High-voltage insulator leakage current on-line monitoring system and method

Abstract

The invention discloses a high-voltage insulator leakage current on-line monitoring system and method, relates to an image optimization technology, is used for improving electric leakage caused by false resistance of cooling dirt after a high-voltage insulator is damaged due to stress, and comprises the steps of obtaining the position and breakdown current magnitude of each part of the voltage insulator, and measuring the toughness of each part of the voltage insulator. Analyzing an external force bearing interval of each part of the voltage insulator; collecting vibration data and sound data of the voltage insulator, and judging stress distribution of the voltage insulator; matching and calibrating the stress distribution of the voltage insulator and the partial position, marking, calculating the damage amount of the marked position, and obtaining the dielectric strength of the material of all parts of the voltage insulator in the marked position; different processing modes are selected to process the dielectric strength of the material according to the number of the parts of the voltage insulator in the marked position to obtain a marked feature value, and whether electric leakage detection is carried out on the voltage insulator or not is judged according to the marked position damage amount and the marked feature value.

Description

Technical Field

[0001] The present invention relates to the technical field of leakage detection, and more specifically, to an online monitoring system and method for leakage current of high-voltage insulators. Background Art

[0002] Leakage detection technology is a technology used to identify leakage phenomena in electrical equipment or circuits. When applied to an online monitoring system for high-voltage insulators, it can detect and alarm the leakage phenomenon on the surface of high-voltage insulators in real time, reducing the leakage risk.

[0003] The prior art has the following deficiencies:

[0004] Traditional high-voltage insulators rely on an insulation resistance testing instrument to measure the resistance value of the insulator and then judge whether its insulation performance meets the standard. However, when there is cooling dirt on the surface crack of the insulator, the resistance value will also increase. When powered on, the cooling dirt at the crack is likely to melt, resulting in a rapid drop in resistance. When the high-voltage insulator is damaged on the surface due to physical external force, leakage is likely to occur. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides an online monitoring system and method for leakage current of high-voltage insulators. By analyzing the external force bearing intervals of various parts of the high-voltage insulator, combining the force distribution and property strength of the high-voltage insulator, the damage amount of each part is analyzed and it is judged whether to perform leakage detection to solve the problems raised in the above background art.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An online monitoring method for leakage current of high-voltage insulators, comprising the following steps:

[0008] Step S1: Call the equipment file of the voltage insulator to obtain the positions and breakdown current amounts of various parts of the voltage insulator, measure the toughness of various parts of the voltage insulator, and analyze the external force bearing intervals of various parts of the voltage insulator by combining the breakdown current amount and the part toughness;

[0009] Step S2: Obtain the vibration data and sound data of the voltage insulator through a vibration sensor and a sound sensor respectively, and judge the force distribution of the voltage insulator by combining the vibration data and the sound data;

[0010] Step S3: Match and calibrate the force distribution of the voltage insulator with some positions and then mark it. Calculate the damage amount at the marked position by the force distribution and external force bearing interval at the marked position, and obtain the material dielectric strength of all parts of the voltage insulator within the marked position;

[0011] Step S4: Select different processing methods according to the number of parts of the voltage insulator within the marked position to process the dielectric strength of the material to obtain marked characteristic values, and comprehensively judge whether to perform a leakage detection on the voltage insulator based on the damage amount at the marked position and the marked characteristic values.

[0012] In a preferred embodiment, in step S1, obtain the position data of each part and the breakdown current of the voltage insulator through the equipment file of the voltage insulator. The position data includes the precise three-dimensional space coordinates of each functional component of the voltage insulator; the breakdown current is the minimum current value when irreversible breakdown occurs on the surface or inside of the insulator.

[0013] In a preferred embodiment, in step S1, when the external force borne by each part of the voltage insulator exceeds the preset deviation of the ultimate toughness and the current is lower than the breakdown current, it is judged as the safe interval for external force bearing; when the external force borne by each part of the voltage insulator exceeds the ultimate toughness or exceeds the breakdown current, it is judged as the failure interval for external force bearing; otherwise, it is judged as the warning interval for external force bearing;

[0014] The ultimate toughness is the ultimate external force that the corresponding part of the voltage insulator can withstand when cracks appear.

