A closing resistor local damage principle simulation modeling method and system and a storage medium

Abstract

This invention relates to a simulation modeling method, system, and storage medium for the local failure principle of a closing resistor. The method includes: generating a random curve of the closing resistor end face based on the microscopic modeling parameters of the closing resistor end face using a random curve generation formula, and establishing a microscopic morphology model of the end face; establishing a simulation numerical model of the local failure principle of the closing resistor based on the electrical parameters of the closing resistor and the microscopic morphology model of the end face; sequentially setting the impact current waveform of the simulation numerical model according to preset experimental requirements, and conducting impact simulation experiments; acquiring the temperature distribution and internal current distribution data of the simulation numerical model during the simulation process, calculating the limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor, optimizing the simulation numerical model, and completing the modeling. Compared with the prior art, this invention can not only accurately establish a numerical simulation model of the local failure principle of the closing resistor, but also evaluate the impact of the flatness of the closing resistor end face on the performance of the closing resistor, ensuring the stable operation of the power system.

Description

Technical Field

[0001] This invention relates to the field of tank-type circuit breaker technology, and in particular to a simulation modeling method, system and storage medium for the principle of local damage to closing resistor. Background Technology

[0002] Tank-type circuit breakers are one of the core pieces of equipment in ultra-high voltage substations. To suppress inrush currents generated during opening and closing operations, a closing resistor is typically installed. However, during long-term operation, this resistor not only bears enormous mechanical stress but also must withstand the repeated impact of closing surge currents. Faults caused by this can range from minor issues like contact arcing, loosening or jamming of components to more serious problems such as fire or even explosion. Prolonged opening and closing surges can damage the surface of the closing resistor, even causing resistor debris to flake off. If this debris forms an abnormal current path inside the circuit breaker, it can easily trigger flashover, causing operational interruptions and seriously threatening the reliability of the power grid.

[0003] Typical faults of the closing resistor can be summarized into two categories: (1) Mechanical stress damage: The strong mechanical stress generated during the opening and closing process can induce microcracks on the surface of the resistor. These cracks not only degrade the electrical performance of the resistor, but also significantly weaken its local compressive strength, resulting in a decrease in its current withstand capability.

[0004] (2) Thermal shock and debris hazards: Injection of impact current into the closing resistor (which is essentially a nonlinear resistive material) will cause a temperature rise, resulting in the shedding of surface debris and its deposition at the bottom of the tank. These debris may overlap between the resistor and other components, forming a conductive path and ultimately triggering a flashover accident.

[0005] Such hazards occur frequently in power systems. Therefore, domestic and foreign research institutions continue to focus on improving the closing resistor of tank-type circuit breakers, with the main directions including: 1. Optimizing the opening and closing operation strategy to reduce the impact of inrush current; 2. Investigating the composition of resistor materials and optimizing the formula to improve performance; 3. Improving the connection structure and method of circuit breakers to enhance the reliability of resistor operation.

[0006] Currently, existing technologies for quality inspection and performance evaluation of closing resistors mainly employ simulation modeling methods. For example, Chinese patent CN118884197B discloses a modeling method for quality inspection of closing resistors based on the principle of equivalent failure. This method establishes a closing resistor model based on its electrical parameters and geometric model, sets material parameters such as conductivity, coefficient of thermal expansion, Young's modulus, density, and specific heat capacity, and establishes an equivalent failure simulation numerical model of the closing resistor. Simulation calculations are performed using injected impulse current waveforms to evaluate the impulse current limit that the closing resistor can withstand. Chinese patent application CN119129017A discloses a model establishment method for quality inspection of closing resistors. This method also establishes a simulation numerical model based on the electrical parameters and geometric model of the closing resistor, and performs simulation analysis by setting impulse current waveforms, temperature characteristics, and stress characteristics.

