System and method for extracting loop resistance characteristics of power cable whole-line grounding system

Abstract

The invention discloses a loop resistance feature extraction system and method for a power cable whole-line grounding system, and the system comprises a plurality of obtaining modules which are used for obtaining the resistance data of the grounding system and the environment resistivity characterization value of a corresponding position, and transmitting the resistance data and the corresponding environment resistivity characterization value to a processor; the processor is used for communicating with the plurality of acquisition modules and acquiring resistance characteristics of the grounding system based on the received resistance data of the same grounding system and the environment resistivity characterization value; wherein the resistance characteristic is used for evaluating the health state of the corresponding cable. By means of the mode, automatic data collection is achieved, interference of human factors is reduced, the accuracy of the data is improved, the actual state of the cable is accurately reflected by comprehensively considering the resistance data and the environment resistivity characterization value, and the accuracy of cable state evaluation is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power equipment maintenance applications, and in particular to a system and method for extracting loop resistance characteristics of a power cable full-line grounding system. Background Art

[0002] High-voltage power cables are an indispensable and important part of the power system. They bear the heavy responsibility of transmitting electric energy. Since cables are exposed to complex and changeable environments for a long time, such as underground, underwater, and tunnels, these environmental factors (such as temperature, humidity, corrosion, etc.) may affect the performance of cables. In addition, cables may also experience aging, wear, poor contact, and other problems during long-term use. Therefore, power supply companies need to regularly inspect high-voltage power cables.

[0003] When inspecting high-voltage power cables, it is necessary to evaluate the cable status. However, traditional maintenance inspection methods often rely on manual recording and analysis of data, which is not only time-consuming and labor-intensive, but also easily affected by the subjective factors of inspectors, leading to misjudgment and affecting the accuracy of cable status assessment.

[0004] Therefore, how to improve the accuracy of cable status assessment has become an important issue in the current power maintenance industry. Summary of the invention

[0005] The main technical problem solved by the present application is to provide a system and method for extracting loop resistance characteristics of a full-line grounding system of a power cable, which can improve the accuracy of cable status assessment.

[0006] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a loop resistance feature extraction system for the entire grounding system of a power cable, the system comprising a number of acquisition modules and a processor, the number of acquisition modules: used to obtain the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position, and send the resistance data and the corresponding environmental resistivity characterization value to the processor; the processor is used to communicate with the number of acquisition modules, and obtain the resistance characteristics of the cable grounding point based on the received resistance data and environmental resistivity characterization value of the same grounding system; wherein the resistance characteristics are used to evaluate the health status of the corresponding cable.

[0007] Preferably, several acquisition modules are respectively arranged at different grounding systems, and the acquisition modules include a data receiver, a resistance sensor and a resistivity tester; the data receiver is connected to the processor, the resistance sensor and the resistivity tester, and is used to control the resistance sensor and the resistivity tester to detect the resistance data and the environmental resistivity characterization value under the time conditions corresponding to the detection signal in response to receiving a trigger detection signal.

[0008] Preferably, the processor includes: a data preprocessing unit: used to remove noise from the received resistance data and environmental resistivity characterization values, and perform data cleaning on the resistance data and environmental resistivity characterization values ​​after noise removal; a preset feature extraction model: used to match corresponding model parameters based on the preprocessed environmental resistivity characterization values, and use the matched model parameters to set the feature extraction model to extract the resistance features in the preprocessed resistance data.

[0009] Preferably, the model parameters for matching the environmental resistance characterization value are obtained through training based on historical data; wherein the historical data includes resistance data measured under different environmental resistivity conditions and the corresponding cable health status.

[0010] Preferably, it also includes an evaluation module for matching a corresponding evaluation threshold based on the environmental resistance characterization value, and determining a resistance feature that meets the corresponding evaluation threshold as healthy, and determining a resistance feature that does not meet the corresponding evaluation threshold as unhealthy.

