Large-current arc breaking test simulation nozzle size parameterization modeling method and system

Abstract

The application belongs to the technical field of circuit breaker research and development, and particularly relates to a large-current arc breaking test simulation nozzle size parameterized modeling method and system, which establishes a two-dimensional axisymmetric geometric model and extracts an initial throat radius, extracts an airflow velocity at a throat wall, an arc current and an action time after running a heat-flow coupling simulation, calculates an ablation amount according to a formula in combination with an ablation constant, and automatically updates the throat radius and the geometric model according to the ablation amount; subsequently, the original grid is automatically removed and is redrawn according to an updated domain, an original boundary condition is mapped to a new grid, and simulation is continued to obtain breaking characteristics at each time step; after all time steps are completed, a calculated value and a measured value are compared, and if a deviation exceeds a threshold value, the ablation constant is adjusted for recalculation. The method realizes automatic parameter updating and grid reconstruction based on physical ablation, avoids manual repeated modeling, significantly improves simulation efficiency, and solves the problems of low automation and complicated steps in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of circuit breaker research and development technology, specifically relating to a parameterized modeling method and system for nozzle size in high-current arc breaking test simulation. Background Technology

[0002] In high-voltage circuit breakers, the nozzle is the core component for achieving gas-blown arc extinguishing. When the circuit breaker interrupts a short-circuit current, an electric arc burns between the contacts, releasing a large amount of heat. The high-temperature arc causes thermal decomposition of the surrounding gaseous medium (usually SF6 or compressed air), generating plasma. This plasma undergoes intense heat exchange with the cold airflow at the nozzle throat, and the arc energy is carried away by the cold airflow, thus extinguishing the arc. Figure 1 This is a schematic diagram of airflow extinguishing in a circuit breaker.

[0003] With increasing number of interruptions, the nozzle throat undergoes ablation under the combined effects of high-temperature arc and high-speed airflow. Ablation includes two mechanisms: thermochemical ablation (material decomposition and evaporation at high temperatures) and mechanical erosion (abrasion of the material surface by high-speed airflow). Ablation directly leads to an increase in the inner diameter of the nozzle throat, altering the airflow field distribution in the arc-extinguishing chamber and affecting the circuit breaker's breaking performance.

[0004] In high-current arc breaking test simulations, various arcing modes, such as short-arc, medium-arc, and long-arc, are required to simulate actual operating conditions. Since the nozzle throat undergoes ablation after each test, the nozzle throat dimensions differ depending on the test mode. Traditional methods require establishing separate geometric and finite element models for each test mode, which not only increases the workload for engineers but also prolongs the simulation cycle. Existing technology CN110147559A discloses a multi-physics coupling-based multidisciplinary optimization design method for converters. However, this method's parametric modeling primarily focuses on the design optimization of the converter's heat dissipation structure, and its application scenario is steady-state thermal simulation, not addressing the time-varying geometric dimension updates caused by arc ablation. It is suitable for the optimization design of static geometric structures, where geometric parameters remain constant during simulation. However, in high-current arc breaking tests, the nozzle throat is continuously subjected to the arc thermal effect and airflow scouring, causing the throat radius to continuously increase over time. This time-varying geometric characteristic is not considered in existing technologies. Furthermore, this method only establishes a numerical relationship between geometric dimensions and the optimization objective, without establishing a physical connection between the ablation amount and operating parameters such as arc current and airflow velocity. Also, parametric modeling and simulation calculation are two independent processes; simulation results need to be manually extracted and then input into the parametric model for updates. Summary of the Invention