[0015] In a preferred embodiment, in step S2, the vibration data and the sound data are respectively the vibration signal characteristics and the sound emission characteristics collected by the vibration sensor and the sound sensor. The vibration signal characteristics and the sound emission characteristics are respectively the vibration amplitude and the sound wave intensity; after standardizing the vibration signal characteristics and the sound emission characteristics, calculate the comprehensive force value of each part position of the voltage insulator by the geometric mean method. The calculation formula is: , where D is the result after standardizing the vibration signal characteristic value, and E is the result after standardizing the sound emission characteristic value.

[0016] In a preferred embodiment, in step S3, retrieve the three-dimensional coordinates of each part of the insulator, and establish the corresponding relationship between the names of each part of the voltage insulator and the three-dimensional space coordinates; calculate the radial distance from the stress distribution data coordinates to the central axis , where x and y are the horizontal and vertical coordinate values of the stress distribution data, and r is the distance from the coordinate point to the central axis;

[0017] Obtain the stress distribution of the high-voltage insulator according to r, proofread the preset positions of each part of the electronic insulator, and mark the parts of the voltage insulator whose positions are within the stress distribution.

[0018] In a preferred embodiment, in step S3, the damage amount is an index value reflecting the degree of external force damage at the marked position. When the comprehensive force value is less than the upper limit of the safe interval, the damage amount is set to 0;

[0019] When the comprehensive stress value is within the warning range, calculate the damage amount through the damage amount calculation formula: , where the upper limit of the safety range is the preset deviation of the stress value of each part of the insulator not exceeding its ultimate toughness; when the stress value exceeds the failure range, the damage amount is set to 1.

[0020] In a preferred embodiment, in step S3, obtain the dielectric strength of the material corresponding to the marked position. For the parts marked as the warning range or the failure range, record the breakdown voltage. The dielectric strength is the breakdown voltage of this part divided by the thickness of the material of this part;

[0021] After matching and calibrating the stress distribution of the voltage insulator with the part position and marking, use the stress distribution at the marked position and the external force bearing range to calculate the damage amount at the marked position, and at the same time obtain the dielectric strength of all parts of the voltage insulator within the marked position.

[0022] In a preferred embodiment, in step S4, if the marked position is a single part of the voltage insulator, use the measured value of the dielectric strength of this part as the marked characteristic value, and obtain that the marked characteristic value is equal to the dielectric strength; if the marked position includes multiple parts of the voltage insulator, then use the weighted average method to generate the marked characteristic value, and the calculation formula is: , where S is the marked characteristic value, is the dielectric strength of the i-th part, is the stress correction coefficient;

[0023] The stress correction coefficient reflects the influence of stress on the insulation performance, and different stress correction coefficients are set according to the stress range.

[0024] In a preferred embodiment, in step S4, comprehensively analyze whether to perform leakage monitoring through the damage amount and the marked characteristic value at the marked position:

[0025] When the damage amount range at the marked position passes the preset damage amount threshold, divide it into a high damage area; otherwise, divide it into a low damage area;

[0026] When the marked characteristic value range passes the preset insulation threshold, divide it into a high insulation area; otherwise, divide it into a low insulation area;

[0027] When the damage amount at the marked position is in the low damage area and the marked characteristic value is in the high insulation area, no leakage detection is performed; when the damage amount at the marked position is in the high damage area or the marked characteristic value is in the low insulation area, leakage detection is performed.

