A method and system for predicting the contact temperature rise of a switchgear

Abstract

The present invention provides a method and system for predicting the temperature rise of switch cabinet contacts, including: establishing a contact model identical to the actual working conditions; importing the contact model into simulation software, using the simulation software to perform mesh division on the contact model and converting it into a numerical analysis model; setting reasonable thermal-electrical-mechanical boundary conditions according to the actual operating parameters and working environment of the switch cabinet to complete the setting of electrical parameters; for the numerical analysis model, inputting the contact working voltage, calculating the contact temperature field and electric field, and obtaining the simulation results of the temperature distribution and electric field inside the contact; establishing the correlation between the measured temperature at typical positions on the contact surface and the highest temperature inside the contact, and predicting the peak temperature of the switch cabinet contacts during operation. The present invention is more convenient for monitoring. During the operation of the high-voltage switch cabinet, without directly monitoring the contact temperature, the internal temperature data of the contact can be accurately obtained indirectly by monitoring the external temperature of the contact, and the operation method is simple and safe.

Description

Technical Field

[0001] The present invention belongs to the technical field of simulation, and particularly relates to a method and system for predicting the temperature rise of switch cabinet contacts. Background Technique

[0002] The statements in this part only provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] With the continuous development of the national economy and society, people have put forward higher requirements for the reliability of power supply equipment. As the main electrical equipment in the power system, high-voltage switch cabinets mainly play the role of receiving and distributing electric energy, and their quality and reliability are directly related to the safe and stable operation of the main transformer and even the substation. Operating experience shows that the phenomenon of internal heating or even overheating in 10kV - 35kV switch cabinets is widespread, especially in the main incoming cabinets or during the peak seasonal electricity consumption period. The temperature rise of switch cabinet contacts causing faults is one of the most common forms of internal overheating faults in switch cabinets. The petal contacts of switch cabinets are elastic contact fingers or externally added spring structures, and the surfaces of the contact fingers and static contacts are silver-plated. However, due to the differences in the performance and quality of elastic materials, and the long-term action under the "thermal-mechanical-electric" multi-physical field, creep fatigue, performance degradation or even fracture of the contact finger or spring materials often occur, making it difficult to ensure the contact tightness; after several operations of the silver-plated layer, surface wear and oxidation are inevitable, and the phenomenon of increased contact resistance is widespread.

[0004] In order to ensure the safety and reliability of switch cabinet operation and avoid overheating faults, various means of contact temperature monitoring have been proposed, such as temperature indicating wax tablets, infrared temperature measurement, optical fiber temperature measurement, etc. However, due to the complex structure of the contacts and the harsh service conditions, the above means can generally only measure the external temperature of the contacts, and it is difficult to measure the internal temperature of the contacts (especially the contact area between the contact fingers and the moving / static contacts), determine the high-temperature area of heat generation, and carry out accurate fault diagnosis. Usually, the contact area between the contact fingers and the moving / static contacts is a separable contact area, and it is difficult to ensure the contact tightness. Coupled with problems such as wear and aging of the contact plating, the contact resistance of the contact area between the contact fingers and the moving / static contacts increases, becoming the origin location and high-temperature area of the heating fault. Accurately predicting the temperature rise of the contacts and determining the high-temperature area are important factors for ensuring the safety of switch cabinet operation and also important bases for switch cabinet fault diagnosis.

[0005] To solve the above problems such as the difficulty in measuring the internal temperature of the contacts during the operation of the switchgear and the difficulty in determining the high-temperature area, a detection method for cable contact faults in high-voltage switchgear based on a multiple linear regression model has been disclosed in the research. By analyzing the characteristics of the contact temperature data of the high-voltage switchgear, a multiple linear regression model with undetermined coefficients is given. After preprocessing the contact temperature data, the contact temperature data of the A, B, and C phases of the high-voltage switch are written into the multiple linear regression model in a certain format, and then a feature engineering is established. Three interval sequences of 20 minutes, 40 minutes, and 1 hour are selected, and five attributes of the lowest value, the highest value, the average value, and the mean number of times in the interval are selected as the feature attributes within the interval. This method considers the influence of multiple factors on the temperature, designs an optimized multiple linear regression model, makes the predicted value closer to the true value, is suitable for long-term temperature prediction, and is convenient for fault maintenance of high-voltage switchgear.