[0007] However, the existing technologies mentioned above suffer from insufficient modeling in the study of the failure mechanism of the closing resistor. Current modeling methods typically treat the closing resistor's end face as an ideal plane, failing to consider the impact of end face flatness and micro-roughness on electrical contact performance, leading to discrepancies between simulation results and actual conditions. In practical applications, the closing resistor's end face exhibits micro-undulations and roughness characteristics. These micro-geometric features significantly affect the current and temperature distribution in the electrical contact area, thereby influencing the local failure mode of the closing resistor. Existing technologies lack modeling and analysis of the end face's micro-morphology, making it impossible to accurately assess the impact of end face flatness on the closing resistor's performance.

[0008] Furthermore, existing technologies, when analyzing the failure mechanism of closing resistors, primarily focus on overall temperature and stress changes, lacking in-depth analysis of the local failure process in the electrical contact area. Failure of the closing resistor often originates from localized overheating at the electrical contact point, where local stress exceeds the material's limits, leading to crack initiation and propagation, ultimately resulting in overall failure. Current technologies fail to focus on the local temperature and stress distribution in the electrical contact area, making it impossible to accurately determine the cause and critical location of closing resistor failure, and also lacking methods for quantitatively assessing the local failure stress limit value of the closing resistor.

[0009] Therefore, a new technical solution is needed to establish a simulation model of the local failure principle of the closing resistor that takes into account the micro-morphological characteristics of the end face, accurately evaluate the impact of the end face flatness on the performance of the closing resistor, analyze the local temperature and stress distribution in the electrical contact area, calculate the limit value of the impact current and the limit value of the local failure stress that the closing resistor can withstand, and provide a more accurate theoretical basis and technical support for the quality inspection and performance optimization of the closing resistor. Summary of the Invention

[0010] The purpose of this invention is to overcome the problems in the prior art, such as insufficient modeling of the failure mechanism of the closing resistor, failure to consider the impact of end face flatness on performance, lack of local failure stress analysis, and lack of quantitative performance evaluation methods. This invention provides a simulation modeling method, system, and storage medium for the local failure principle of the closing resistor. It can not only accurately establish the numerical simulation model of the local failure principle of the closing resistor, but also evaluate the impact of the end face flatness of the closing resistor on the performance of the closing resistor, thus ensuring the stable operation of the power system.

[0011] The objective of this invention can be achieved through the following technical solutions: A simulation modeling method for the local failure principle of the closing resistor, the method comprising: Based on the microscopic modeling parameters of the closing resistor end face, a random curve of the end face is generated by a random curve generation formula to model the closing resistor end face and establish a microscopic morphology model of the end face. The electrical parameters of the closing resistor are set according to the material properties of the closing resistor, and a simulation numerical model of the local failure principle of the closing resistor is established in combination with the micro-morphology model of the end face. According to the preset experimental requirements, the impact current waveform of the simulation numerical model of the local damage principle of the closing resistor is set in sequence, and the simulation experimental conditions are set based on the actual working conditions to carry out the impact simulation experiment. During the simulation process, the temperature distribution and internal current distribution data of the simulation numerical model of the local failure principle of the closing resistor are obtained. The limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor are calculated. The simulation numerical model of the local failure principle of the closing resistor is optimized to complete the modeling.

[0012] Furthermore, the microscopic modeling parameters of the closing resistor end face include the outer diameter, inner diameter, and thickness of the closing resistor; the electrical parameters of the closing resistor include Young's modulus, coefficient of thermal expansion, density, conductivity, and specific heat capacity.

[0013] Furthermore, the expression for the formula for randomly generating curves is: in, Let x be the x-coordinate of the curve, and take the value of y. Its range is 0~55. These are the specific coordinates in the Z-direction of the closing resistor terminal face in spatial geometry. This is the scaling factor used in the Z direction. These are Gaussian random numbers with a normal distribution. Let D be a Gaussian random with a normal distribution, and let D be the length of the terminal face of the closing resistor. Let A be a normally distributed random variable with a normal distribution, N be the scaling factor, N be the spatial frequency resolution, and b be the frequency exponent parameter.

[0014] Furthermore, the aforementioned Use 3 random seed numbers, with a range of 1000. The Use 3 random seed numbers, with a range of 1000. The exist and The summation range of A is randomly selected from the given values; .