[0028] A high-voltage insulator leakage current online monitoring system for implementing the above-mentioned high-voltage insulator leakage current online monitoring method, including a data acquisition module, a force distribution module, a performance evaluation module, and a leakage detection module;

[0029] The data acquisition module is used to retrieve the three-dimensional coordinates, dielectric strength, and breakdown current of the voltage insulator collected from the equipment file; collect the signal data of the vibration sensor and the sound sensor; detect and analyze the toughness of each part, and transmit it to the subsequent module for the normal operation of the system;

[0030] The force distribution module comprehensively analyzes the external force bearing range of each part based on the breakdown current and the toughness of each part; generates a comprehensive force value by analyzing the signal data, obtains the force distribution of the voltage insulator, and transmits the force distribution and the external force bearing range of each part to the performance evaluation module;

[0031] The performance evaluation module calibrates and matches the marked position based on the force distribution and the three-dimensional coordinates of the voltage insulator, analyzes the damage amount of the marked position in combination with the external force bearing range of each part, and transmits it to the leakage detection module;

[0032] The leakage detection module combines the dielectric strength to comprehensively analyze whether to perform leakage detection based on the marked characteristic value and the damage amount of the marked position.

[0033] The technical effects and advantages of the high-voltage insulator leakage current online monitoring system and method of the present invention:

[0034] The present invention obtains the positions and breakdown currents of each part of the voltage insulator, measures the toughness of each part of the voltage insulator, comprehensively analyzes the external force bearing range of each part of the voltage insulator based on the breakdown current and the toughness of the part; collects the vibration data and sound data of the voltage insulator, and comprehensively judges the force distribution of the voltage insulator based on the vibration data and the sound data; matches and calibrates the force distribution of the voltage insulator with some positions and then marks, calculates the damage amount of the marked position through the force distribution and the external force bearing range of the marked position, performs force analysis on each part separately, reduces the material analysis error of crack generation caused by material differences in different parts, and obtains the material dielectric strength of all parts of the voltage insulator within the marked position; selects different processing methods to process the material dielectric strength according to the number of parts of the voltage insulator within the marked position to obtain the marked characteristic value, and comprehensively judges whether to perform leakage detection on the voltage insulator based on the damage amount of the marked position and the marked characteristic value, realizing the accurate detection and hierarchical early warning of the leakage current of the high-voltage insulator, improving the detection efficiency and reliability, and at the same time reducing the operation and maintenance cost and safety risk. Brief Description of the Drawings

[0035] Figure 1 It is a schematic diagram of a high-voltage insulator leakage current online monitoring method of the present invention.

[0036] Figure 2 This is a flow chart of an on-line monitoring system for the leakage current of a high-voltage insulator according to the present invention. Specific embodiments

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] The present invention obtains the positions of various parts of the voltage insulator and the breakdown current, measures the toughness of various parts of the voltage insulator, and analyzes the external force bearing intervals of various parts of the voltage insulator by integrating the breakdown current and the toughness of the parts; collects the vibration data and sound data of the voltage insulator, and judges the force distribution of the voltage insulator by integrating the vibration data and sound data; matches and calibrates the force distribution of the voltage insulator with some positions and then marks it, calculates the damage amount of the marked position through the force distribution and the external force bearing interval of the marked position, and obtains the material dielectric strength of all parts of the voltage insulator within the marked position; selects different processing methods according to the number of parts of the voltage insulator within the marked position to process the material dielectric strength to obtain the marked characteristic value, and judges whether to perform leakage detection on the voltage insulator by integrating the damage amount of the marked position and the marked characteristic value, realizing the accurate detection and hierarchical early warning of the leakage current of the high-voltage insulator, improving the detection efficiency and reliability, and at the same time reducing the operation and maintenance cost and safety risk.

[0039] Embodiment 1, an on-line monitoring method for the leakage current of a high-voltage insulator, as Figure 1 shown, includes the following steps:

[0040] Step S1: Call the equipment file of the voltage insulator to obtain the positions of various parts of the voltage insulator and the breakdown current, measure the toughness of various parts of the voltage insulator, and analyze the external force bearing intervals of various parts of the voltage insulator by integrating the breakdown current and the toughness of the parts;

[0041] Step S2: Respectively obtain the vibration data and sound data of the voltage insulator through a vibration sensor and a sound sensor, and judge the force distribution of the voltage insulator by integrating the vibration data and sound data;

[0042] Step S3: Match and calibrate the force distribution of the voltage insulator with some positions and then mark it, calculate the damage amount of the marked position through the force distribution and the external force bearing interval of the marked position, and obtain the material dielectric strength of all parts of the voltage insulator within the marked position;

[0043] Step S4: Select different processing methods according to the number of parts of the voltage insulator within the marked position to process the dielectric strength of the material to obtain the marked characteristic value, and comprehensively judge whether to perform a leakage detection on the voltage insulator based on the damage amount at the marked position and the marked characteristic value.