[0005] The purpose of this invention is to provide a parameterized modeling method and system for nozzle size in high-current arc breaking test simulation, so as to solve the technical problems of low simulation efficiency, inability to achieve automatic parameter updates based on physical laws, and cumbersome steps with low degree of automation in the existing technology.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for parametric modeling of nozzle dimensions in a high-current arc breaking test simulation, comprising: Obtain the actual structural dimensions of the circuit breaker nozzle, and establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body and throat region based on the actual structural dimensions of the circuit breaker nozzle; In a two-dimensional axisymmetric geometric model, the key node positions at the throat are marked, and the initial throat radius parameter is extracted; The two-dimensional axisymmetric geometric model is meshed, boundary conditions and initial conditions are set sequentially, and thermal-fluid coupling simulation is run to obtain the simulation results at the current time step; Based on the simulation results of the current time step, the airflow velocity, arc current and arc duration at the throat wall are extracted, and the ablation constant is determined. The throat ablation amount is calculated based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The initial throat radius parameter is updated based on the throat ablation amount, and the corresponding simulation geometric model is obtained. After re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed mesh, a thermal-fluid coupling simulation was run to obtain the high-current arc breaking characteristics of the next time step. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

[0007] Optionally, the parameterized model for the nozzle throat dimensions is specifically as follows:

[0008] In the formula, This represents the initial throat radius parameter; Indicates the radius of the nozzle throat at time t; Indicates the ablation constant; Indicates the airflow velocity at the throat wall; This represents a function of arc current as a function of time. Indicates the duration of the electric arc.

[0009] Optionally, a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body, and throat region is established in CAD software based on the actual structural dimensions of the circuit breaker nozzle. The key node positions at the throat are marked in the two-dimensional axisymmetric geometric model, specifically the starting point of the upstream contraction section of the nozzle, the intersection of the upstream contraction section of the nozzle and the straight section of the throat, the intersection of the straight section of the throat and the downstream expansion section, the ending point of the downstream expansion section of the nozzle, and the radial coordinates of the intersection of the upstream contraction section of the nozzle and the straight section of the throat and the intersection of the straight section of the throat and the downstream expansion section are used as the initial throat radius parameters.

[0010] Optionally, the two-dimensional axisymmetric geometric model is imported into the electric arc simulation analysis software, and the two-dimensional axisymmetric geometric model is sequentially meshed, and the boundary conditions and initial conditions are set. Then, the thermal-fluid coupling simulation calculation is run to obtain the initial simulation calculation results.

[0011] Alternatively, the arc simulation analysis software can be fluid software such as Fluent, or a combination of fluid and electromagnetic field software, such as a combination of Fluent and Maxwell, or COMSOL multiphysics coupling.

[0012] Optionally, the step of extracting the airflow velocity, arc current, and arc duration at the throat wall based on the simulation results of the current time step specifically involves: exporting the gas velocity, arc current, and arc duration at the throat to an ASCII file. The gas velocity at the throat is the average gas velocity obtained by integrating the gas velocity of the grid cells on the throat surface and dividing by the number of grid cells, as shown in the following formula:

[0013] In the formula, n This represents the number of grid cells for the straight segment of the throat. This represents the average gas flow rate; The gas velocity of the grid cells on the throat surface; The arc current is the current instantaneous value of the current boundary conditions in the simulation calculation. The arc duration is the current fluid time. In the formula, It is the arc current; This represents the peak current.

[0014] Optionally, CAD software is used to read the ASCII file and extract the gas flow rate, arc current, and arc duration. The throat ablation amount is calculated based on the gas flow rate, arc current, and arc duration. The nozzle throat diameter is adjusted according to the throat ablation amount. Specifically, the coordinates of the intersection points of the upstream and downstream sides with the throat are updated, and then the points are reconnected to update the nozzle inner surface shape, thus obtaining the corresponding simulation geometric model.

[0015] Optionally, after re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed grid, a thermal-fluid coupled simulation is run to obtain the high-current arc breaking characteristics under the current operating condition, specifically: The original mesh is automatically cleared, and a new finite element mesh is generated based on the boundaries of the flow field region and the solid region in the simulation geometry model, according to the preset mesh parameters. Extract various boundary conditions that have been set on the two-dimensional axisymmetric geometric model, including inlet pressure, outlet pressure and initial temperature, and automatically associate and assign the boundary conditions to the corresponding boundaries of the finite element mesh according to the boundary name or spatial location correspondence. Run thermal-fluid coupling simulation calculations and output the curves of arc voltage, arc conductivity and temperature distribution at the nozzle throat under the current operating conditions as a function of time, which serve as the high-current arc breaking characteristics. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset value, the calculation ends. If the deviation is greater than the preset value, the ablation constant is adjusted and the simulation calculation is performed again.