[0006] However, the inventor's research found that: during the operation of the switchgear, this method cannot directly measure the contact temperatures of the A, B, and C phases of the high-voltage switch. There is still a large gap between the measured values of the three-phase contact temperatures and the actual internal temperatures of the contacts, and accurate measurement cannot be achieved. Moreover, the temperature rise of the contacts of the high-voltage switchgear is often related to multiple physical field factors. Using a simple linear regression model for prediction has a large gap with the actual situation of the temperature rise of the contacts of the high-voltage switchgear, and it is difficult to accurately predict the temperature rise of the switchgear contacts and determine the high-temperature area of the switchgear.

[0007] In addition, a switchgear electric field prediction and optimization method based on support vector machines and genetic algorithms has been disclosed in the research, including selecting the main factors and levels affecting the internal electric field distribution of the switchgear, establishing an orthogonal test table, performing internal electric field calculations of the switchgear, obtaining the maximum electric field intensity on the surface of the contact box, constructing training samples, using a support vector machine regression model to establish a prediction model for the maximum electric field intensity on the surface of the switchgear contact box, selecting influence factor and level combinations for finite element electric field calculations, obtaining the maximum electric field intensity on the surface of the contact box, constructing verification samples, optimizing the penalty factor and kernel function parameters of the prediction model, and obtaining the optimized prediction model. Using genetic algorithms to optimize the design of the switchgear structure, the influence factor values corresponding to the minimum value of the maximum electric field intensity on the surface of the contact box are the optimized structural parameters. This method can simply, efficiently, and accurately predict the switchgear electric field and optimize the structure.

[0008] However, the inventor's research found that although this method accurately established a prediction model for the maximum electric field intensity on the surface of the switchgear contact box and selected influence factor and level combinations for finite element electric field calculations, the applicable scenario of this model has great limitations. When modeling and calculating the electric field in contact with the high-voltage switchgear contacts, due to involving multiple contacts, the model is complex and there are many influence factor values, making it difficult to simply implement through this model.

[0009] In addition to continuously measuring the temperature rise of the contacts of high-voltage switchgear itself and researching model prediction, researchers have also explored temperature sensors for switchgear contacts.

[0010] For example: A research has disclosed a wireless temperature measurement device for switchgear, which includes a high-voltage side transmitting system, a low-voltage side receiving system, and a base station. The high-voltage side transmitting system is communicatively connected to the low-voltage side receiving system, and the low-voltage side receiving system is communicatively connected to the base station.

[0011] This wireless temperature measurement device for switchgear adopts a temperature measurement and wireless transmission scheme using a semiconductor IC temperature sensor. This temperature measurement device consists of three parts: a high-voltage side transmitting system, a low-voltage side receiving system, and a base station. The high-voltage side transmitting system mainly completes the measurement of the temperature of the contacts of the high-voltage switchgear and the wireless transmission of temperature data. The low-voltage side receiving system mainly completes the reception of wireless temperature data and uploads the temperature data to the base station for monitoring in the form of the MODBUS communication protocol through the RS-232 bus.

[0012] However, the inventors have found through research that although this device can accurately measure the temperature rise of the switchgear, in the actual operation process, the installation of the semiconductor IC temperature sensor is relatively cumbersome and has high requirements for the working environment. Summary of the Invention

[0013] To overcome the deficiencies of the above-mentioned prior art, the present invention provides a method for predicting the temperature rise of switchgear contacts, which can indirectly and accurately obtain the internal temperature data of the contacts by monitoring the external temperature of the contacts, and the operation method is simple and safe.