[0044] The specific implementation is as follows:

[0045] In step S1, obtain the position data and breakdown current of each part of the voltage insulator through the equipment file of the voltage insulator. The position data includes the precise three-dimensional space coordinates of each functional component of the voltage insulator. The breakdown current is the minimum current value when irreversible breakdown occurs on the surface or inside of the insulator.

[0046] Detect the toughness of each part of the voltage insulator by the ultrasonic pulse echo method. Touch the surface of the measurement part of the voltage insulator, emit ultrasonic waves, and record the echo signals, including the initial pulse, bottom echo, and defect echo. The formula for calculating the sound velocity is: , where d is the thickness of the measurement position, and is the time difference between the bottom echo and the initial pulse, and v is the sound velocity. The formula for calculating the attenuation coefficient is: , where, and are the amplitudes of the initial pulse and the bottom echo, is the attenuation coefficient.

[0047] The relationship formula between the sound velocity, attenuation coefficient, and toughness is: , where, is the toughness, and a, b, and c are coefficients whose values need to be determined through regression analysis.

[0048] If each part of the voltage insulator withstands an external force exceeding the preset deviation of the ultimate toughness, and at the same time the current is lower than the breakdown current, it is judged as the safe interval for external force bearing; if each part of the voltage insulator withstands an external force exceeding the ultimate toughness or exceeding the breakdown current, it is judged as the failure interval for external force bearing; otherwise, it is judged as the warning interval for external force bearing.

[0049] For example, the design specification in the power industry requires that the safety factor of the voltage insulator ≥ 1.43. The formula for the safety factor is: , According to the quantitative design idea of the safety margin, if each part of the voltage insulator withstands an external force less than 70% of the ultimate toughness, and at the same time the current is less than 70% of the breakdown current, it is judged as the safe interval for external force bearing; if each part of the voltage insulator withstands an external force greater than 70% and less than the ultimate toughness, or the current is greater than 70% and less than the breakdown current, it is judged as the warning interval for external force bearing; if each part of the voltage insulator withstands an external force exceeding the ultimate toughness or exceeding the breakdown current, it is judged as the failure interval for external force bearing.

[0050] The non-destructive testing technology of ultrasonic pulse echo method measures the toughness of each part of the insulator. By analyzing the quantitative relationship between the sound velocity, attenuation coefficient and toughness, and combining the power industry specifications with the stress range, the external force bearing range division based on the toughness of the voltage insulator and the breakdown current is obtained. The division of the safe range provides a quantitative standard for judging the damage amount and insulation strength in the following text.

[0051] It should be noted that the equipment files of voltage insulators are stored in the power asset management system, including the full life cycle data of the insulators, such as the three-dimensional structure parameters and material composition parts at the time of factory to the historical operation data. The ultrasonic pulse echo method is a non-destructive testing technology using a portable ultrasonic flaw detector. The basic principle is to emit ultrasonic pulses into the material and receive the reflected sound waves, and measure the material properties by analyzing the time and amplitude of the echo. The ultimate load refers to the maximum load that a voltage insulator can withstand under specific conditions. Once this load is exceeded, the performance and structural integrity of the insulator may be severely affected. The equipment files of voltage insulators are stored in the power asset management system, including the ultimate load information of each part of the insulator. Both the ultimate load and the ultimate toughness are related to the ability of the insulator to withstand external forces. The ultimate load is measured from the perspective of overall load bearing, and the ultimate toughness is the ability of the material itself to resist deformation and fracture.

[0052] In step S2, the three-dimensional coordinates marked in the equipment file accurately locate the surface of the voltage insulator. The vibration sensor and the sound sensor are distributed on the surfaces at different positions within the stress range, and the vibration signal characteristics and sound emission characteristics are extracted for the coordinates at the same position. The vibration signal characteristics and the sound emission characteristics are the vibration amplitude and the sound wave intensity respectively; the vibration signal characteristics and the sound emission characteristics are normalized.