[0011] In order to solve the above-mentioned technical problems, another technical solution adopted in the present application is: to provide a method for extracting loop features of a power cable full-line grounding system, which is applied to any of the above-mentioned power cable full-line grounding system loop feature extraction systems, the method comprising: obtaining the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position; obtaining the resistance characteristics of the cable grounding point based on the resistance data and environmental resistivity characterization value of the same grounding system, wherein the resistance characteristics are used to evaluate the health status of the cable.

[0012] Preferably, obtaining the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position includes: in response to receiving a trigger detection signal, detecting the resistance data and the environmental resistivity characterization value under the time condition corresponding to the detection signal.

[0013] Preferably, obtaining the resistance characteristics of the cable grounding point based on the resistance data and the environmental resistivity characterization value of the same grounding system includes removing the noise of the resistance data and the environmental resistivity characterization value, and performing data cleaning on the resistance data and the environmental resistivity characterization value after the noise is removed; matching the corresponding model parameters based on the preprocessed environmental resistivity characterization value, and using the matched model parameters to set a preset feature extraction model to extract the resistance characteristics in the preprocessed resistance data.

[0014] Preferably, the model parameters for matching the environmental resistance characterization value are obtained through training based on historical data; wherein the historical data includes resistance data measured under different environmental resistivity conditions and the corresponding cable health status.

[0015] Preferably, after obtaining the resistance characteristics of the cable grounding point based on the resistance data and environmental resistivity characterization value of the same grounding system, the method also includes: matching the corresponding evaluation threshold based on the environmental resistance characterization value, and judging the resistance characteristics that meet the corresponding evaluation threshold as healthy, and judging the resistance characteristics that do not meet the corresponding evaluation threshold as unhealthy.

[0016] The beneficial effects of the present application are as follows: Different from the prior art, the present application obtains the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position through several acquisition modules. The processor communicates with the acquisition module, receives the data obtained by the acquisition module, and obtains the resistance characteristics based on these data. The resistance characteristics integrate the resistance data of the grounding system and the environmental resistivity characterization value, which is used to evaluate the health status of the cable. The use of an automated acquisition module to collect data reduces the interference of human factors and improves the accuracy of the data. Furthermore, by comprehensively considering the resistance data and the environmental resistivity characterization value, the actual status of the cable can be more accurately reflected, thereby improving the accuracy of the cable status assessment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the framework of an embodiment of a power cable full-line grounding system loop resistance feature extraction system of the present application.

[0018] Figure 2 It is a schematic diagram of the framework of another embodiment of the power cable full-line grounding system loop resistance feature extraction system of the present application.

[0019] Figure 3 It is a flow chart of an embodiment of a method for extracting loop resistance characteristics of a full-line grounding system of a power cable of the present application.

[0020] Figure 4 It is a flow chart of another embodiment of the method for extracting loop resistance characteristics of the full-line grounding system of a power cable of the present application. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present application. The terms "including" and "having" in the present application and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0022] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] See also Figure 1 , Figure 1 It is a schematic diagram of the framework of an embodiment of a power cable full-line grounding system loop resistance feature extraction system of the present application.

[0024] Specifically, the loop resistance of the cable grounding system will be affected by the environmental resistivity. The size of the soil resistivity depends on factors such as soil composition, humidity, and temperature. Generally speaking, the lower the soil resistivity, the smaller the grounding loop impedance (loop resistance) and the better the grounding effect. Because low-resistivity soil can provide better conductivity, it is easier for the grounding current to flow into the earth. Temperature also affects the resistivity of the soil. Generally speaking, rising temperatures will reduce the resistivity of water, which may affect the resistivity of the soil. When water in the soil freezes, the resistivity will increase significantly. Traditional cable health assessment methods often ignore the impact of changes in environmental resistivity, resulting in low accuracy in cable health assessment.

