A porcelain insulator quality assessment system based on multi-physics field coupling analysis

Abstract

The present invention provides a porcelain insulator quality assessment system based on multi-physics field coupling analysis, which relates to the technical field of rod-type post-type porcelain insulator data processing. The present invention adopts an electric-thermal-mechanical multi-physics field joint simulation model to comprehensively reflect the heat accumulation and stress deformation effects caused by electric field concentration. It can accurately capture the electric field concentration coefficient, temperature rise trend coefficient and stress gradient coefficient at sharp points, and form a degradation path prediction under real operating conditions; construct a thread coupling anomaly index Fα of the i-th rod-type post-type porcelain insulator i , which can dynamically evaluate whether the threaded structure has the risk of partial discharge, flashover or breakdown. This technology promotes the simulation of the impact of various pollution, attachments and climate on electric field concentration in reality by introducing equivalent dielectric layer simulation of multiple environmental media; it realizes the quantitative assessment of the risk of corona discharge at sharp points, and promotes the improvement of the reliability of insulator structure design.

Description

Technical Field

[0001] The present invention relates to the technical field of rod-type column porcelain insulator data processing, and in particular to a porcelain insulator quality assessment system based on multi-physical field coupling analysis. Background Art

[0002] Rod-type column porcelain insulators are important supporting and insulating components in power transmission and transformation lines. Their structural design and insulation performance are directly related to the safe and stable operation of the transmission system. The threaded connection, as the key fixing structure between the porcelain insulator and the metal end fitting, not only bears long-term mechanical loads but is also an area where the risk of local electric field distortion is relatively concentrated. In actual operating environments, due to manufacturing errors, aging wear, and external stresses, the threaded area often forms tiny sharp geometric features such as sharp corners, protrusions, and steps. These structural features are prone to cause electric field concentration effects, significantly increasing the local electric field strength, thereby inducing partial discharge, corona discharge, and even insulation breakdown. In severe cases, it can lead to flashover or structural failure of the entire insulator.

[0003] In the prior art, porcelain insulator condition assessments often rely on offline testing or regular on-site infrared temperature measurement and partial discharge testing. However, these methods are mostly based on overall performance evaluations, making it difficult to accurately identify the impact of sharp microstructures within the thread region on insulation performance. Furthermore, traditional analysis methods often ignore the cross-coupling between electric, thermal, and stress fields, making it impossible to predict the potential breakdown risk of insulators from the perspective of the co-evolution of multiple physical fields. In particular, under complex environmental media conditions (such as heat and humidity, high pollution, and high altitude), the corona discharge threshold in the thread region often fluctuates, and sharp points of concentrated electric fields are highly susceptible to becoming sources of pre-discharge in such environments. After partial discharge occurs in the thread region, thermal effects and mechanical stress can further exacerbate local material aging, microcrack propagation, and even structural damage, presenting a typical "electrical-thermal-mechanical" coupled degradation pathway. The information disclosed in the above background section is intended only to enhance understanding of the background of this disclosure and may therefore include information that does not constitute prior art known to persons of ordinary skill in the art. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a porcelain insulator quality assessment system based on multi-physics field coupling analysis to solve the problems mentioned in the background technology.

[0005] The object of the present invention is to provide a porcelain insulator quality assessment system based on multi-physics field coupling analysis to solve the problems raised in the above background technology.

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

[0007] A porcelain insulator quality assessment system based on multi-physics field coupling analysis, including:

[0008] The 3D structural modeling module is used to obtain the structural model information of rod-type column porcelain insulators, establish 3D structural data, and extract the geometric information of the thread end, including pitch, thread depth, and sharp angle characteristic parameters;

[0009] The multi-physics coupling simulation module is used to perform electric field coupling modeling on the threaded area of rod-type column porcelain insulators, build an electric-thermal-mechanical multi-physics field joint analysis model, refine the local mesh of the threaded area to identify several sharp points, and simulate different dielectric environment states to perform electric field simulation to obtain the electric field strength value of the jth sharp point. , and simulate the corona discharge threshold range of the electric field tip distribution to construct the electric field concentration coefficient of the jth sharp point and assessing whether there is a flashover risk at a sharp point; if so, triggering a first warning instruction; if not, generating a first qualified mark;

[0010] At the same time, the temperature rise trend coefficient of the jth sharp point is constructed and stress gradient coefficient ,

[0011] Comprehensive quality prediction module for electric field concentration factor based on the jth sharp point , the temperature rise trend coefficient of the jth sharp point and stress gradient coefficient , construct the thread coupling anomaly index of the i-th rod-type column porcelain insulator , in order to predict whether there is a breakdown risk for rod-type column porcelain insulators due to the combined effects of electric field, temperature rise and stress, and to preset the risk threshold FαY. Greater than or equal to FαY, output local breakdown risk mark; when If it is less than FαY, the second qualified flag is output.

[0012] Furthermore, the three-dimensional structure modeling module includes a structure data input unit and a three-dimensional geometry reconstruction unit;

[0013] The structural data input unit is used to access the three-dimensional laser scanning equipment and CAD design drawings to obtain the geometric structural data of the rod-type column porcelain insulator; the geometric structural data includes the structure of the insulator body, the connection hardware area and the threaded end thereof;

[0014] The 3D geometry reconstruction unit is used to input the collected geometric structure data of rod-type column porcelain insulators into the modeling engine, perform meshing and geometry reconstruction, build a 3D solid model, identify the thread end area in the 3D solid model, and automatically extract thread feature parameters:

[0015] Thread characteristic parameters include:

[0016] Pitch: The axial distance between two adjacent threads in the thread area of the porcelain insulator along the spiral direction;

[0017] Thread depth: The difference between the outside diameter of the thread and the bottom diameter of the thread in the thread area of the porcelain insulator;

[0018] Thread sharpness angle: The tooth angle of each thread cross section in the thread area of the porcelain insulator is used to determine the sharpness.