[0053] Normalization is performed through the Max-Min normalization algorithm: , where is the vibration signal characteristic value or sound emission characteristic value extracted, is the minimum value of the vibration signal characteristic or sound emission characteristic, is the maximum value of the vibration signal characteristic value or sound emission characteristic value, is the result after normalization of the corresponding vibration signal characteristic value or sound emission characteristic value; both the vibration signal characteristic value and the sound emission characteristic value are compressed into the interval of 0 to 1. Further, the geometric mean method is used to calculate all the characteristic values of vibration and sound waves to obtain the comprehensive stress value at this position. The calculation formula is: , where D is the result after normalization of the vibration signal characteristic value, and E is the result after normalization of the sound emission characteristic value; within a stress range, the set of comprehensive stress values calculated at each different position is the stress distribution data of the voltage insulator.

[0054] Vibration data and sound data are respectively obtained through a vibration sensor and a sound sensor. The extracted vibration signal features and sound emission features are normalized using the Max - Min normalization algorithm, compressing all features into the range of 0 to 1. Then, the geometric mean method is used to calculate the comprehensive force value of the normalized features, and further the force distribution of the voltage insulator is judged. This force distribution is the data for position matching of the following parts.

[0055] It should be noted that a vibration sensor is a device that converts mechanical vibration into an electrical signal. When it is installed on a voltage insulator, when the insulator is subjected to an external force and vibrates, the vibration sensor converts the vibration into vibration data in the form of an electrical signal; the sound sensor converts the sound signal into an electrical signal. When the voltage insulator is stressed, it may generate sounds due to changes in its internal structure or interaction with the surrounding environment. The sound sensor can capture these sounds and convert them into electrical signals that can be processed, thereby obtaining sound data; the geometric mean method is used to calculate the average value of a set of positive data and is applicable to processing data with a product relationship or a proportional relationship. In the high - voltage insulator system, combining the two indicators of the vibration signal characteristic value or the sound emission characteristic value, the comprehensive force value of this position is calculated.

[0056] In step S3, through the three - dimensional coordinates of each part of the insulator in the equipment file, the corresponding relationship between the name of each part of the voltage insulator and the three - dimensional space coordinates is established. For example, the coordinate range of the skirt root is , and the coordinate position of each force distribution data . According to the structural characteristics of the voltage insulator, the z - axis in the vertical direction is divided into multiple regions. For example, the bottom fitting connection section is at a lower height, the middle is the core rod main body and the surrounding skirt group, and the top is the fitting section connected to the wire. Through the z - coordinate of the force distribution data coordinate, it is judged which part of the voltage insulator it belongs to. For example, if the z - coordinate of the force distribution data coordinate is within the middle range of the voltage insulator, it is judged to belong to the core rod or skirt part. Further, by calculating the radial distance from the force distribution data coordinate to the central axis , where x and y are the horizontal and vertical coordinate values of the force distribution data, and r is the distance from the coordinate point to the central axis.

[0057] For example, if the r value is less than the radius of the core rod, it is judged as the core rod component. For the force range, different force distribution data are marked with positions to judge which part of the voltage insulator this force range is in.

[0058] A circle is obtained according to r to get the force distribution of the high - voltage insulator, and the preset positions of each part of the electronic insulator are calibrated. The parts of the voltage insulator whose positions are within the force distribution are marked.

[0059] The damage amount is an indicator reflecting the degree of external force damage to the marked position. When the comprehensive force value is less than the upper limit of the safe range, the damage amount is 0. When the comprehensive force value is within the warning range, the calculation formula for the damage amount is: , where the upper limit of the safe range is that the force value of each part of the insulator does not exceed 70% of its ultimate toughness. When the force value exceeds the failure range, the damage amount is 1. The force value of the voltage insulator is detected and obtained by the pressure sensor at the corresponding part position.