[0025] In this embodiment, the loop resistance feature extraction system 10 of the full-line grounding system of the power cable includes a plurality of acquisition modules 11 and a processor 12. The plurality of acquisition modules 11 are used to obtain the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position, and send the resistance data and the corresponding environmental resistivity characterization value to the processor 12; the processor 12 is used to communicate with the plurality of acquisition modules 11, and obtain the resistance feature of the cable grounding point based on the received resistance data and environmental resistivity characterization value of the same grounding system; wherein the resistance feature is used to evaluate the health status of the corresponding cable.

[0026] The above scheme obtains the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position through several acquisition modules 11. The processor 12 communicates with the acquisition module 11, receives the data obtained by the acquisition module 11, and obtains the resistance characteristics based on these data. The resistance characteristics integrate the resistance data of the grounding system and the environmental resistivity characterization value, which is used to evaluate the health status of the cable. The automated acquisition module 11 is used to collect data, which reduces the interference of human factors and improves the accuracy of the data. Furthermore, by comprehensively considering the resistance data and the environmental resistivity characterization value, the actual status of the cable can be more accurately reflected, thereby improving the accuracy of the cable status assessment.

[0027] In some embodiments, several acquisition modules 11 are respectively arranged at different grounding systems, and the acquisition modules 11 include a data receiver, a resistance sensor and a resistivity tester; the data receiver is connected to the processor 12, the resistance sensor and the resistivity tester, and is used to control the resistance sensor and the resistivity tester to detect the resistance data and the environmental resistivity characterization value under the time conditions corresponding to the detection signal in response to receiving a trigger detection signal.

[0028] Specifically, acquisition modules 11 are respectively set for different grounding systems to ensure that the data of each grounding system can be fully covered and accurately acquired. Each acquisition module 11 should include a calibrated and normally functioning data receiver, a resistance sensor and a resistivity tester, wherein the accuracy of the resistance sensor and the resistivity tester can be set according to actual needs. Data is transmitted between the data receiver and the processor 12 through a preset communication protocol.

[0029] In some application scenarios, when the system receives an inspection instruction, the processor 12 sends a trigger detection signal to each acquisition module 11. In some application scenarios, a preset inspection cycle may be set, and when the inspection cycle arrives, the processor 12 sends a trigger detection signal to each acquisition module 11.

[0030] Specifically, the time condition corresponding to the detection signal can be a time point, or a single time period, or several time periods with preset rules. The resistance data can be a resistance value, a resistance waveform in a certain time period, or an average value of resistance in a certain time period, or a resistance waveform in several time periods with preset rules. The environmental resistivity characterization value can be a resistivity value; or a relative resistivity, such as the ratio of the resistivity of the current environment to the preset resistivity, or a resistivity distribution map, etc. The data receiver transmits the collected resistance data and environmental resistivity characterization value to the processor 12 for further processing.

[0031] In some embodiments, the processor 12 includes: a data preprocessing unit: used to remove noise from the received resistance data and environmental resistivity characterization value, and perform data cleaning on the resistance data and environmental resistivity characterization value after the noise is removed; a preset feature extraction model: used to match the corresponding model parameters based on the preprocessed environmental resistivity characterization value, and use the matched model parameters to set the feature extraction model to extract the resistance features in the preprocessed resistance data. The model parameters matched with the environmental resistance characterization value are obtained based on historical data training; wherein the historical data includes resistance data measured under different environmental resistivity conditions and their corresponding cable health status.

[0032] Specifically, the noise in the received resistance data and environmental resistivity characterization value can be removed by using a Karl filter algorithm or a mean filter algorithm, and the data can be cleaned by checking and deleting duplicate data, missing data or abnormal data. The resistance data measured under different environmental resistivity conditions and their corresponding cable health status are collected to form a historical data set. The historical data set is trained using a machine learning algorithm to obtain a mapping relationship between the environmental resistivity characterization value and the model parameter time. When a new environmental resistivity characterization value is received, the trained mapping relationship is used to match the corresponding model parameter to set a feature extraction model, and feature extraction is performed on the preprocessed resistance data to obtain resistance features. In some specific embodiments, the resistance feature is one or more of the resistance change trend, resistance stability, resistance fluctuation range, etc.