[0019] Furthermore, the multi-physics field coupling simulation module includes a finite element analysis unit;

[0020] The finite element analysis unit is used to construct and train an electric-thermal-mechanical three-field coupling model based on a COMSOL or ANSYS finite element simulation platform;

[0021] The finite element analysis unit includes an identification unit and an electric field simulation unit:

[0022] The identification unit is used to collect the curvature of the fth normal point and the kth adjacent point in the thread area of the rod-type column porcelain insulator, perform quadratic surface fitting on the fth normal point and the kth adjacent point around it, and obtain a local surface equation. The first principal curvature radius of the surface is and the second principal radius of curvature , respectively representing the maximum and minimum curvature of the surface in two orthogonal directions, and the Gaussian curvature of the fth normal point and the kth adjacent point is calculated by the following formula :

[0023] ;

[0024] Among them, the preset sharp threshold ,when And the thread sharp angle is less than the sharp angle threshold, then it is judged For sharp points; when , then it is judged to be Not a sharp point;

[0025] The electric field simulation unit determines the rod-type column porcelain insulator and the power connection port based on the three-dimensional structural model to perform a first working voltage simulation experiment. Specifically, the first working voltage simulation experiment is as follows: setting an applied voltage of 10 kV, that is, an electric potential of 10,000 V;

[0026] Extracting the coordinates of several sharp points obtained by the recognition unit and establishing a sharp point coordinate set;

[0027] Record the spatial coordinates of the jth sharp point in the three-dimensional structure model, expressed as , use a non-contact electrometer or plasma charge detection equipment to scan the surface of the sharp area point by point, and output the charge density distribution map. After matching the charge density distribution map with the spatial coordinates of the j-th sharp point, the electric field strength value of the j-th sharp point is extracted in sequence. .

[0028] The finite element analysis unit also includes a simulation envelope area unit and a local corona risk prediction unit;

[0029] The simulated envelope region unit is used to simulate different medium environment states to obtain the electric field concentration coefficient of the jth sharp point. ;

[0030] The relative dielectric constants of different media include:

[0031] For dry air, the relative dielectric constant is set to 1.0006;

[0032] In case of humid air, the relative dielectric constant is set to 1.02;

[0033] In case of rain, the relative dielectric constant is set to 78;

[0034] In case of acid rain, the relative dielectric constant is set to 90;

[0035] When dry dust is deposited, the relative dielectric constant is set to 3;

[0036] In the case of wet dust mixed layer, the relative dielectric constant is set to 20;

[0037] When the insulating oil contamination layer is present, the relative dielectric constant is set to 3;

[0038] When the salt spray layer is applied, the relative dielectric constant is set to 40;

[0039] When the plant fibers were deposited, the relative dielectric constant was set to 12;

[0040] For ice and snow layers, the relative dielectric constant is set to 4;

[0041] When contaminating the ice layer, the relative dielectric constant is set to 30;

[0042] In order to simulate the influence of environmental attachments on the electric field distribution, the relative dielectric constants of different media are assigned to the envelope region near the surface of the sharp point, which is equivalent to "covering a layer of dielectric film", and the electric field strength value of the jth sharp point under the medium condition is , simulate the relative dielectric constant of different media, and then calculate the surface charge density of the jth sharp point by the following formula: :

[0043] ;

[0044] Where, Expressed as the relative dielectric constant under the qth medium environment, represents the dielectric constant of vacuum, which is set to 8.854×10 −12 F / m;

[0045] Extract the maximum electric field strength value of the jth sharp point , and extract the ratio of the average electric field value of the entire insulator body area , calculate the maximum electric field strength value of the jth sharp point The ratio of the average electric field in the main body of the insulator to the average electric field in the main body of the insulator The ratio of the electric field concentration coefficient of the jth sharp point is obtained. .

[0046] Furthermore, the local corona risk prediction unit is used to preset the corona discharge threshold , when the electric field concentration coefficient of the jth sharp point Greater than the corona discharge threshold , indicating that the jth sharp point has a corona discharge risk in the qth dielectric environment. If there are fewer than three sharp points in the i-th rod-type column porcelain insulator, the electric field concentration coefficient Exceeding the corona discharge threshold , indicating that there is a flashover risk, triggering the first warning instruction, including:

[0047] Record electric field concentration data and output local corona risk markers;

[0048] If there are three or more sharp points in the i-th rod-type column porcelain insulator, the electric field concentration factor Exceeding the corona discharge threshold , indicating that there is a flashover risk caused by local corona discharge in multiple areas and the risk is more serious than the first warning instruction, then the second warning instruction is triggered, including: marking the product as unqualified;

[0049] If the electric field concentration factor of any sharp point in the i-th rod-type column porcelain insulator is None exceeds the corona discharge threshold , generating a first qualified mark.

[0050] Furthermore, the multi-physics field coupling simulation module also includes a thermal analysis unit and a stress analysis unit;

[0051] The thermal analysis unit is used to use an infrared thermal imager, a thermocouple grid or an optical fiber temperature sensor to obtain a time series temperature map of the sharp point coordinate set during the first working voltage simulation experiment to construct a temperature rise trend coefficient of the jth sharp point within the sampling time period. ;

[0052] The temperature rise trend coefficient of the j-th sharp point The method of obtaining is to extract the temperature value of the jth sharp point from the time series temperature map and calculate the difference between the temperature change range and the corresponding time period.