[0014] To achieve the above object, one or more embodiments of the present invention provide the following technical solutions:

[0015] In a first aspect, a method for predicting the temperature rise of switchgear contacts is disclosed, including:

[0016] According to the shape characteristics and related dimensional parameters of the high-voltage contacts of the switchgear, a contact model identical to the actual working conditions is established;

[0017] The contact model is imported into simulation software, and the simulation software is used to perform mesh division on the contact model and convert it into a numerical analysis model;

[0018] According to the actual operating parameters and working environment of the switchgear, reasonable thermal-electric-force boundary conditions are set to complete the setting of electrical parameters;

[0019] For the numerical analysis model, the working voltage of the contacts is input, and the temperature field and electric field of the contacts are calculated to obtain the simulation results of the internal temperature distribution and electric field of the contacts;

[0020] Establish the correlation between the measured temperature at typical positions on the contact surface and the highest temperature inside the contact to predict the peak temperature of the high-voltage switchgear contacts during operation.

[0021] A further technical solution further includes: a verification step: measuring the temperature characteristic values at typical positions on the contact surface, comparing and analyzing the measured values with the simulation results to verify the simulation results, and thus analyzing the actual situation of the temperature field and electric field inside the switchgear contacts.

[0022] A further technical solution: The predicted peak temperature of the high-voltage switchgear contacts during operation is used to evaluate the operating safety of the switchgear.

[0023] A further technical solution: For the numerical analysis model, when inputting the operating voltage of the contact, the operating voltage and operating current are controllable. By making the contact at different operating voltages, the temperature field and electric field of the contact under different operating voltages are obtained.

[0024] A further technical solution further includes setting the thermophysical properties and thermoelectric properties of the material. The thermophysical properties and thermoelectric properties are obtained by defining the thermal conductivity and resistivity of the material of the switchgear trolley contact.

[0025] A further technical solution: After setting reasonable thermal-electric-force boundary conditions, apply a set current to one end of the energized conductor and a set voltage to the other end to complete the setting of electrical parameters.

[0026] A further technical solution: After obtaining the simulation results of the temperature distribution and electric field inside the contact, obtain the temperature of the contact area between the contact finger and the moving / static contact, and then determine the high-temperature area where heat is generated for fault diagnosis.

[0027] In a second aspect, a system for predicting the temperature rise of switchgear contacts is disclosed, including:

[0028] A contact model establishment module, used to establish a contact model identical to the actual working conditions according to the shape characteristics and relevant dimensional parameters of the high-voltage contacts of the switchgear;

[0029] A numerical analysis model establishment module, used to import the contact model into simulation software, and use the simulation software to perform mesh division on the contact model and convert it into a numerical analysis model;

[0030] A boundary condition setting module, used to set reasonable thermal-electric-force boundary conditions according to the actual operating parameters and working environment of the switchgear;

[0031] A simulation module, used to input the operating voltage of the contact for the numerical analysis model, calculate the temperature field and electric field of the contact, and obtain the simulation results of the temperature distribution and electric field inside the contact;

[0032] A prediction module, which is used to establish the correlation between the measured temperature at typical positions on the contact surface and the highest temperature inside the contact, and predict the peak temperature of the high-voltage switchgear contacts during operation.

[0033] The above one or more technical solutions have the following beneficial effects:

[0034] The monitoring of the present invention is more convenient. During the operation of the high-voltage switchgear, without directly monitoring the contact temperature, the internal temperature data of the contact can be indirectly and accurately obtained by monitoring the external temperature of the contact, and the operation method is simple and safe.

[0035] The present invention has high accuracy in temperature rise prediction and high-temperature area determination. Based on the finite element numerical simulation method, here it can be a commercial finite element method, such as ANSYS or ABAQUS can be used to achieve. Considering the actual working conditions of the high-voltage switchgear contacts comprehensively, set realistic boundary conditions, and perform parallel coupling analysis on the simulation results and the temperature measurement results on the contact surface. For example, the temperature measurement result at a typical position on the contact arm surface is 30 degrees, and the predicted peak temperature is 80 degrees; while the measurement result is 40 degrees, and the corresponding predicted temperature is 83 degrees; calibrate and organize all the results into a data table or a corresponding curve, so as to obtain the relationship between the external typical position temperature and the internal peak temperature.

[0036] The present invention accurately predicts the temperature rise situation in the contact area and inside according to the established relationship between the temperature rise on the contact surface and the temperature rise inside the contact, and accurately determines the high-temperature area.