[0033] In some embodiments, Figure 2 As shown, Figure 2 It is a framework diagram of another embodiment of the power cable full-line grounding system loop resistance feature extraction system of the present application. The power cable full-line grounding system loop resistance feature extraction system 20 can also include an evaluation module 23, which is used to match the corresponding evaluation threshold based on the environmental resistance characterization value, and judge the resistance feature that meets the corresponding evaluation threshold as healthy, and judge the resistance feature that does not meet the corresponding evaluation threshold as unhealthy.

[0034] Specifically, the evaluation threshold can be a threshold set in combination with historical data, empirical data and industry standards that can reflect the healthy state of the cable under different environmental resistivity conditions. The evaluation threshold can be set in an evaluation threshold table, which can be a pre-set table containing evaluation thresholds corresponding to different environmental resistance characterization values. The extracted resistance feature is compared with the matching evaluation threshold. If the resistance feature meets the requirements of the evaluation threshold, it is determined to be in a healthy state; if not, it is determined to be in an unhealthy state. Furthermore, an alarm module can be set. If the judgment result is an unhealthy state, an alarm mechanism is triggered to remind the user to further inspect and maintain.

[0035] The above scheme can obtain the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position in real time or on demand, and use the preset feature extraction model to match the corresponding model parameters based on the preprocessed environmental resistivity characterization value to extract the resistance features in the resistance data. According to the extracted resistance features and the corresponding environmental resistivity characterization value, the corresponding evaluation threshold is matched to determine the health status of the cable. Automatic detection and analysis of the loop resistance of the cable grounding system is realized, and the efficiency of cable maintenance is improved.

[0036] See also Figure 3 , Figure 31 is a flow chart of an embodiment of a method for extracting loop resistance characteristics of a power cable full-line grounding system of the present application. In this embodiment, the method comprises the following steps: S31: Obtain resistance data of the grounding system and environmental resistivity characterization values ​​of corresponding locations.

[0037] Specifically, acquisition modules can be set at various key locations of the power cable full-line grounding system. These modules include data receivers, resistance sensors and resistivity testers. The data receivers are connected to the processor, resistance sensors and resistivity testers. The resistance sensors are used to detect resistance data, and the resistivity testers are used to detect environmental resistivity characterization values. These devices should be calibrated and in normal working condition to ensure the accuracy of the data.

[0038] In some embodiments, obtaining resistance data of the grounding system and environmental resistivity characterization values ​​at corresponding locations includes: in response to receiving a trigger detection signal, detecting resistance data and environmental resistivity characterization values ​​under time conditions corresponding to the detection signal.

[0039] Specifically, the trigger detection signal can be sent by the processor according to a preset inspection cycle or a received inspection instruction. When the system receives an inspection instruction or reaches a preset inspection cycle, the processor sends a trigger detection signal to each acquisition module. After the data receiver in the acquisition module receives the trigger signal, the resistance sensor and the resistivity tester are controlled to start working to detect the resistance data and environmental resistivity characterization value under the corresponding time conditions. These data are then sent to the processor for further processing. The inspection cycle can be set according to the actual situation of the cable and maintenance requirements to ensure the timeliness and accuracy of the data.

[0040] The detection signal may include at least one time condition, and the time condition corresponding to the detection signal may be a time point, or a single time period, or several time periods with preset rules. The resistance data may be a resistance value, a resistance waveform within a certain time period, or an average value of resistance within a certain time period, or a resistance waveform within several time periods with preset rules. The environmental resistivity characterization value may be a resistivity value; or a relative resistivity, such as the ratio of the resistivity of the current environment to the preset resistivity, or a resistivity distribution map, etc. The data receiver transmits the collected resistance data and environmental resistivity characterization value to the processor for further processing.