[0060] Obtain the dielectric strength of the material corresponding to the marked position through the equipment file of the voltage insulator. For the parts marked as the warning range or the failure range, measure the breakdown voltage in real time through a dielectric strength tester and record it. The dielectric strength is the breakdown voltage of this part divided by the thickness of the material of this part.

[0061] Match and calibrate the force distribution of the voltage insulator with the part position and mark it. Using the force distribution at the marked position and the external force bearing range, calculate the damage amount at the marked position, and at the same time obtain the dielectric strength of all parts of the voltage insulator within the marked position. The damage amount and dielectric strength data at the marked position provide double quantitative indicators for the final decision.

[0062] It should be noted that the dielectric strength is an inherent electrical property of the insulating material itself, indicating the ability of the material to resist breakdown under the action of an electric field. It is determined through standard tests during factory production and recorded in the equipment file.

[0063] In step S4, if the marked position of the voltage insulator is a single part, use the measured value of the dielectric strength of the material of this part as the marked characteristic value, and obtain that the marked characteristic value is equal to the dielectric strength. If the marked position includes multiple parts of the voltage insulator, different weights are assigned according to different parts. For example, a high weight coefficient is assigned to the core load-bearing part, and a low weight coefficient is assigned to the vulnerable and weak parts.

[0064] Furthermore, the weighted average method is used to generate the marked characteristic value, and the calculation formula is: , where S is the marked characteristic value, is the dielectric strength of the i-th part, is the force correction coefficient, which reflects the influence of force on the insulation performance, and different coefficients are assigned in different ranges of force. For example, when the force is within the safe range, the force correction coefficient has a value of 1. When the force is within the warning range, the force correction coefficient has a value from 0.9 to 0.7. When the force is within the failure range, has a value less than 0.6;

[0065] The marked characteristic value is an insulation strength index, reflecting the comprehensive insulation ability of the marked position under the current stress state: the larger the marked characteristic value, the better the insulation strength and the lower the leakage risk. The smaller the marked characteristic value, the worse the insulation strength, and leakage detection should be prioritized.

[0066] Through a two-dimensional threshold matrix decision model, the damage amount and marked characteristic value at the marked position are comprehensively analyzed to determine whether to conduct leakage monitoring. The damage amount and marked characteristic value at the marked position are each divided into regions with clear threshold boundaries to comprehensively judge whether to conduct leakage detection on the voltage insulator.

[0067] When the damage amount range at the marked position passes the preset damage amount threshold, it is divided into a high-damage region; otherwise, it is divided into a low-damage region;

[0068] When the marked characteristic value range passes the preset insulation threshold, it is divided into a high-insulation region; otherwise, it is divided into a low-insulation region;

[0069] When the damage amount at the marked position is in the low-damage region and the marked characteristic value is in the high-insulation region, no leakage detection is conducted; when the damage amount at the marked position is in the high-damage region or the marked characteristic value is in the low-insulation region, leakage detection is conducted.

[0070] Within the marked position, different processing methods are selected according to the number of parts of the voltage insulator to process the dielectric strength, and the marked characteristic value reflecting the insulation strength of the marked position is obtained. Based on the damage amount at the marked position and the obtained marked characteristic value, it is judged whether to conduct leakage detection on the voltage insulator.

[0071] It should be noted that the insulation strength is the comprehensive insulation ability of the insulation material or structure under the actual operating state, reflecting its ability to withstand the electric field, and needs to be calculated by combining the dielectric strength with a correction factor. The two-dimensional threshold matrix decision model is a matrix-based decision-making method based on two key parameters. The definitions and ranges of these two parameters need to be clarified, and through clear threshold boundaries, a quantitative judgment on whether leakage detection is required for the high-voltage insulator is achieved.

[0072] Embodiment 2, a high-voltage insulator leakage current on-line monitoring system, as Figure 2 shown, for implementing a high-voltage insulator leakage current on-line monitoring method, including a data acquisition module, a stress distribution module, a performance evaluation module, and a leakage detection module.

[0073] The functions of each module are as follows:

[0074] The data acquisition module is used to retrieve the three-dimensional coordinates, dielectric strength, and breakdown current of the voltage insulator collected from the equipment file; collect the signal data of the vibration sensor and the sound sensor; detect and analyze the toughness of each part. Provide data for the subsequent modules.