[0037] The cost of the present invention is relatively lower than the traditional method. Compared with the traditional temperature measurement method, the present invention has low requirements for the working conditions of the temperature measurement sensor, and the temperature sensor does not need to directly contact the high-temperature area. Therefore, ordinary thermocouples can be used to collect temperature data, saving costs.

[0038] The operation method of the present invention is simple, low in cost, has universality, and is easy to scale up production.

[0039] The advantages of the additional aspects of the present invention will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0041] Figure 1 It is a flowchart for predicting the temperature rise and fault diagnosis of the switchgear based on thermoelectric modeling.

[0042] Figure 2It is a geometric model of the switch cabinet contact, including the rear busbar 1 of the contact box, the static contact 2, the finger of the petal contact 3, and the moving contact arm 4.

[0043] Figure 3 It is a grid model of the switch cabinet contact.

[0044] Figure 4 It is the boundary condition of the switch cabinet contact model.

[0045] Figure 5 It is the internal temperature field of the switch cabinet contact. Specific implementation manners

[0046] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0047] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present invention.

[0048] Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0049] Embodiment 1

[0050] As described above, there is currently a problem that it is difficult to measure the high temperature at the contact part between the petal and the contact arm in the temperature monitoring of the switch cabinet contact. For this reason, this embodiment discloses a method for predicting the temperature rise of the switch cabinet contact. Through simulation diagrams, the grid and node numbers of the contact points between the petals can be directly obtained. By applying the node numbers, the corresponding temperature data can be extracted through post-processing.

[0051] The present invention establishes a corresponding numerical model according to the actual working conditions and calibrates it, which is equivalent to realizing the prediction of the internal temperature of the switch cabinet contact through digital twin. In addition, the present invention establishes a corresponding calibration relationship between the result predicted by the model and the temperature at the typical position outside the contact arm (located in the high-temperature area where it does not contact the petal), and establishes a corresponding number table, so as to realize measuring the low-temperature area outside the contact arm, obtaining the high-temperature area where the contact arm contacts the petal, and realizing the prediction of the peak temperature and temperature rise.

[0052] See Figure 1 , the specific steps for the present invention to realize the method for predicting the temperature rise of the switch cabinet contact are as follows:

[0053] Step 1, establish an accurate CAD model of the contact according to the specific shape characteristics and relevant dimensional parameters of the high-voltage contact;

[0054] Step 2, according to the actual analysis needs, import the CAD model of the contact into computer simulation software, perform reasonable mesh division, and convert it into a CAE model;

[0055] Step 3: Set reasonable thermal-electric-force boundary conditions according to the actual operating parameters and working environment of the high-voltage switchgear;

[0056] Here, it is necessary to set according to the actual operating parameters, such as the magnitude of current, the magnitude of voltage, the ambient temperature, etc.

[0057] Step 4: Based on the finite element numerical analysis method, input the working voltage, calculate the contact temperature field and electric field, and obtain the simulation results of the temperature distribution and electric field inside the contact;

[0058] Step 5: Measure the temperature characteristic values at three typical positions A, B, and C on the contact surface, compare the measured values with the simulated values for analysis, verify the accuracy of the simulation calculation results, and systematically analyze the actual situation of the temperature field and electric field inside the switchgear contact;

[0059] Step 6: Establish the correlation between the measured temperature at the typical position on the contact surface and the highest temperature inside the contact, accurately predict the peak temperature of the high-voltage switchgear contact during operation, and evaluate the safety of the switchgear operation.

[0060] Here, the peak temperature has a corresponding relationship with the temperature at the measurement point, but does not satisfy a simple linear or curve relationship, and is related to the specific service conditions.

[0061] The present invention realizes the measurement of the highest temperature at the contact point between the contact petal and the contact arm through the thermoelectric coupling model and the measured temperature at the typical position outside the contact arm and exposed outside the contact petal contact area, can effectively predict the highest temperature during the operation of the switchgear, and is beneficial to improving the operation safety of the switchgear.

[0062] The following combines specific embodiments to further elaborate on the present invention. It should be noted that the specific embodiments are interpretations rather than limitations of the present invention.