[0041] S32: Obtain the resistance characteristics of the cable grounding point based on the resistance data and the environmental resistivity characterization value of the same grounding system, wherein the resistance characteristics are used to evaluate the health status of the cable.

[0042] By comprehensively considering the resistance data and the environmental resistivity characterization value, the actual status of the cable can be more accurately reflected, thereby improving the accuracy of cable status assessment.

[0043] In some embodiments, obtaining the resistance characteristics of the cable grounding point based on the resistance data and the environmental resistivity characterization value of the same grounding system includes removing noise from the resistance data and the environmental resistivity characterization value, and performing data cleaning on the resistance data and the environmental resistivity characterization value after the noise is removed; matching corresponding model parameters based on the preprocessed environmental resistivity characterization value, and using the matched model parameters to set a preset feature extraction model to extract the resistance characteristics in the preprocessed resistance data. The model parameters matched with the environmental resistance characterization value are obtained based on historical data training; wherein the historical data includes resistance data measured under different environmental resistivity conditions and their corresponding cable health status.

[0044] Specifically, the noise in the received resistance data and environmental resistivity characterization value can be removed by using a Karl filter algorithm or a mean filter algorithm, and the data can be cleaned by checking and deleting duplicate data, missing data or abnormal data. The resistance data measured under different environmental resistivity conditions and their corresponding cable health status are collected to form a historical data set. The historical data set is trained using a machine learning algorithm to obtain a mapping relationship between the environmental resistivity characterization value and the model parameter time. When a new environmental resistivity characterization value is received, the trained mapping relationship is used to match the corresponding model parameter to set a feature extraction model, and feature extraction is performed on the preprocessed resistance data to obtain resistance features. In some specific embodiments, the resistance feature is one or more of the resistance change trend, resistance stability, resistance fluctuation range, etc.

[0045] See also Figure 4 , Figure 4 It is a flow chart of another embodiment of the method for extracting loop resistance characteristics of the full-line grounding system of the power cable of the present application. Among them, steps S41 and S42 can refer to the above-mentioned S31 and S32, and will not be repeated here.

[0046] S43: Matching a corresponding evaluation threshold based on the environmental resistance characterization value, and determining a resistance feature that meets the corresponding evaluation threshold as healthy, and determining a resistance feature that does not meet the corresponding evaluation threshold as unhealthy.

[0047] Specifically, the evaluation threshold can be a threshold set in combination with historical data, empirical data and industry standards that can reflect the healthy state of the cable under different environmental resistivity conditions. The evaluation threshold can be set in an evaluation threshold table, which can be a pre-set table containing evaluation thresholds corresponding to different environmental resistance characterization values. The extracted resistance feature is compared with the matching evaluation threshold. If the resistance feature meets the requirements of the evaluation threshold, it is determined to be in a healthy state; if not, it is determined to be in an unhealthy state. Furthermore, an alarm module can be set. If the judgment result is an unhealthy state, an alarm mechanism is triggered to remind the user to further inspect and maintain.

[0048] The above scheme can obtain the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position in real time or on demand, and use the preset feature extraction model to match the corresponding model parameters based on the preprocessed environmental resistivity characterization value to extract the resistance features in the resistance data. According to the extracted resistance features and the corresponding environmental resistivity characterization value, the corresponding evaluation threshold is matched to determine the health status of the cable. Automatic detection and analysis of the loop resistance of the cable grounding system is realized, and the efficiency of cable maintenance is improved.

[0049] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A loop resistance feature extraction system for a power cable full-line grounding system, characterized in that: include: Several acquisition modules: used for acquiring the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position, and sending the resistance data and the corresponding environmental resistivity characterization value to the processor; The processor is used to communicate with the plurality of acquisition modules, and acquire the resistance characteristics of the grounding system based on the received resistance data and the environmental resistivity characterization value of the same grounding system; The resistance characteristic is used to evaluate the health status of the corresponding cable.