[0016] In a second aspect, the present invention provides a parameterized modeling system for nozzle dimensions in a high-current arc breaking test simulation, comprising: The geometric modeling unit is used to obtain the actual structural dimensions of the circuit breaker nozzle and to establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body and throat area based on the actual structural dimensions of the circuit breaker nozzle. The parameter extraction unit is used to mark the key node positions at the throat in the two-dimensional axisymmetric geometric model and extract the initial throat radius parameter; The simulation calculation unit is used to sequentially mesh the two-dimensional axisymmetric geometric model, set the boundary conditions and initial conditions, and run the thermal-fluid coupling simulation calculation to obtain the simulation calculation results of the current time step; The simulation parameter extraction unit is used to extract the airflow velocity, arc current and arc duration at the throat wall based on the simulation calculation results of the current time step, and to determine the ablation constant. The parametric modeling unit is used to calculate the throat ablation based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The model update unit is used to update the initial throat radius parameter according to the throat ablation amount, and to update the corresponding simulation geometric model. The updated simulation calculation unit is used to re-mesh the simulation geometric model and map the boundary conditions of the two-dimensional axisymmetric geometric model to the re-mesh. Then, it runs the thermal-fluid coupling simulation calculation to obtain the high-current arc breaking characteristics of the next time step. The judgment unit is used to compare the calculated value with the measured value after all time steps have been calculated. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

[0017] In a third aspect, the present invention provides an electronic device, including a processor and a memory, wherein the processor is configured to execute a computer program stored in the memory to implement a parameterized modeling method for nozzle size in a high-current arc breaking test simulation as described in any one of the preceding claims.

[0018] In a fourth aspect, the present invention provides a computer-readable storage medium storing at least one instruction, wherein when executed by a processor, the at least one instruction implements the method for parameterized modeling of nozzle size in a high-current arc breaking test simulation as described in any one of the preceding claims.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: This application discloses a parameterized modeling method for nozzle dimensions in high-current arc breaking test simulations. It establishes a two-dimensional axisymmetric geometric model including key structures and extracts the initial throat radius, providing accurate reference parameters for subsequent dynamic updates. Based on this, it extracts the airflow velocity, arc current, and duration at the throat wall in real time from the simulation results, and quantitatively calculates the throat ablation amount using the ablation constant. This allows the throat dimensions to be automatically updated during the arc process, avoiding manual remodeling and mesh re-division due to ablation, significantly shortening the simulation cycle. Simultaneously, the updated geometric model automatically re-meshes and maps the original boundary conditions to the new mesh, ensuring computational continuity and reducing human error. Furthermore, by comparing the calculation results of all time steps with measured values ​​and adaptively adjusting the ablation constant based on the deviation before resimulating, a closed-loop verification mechanism is formed, effectively improving the accuracy of high-current arc breaking characteristic prediction and the reliability of the simulation model.