[0015] Furthermore, when establishing the micro-morphology model of the end face, the basic conditions of the random curve of the end face are also set, including the spatial frequency resolution and frequency exponent parameter. The micro-morphology model of the end face simulates the roughness characteristics of the end face based on the spatial frequency resolution and frequency exponent parameter.

[0016] Furthermore, the process of conducting the impact simulation experiment, based on actual working conditions and setting simulation experimental conditions, includes: Multiple inrush currents of different amplitudes and their flow times are preset. The upper copper electrode of the closing resistor is set as the terminal and the lower copper electrode is grounded. The inrush current is injected into the numerical simulation model of the local failure principle of the closing resistor. The temperature change and distribution and stress change and distribution of the closing resistor under different inrush current amplitudes are recorded.

[0017] Furthermore, in the impact simulation experiment, the temperature change and distribution and stress change and distribution of the electrical contact area between the closing resistor and the electrode are collected as simulation results. Based on the temperature distribution and internal current distribution data of the electrical contact area, the limit value of the impact current that the closing resistor can withstand and the limit value of the local damage stress of the closing resistor are calculated.

[0018] Furthermore, the process of optimizing the simulation numerical model of the local failure principle of the closing resistor includes: The calculated limit values ​​of the inrush current that the closing resistor can withstand and the limit values ​​of the local damage stress of the closing resistor are substituted into the simulation numerical model of the local damage principle of the closing resistor to verify the deviation between the calculated results of the micro-modeling parameters and electrical parameters and the actual closing resistor parameters. If the calculated temperature is too low or too high, adjust the conductivity and specific heat capacity of the closing resistor. If the calculated stress is too low or too high, adjust the Young's modulus and coefficient of thermal expansion. If the temperature or stress distribution in the electrical contact area does not match the actual value, adjust the spatial frequency resolution and frequency index parameters of the end face model, or change the Z-direction scaling factor and Gaussian random number seed of the random curve to optimize the simulation morphology of the micro-unevenness of the end face. If the response rate of the impact current does not match the actual value, adjust the time parameters of the impact current waveform to match the actual working condition within a fixed current flow time under the limit value. If the deviation between the optimized numerical model of the simulation of the local failure principle of the closing resistor and the actual closing resistor parameters is less than a preset threshold, then the optimization of the numerical model of the simulation of the local failure principle of the closing resistor is completed.

[0019] A simulation modeling system for the local failure principle of a closing resistor, the system comprising: The parameter acquisition unit is used to acquire the microscopic modeling parameters of the closing resistor end face and the material properties of the closing resistor, and to set the electrical parameters of the closing resistor based on the material properties of the closing resistor. The geometric modeling unit is used to generate random curves for the end face of the closing resistor based on the micro-modeling parameters of the closing resistor end face by using a random curve generation formula, and to establish a micro-morphological model of the end face. The electrical parameters of the closing resistor are set according to the material properties of the closing resistor, and a simulation numerical model of the local failure principle of the closing resistor is established in combination with the micro-morphological model of the end face. The simulation calculation unit is used to sequentially set the impact current waveform of the simulation numerical model of the local failure principle of the closing resistor according to the preset experimental requirements, and to set the simulation experimental conditions based on the actual working conditions to carry out the impact simulation experiment. The model optimization unit is used to acquire the temperature distribution and internal current distribution data of the simulation numerical model of the local failure principle of the closing resistor during the simulation process, calculate the limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor, optimize the simulation numerical model of the local failure principle of the closing resistor, and complete the modeling.

[0020] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the simulation modeling method for the principle of local damage to the closing resistor as described above.

[0021] Compared with the prior art, the beneficial effects of the present invention include: 1. This invention establishes a numerical simulation model that considers the microscopic morphological characteristics of the end face and uses a random curve formula to generate the end face roughness. This allows for an accurate assessment of the impact of end face flatness on the performance of the closing resistor. Compared with existing modeling methods that treat the end face as an ideal plane, the modeling accuracy of this invention is significantly improved, and it can accurately predict local failure modes and causes.

[0022] 2. By selecting the electrical contact area for local temperature and stress analysis, this invention reveals the mechanism of local overheating at the electrical contact point leading to overall failure, and accurately determines the cause and key location of the failure of the closing resistor.