[0053] Specifically, ;

[0054] Indicates the maximum temperature of the jth sharp point within the sampling period; Indicates the maximum temperature of the jth sharp point within the sampling period; and is the time corresponding to the maximum and minimum temperature;

[0055] Furthermore, the stress analysis unit is used to use a digital image correlation method, a photoelastic test device or an embedded micro stress sensor to generate a time series stress distribution map of the sharp point coordinate set during the first working voltage simulation experiment to construct a stress gradient coefficient of the jth sharp point within the sampling time period. ;

[0056] The stress gradient coefficient of the j-th sharp point The method of obtaining is to extract the stress data of the jth sharp point and its adjacent area from the time series stress spectrum, and calculate the stress gradient coefficient of the jth sharp point by analyzing the ratio of the stress change amplitude of the jth sharp point in the spatial neighborhood to the corresponding distance change , to reflect the degree of local stress concentration at the sharp point.

[0057] Specifically, ;

[0058] represents the stress value of the jth sharp point; represents the stress value of the kth adjacent point adjacent to the jth point; Represents the spatial distance between the jth sharp point and the kth adjacent point;

[0059] If multiple adjacent points (such as 3-5) are used, the stress gradient coefficient of the jth sharp point can be obtained by taking the average value:

[0060] ;

[0061] M represents the total number of adjacent points;

[0062] Furthermore, the comprehensive quality prediction module includes a correlation unit and an anomaly assessment unit;

[0063] The associated unit is used to extract the electric field concentration coefficient of the j-th sharp point , the temperature rise trend coefficient of the jth sharp point And the stress gradient coefficient of the jth sharp point After normalization, the thread coupling anomaly index of the i-th rod-type column porcelain insulator is constructed by weighting , the expression is as follows:

[0064] Where, N represents the total number of sharp points on the i-th rod-type column porcelain insulator;

[0065] w1, w2 and w3 represent the electric field concentration coefficients of the jth sharp point , the temperature rise trend coefficient of the jth sharp point And the stress gradient coefficient of the jth sharp point The weight value is set by the user and the sum of the weights is 1.

[0066] Furthermore, the abnormality evaluation unit is used to preset the risk threshold FαY and calculate the thread coupling abnormality index of the i-th rod-type column porcelain insulator Compare with the risk threshold FαY to obtain quality assessment results, including:

[0067] when If it is greater than or equal to FαY, it means that the rod-type column porcelain insulator has a breakdown risk due to the combined effects of electric field, temperature rise and stress, and a local breakdown risk mark is output;

[0068] when If it is less than FαY, it means that the rod-type column porcelain insulator is in a safe range under the combined effects of electric field, temperature rise and stress, indicating that the structure is stable and adaptable to different media, and the second qualified mark is output;

[0069] After obtaining the first qualified mark and the second qualified mark, it means that the rod-type column porcelain insulator is allowed to leave the factory.

[0070] Compared with the prior art, the present invention has the following beneficial effects:

[0071] The present invention adopts an electric-thermal-mechanical multi-physics field joint simulation model to fully reflect the heat accumulation and stress deformation effects caused by electric field concentration, and can accurately capture the electric field concentration coefficient, temperature rise trend coefficient and stress gradient coefficient at the sharp point, forming a degradation path prediction under the real operating environment. The local feature data of the sharp point is used to construct the thread coupling anomaly index of the i-th rod-type column porcelain insulator. , and set a preset risk threshold FαY, which can dynamically evaluate whether the thread structure has the risk of partial discharge, flashover or breakdown, realize the quantitative and threshold quality assessment process, and avoid the problems of subjective judgment and delayed response of traditional methods.

[0072] In order to simulate the influence of the dielectric layer on the electric field distribution at the sharp point under different natural environments or industrial pollution conditions, the present invention constructs a local envelope layer area near the surface of the sharp point in the thread area, and assigns the relative dielectric constant parameters under the following dielectric environment. The above-mentioned medium is equivalent to "covered with a layer of dielectric film", and simulated to be attached near the sharp point of the thread to achieve a simulated response of the electric field distribution under different working conditions. By introducing equivalent dielectric layer simulations of multiple environmental media, this technology can accurately simulate the influence of various pollution, attachments, and climate on electric field concentration in reality; it can realize the quantitative assessment of the risk of corona discharge at sharp points, promote and improve the reliability of the insulator structure design; and provide a basis for simulation tests to support subsequent corona suppression structure optimization or material coating selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 The present invention is a flowchart of a porcelain insulator quality assessment system based on multi-physics field coupling analysis. DETAILED DESCRIPTION

[0074] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0075] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0076] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0077] Example 1:

[0078] See also Figure 1 The present invention provides a technical solution: a porcelain insulator quality assessment system based on multi-physics field coupling analysis, comprising:

[0079] The 3D structural modeling module is used to obtain the structural model information of rod-type column porcelain insulators, establish 3D structural data, and extract the geometric information of the thread end, including pitch, thread depth, and sharp angle characteristic parameters;

[0080] The multi-physics coupling simulation module is used to perform electric field coupling modeling on the threaded area of rod-type column porcelain insulators, build an electric-thermal-mechanical multi-physics field joint analysis model, refine the local mesh of the threaded area to identify several sharp points, and simulate different dielectric environment states to perform electric field simulation to obtain the electric field strength value of the jth sharp point. , and simulate the corona discharge threshold range of the electric field tip distribution to construct the electric field concentration coefficient of the jth sharp point and assessing whether there is a flashover risk at a sharp point; if so, triggering a first warning instruction; if not, generating a first qualified mark;

[0081] At the same time, the temperature rise trend coefficient of the jth sharp point is constructed and stress gradient coefficient ,

[0082] Comprehensive quality prediction module for electric field concentration factor based on the jth sharp point , the temperature rise trend coefficient of the jth sharp point and stress gradient coefficient , construct the thread coupling anomaly index of the i-th rod-type column porcelain insulator , in order to predict whether there is a breakdown risk for rod-type column porcelain insulators due to the combined effects of electric field, temperature rise and stress, and to preset the risk threshold FαY. Greater than or equal to FαY, output local breakdown risk mark; when If it is less than FαY, the second qualified flag is output.