[0020] Furthermore, by establishing a two-dimensional axisymmetric geometric model containing key structures and accurately extracting the initial throat radius parameters, a reliable benchmark is provided for subsequent dynamic simulations. Based on this, a parameterized model of the nozzle throat dimensions is used to quantitatively couple the real-time extracted airflow velocity at the throat wall, time-varying arc current, material ablation constant, and action time. This enables accurate calculation of the throat ablation amount at any given time, achieving automatic updating of the throat dimensions as the arc progresses. This fundamentally avoids manual remodeling and mesh remapping caused by ablation, significantly shortening the cycle of high-current arc breaking simulation experiments. Simultaneously, the updated geometric model automatically completes mesh remapping and inherits the original boundary conditions, ensuring the continuity and consistency of multi-time-step simulations and effectively reducing errors introduced by human operation. Furthermore, by comparing the calculation results of all time steps with measured values ​​and adaptively adjusting the ablation constant based on the deviation before iterating again, a closed-loop self-calibration verification mechanism based on this mathematical model is formed. This significantly enhances the adaptability and long-term reliability of the simulation model to different operating conditions while improving the prediction accuracy of high-current arc breaking characteristics. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of airflow extinguishing in a circuit breaker. Figure 2 This is a flowchart illustrating an embodiment of the present invention; Figure 3 This is a system structure block diagram according to an embodiment of the present invention; Figure 4 This is a structural block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0023] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0024] See Figure 2 This application discloses a parameterized modeling method for nozzle size in high-current arc breaking test simulation, including: Obtain the actual structural dimensions of the circuit breaker nozzle, and establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body and throat region based on the actual structural dimensions of the circuit breaker nozzle; In a two-dimensional axisymmetric geometric model, the key node positions at the throat are marked, and the initial throat radius parameter is extracted; The two-dimensional axisymmetric geometric model is meshed, boundary conditions and initial conditions are set sequentially, and thermal-fluid coupling simulation is run to obtain the simulation results at the current time step; Based on the simulation results of the current time step, the airflow velocity, arc current and arc duration at the throat wall are extracted, and the ablation constant is determined. The throat ablation amount is calculated based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The initial throat radius parameter is updated based on the throat ablation amount, and the corresponding simulation geometric model is obtained. After re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed mesh, a thermal-fluid coupling simulation was run to obtain the high-current arc breaking characteristics of the next time step. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

[0025] By establishing a two-dimensional axisymmetric geometric model and extracting the initial throat radius, and combining thermal-fluid coupling simulation to obtain key parameters such as airflow velocity and arc current in real time, the throat size is quantitatively updated using the ablation calculation formula. This achieves automatic parametric modeling and adaptive mesh updating of the nozzle ablation process, completely eliminating the tedious steps of manual remodeling and re-meshing, and significantly shortening the overall cycle of the arc breaking simulation test. At the same time, the automatic inheritance of the original boundary conditions ensures the continuity and consistency of multi-time-step calculations, effectively reducing human error. Furthermore, by comparing the simulation results with the measured values ​​in a closed loop and adaptively adjusting the ablation constant according to the deviation, a self-verification and correction mechanism is formed, further improving the accuracy of simulation predictions and the model's adaptability to different working conditions.

[0026] In some embodiments, the nozzle throat size parameterization model is specifically:

[0027] In the formula, This represents the initial throat radius parameter; Indicates the radius of the nozzle throat at time t; Indicates the ablation constant; Indicates the airflow velocity at the throat wall; This represents a function of arc current as a function of time. Indicates the duration of the electric arc.

[0028] By leveraging a two-dimensional axisymmetric geometric model and thermo-fluid coupling simulation, parameters such as airflow velocity and arc current at the throat wall are extracted in real time. The ablation amount is then accurately calculated using formulas, and the throat size and mesh are automatically updated, completely eliminating the need for manual remodeling and mesh redrawing, thus significantly shortening the simulation cycle. At the same time, the automatic inheritance of the original boundary conditions ensures the continuity of the calculation, and the closed-loop comparison between the simulated and measured values ​​and the adaptive adjustment of the ablation constant further improve the prediction accuracy and the model's adaptability to different working conditions.

[0029] In some embodiments, a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body, and throat region is established in CAD software based on the actual structural dimensions of the circuit breaker nozzle. The key node positions at the throat are marked in the two-dimensional axisymmetric geometric model, specifically: the starting point of the upstream contraction section of the nozzle, the intersection of the upstream contraction section and the straight throat segment, the intersection of the straight throat segment and the downstream expansion section, the ending point of the downstream expansion section, and the radial coordinates of the intersections of the upstream contraction section and the straight throat segment, and the intersection of the straight throat segment and the downstream expansion section, which serve as the initial throat radius parameter. By accurately establishing the two-dimensional axisymmetric geometric model and extracting the initial throat radius in the CAD software, a reliable benchmark is provided for subsequent automatic size updates and mesh remapping based on the ablation formula, thereby completely avoiding manual repetitive modeling and significantly shortening the simulation cycle. Simultaneously, through closed-loop comparison and adaptive adjustment of the ablation constant, the prediction accuracy and model adaptability are effectively improved.