[0023] 3. This invention provides a quantitative evaluation method for the quality inspection and performance optimization of closing resistors by calculating the inrush current limit and local destructive stress limit that the closing resistor can withstand, and determines the inrush current limit, thus providing an accurate theoretical basis and technical support for ensuring the stable operation of the power system.

[0024] 4. By setting different spatial frequency resolutions and frequency index parameters, this invention can flexibly adjust the degree of end-face roughness to adapt to different simulation requirements, and can cover the main roughness characteristics of the closing resistor end face. The modeling method has good applicability and scalability. Attached Figure Description

[0025] Figure 1 This is a flowchart of the method of the present invention.

[0026] Figure 2 This is a schematic diagram of the closing resistor modeling in an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of end face modeling with different parameters according to an embodiment of the present invention.

[0028] Figure 4 This is a simulation diagram of the inrush current according to an embodiment of the present invention.

[0029] Figure 5 This is a temperature distribution diagram of the closing resistor in an embodiment of the present invention.

[0030] Figure 6 This is a schematic diagram of the internal current distribution of the closing resistor in an embodiment of the present invention.

[0031] Figure 7 This is a graph showing the average temperature variation in the region where the closing resistor is selected in an embodiment of the present invention.

[0032] Figure 8 This is a diagram showing the average stress variation in the selected area of ​​the closing resistor in an embodiment of the present invention. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0034] Example 1 This embodiment discloses a simulation modeling method for the local failure principle of the closing resistor, the method is as follows: Figure 1 As shown, steps S1-S5 are included, and each step is described in detail below: Step S1: Obtain the microscopic modeling parameters of the closing resistor end face and the material properties of the closing resistor.

[0035] The microscopic modeling parameters of the closing resistor end face include the outer diameter, inner diameter, and thickness of the closing resistor.

[0036] The electrical parameters of the closing resistor include Young's modulus, coefficient of thermal expansion, density, conductivity, and specific heat capacity.

[0037] Step S2: Based on the microscopic modeling parameters of the closing resistor end face, a random curve of the end face is generated by a random curve generation formula to model the end face of the closing resistor and establish a microscopic morphology model of the end face; the electrical parameters of the closing resistor are set according to the material properties of the closing resistor, and a simulation numerical model of the local failure principle of the closing resistor is established in combination with the microscopic morphology model of the end face.

[0038] The formula for randomly generating curves is as follows: and ,in For all indices from low to high, the general expression was calculated. The sum, conditional expression The calculation result is and One of them, depending on the value of the condition.

[0039] When establishing the micro-morphology model of the end face, the basic conditions of the random curve of the end face are also set, including the spatial frequency resolution and frequency exponent parameter. The micro-morphology model of the end face simulates the roughness characteristics of the end face based on the spatial frequency resolution and frequency exponent parameter.

[0040] The specific expression for the formula for randomly generating curves is: in, Let x be the x-coordinate of the curve, and take the value of y. Its range is 0~55. These are the specific coordinates in the Z-direction of the closing resistor terminal face in spatial geometry. This is the scaling factor used in the Z direction. These are Gaussian random numbers with a normal distribution. Let D be a Gaussian random with a normal distribution, and let D be the length of the terminal face of the closing resistor. Let A be a normally distributed random variable with a normal distribution, N be the scaling factor, N be the spatial frequency resolution, and b be the frequency exponent parameter.

[0041] Use 3 random seed numbers, with a range of 1000. ; Use 3 random seed numbers, with a range of 1000. ; exist and The summation of A is randomly selected from the range of values; the range of A is... .

[0042] Step S3: According to the preset experimental requirements, set the impact current waveform of the simulation numerical model of the local damage principle of the closing resistor in sequence, and set the simulation experimental conditions based on the actual working conditions to carry out the impact simulation experiment.

[0043] The process of conducting impact simulation experiments based on actual working conditions includes: Multiple inrush currents of different amplitudes and their flow times are preset. The upper copper electrode of the closing resistor is set as the terminal and the lower copper electrode is grounded. Inrush current is injected into the simulation numerical model of the local failure principle of the closing resistor. The temperature change and distribution and stress change and distribution of the closing resistor under different amplitude inrush currents are recorded.