[0083] In this embodiment, the three-dimensional structural modeling module is used to accurately reconstruct the geometric shape of the threaded end of the rod-type column porcelain insulator, providing a geometric basis for the subsequent analysis of local electric field enhancement, and helping to fully understand the formation location and shape of the sharp point. The system uses an electric-thermal-mechanical multi-physics field joint simulation model to fully reflect the heat accumulation and stress deformation effects caused by electric field concentration. It can accurately capture the electric field concentration coefficient, temperature rise trend coefficient, and stress gradient coefficient at the sharp point, forming a degradation path prediction under a real operating environment. The local feature data of the sharp point is used to construct a thread coupling anomaly index, and a preset risk threshold FαY is set. It can dynamically assess whether the thread structure has the risk of local discharge, flashover, or breakdown, realizing a quantitative and threshold-based quality assessment process, avoiding the problems of subjective judgment and delayed response of traditional methods.

[0084] Example 2

[0085] This embodiment is explained in Example 1, please refer to Figure 1 ,Specifically, the three-dimensional structure modeling module includes a ,structure data input unit and a three-dimensional geometry reconstruction ,unit;

[0086] The structural data input unit is used to access the three-dimensional laser scanning equipment and CAD design drawings to obtain the geometric structural data of the rod-type column porcelain insulator; the geometric structural data includes the structure of the insulator body, the connection hardware area and the threaded end thereof;

[0087] The 3D geometry reconstruction unit is used to input the collected geometric structure data of rod-type column porcelain insulators into the modeling engine, perform meshing and geometry reconstruction, build a 3D solid model, identify the thread end area in the 3D solid model, and automatically extract thread feature parameters:

[0088] Thread characteristic parameters include:

[0089] Pitch: The axial distance between two adjacent threads in the thread area of the porcelain insulator along the spiral direction;

[0090] Thread depth: The difference between the outside diameter of the thread and the bottom diameter of the thread in the thread area of the porcelain insulator;

[0091] Thread sharpness angle: The tooth angle of each thread cross section in the thread area of the porcelain insulator is used to determine the sharpness.

[0092] In this embodiment, by accessing the three-dimensional laser scanning equipment and CAD design drawings through the structural data input unit, the system can obtain the geometric structure data of the rod-type column porcelain insulator, realize high-precision modeling of the insulator body, connecting hardware and threaded ends, and take into account the integration of precise on-site physical modeling and historical design information, thereby enhancing the accuracy and versatility of the modeling.

[0093] Example 3

[0094] This embodiment is explained in Example 1, please refer to Figure 1 ,Specifically, the multi-physics field coupling simulation module includes a finite element analysis unit;

[0095] The finite element analysis unit is used to construct and train an electric-thermal-mechanical three-field coupling model based on the COMSOL or ANSYS finite element simulation platform; the electric-thermal-mechanical multi-physics field coupling model is constructed using the COMSOL or ANSYS finite element simulation platform, which is no longer limited to the analysis of a single electric field distribution, but simultaneously considers thermal effects and mechanical stresses, and comprehensively reflects the evolution process of local degradation of the threaded area under complex operating conditions.

[0096] The finite element analysis unit includes an identification unit and an electric field simulation unit:

[0097] The identification unit is used to collect the curvature of the fth normal point and the kth adjacent point in the thread area of the rod-type column porcelain insulator, perform quadratic surface fitting on the fth normal point and the kth adjacent point around it, and obtain a local surface equation. The first principal curvature radius of the surface is and the second principal radius of curvature , respectively representing the maximum and minimum curvature of the surface in two orthogonal directions, and the Gaussian curvature of the fth normal point and the kth adjacent point is calculated by the following formula :

[0098] ;

[0099] Among them, the preset sharp threshold ,when And the thread sharp angle is less than the sharp angle threshold, then it is judged For sharp points; when , then it is judged to be The recognition unit extracts the principal curvature and Gaussian curvature of each normal point in the threaded area and its adjacent points, enabling mathematical modeling and quantitative identification of sharp structures. Compared to traditional visual recognition or empirical estimation, this method can more objectively identify areas with dangerous features such as sharp corners or protrusions, effectively avoiding misjudgments and missed detections.

[0100] The electric field simulation unit determines the rod-type column porcelain insulator and the power connection port based on the three-dimensional structural model to perform a first working voltage simulation experiment. Specifically, the first working voltage simulation experiment is as follows: setting an applied voltage of 10 kV, that is, an electric potential of 10,000 V;

[0101] Extracting the coordinates of several sharp points obtained by the recognition unit and establishing a sharp point coordinate set;

[0102] Record the spatial coordinates of the jth sharp point in the three-dimensional structure model, expressed as , use a non-contact electrometer or plasma charge detection equipment to scan the surface of the sharp area point by point, and output the charge density distribution map. After matching the charge density distribution map with the spatial coordinates of the j-th sharp point, the electric field strength value of the j-th sharp point is extracted in sequence. .