2. The loop resistance feature extraction system for the full-line grounding system of power cable according to claim 1 is characterized in that: Several acquisition modules are respectively arranged at different grounding systems, and the acquisition modules include a data receiver, a resistance sensor and a resistivity tester; The data receiver is connected to the processor, the resistance sensor and the resistivity tester, and is used to control the resistance sensor and the resistivity tester to detect the resistance data and the environmental resistivity characterization value under the time conditions corresponding to the detection signal in response to receiving a trigger detection signal.

3. The loop resistance feature extraction system for the full-line grounding system of power cables according to claim 1 is characterized in that: The processor comprises: A data preprocessing unit: used to remove noise from the received resistance data and environmental resistivity characterization value, and perform data cleaning on the resistance data and environmental resistivity characterization value after the noise is removed; Preset feature extraction model: used to match corresponding model parameters based on the preprocessed environmental resistivity characterization value, and use the matched model parameters to set the feature extraction model to extract resistance features in the preprocessed resistance data.

4. The loop resistance feature extraction system for the full-line grounding system of power cables according to claim 3 is characterized in that: The model parameters for matching the environmental resistance characterization value are obtained through training based on historical data; wherein the historical data includes resistance data measured under different environmental resistivity conditions and the corresponding cable health status.

5. The loop resistance feature extraction system for the full-line grounding system of a power cable according to claim 3 or 4, characterized in that: It also includes an evaluation module, which is used to match the corresponding evaluation threshold based on the environmental resistance characterization value, and judge the resistance characteristics that meet the corresponding evaluation threshold as healthy, and judge the resistance characteristics that do not meet the corresponding evaluation threshold as unhealthy.

6. A method for extracting loop resistance characteristics of a power cable full-line grounding system, applied to a power cable full-line grounding system loop characteristics extraction system as described in any one of claims 1 to 5, characterized in that: The method comprises: Obtaining resistance data of the grounding system and environmental resistivity characterization values ​​of corresponding locations; The resistance characteristic of the cable grounding point is obtained based on the resistance data and the environmental resistivity characterization value of the same grounding system, wherein the resistance characteristic is used to evaluate the health status of the cable.

7. The method for extracting loop resistance characteristics of a power cable full-line grounding system according to claim 6 is characterized in that: The obtaining of the resistance data of the grounding system and the environmental resistivity characterization value of the corresponding position comprises: In response to receiving a trigger detection signal, resistance data and an environmental resistivity characterization value under a time condition corresponding to the detection signal are detected.

8. The method for extracting loop resistance characteristics of a power cable full-line grounding system according to claim 6 is characterized in that: The obtaining of the resistance characteristics of the cable grounding point based on the resistance data and the environmental resistivity characterization value of the same grounding system includes: removing noise from the resistance data and the environmental resistivity characterization value, and performing data cleaning on the resistance data and the environmental resistivity characterization value after the noise is removed; The corresponding model parameters are matched based on the preprocessed environmental resistivity characterization value, and a preset feature extraction model is set using the matched model parameters to extract the resistance features in the preprocessed resistance data.

9. The method for extracting loop resistance characteristics of a power cable full-line grounding system according to claim 8 is characterized in that: The model parameters for matching the environmental resistance characterization value are obtained through training based on historical data; wherein the historical data includes resistance data measured under different environmental resistivity conditions and the corresponding cable health status.

10. The method for extracting loop resistance characteristics of a power cable full-line grounding system according to claim 9 is characterized in that: After obtaining the resistance characteristics of the cable grounding point based on the resistance data and the environmental resistivity characterization value of the same grounding system, the method further includes: Based on the matching of the environmental resistance characterization value with the corresponding evaluation threshold, the resistance characteristic that meets the corresponding evaluation threshold is determined to be healthy, and the resistance characteristic that does not meet the corresponding evaluation threshold is determined to be unhealthy.

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