[0044] In the impact simulation experiment, the temperature change and distribution and stress change and distribution of the electrical contact area between the closing resistor and the electrode are mainly collected as simulation results. Based on the temperature distribution and internal current distribution data of the electrical contact area, the limit value of the impact current that the closing resistor can withstand and the limit value of the local damage stress of the closing resistor are calculated.

[0045] Step S4: Obtain the temperature distribution and internal current distribution data of the simulation numerical model of the local failure principle of the closing resistor during the simulation process, calculate the limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor, compare and determine whether there is a defect in the closing resistor, and optimize the simulation numerical model of the local failure principle of the closing resistor.

[0046] The process of optimizing the simulation numerical model of the local failure principle of the closing resistor includes: The calculated limit values ​​of the closing resistor's ability to withstand impact current and the limit values ​​of the local failure stress of the closing resistor are substituted into the numerical simulation model of the local failure principle of the closing resistor to verify the deviation between the calculated results of the microscopic modeling parameters and electrical parameters and the actual closing resistor parameters.

[0047] If the calculated temperature is too low or too high, adjust the conductivity and specific heat capacity of the closing resistor. If the calculated stress is too low or too high, adjust the Young's modulus and coefficient of thermal expansion. If the temperature or stress distribution in the electrical contact area does not match the actual value, adjust the spatial frequency resolution and frequency index parameters of the end face model, or change the Z-direction scaling factor and Gaussian random number seed of the random curve to optimize the simulation morphology of the micro-unevenness of the end face. If the response rate of the impact current does not match the actual value, adjust the time parameters of the impact current waveform to match the actual working condition within a fixed current flow time under the limit value.

[0048] If the deviation between the optimized numerical model for the local failure principle of the closing resistor and the actual closing resistor parameters is less than a preset threshold, then the optimization of the numerical model for the local failure principle of the closing resistor is complete.

[0049] Step S5: After optimization, numerical simulation stress calculation is performed on the closing resistor again, and the maximum value of thermal stress at the current injection point is compared with the standard compressive strength. If not, the amplitude and waveform of the impact current are adjusted, and numerical simulation stress calculation is performed on the closing resistor again. If so, the maximum value of the impact current that the closing resistor can withstand is calculated, and the final numerical simulation model of local failure of the closing resistor is output.

[0050] Example 2 This embodiment is based on the simulation modeling method of the local damage principle of the closing resistor disclosed in Embodiment 1 above, and provides a practical application example.

[0051] The actual end face of the closing resistor is used as the microscopic modeling reference parameters for the principle of local damage of the closing resistor, including the outer diameter (r1: 151±1mm), inner diameter (r0: 41±0.5mm), thickness (L: 25.4±0.3), and surface roughness of the closing resistor.

[0052] Modeling the half-section of the closing resistor as follows Figure 2 As shown, where: In the formula, D is the width of half the cross section of the closing resistor.

[0053] Figure 2 The copper electrode is 67mm long and 10mm thick, and both have a 1mm bevel.

[0054] The formula for the random curve of the closing resistor terminal face is as follows: In the formula: This is the scaling factor used in the Z direction. The random number is Gaussian, the distribution is normally distributed, and three random seed numbers are used, ranging from 0 to 1. The random number is Gaussian, and the distribution is also normally distributed. Three random seed numbers are used, ranging from 0 to D, where D is the length of the end face of the closing resistor. It is a normally distributed random event, and its distribution is normally distributed. and Randomly selected values ​​between, with different roughnesses determined by the spatial frequency resolution in the formula: Sum frequency index parameter: The decision was made.

[0055] Geometric modeling of the closing resistor terminal face with changes in spatial frequency resolution and frequency index parameters, such as... Figure 3 As shown, from left to right, the spatial frequency resolution is 20, and the frequency index parameters are 0.8, 1.0, and 1.5 respectively. The frequency index parameter is 1.0, and the spatial frequency resolution is 15, 20, and 25 respectively. Based on the actual situation of the closing resistor terminal face and combined with electrical contact theory, appropriate spatial frequency resolution and frequency index parameters are selected. The following section models a random curve of the closing resistor terminal face with a spatial frequency resolution of 20 and a frequency index parameter of 1.0.