[0103] By using a non-contact electrometer or plasma charge detection device, the surface of the sharp area is scanned to obtain the charge density distribution map, which is then accurately matched with the coordinate set of the sharp points identified in the three-dimensional structure, thereby extracting the spatial electric field intensity value of each sharp point and improving the spatial resolution and quantitative accuracy of electric field distortion detection.

[0104] The finite element analysis unit also includes a simulation envelope area unit and a local corona risk prediction unit;

[0105] The simulated envelope region unit is used to simulate different medium environment states to obtain the electric field concentration coefficient of the jth sharp point. ;

[0106] The relative dielectric constants of different media include:

[0107] When the air is dry, it means that the relative humidity is less than 30% and it is in a dry state. The relative dielectric constant is set to 1.0006, which is the international standard air value.

[0108] When the air is humid, it means that the relative humidity is higher than 80%, which is a humid state, and the relative dielectric constant is set to 1.02; the polarization ability of water vapor in the air is enhanced under high humidity;

[0109] In case of rain, the relative dielectric constant is set to 78, which is close to the value of pure water;

[0110] In case of acid rain, the relative dielectric constant is set to 90; because it contains ions (H+, SO42-, etc.), the polarization ability is stronger;

[0111] When dry dust is deposited, the relative dielectric constant is set to 3;

[0112] In the case of wet dust mixed layer, the relative dielectric constant is set to 20; there are conductive channels in the wet dust, resulting in a composite effect;

[0113] When the insulating oil contamination layer is present, the relative dielectric constant is set to 3;

[0114] When the salt spray layer is applied, the relative dielectric constant is set to 40;

[0115] When the plant fibers were deposited, the relative dielectric constant was set to 12;

[0116] For ice and snow layers, the relative dielectric constant is set to 4;

[0117] When the ice layer is contaminated, the relative dielectric constant is set to 30; the ice contains salt / dust / ionic pollutants, and the equivalent capacitance increases significantly;

[0118] The relative permittivity is a ratio that represents the dielectric properties of a substance in an electric field relative to the dielectric constant of a vacuum. Essentially, it reflects how the propagation ability of an electric field varies across different media. The dielectric properties (i.e., the response to an electric field) vary with respect to a vacuum. For example, the relative permittivity of water is 78, meaning that water's response to an electric field is 78 times stronger than that of a vacuum.

[0119] This is because water molecules have a strong polarization ability in the electric field and can store more electrical energy. To simulate the influence of environmental attachments on the electric field distribution, the relative dielectric constants of different media are assigned to the envelope region near the sharp point surface, which is equivalent to "covering a layer of dielectric film", and the electric field strength value of the jth sharp point under the medium condition is calculated. , simulate the relative dielectric constant of different media, and then calculate the surface charge density of the jth sharp point by the following formula: :

[0120] ;

[0121] Where, Expressed as the relative dielectric constant under the qth medium environment, represents the dielectric constant of vacuum, which is set to 8.854×10 −12 F / m;

[0122] Extract the maximum electric field strength value of the jth sharp point , and extract the ratio of the average electric field value of the entire insulator body area , calculate the maximum electric field strength value of the jth sharp point The ratio of the average electric field in the main body of the insulator to the average electric field in the main body of the insulator The ratio of the electric field concentration coefficient of the jth sharp point is obtained. .

[0123] In this embodiment, in order to simulate the influence of the dielectric layer on the electric field distribution at the sharp point under different natural environments or industrial pollution conditions, a local envelope layer area is constructed near the surface of the sharp point in the thread area, and the relative dielectric constant parameters under the following dielectric environment are assigned. The above-mentioned medium is equivalent to "covered with a layer of dielectric film" and simulated to be attached near the sharp point of the thread to achieve a realistic response of the electric field distribution under different working conditions. By introducing equivalent dielectric layer simulations of a variety of environmental media, this technology can accurately simulate the effects of various pollution, attachments, and climates on electric field concentration in reality; it can achieve a quantitative assessment of the risk of corona discharge at sharp points, greatly improving the reliability of the insulator structure design; and provide a basis for simulation tests to support subsequent corona suppression structure optimization or material coating selection.

[0124] Example 4

[0125] This embodiment is explained in Example 1, please refer to Figure 1 Specifically, the local corona risk prediction unit is used to preset the corona discharge threshold , when the electric field concentration coefficient of the jth sharp point Greater than the corona discharge threshold , indicating that the jth sharp point has a corona discharge risk in the qth dielectric environment. If there are fewer than three sharp points in the i-th rod-type column porcelain insulator, the electric field concentration coefficient Exceeding the corona discharge threshold , indicating that there is a flashover risk, triggering the first warning instruction, including:

[0126] Record electric field concentration data and output local corona risk markers;

[0127] If there are three or more sharp points in the i-th rod-type column porcelain insulator, the electric field concentration factor Exceeding the corona discharge threshold , indicating that there is a flashover risk caused by local corona discharge in multiple areas and the risk is more serious than the first warning instruction, then the second warning instruction is triggered, including: marking the product as unqualified;

[0128] If the electric field concentration factor of any sharp point in the i-th rod-type column porcelain insulator is None exceeds the corona discharge threshold , generating a first qualified mark.