[0075] The force distribution module analyzes the external force bearing intervals of each part by comprehensively considering the breakdown current and the toughness of each part; generates a comprehensive force value by analyzing the signal data, obtains the force distribution of the voltage insulator, and inputs the force distribution and the external force bearing intervals of each part into the performance evaluation module.

[0076] The performance evaluation module calibrates and matches the marked positions based on the force distribution and the three-dimensional coordinates of the voltage insulator, analyzes the damage amount at the marked positions in combination with the external force bearing intervals of each part, and inputs it into the leakage detection module.

[0077] The leakage detection module comprehensively analyzes whether to perform leakage detection by combining the dielectric strength to generate the marked feature value and the damage amount at the marked positions.

[0078] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product.

[0079] Those of ordinary skill in the art can realize that the modules and algorithm steps of each example described in combination with the embodiments disclosed in this article can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application of the technical solution and the invention constraints. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0080] In addition, the functional modules in each embodiment of this application can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module.

[0081] As mentioned above, this is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claimed rights.

[0082] Finally: The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An on-line monitoring method for the leakage current of a high-voltage insulator, characterized in that, It includes the following steps: Step S1: Call the equipment file of the voltage insulator to obtain the positions of all parts of the voltage insulator and the breakdown current, measure the toughness of all parts of the voltage insulator, and analyze the external force bearing range of all parts of the voltage insulator by combining the breakdown current and the toughness of the parts; Step S2: Obtain the vibration data and sound data of the voltage insulator through a vibration sensor and a sound sensor respectively, and judge the force distribution of the voltage insulator by combining the vibration data and the sound data; Step S3: Match and calibrate the force distribution of the voltage insulator with the positions of all parts and then mark it. Calculate the damage amount at the marked position based on the force distribution and the external force bearing range at the marked position, and obtain the dielectric strength of all materials of the voltage insulator within the marked position; Step S4: Select different processing methods according to the number of parts of the voltage insulator within the marked position to process the dielectric strength to obtain the marked characteristic value, and judge whether to perform leakage detection on the voltage insulator by combining the damage amount at the marked position and the marked characteristic value.

2. A method for on-line monitoring of leakage current of a high-voltage insulator according to claim 1, characterized in that: In step S1, the position data of all parts of the voltage insulator and the breakdown current are obtained through the equipment file of the voltage insulator. The position data includes the precise three-dimensional space coordinates of all functional parts of the voltage insulator; the breakdown current is the minimum current value when irreversible breakdown occurs on the surface or inside of the insulator.

3. A method for on-line monitoring of leakage current of a high-voltage insulator according to claim 1, characterized in that: In step S1, when the external force borne by each part of the voltage insulator exceeds the preset deviation of the ultimate toughness and the current is lower than the breakdown current, it is judged as the safe range of external force bearing; when the external force borne by each part of the voltage insulator exceeds the ultimate toughness or exceeds the breakdown current, it is judged as the failure range of external force bearing; otherwise, it is judged as the warning range of external force bearing; The ultimate toughness is the ultimate external force that the corresponding part of the voltage insulator can withstand when cracks appear.

4. A method for on-line monitoring of leakage current of a high-voltage insulator according to claim 1, characterized in that: In step S2, the vibration data and the sound data are respectively the vibration signal features and the sound emission features collected by the vibration sensor and the sound sensor. The vibration signal feature and the sound emission feature are respectively the vibration amplitude and the sound wave intensity. After standardizing the vibration signal feature and the sound emission feature, the comprehensive force value of each part of the voltage insulator is calculated by the geometric mean method, and the calculation formula is: , where D is the result after standardizing the vibration signal feature value, and E is the result after standardizing the sound emission feature.

5. A method for on-line monitoring of leakage current of a high-voltage insulator according to claim 4, characterized in that: In step S3, the three-dimensional coordinates of each part of the insulator are retrieved, and the corresponding relationship between the names of each part of the voltage insulator and the three-dimensional space coordinates is established; by calculating the radial distance from the coordinates of the force distribution data to the central axis , where x and y are the horizontal and vertical coordinate values of the force distribution data, and r is the distance from the coordinate point to the central axis; Obtain the force distribution of the high-voltage insulator by making a circle according to r, proofread the preset positions of all parts of the electronic insulator, and mark the parts of the voltage insulator whose positions are within the force distribution.