[0056] The embodiment uses four different amplitude impulse currents with a flow time of 10ms, such as... Figure 4 As shown, by setting different impact currents, the temperature changes and distribution and stress changes and distribution are analyzed to verify the accuracy of the simulation calculation model of the local failure principle of the closing resistor.

[0057] By setting the upper copper electrode as the terminal, injection is performed. Figure 4 The inrush current, with the lower copper electrode grounded, is used to simulate and analyze the local failure principle of the closing resistor. The temperature distribution of the closing resistor is as follows: Figure 5 As shown, the high-temperature areas are mainly concentrated in the contact area between the closing resistor and the copper electrode, i.e., the electrical contact area. Under an injection current amplitude of 2.0 kA, the maximum temperature of the closing resistor reached 347℃, while the minimum temperature was only 156℃. This indicates a severe imbalance in the internal temperature distribution of the closing resistor, suggesting that the failure was caused by excessive local stress due to localized overheating, leading to localized damage. Combined with... Figure 6 The current distribution of the closing resistor fully demonstrates that the direction and distribution of the inrush current affect the temperature changes at the end face and inside the closing resistor.

[0058] By setting the upper copper electrode as the terminal, injection is performed. Figure 4 The inrush current, with the lower copper electrode grounded, is used to simulate and analyze the local failure principle of the closing resistor. The temperature distribution of the closing resistor is as follows: Figure 5As shown, the high-temperature areas are mainly concentrated in the contact area between the closing resistor and the copper electrode, i.e., the electrical contact area. Under an injection current amplitude of 2.0 kA, the maximum temperature of the closing resistor reached 347℃, while the minimum temperature was only 156℃. This indicates a severe imbalance in the internal temperature distribution of the closing resistor, suggesting that the failure was caused by excessive local stress due to localized overheating, leading to localized damage. Combined with... Figure 6 The current distribution of the closing resistor fully demonstrates that the direction and distribution of the inrush current affect the temperature changes at the end face and inside the closing resistor.

[0059] Select Figure 2 To analyze the electrical contact area, firstly, the average temperature change of the area is selected as follows: Figure 7 As shown in the figure, the average temperature of the selected area is 260.2℃ under an impulse current injection of 2.0kA, which is 204℃ higher than the average temperature under an impulse current injection of 1.0kA. Comparing the trend of the average temperature change with the trend of the impulse current change, it can be seen that the temperature change of the closing resistor is basically consistent with the change of the impulse current, reflecting the rapid temperature response of the closing resistor.

[0060] like Figure 8 As shown, the average stress variation trend in the selected area is highly similar to the temperature variation trend. However, the average stress variation trend of the closing resistor exhibits a 0.1 ms lag. This is because the temperature change causes thermal expansion within the closing resistor, leading to changes in its thermal stress. Under a 2.0 kA impulse current injection, the maximum average stress of the closing resistor reaches 1.25 × 10⁻⁶. 8 N / m 2 The stress has reached the material stress of the closing resistor itself (1.2 × 10⁻⁶). 8 N / m 2 Measurements revealed that the stress value at the electrical contact point of the closing resistor reached 1.48 × 10⁻⁶. 8 N / m 2 The stress was significantly higher than that of the closing resistor material, which clearly indicates that the failure of the closing resistor was caused by local overheating at the electrical contact point, leading to the overall failure of the closing resistor.

[0061] In the above analysis, the limit value of the impact current for local damage to the closing resistor is 2.0kA. When an impact current with a current carrying time of 10ms and an amplitude of 2.0kA is applied, the local stress value inside the closing resistor will be too large and the temperature will be too high, causing local damage to the closing resistor and ultimately leading to the failure of the closing resistor.