[0129] In this embodiment, if there are less than 3 sharp points in the i-th rod-type post porcelain insulator, the electric field concentration coefficient exceeds the corona discharge threshold. , it is determined that the insulator has a risk of flashover caused by local corona discharge, and a first warning instruction is triggered, which includes:

[0130] Record the electric field concentration coefficient data of all sharp points of the i-th porcelain insulator;

[0131] Output the coordinates of sharp points where corona discharge risks exist and the electric field concentration value;

[0132] Generate local corona risk markers.

[0133] If there are three or more sharp points in the i-th rod-type column porcelain insulator, the electric field concentration factor exceeds the corona discharge threshold. , it is determined that corona concentrated discharge behavior exists in multiple areas of the insulator, which significantly increases the overall flashover probability and triggers the second warning instruction, which includes:

[0134] Mark the porcelain insulator as a substandard product;

[0135] Output the reasons for non-conformity and the risk coordinate set of the corresponding sharp points.

[0136] This embodiment accurately predicts the local corona discharge and flashover risks of rod-type column porcelain insulators under different dielectric contamination conditions by identifying sharp points, calculating their electric field concentration coefficients, and setting corona discharge thresholds. This improves the intelligence and reliability of insulator quality assessment and provides a basis for their production screening and operation and maintenance.

[0137] Example 5

[0138] This embodiment is explained in Example 1, please refer to Figure 1 ,Specifically, the multi-physics field coupling simulation module also includes a thermal analysis unit and a stress analysis unit;

[0139] The thermal analysis unit is used to use an infrared thermal imager, a thermocouple grid or an optical fiber temperature sensor to obtain a time series temperature map of the sharp point coordinate set during the first working voltage simulation experiment to construct a temperature rise trend coefficient of the jth sharp point within the sampling time period. ;

[0140] The temperature rise trend coefficient of the j-th sharp point The method of obtaining is to extract the temperature value of the jth sharp point from the time series temperature map and calculate the difference between the temperature change range and the corresponding time period.

[0141] Specifically, ;

[0142] Indicates the maximum temperature of the jth sharp point within the sampling period; Indicates the maximum temperature of the jth sharp point within the sampling period; and is the time corresponding to the maximum and minimum temperature;

[0143] In this embodiment, the temperature rise trend coefficient of the jth sharp point is The larger the value, the stronger the electrothermal coupling strength at the sharp point, and the higher the risk of overheating. By constructing a time-series temperature map of the sharp point under applied operating voltage and quantifying its temperature rise trend coefficient, it is helpful to determine whether high energy accumulation exists in the local abnormal area from a thermal field perspective, thereby improving the accuracy of predictions of local corona or thermal breakdown risks.

[0144] Example 6

[0145] This embodiment is explained in Example 1, please refer to Figure 1 Specifically, the stress analysis unit is used to use a digital image correlation method, a photoelastic test device or an embedded micro stress sensor to generate a time series stress distribution map of the sharp point coordinate set during the first working voltage simulation experiment to construct a stress gradient coefficient of the jth sharp point within the sampling time period. ;

[0146] The stress gradient coefficient of the j-th sharp point The method of obtaining is to extract the stress data of the jth sharp point and its adjacent area from the time series stress spectrum, and calculate the stress gradient coefficient of the jth sharp point by analyzing the ratio of the stress change amplitude of the jth sharp point in the spatial neighborhood to the corresponding distance change , to reflect the degree of local stress concentration at the sharp point.

[0147] Specifically, ;

[0148] represents the stress value of the jth sharp point;

[0149] represents the stress value of the kth adjacent point adjacent to the jth point; Represents the spatial distance between the jth sharp point and the kth adjacent point;

[0150] If multiple adjacent points (such as 3-5) are used, the stress gradient coefficient of the jth sharp point can be obtained by taking the average value:

[0151] ;

[0152] M represents the total number of adjacent points;

[0153] In this embodiment, by performing microscale gradient analysis on the stress distribution of sharp points and their surrounding areas, the degree of stress concentration under electro-thermal action can be quantified, providing a basis for identifying physical failure risks such as cracks and breakdown that may be caused by local structural distortion or stress coupling, thereby improving the reliability and foresight of systemic failure prediction.

[0154] Example 7

[0155] This embodiment is explained in Example 1, please refer to Figure 1 ,Specifically, the comprehensive quality prediction module includes an ,associating unit and an anomaly assessment unit;

[0156] The associated unit is used to extract the electric field concentration coefficient of the j-th sharp point , the temperature rise trend coefficient of the jth sharp point And the stress gradient coefficient of the jth sharp point After normalization, the thread coupling anomaly index of the i-th rod-type column porcelain insulator is constructed by weighting , the expression is as follows:

[0157] Where, N represents the total number of sharp points on the i-th rod-type column porcelain insulator;

[0158] w1, w2 and w3 represent the electric field concentration coefficients of the jth sharp point , the temperature rise trend coefficient of the jth sharp point And the stress gradient coefficient of the jth sharp point The weight value is set by the user and the sum of the weights is 1.

[0159] The abnormality evaluation unit is used to preset the risk threshold FαY and calculate the thread coupling abnormality index of the i-th rod-type column porcelain insulator Compare with the risk threshold FαY to obtain quality assessment results, including:

[0160] when If it is greater than or equal to FαY, it means that the rod-type column porcelain insulator has a breakdown risk due to the combined effects of electric field, temperature rise and stress, and a local breakdown risk mark is output;

[0161] when If it is less than FαY, it means that the rod-type column porcelain insulator is in a safe range under the combined effects of electric field, temperature rise and stress, indicating that the structure is stable and adaptable to different media, and the second qualified mark is output;

[0162] After obtaining the first qualified mark and the second qualified mark, it means that the rod-type column porcelain insulator is allowed to leave the factory.