[0063] As described above, the phenomenon of internal heating or even overheating in 10kV - 35kV switchgears is widespread, especially in the main incoming cabinets or during the peak seasonal electricity consumption period. Due to the complex structure of the contact and the harsh service conditions, traditional methods can generally only measure the external temperature of the contact, and it is difficult to measure the temperature inside the contact (especially in the contact area between the contact fingers and the moving / static contacts), determine the high-temperature area of heat generation, and carry out accurate fault diagnosis. To solve the above problems such as the difficulty in measuring the temperature inside the contact and the difficulty in determining the high-temperature area during the operation of the switchgear, the present invention proposes a thermal-electric coupling temperature rise simulation model for the high-voltage switchgear contact based on finite elements, and accurately predicts through coupled analysis with the temperature measurement results at the typical positions of the switchgear contact.

[0064] In some instances, the materials of the contacts can be different materials, such as silver-plated copper and gold-plated copper. The current passing through the switchgear contacts can vary, such as 1000A and 1250A, the voltage applied to the switchgear contacts can vary, such as 12kV and 10kV, the sizes of the switchgear contacts can be different, and the shapes, sizes of the switchgear contact springs and the pre-tightening forces generated by the springs can be different.

[0065] Reference Figure 2 , an example of a simulated assembly drawing of a method for predicting the temperature rise, determining the high-temperature area and diagnosing faults of switchgear contacts based on finite element includes: the rear busbar 1 of the contact box, the static contact 2, the finger of the petal contact 3, and the moving contact arm 4.

[0066] The simulated contact material is T2 copper alloy with silver plating on the surface. The overall size of the petal contact piece is 60mm in diameter, 20mm at the widest part, and 3mm thick. The size of the static contact is 49mm in diameter and 82mm long. The size of the primary contact arm is 50mm in diameter and 155mm long. In this model, the spring is simplified, and the action of the spring pre-tightening force is reflected through the contact areas between the petal contact and the moving contact arm and the static contact arm. The actual simulation method includes the following steps:

[0067] According to the shape characteristics and relevant dimensional parameters of the high-voltage contacts, an accurate contact CAD model is established, and according to the positions of the switchgear contacts in the actual working process, each contact component is reasonably assembled to make it the same as the actual working conditions.

[0068] According to the actual analysis needs, the assembled CAD model is imported into computer simulation software for reasonable mesh generation and converted into a CAE model. During the finite element simulation process, selecting an appropriate mesh division can not only improve the calculation accuracy but also make the simulation calculation time appropriate, while an inappropriate mesh division will cause relatively large errors in the calculation results, and even cause the calculation process not to converge and unable to obtain the required simulation results; and if the mesh division is too fine, it will greatly increase the simulation calculation time and put higher requirements on the performance of the computer. Therefore, local mesh refinement is carried out on the complex part of the petal contact, among which, the total number of meshes is 73350, and the total number of nodes is 131980. As Figure 3 shown in the model mesh.

[0069] Set the thermal and thermoelectric properties of the material, and use ANSYS Workbench software to define the thermal conductivity and resistivity of the switchgear trolley contact material. The material in the model is copper in the ANSYS workbench material library, with a thermal conductivity of 401W / m·℃, and the resistivity changes linearly with time.

[0070] Set reasonable thermal - electric - force boundary conditions according to the actual operating parameters and working environment of the high - voltage switchgear. Apply a current of 1250 A at one end of the energized conductor and a voltage of 12 kV at the other end to complete the setting of electrical parameters. For the thermal simulation parameters of the energized conductor, considering the heat convection and radiation between the conductor and the surrounding environment, the surface convective heat transfer coefficient is taken as 5 W / (m²·°C), and the radiation coefficient is 0.78. The initial temperature and the ambient temperature are both 22 °C. The boundary conditions set for the conductor loop are as Figure 4 shown.