[0062] Example 3 This embodiment, based on Embodiment 1 above, discloses a simulation modeling system for the local failure principle of the closing resistor. The system includes: The parameter acquisition unit is used to acquire the microscopic modeling parameters of the closing resistor end face and the material properties of the closing resistor, and to set the electrical parameters of the closing resistor based on the material properties of the closing resistor.

[0063] The geometric modeling unit is used to model the end face of the closing resistor based on the microscopic modeling parameters of the closing resistor end face by generating random curves through random curve generation formulas, and establishing a microscopic morphology model of the end face. The electrical parameters of the closing resistor are set according to the material properties of the closing resistor, and a numerical simulation model of the local failure principle of the closing resistor is established in combination with the microscopic morphology model of the end face.

[0064] The simulation calculation unit is used to set the impact current waveform of the simulation numerical model of the local failure principle of the closing resistor according to the preset experimental requirements, and to set the simulation experimental conditions based on the actual working conditions to carry out the impact simulation experiment.

[0065] The model optimization unit is used to acquire the temperature distribution and internal current distribution data of the simulation numerical model of the local failure principle of the closing resistor during the simulation process, calculate the limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor, optimize the simulation numerical model of the local failure principle of the closing resistor, and complete the modeling.

[0066] For specific details of the above-mentioned units, please refer to the relevant descriptions and effects in Embodiment 1 for understanding.

[0067] Example 4 Based on Embodiment 1, this embodiment provides an electronic device, including: one or more processors and a memory, wherein the memory stores one or more programs, and the one or more programs include instructions for executing the simulation modeling method for the local failure principle of the closing resistor as described above.

[0068] At the hardware level, the electronic device includes a processor, internal bus, network interface, memory, and non-volatile memory, and may also include other hardware required for business operations. The processor reads the corresponding computer program from the non-volatile memory into memory and then runs it to implement the simulation modeling method for the local damage principle of the closing resistor described above. Of course, in addition to software implementation, this invention does not exclude other implementation methods, such as logic devices or a combination of hardware and software, etc. That is to say, the execution subject of the following processing flow is not limited to individual logic units, but can also be hardware or logic devices.

[0069] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0070] Computer-readable media include both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0071] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A simulation modeling method for the principle of local damage to the closing resistor, characterized in that, The method includes: Based on the microscopic modeling parameters of the closing resistor end face, a random curve of the end face is generated by a random curve generation formula to model the closing resistor end face and establish a microscopic morphology model of the end face. The electrical parameters of the closing resistor are set according to the material properties of the closing resistor, and a simulation numerical model of the local failure principle of the closing resistor is established in combination with the micro-morphology model of the end face. According to the preset experimental requirements, the impact current waveform of the simulation numerical model of the local damage principle of the closing resistor is set in sequence, and the simulation experimental conditions are set based on the actual working conditions to carry out the impact simulation experiment. During the simulation process, the temperature distribution and internal current distribution data of the simulation numerical model of the local failure principle of the closing resistor are obtained. The limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor are calculated. The simulation numerical model of the local failure principle of the closing resistor is optimized to complete the modeling.

2. The simulation modeling method for the local failure principle of the closing resistor according to claim 1, characterized in that, The microscopic modeling parameters of the closing resistor end face include the outer diameter, inner diameter, and thickness of the closing resistor; the electrical parameters of the closing resistor include Young's modulus, coefficient of thermal expansion, density, conductivity, and specific heat capacity.

3. The simulation modeling method for the local failure principle of the closing resistor according to claim 1, characterized in that, The expression for the formula for randomly generating curves is: in, Let be the x-coordinate of the curve, and take the value . Its range is 0~55. These are the specific coordinates in the Z-direction of the closing resistor terminal face in spatial geometry. This is the scaling factor used in the Z direction. These are Gaussian random numbers with a normal distribution. Let D be a Gaussian random with a normal distribution, and let D be the length of the terminal face of the closing resistor. Let A be a normally distributed random variable with a normal distribution, N be the scaling factor, N be the spatial frequency resolution, and b be the frequency exponent parameter.