[0163] In this embodiment, the present invention can comprehensively identify potential breakdown risks caused by electric field distortion, thermal stress superposition, and structural micro-damage by introducing a weighted fusion and dynamic evaluation mechanism of multiple physical field indicators; improve the quality screening accuracy and early failure identification capability of rod-type column porcelain insulators, achieve high-reliability factory control of insulators, help reduce the failure rate during operation, and enhance the environmental adaptability and long-term stability of the product.

[0164] The threshold is set to facilitate comparison. The size of the threshold depends on the amount of sample data and the number of bases set by technicians in this field for each set of sample data; as long as it does not affect the proportional relationship between the parameter and the quantized value.

[0165] It should be noted that all calculation formulas in this application document utilize, including but not limited to, regression analysis within machine learning algorithms to deeply analyze the collected parameters and identify their natural trends and interrelationships. Professional software, such as Python's Scikit-learn library or the R language, is used to automatically generate mathematical models that match the data. Model performance is then objectively evaluated through methods such as cross-validation, combined with continuous feedback and optimization to ensure that the created formulas truly reflect the inherent laws of the data, thereby guaranteeing their validity and accuracy, and ensuring that the calculation process complies with the constraints of natural laws rather than being based on artificially set rules.

[0166] The technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods of various embodiments of the present invention.

[0167] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0168] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0169] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A porcelain insulator quality assessment system based on multi-physics field coupling analysis, characterized in that: The following steps are involved: The 3D structural modeling module is used to obtain the structural model information of rod-type column porcelain insulators, establish 3D structural data, and extract the geometric information of the thread end, including pitch, thread depth, and sharp angle characteristic parameters; The multi-physics coupling simulation module is used to perform electric field coupling modeling on the threaded area of rod-type column porcelain insulators, build an electric-thermal-mechanical multi-physics field joint analysis model, refine the local mesh of the threaded area to identify several sharp points, and simulate different dielectric environment states to perform electric field simulation to obtain the electric field strength value of the jth sharp point. , and simulate the corona discharge threshold range of the electric field tip distribution to construct the electric field concentration coefficient of the jth sharp point and assessing whether there is a flashover risk at a sharp point; if so, triggering a first warning instruction; if not, generating a first qualified mark; At the same time, the temperature rise trend coefficient of the jth sharp point is constructed and stress gradient coefficient , Comprehensive quality prediction module for electric field concentration factor based on the jth sharp point , the temperature rise trend coefficient of the jth sharp point and stress gradient coefficient , construct the thread coupling anomaly index of the i-th rod-type column porcelain insulator , in order to predict whether there is a breakdown risk for rod-type column porcelain insulators due to the combined effects of electric field, temperature rise and stress, and to preset the risk threshold FαY. Greater than or equal to FαY, output local breakdown risk mark; when If it is less than FαY, the second qualified flag is output.

2. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 1, characterized in that: The three-dimensional structure modeling module includes a structure data input unit and a three-dimensional geometry reconstruction unit; The structural data input unit is used to access the three-dimensional laser scanning equipment and CAD design drawings to obtain the geometric structural data of the rod-type column porcelain insulator; the geometric structural data includes the structure of the insulator body, the connection hardware area and the threaded end thereof; The three-dimensional geometric reconstruction unit is used to input the collected geometric structure data of the rod-type column porcelain insulator into the modeling engine, perform meshing and geometric reconstruction, establish a three-dimensional solid model, identify the thread end area in the three-dimensional solid model, and automatically extract the thread feature parameters: Thread characteristic parameters include: Pitch: The axial distance between two adjacent threads in the thread area of the porcelain insulator along the spiral direction; Thread depth: The difference between the outer diameter of the thread and the bottom diameter of the thread in the thread area of the porcelain insulator; Thread sharpness angle: The tooth angle of each thread cross section in the thread area of the porcelain insulator is used to determine the sharpness.

3. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 2, characterized in that: The multi-physics field coupling simulation module includes a finite element analysis unit; The finite element analysis unit is used to construct and train an electric-thermal-mechanical three-field coupling model based on a COMSOL or ANSYS finite element simulation platform; The finite element analysis unit includes an identification unit and an electric field simulation unit: The identification unit is used to collect the curvature of the fth normal point and the kth adjacent point in the thread area of the rod-type column porcelain insulator, perform quadratic surface fitting on the fth normal point and the kth adjacent point around it, and obtain a local surface equation. The first principal curvature radius of the surface is and the second principal radius of curvature , respectively representing the maximum and minimum curvature of the surface in two orthogonal directions, and the Gaussian curvature of the fth normal point and the kth adjacent point is calculated by the following formula : ； Among them, the preset sharp threshold ,when And the thread sharp angle is less than the sharp angle threshold, then it is judged For sharp points; when , then it is judged to be Not a sharp point; The electric field simulation unit determines the rod-type column porcelain insulator and the power connection port based on the three-dimensional structural model to perform a first working voltage simulation experiment. Specifically, the first working voltage simulation experiment is as follows: setting an applied voltage of 10 kV, that is, an electric potential of 10,000 V; Extracting the coordinates of several sharp points obtained by the recognition unit and establishing a sharp point coordinate set; Record the spatial coordinates of the jth sharp point in the three-dimensional structure model, expressed as , use a non-contact electrometer or plasma charge detection equipment to scan the surface of the sharp area point by point, and output the charge density distribution map. After matching the charge density distribution map with the spatial coordinates of the j-th sharp point, the electric field strength value of the j-th sharp point is extracted in sequence. .

4. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 3, characterized in that: The finite element analysis unit also includes a simulation envelope area unit and a local corona risk prediction unit; The simulated envelope region unit is used to simulate different medium environment states to obtain the electric field concentration coefficient of the jth sharp point. ; The relative dielectric constants of different media include: For dry air, the relative dielectric constant is set to 1.0006; In humid air, the relative dielectric constant is set to 1.02; In case of rain, the relative dielectric constant is set to 78; In case of acid rain, the relative dielectric constant is set to 90; When dry dust is deposited, the relative dielectric constant is set to 3; In the case of wet dust mixed layer, the relative dielectric constant is set to 20; When the insulating oil contamination layer is present, the relative dielectric constant is set to 3; When the salt spray layer is applied, the relative dielectric constant is set to 40; When the plant fibers were deposited, the relative dielectric constant was set to 12; For ice and snow layers, the relative dielectric constant is set to 4; When contaminating the ice layer, the relative dielectric constant is set to 30; In order to simulate the influence of environmental attachments on the electric field distribution, the relative dielectric constants of different media are assigned to the envelope region near the surface of the sharp point, which is equivalent to "covering a layer of dielectric film", and the electric field strength value of the jth sharp point under the medium condition is calculated. , simulate the relative dielectric constant of different media, and then calculate the surface charge density of the jth sharp point by the following formula: : ； Where, Expressed as the relative dielectric constant under the qth medium environment, represents the dielectric constant of vacuum, which is set to 8.854×10 −12 F / m; Extract the maximum electric field strength value of the jth sharp point , and extract the ratio of the average electric field value of the entire insulator body area , calculate the maximum electric field strength value of the jth sharp point The ratio of the average electric field in the main body of the insulator to the average electric field in the main body of the insulator The ratio of the electric field concentration coefficient of the jth sharp point is obtained. .

5. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 4, characterized in that: The local corona risk prediction unit is used to preset the corona discharge threshold , when the electric field concentration coefficient of the jth sharp point Greater than the corona discharge threshold , indicating that the jth sharp point has a corona discharge risk in the qth dielectric environment. If there are fewer than three sharp points in the i-th rod-type column porcelain insulator, the electric field concentration coefficient Exceeding the corona discharge threshold , indicating that there is a flashover risk, triggering the first warning instruction, including: Record electric field concentration data and output local corona risk markers; If there are three or more sharp points in the i-th rod-type column porcelain insulator, the electric field concentration factor Exceeding the corona discharge threshold , indicating that there is a flashover risk caused by local corona discharge in multiple areas and the risk is more serious than the first warning instruction, then the second warning instruction is triggered, including: marking the product as unqualified; If the electric field concentration factor of any sharp point in the i-th rod-type column porcelain insulator is None exceeds the corona discharge threshold , generating a first qualified mark.

6. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 3, characterized in that: The multi-physics field coupling simulation module also includes a thermal analysis unit and a stress analysis unit; The thermal analysis unit is used to use an infrared thermal imager, a thermocouple grid or an optical fiber temperature sensor to obtain a time series temperature map of the sharp point coordinate set during the first working voltage simulation experiment to construct a temperature rise trend coefficient of the jth sharp point within the sampling time period. ; The temperature rise trend coefficient of the j-th sharp point The method of obtaining is to extract the temperature value of the jth sharp point from the time series temperature map and obtain it by calculating the difference between the temperature change range and the corresponding time period.

7. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 6, characterized in that: The stress analysis unit is used to use a digital image correlation method, a photoelectric testing device or an embedded micro stress sensor to analyze the time series stress distribution map of the sharp point coordinate set during the first working voltage simulation experiment to construct the stress gradient coefficient of the jth sharp point within the sampling time period. ; The stress gradient coefficient of the j-th sharp point The method of obtaining is to extract the stress data of the jth sharp point and its adjacent area from the time series stress spectrum, and calculate the stress gradient coefficient of the jth sharp point by analyzing the ratio of the stress change amplitude of the jth sharp point in the spatial neighborhood to the corresponding distance change , to reflect the degree of local stress concentration at the sharp point.

8. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 7, characterized in that: The comprehensive quality prediction module includes an association unit and an anomaly assessment unit; The associated unit is used to extract the electric field concentration coefficient of the j-th sharp point , the temperature rise trend coefficient of the jth sharp point And the stress gradient coefficient of the jth sharp point After normalization, the thread coupling anomaly index of the i-th rod-type column porcelain insulator is constructed by weighting , the expression is as follows: Where, N represents the total number of sharp points on the i-th rod-type column porcelain insulator; w1, w2 and w3 represent the electric field concentration coefficients of the jth sharp point , the temperature rise trend coefficient of the jth sharp point And the stress gradient coefficient of the jth sharp point The weight value is set by the user and the sum of the weights is 1.

9. The porcelain insulator quality assessment system based on multi-physics field coupling analysis according to claim 8, characterized in that: The abnormality evaluation unit is used to preset the risk threshold FαY and calculate the thread coupling abnormality index of the i-th rod-type column porcelain insulator Compare with the risk threshold FαY to obtain quality assessment results, including: when If it is greater than or equal to FαY, it means that the rod-type column porcelain insulator has a breakdown risk due to the combined effects of electric field, temperature rise and stress, and a local breakdown risk mark is output; when If it is less than FαY, it means that the rod-type column porcelain insulator is in a safe range under the combined effects of electric field, temperature rise and stress, indicating that the structure is stable and adaptable to different media, and the second qualified mark is output; After obtaining the first qualified mark and the second qualified mark, it means that the rod-type column porcelain insulator is allowed to leave the factory.

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