[0071] Based on the finite - element numerical analysis method, input the working voltage, calculate the temperature field and electric field of the contact, and obtain the simulation results of the temperature distribution and electric field inside the contact. The current density distribution of the contact fingers. In the calculation results, the current density shows an obvious contraction at the end of the contact fingers, and the maximum current density reaches 3.5264×10 6 A / m², which is much larger than 1117.4 A / m² at the edge of the contact piece. Under the steady - state condition of 1250 A, the temperature distribution of the conductor is as Figure 5 shown. The lowest temperature appears at the rear busbar of the contact box, which is 65.99 °C. The temperature of the petal - type contact and the area near it with contact resistance is relatively high because of the electrical contact heating near the contact part, and the electrical contact is an important heat source. For the temperature distribution of the petal - type contact, the highest temperature is 94.434 °C, which appears at the position where the contact finger contacts the moving contact arm, and the lowest temperature is 93.181 °C, which appears on the contact piece body. Generally speaking, due to the good thermal conductivity of copper, the temperature difference on the petal - type contact is not large. It can be seen from the results that the temperature at the end of the contact finger on the static contact side is slightly lower than that at the end of the contact finger on the moving contact arm side, and the temperature of the contact fingers on both sides of the petal - type contact is slightly higher than that of the contact piece body, mainly because the equivalent cross - section of the current flow at the contact finger on the moving contact arm side is slightly smaller than that on the static contact side.

[0072] Measure the temperature characteristic values at three typical positions A, B, and C on the surface of the contact, compare the measured values with the simulated values for analysis, verify the simulation calculation results, and systematically analyze the actual situation of the temperature field and electric field inside the switchgear contact.

[0073] Establish the correlation between the measured temperature at the typical positions on the contact surface and the highest temperature inside the contact, accurately predict the peak temperature of the high - voltage switchgear contact during operation, and evaluate the safety of the switchgear operation.

[0074] Example Two

[0075] The purpose of this example is to provide a computing device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the above - mentioned method are implemented.

[0076] Example Three

[0077] The purpose of this embodiment is to provide a computer-readable storage medium.

[0078] A computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, it executes the steps of the above method.

[0079] Embodiment 4

[0080] The purpose of this embodiment is to provide a temperature rise prediction system for switch cabinet contacts, including:

[0081] A contact model establishment module, configured to establish a contact model identical to the actual working condition according to the shape characteristics and related dimensional parameters of the high-voltage contacts of the switch cabinet;

[0082] A numerical analysis model establishment module, configured to import the contact model into simulation software, perform mesh division on the contact model by using the simulation software, and convert it into a numerical analysis model;

[0083] A boundary condition setting module, configured to set reasonable thermal-electric-force boundary conditions according to the actual operating parameters and working environment of the switch cabinet;

[0084] A simulation module, configured to input the contact working voltage for the numerical analysis model, calculate the contact temperature field and electric field, and obtain the simulation results of the temperature distribution and electric field inside the contact;

[0085] A prediction module, configured to establish the correlation between the measured temperature at typical positions on the contact surface and the highest temperature inside the contact, and predict the peak temperature of the high-voltage switch cabinet contacts during operation.

[0086] Through the above solution, the present invention is more convenient for monitoring. During the operation of the high-voltage switch cabinet, without directly monitoring the contact temperature, the internal temperature data of the contact can be indirectly and accurately obtained by monitoring the external temperature of the contact, and the operation method is simple and safe.

[0087] The present invention establishes a thermoelectric coupling multi-physical field model for switch cabinet contacts, and combines the measured temperature at the contact arm to obtain the internal temperature field of the contact, thereby determining the highest temperature at the contact. The accuracy of temperature rise prediction and high-temperature area determination is high. Based on the finite element numerical simulation method, considering the actual working conditions of the high-voltage switch cabinet contacts, setting boundary conditions that conform to the actual situation, performing parallel coupling analysis on the simulation results and the temperature measurement results on the contact surface, and accurately predicting the temperature rise situation in the contact area and inside the contact according to the established relationship between the temperature rise on the contact surface and the temperature rise inside the contact, and accurately determining the high-temperature area.

[0088] The present invention is relatively lower than the traditional method. Compared with the traditional temperature measurement method, the present invention has lower requirements for the working conditions of the temperature measurement sensor. The temperature sensor does not need to directly contact the high-temperature area. Therefore, ordinary thermocouples can be used to collect temperature data, saving costs.