6. A method for on-line monitoring of leakage current of a high-voltage insulator according to claim 3, characterized in that: In step S3, the damage amount is an index value reflecting the degree of external force damage at the marked position. When the combined force value is less than the upper limit of the safe range, the damage amount is set to 0; When the comprehensive stress value is within the warning range, calculate the damage amount through the damage amount calculation formula: , where the upper limit of the safety range is the preset deviation of the stress value of each part of the insulator not exceeding its ultimate toughness; when the stress value exceeds the failure range, the damage amount is set to 1; The force value of the voltage insulator is detected and obtained by a pressure sensor at the corresponding part position.

7. A method for on-line monitoring of leakage current of a high-voltage insulator according to claim 1, characterized in that: In step S3, obtain the dielectric strength of the material corresponding to the marked position. For the parts marked as the warning range or the failure range, record the breakdown voltage, and the dielectric strength is the breakdown voltage of this part divided by the thickness of this part of the material; After the force distribution of the voltage insulator is calibrated and marked to match the position, the damage amount at the marked position is calculated using the force distribution at the marked position and the external force bearing range, and at the same time, the material dielectric strength of all parts of the voltage insulator within the marked position is obtained.

8. A method for on-line monitoring of leakage current of high-voltage insulators according to claim 7, characterized in that: In step S4, when the marked position is a single part of the voltage insulator, the measured value of the material dielectric strength of this part is used as the marked characteristic value, and it is obtained that the marked characteristic value is equal to the dielectric strength; when the marked position includes multiple parts of the voltage insulator, the weighted average method is used to generate the marked characteristic value, and the calculation formula is: , where S is the marked characteristic value, is the dielectric strength of the i-th part, is the force correction coefficient; The force correction coefficient reflects the influence of force on the insulation performance, and different force correction coefficients are set according to the force range.

9. A method for on-line monitoring of leakage current of high-voltage insulators according to claim 8, characterized in that: In step S4, it is comprehensively analyzed whether to perform leakage monitoring based on the damage amount at the marked position and the marked characteristic value: When the damage amount range at the marked position passes the preset damage amount threshold, it is classified as a high-damage area; otherwise, it is classified as a low-damage area; When the marked characteristic value range passes the preset insulation threshold, it is classified as a high-insulation area; otherwise, it is classified as a low-insulation area; When the damage amount at the marked position is in the low-damage area and the marked characteristic value is in the high-insulation area, no leakage detection is performed; when the damage amount at the marked position is in the high-damage area or the marked characteristic value is in the low-insulation area, leakage detection is performed.

10. An on-line monitoring system for the leakage current of a high-voltage insulator, based on the on-line monitoring method for the leakage current of a high-voltage insulator according to any one of claims 1-8, characterized in that, Including a data acquisition module, a force distribution module, a performance evaluation module, and a leakage detection module; The data acquisition module is used to retrieve the three-dimensional coordinates, dielectric strength, and breakdown current of the voltage insulator collected from the equipment file; collect the signal data of the vibration sensor and the sound sensor; detect and analyze the toughness of each part and transmit it to the subsequent module for the normal operation of the system; The force distribution module comprehensively analyzes the external force bearing range of each part by combining the breakdown current and the toughness of each part; generates a comprehensive force value by analyzing the signal data, obtains the force distribution of the voltage insulator, and transmits the force distribution and the external force bearing range of each part to the performance evaluation module; The performance evaluation module calibrates and matches the marked position based on the force distribution and the three-dimensional coordinates of the voltage insulator, analyzes the damage amount at the marked position in combination with the external force bearing range of each part, and transmits it to the leakage detection module; The leakage detection module combines the dielectric strength to generate a marked characteristic value at the marked position and comprehensively analyzes whether to perform leakage detection based on the damage amount.

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