the discharge number distribution characteristic data in the defect characteristic information includes: Screening out each discharge number corresponding to the power frequency voltage phase angle within the phase angle distribution range, and determining it as the discharge number to be compared; Each of the discharge times to be compared is compared with the characteristic discharge times range, and the number of discharge times to be compared within the characteristic discharge times range is determined according to the comparison result, and the ratio of the number to the total number of discharge times to be compared is determined as the discharge times phase distribution similarity.

5. The method for detecting defects in the operation of a cable joint according to any one of claims 1 to 3, characterized in that: The step of determining a plurality of defects to be determined from the plurality of preset defects according to the similarity comparison processing result includes: The comprehensive similarities corresponding to the preset defects are arranged in descending order to obtain a similarity sequence, and the comprehensive similarities of a preset proportion of the similarity sequence are selected, and the preset defects corresponding to the selected comprehensive similarities are determined as defects to be determined.

6. The method for detecting defects in the operation of a cable joint according to any one of claims 1 to 3, characterized in that: The preset influencing parameter information includes influencing cable parameters and corresponding defect conditions, and determining the final defect based on the plurality of defects to be determined and the corresponding preset influencing parameter information includes: The monitoring values ​​of the influencing cable parameters corresponding to each of the defects to be determined within a preset time are obtained, and the final defect is determined based on the monitoring values ​​of each of the influencing cable parameters within the preset time and the corresponding defect conditions.

7. The method for detecting defects in the operation of a cable joint according to claim 6, characterized in that: The defect condition includes a defect monitoring value range and a defect change trend, and the final defect is determined based on the monitoring values ​​of each of the cable-affecting parameters within a preset time and the corresponding defect conditions, including: According to the monitoring values ​​of each of the cable-affecting parameters within a preset time, the corresponding average monitoring value and the monitoring value change trend are calculated respectively. When the average monitoring value is within the corresponding defect monitoring value range and the monitoring value change trend is the corresponding defect change trend, the corresponding defect to be determined is determined as the final defect.

8. A defect detection system for a cable joint during operation, characterized in that: include: A receiving module, used for receiving partial discharge information sent by a partial discharge monitoring device at every preset voltage cycle, wherein the partial discharge information includes a signal amplitude, a discharge number and a power frequency voltage phase angle of the partial discharge signal at each time point; An acquisition module, used to acquire multiple preset defects and corresponding defect feature information; A comparison processing module, used for performing similarity comparison processing with each defect feature information based on the signal amplitude, discharge times and power frequency voltage phase angle of the partial discharge signal at each time point; A to-be-determined defect determination module, used to determine a plurality of to-be-determined defects from a plurality of the preset defects according to the similarity comparison processing result; The acquisition module is further used to acquire preset influencing parameter information of a plurality of defects to be determined; The final defect determination module is used to determine the final defect based on the multiple defects to be determined and the corresponding preset influencing parameter information.

9. A defect detection device for a cable joint during operation, the device comprising: one or more processors; A storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the one or more processors implement the defect detection method during the operation of the cable joint as described in any one of claims 1-7.

10. A storage medium storing computer executable instructions, wherein the computer executable instructions, when executed by a computer processor, are used to perform the defect detection method during operation of a cable joint according to any one of claims 1 to 7.

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