4. The simulation modeling method for the local failure principle of the closing resistor according to claim 3, characterized in that, The Use 3 random seed numbers, ranging from The Use 3 random seed numbers, ranging from The exist and The summation range of A is randomly selected from the given values; .

5. The simulation modeling method for the local failure principle of the closing resistor according to claim 1, characterized in that, When establishing the micro-morphology model of the end face, the basic conditions of the random curve of the end face are also set, including the spatial frequency resolution and frequency exponent parameter. The micro-morphology model of the end face simulates the roughness characteristics of the end face based on the spatial frequency resolution and frequency exponent parameter.

6. The simulation modeling method for the local failure principle of the closing resistor according to claim 1, characterized in that, The process of conducting the impact simulation experiment based on actual working conditions includes setting simulation experimental conditions as follows: Multiple inrush currents of different amplitudes and their flow times are preset. The upper copper electrode of the closing resistor is set as the terminal and the lower copper electrode is grounded. The inrush current is injected into the numerical simulation model of the local failure principle of the closing resistor. The temperature change and distribution and stress change and distribution of the closing resistor under different inrush current amplitudes are recorded.

7. The simulation modeling method for the local failure principle of the closing resistor according to claim 1, characterized in that, In the impact simulation experiment, the temperature change and distribution and stress change and distribution of the electrical contact area between the closing resistor and the electrode are collected as simulation results. Based on the temperature distribution and internal current distribution data of the electrical contact area, the limit value of the impact current that the closing resistor can withstand and the limit value of the local damage stress of the closing resistor are calculated.

8. The simulation modeling method for the local failure principle of the closing resistor according to claim 1, characterized in that, The process of optimizing the simulation numerical model of the local failure principle of the closing resistor includes: The calculated limit values ​​of the inrush current that the closing resistor can withstand and the limit values ​​of the local damage stress of the closing resistor are substituted into the simulation numerical model of the local damage principle of the closing resistor to verify the deviation between the calculated results of the micro-modeling parameters and electrical parameters and the actual closing resistor parameters. If the calculated temperature is too low or too high, adjust the conductivity and specific heat capacity of the closing resistor. If the calculated stress is too low or too high, adjust the Young's modulus and coefficient of thermal expansion. If the temperature or stress distribution in the electrical contact area does not match the actual value, adjust the spatial frequency resolution and frequency index parameters of the end face model, or change the Z-direction scaling factor and Gaussian random number seed of the random curve to optimize the simulation morphology of the micro-unevenness of the end face. If the response rate of the impact current does not match the actual value, adjust the time parameters of the impact current waveform to match the actual working condition within a fixed current flow time under the limit value. If the deviation between the optimized numerical model of the simulation of the local failure principle of the closing resistor and the actual closing resistor parameters is less than a preset threshold, then the optimization of the numerical model of the simulation of the local failure principle of the closing resistor is completed.

9. A simulation modeling system for the principle of local damage to closing resistor, characterized in that, The system includes: The parameter acquisition unit is used to acquire the microscopic modeling parameters of the closing resistor end face and the material properties of the closing resistor, and to set the electrical parameters of the closing resistor based on the material properties of the closing resistor. The geometric modeling unit is used to generate random curves for the end face of the closing resistor based on the micro-modeling parameters of the closing resistor end face by using a random curve generation formula, and to establish a micro-morphological model of the end face. The electrical parameters of the closing resistor are set according to the material properties of the closing resistor, and a simulation numerical model of the local failure principle of the closing resistor is established in combination with the micro-morphological model of the end face. The simulation calculation unit is used to sequentially set the impact current waveform of the simulation numerical model of the local failure principle of the closing resistor according to the preset experimental requirements, and to set the simulation experimental conditions based on the actual working conditions to carry out the impact simulation experiment. The model optimization unit is used to acquire the temperature distribution and internal current distribution data of the simulation numerical model of the local failure principle of the closing resistor during the simulation process, calculate the limit value of the impact current that the closing resistor can withstand and the limit value of the local failure stress of the closing resistor, optimize the simulation numerical model of the local failure principle of the closing resistor, and complete the modeling.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the simulation modeling method for the principle of local damage of the closing resistor as described in any one of claims 1-8.

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