[0089] In the devices of the second, third, and fourth embodiments above, the steps involved correspond to those of the first method embodiment. For specific implementation details, reference may be made to the relevant description part of the first embodiment. The term "computer-readable storage medium" should be understood to include a single medium or multiple media containing one or more sets of instructions; it should also be understood to include any medium that can store, encode, or carry a set of instructions for execution by a processor and cause the processor to execute any method in the present invention.

[0090] Those skilled in the art should understand that the above-mentioned modules or steps of the present invention can be implemented by a general-purpose computer device. Optionally, they can be implemented by program codes executable by a computing device, so that they can be stored in a storage device for execution by the computing device, or they can be separately fabricated into individual integrated circuit modules, or multiple modules or steps among them can be fabricated into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0091] Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that, based on the technical solutions of the present invention, various modifications or deformations that can be made without creative efforts by those skilled in the art are still within the protection scope of the present invention.

Claims

1. A method for predicting the temperature rise of switch cabinet contacts, characterized in that, Including: According to the shape characteristics and relevant dimensional parameters of the high-voltage contact of the switch cabinet, a contact model identical to the actual working conditions is established; The contact model is imported into the simulation software, and the simulation software is used to perform mesh generation on the contact model and convert it into a numerical analysis model; Local mesh refinement is performed on the complex part of the petal contact; According to the actual operating parameters and working environment of the switch cabinet, thermal-electrical-mechanical boundary conditions are set to complete the setting of electrical parameters; For the numerical analysis model, the contact working voltage is input, the contact temperature field and electric field are calculated, and the simulation results of the temperature distribution and electric field inside the contact are obtained; Verification step: Measure the temperature characteristic values at typical positions on the contact surface, compare the measured values with the simulation results for analysis to verify the simulation results, and thus analyze the actual situation of the temperature field and electric field inside the switch cabinet contact; Establish the correlation between the measured temperature at typical positions on the contact surface and the highest temperature inside the contact, and predict the peak temperature of the high-voltage switch cabinet contact during operation; After obtaining the simulation results of the temperature distribution and electric field inside the contact, obtain the temperature of the contact area between the finger and the moving / static contact, and then determine the high-temperature area where heat is generated for fault diagnosis.

2. The method for predicting the contact temperature rise of a switchgear cabinet according to claim 1, wherein The predicted peak temperature of the high-voltage switch cabinet contact during operation is used to evaluate the operating safety of the switch cabinet.

3. The method for predicting the contact temperature rise of a switchgear cabinet according to claim 1, wherein For the numerical analysis model, when the contact working voltage is input, the working voltage and working current are controllable. By making the contact at different working voltages, the contact temperature field and electric field under different working voltages are obtained.

4. The method for predicting the contact temperature rise of a switchgear cabinet according to claim 1, characterized in that, It also includes setting the thermal physical properties and thermoelectric properties of the material. The thermal physical properties and thermoelectric properties are obtained by defining the thermal conductivity and resistivity of the switch cabinet trolley contact material.

5. The method for predicting the contact temperature rise of a switchgear cabinet according to claim 1, characterized in that, After setting reasonable thermal-electrical-mechanical boundary conditions, a set current is applied to one end of the energized conductor and a set voltage is applied to the other end to complete the setting of electrical parameters.

6. A switchgear contact temperature rise prediction system, which implements a switchgear contact temperature rise prediction method as described in any one of claims 1-5, characterized in that, Including: A contact model establishment module for establishing a contact model identical to the actual working conditions according to the shape characteristics and relevant dimensional parameters of the high-voltage contact of the switch cabinet; A numerical analysis model establishment module for importing the contact model into the simulation software and using the simulation software to perform mesh generation on the contact model and convert it into a numerical analysis model; A boundary condition setting module for setting reasonable thermal-electrical-mechanical boundary conditions according to the actual operating parameters and working environment of the switch cabinet; A simulation module for inputting the contact working voltage for the numerical analysis model, calculating the contact temperature field and electric field, and obtaining the simulation results of the temperature distribution and electric field inside the contact; A prediction module for establishing the correlation between the measured temperature at typical positions on the contact surface and the highest temperature inside the contact, and predicting the peak temperature of the high-voltage switch cabinet contact during operation.

7. A computing device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the method described in any one of claims 1-5 above.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it executes the steps of the method described in any one of claims 1-5 above.

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