[0030] In some embodiments, a two-dimensional axisymmetric geometric model is imported into arc simulation analysis software. Mesh generation, boundary conditions, and initial conditions are then set sequentially for the two-dimensional axisymmetric geometric model, and a thermo-fluid coupled simulation is run to obtain initial simulation results. By importing the two-dimensional axisymmetric geometric model into the arc simulation analysis software, the integrated setting of mesh generation, boundary conditions, and initial conditions is completed, and a thermo-fluid coupled simulation is run to obtain initial simulation results. This provides a continuous and reliable computational foundation for subsequent quantitative calculation of throat ablation and automatic size updates. It avoids the time consumption and operational errors caused by repeatedly manually setting preprocessing parameters due to model adjustments in traditional methods, further ensuring the automated connection of the simulation process and the stability of computational accuracy.

[0031] In some embodiments, extracting the airflow velocity, arc current, and arc duration at the throat wall based on the simulation results of the current time step specifically involves: exporting the gas velocity, arc current, and arc duration at the throat to an ASCII file. The gas velocity at the throat is the average gas velocity obtained by integrating the gas velocity of the grid cells on the throat surface and dividing it by the number of grid cells, as shown in the following formula:

[0032] In the formula, n This represents the number of grid cells for the straight segment of the throat. This represents the average gas flow rate; The gas velocity of the grid cells on the throat surface; The arc current is the current instantaneous value of the current boundary conditions in the simulation calculation. The arc duration is the current fluid time. In the formula, It is the arc current; The peak current is represented by the parameter. By accurately exporting the airflow velocity at the throat (measured as the integral average of the velocity of the surface grid cells), the instantaneous value of the arc current, and the current fluid time to an ASCII file, accurate and standardized input parameters are provided for quantitative calculation based on the ablation formula, thus ensuring the reliability of the throat ablation calculation. This automated parameter extraction method eliminates the need for manual reading and input, further improving the continuity of the simulation process and the efficiency of data processing. In conjunction with the subsequent adaptive grid update and closed-loop comparison mechanism, it jointly ensures the accuracy of the prediction of high-current arc breaking characteristics and the robust adaptability of the model to different working conditions.

[0033] In some embodiments, CAD software is used to read ASCII files and extract gas velocity, arc current, and arc duration. Based on these parameters, the throat ablation amount is calculated, and the nozzle throat diameter is adjusted accordingly. Specifically, the coordinates of the upstream and downstream intersections with the throat are updated, and the nozzle inner surface shape is updated, resulting in the corresponding simulation geometric model. By automatically reading the gas velocity, arc current, and duration from the ASCII files using CAD software and calculating the ablation amount to adjust the nozzle throat diameter and inner surface shape, accurate and automatic updates of the nozzle morphology based on physical ablation results are achieved. This process not only eliminates the need for manual modification of the geometric model but also accurately reflects the actual impact of ablation on the nozzle inner wall morphology, effectively improving the consistency between the updated simulation model and the actual ablation condition. Furthermore, it strengthens the automated closed loop from simulation parameter extraction to geometric model reconstruction, providing a computational domain more closely aligned with the actual morphology for subsequent mesh remapping and boundary condition inheritance.

[0034] In some embodiments, after re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed grid, a thermal-fluid coupling simulation is run to obtain the high-current arc breaking characteristics under the current operating condition, specifically: The original mesh is automatically cleared, and a new finite element mesh is generated based on the boundaries of the flow field region and the solid region in the simulation geometry model, according to the preset mesh parameters. Extract various boundary conditions that have been set on the two-dimensional axisymmetric geometric model, including inlet pressure, outlet pressure and initial temperature, and automatically associate and assign the boundary conditions to the corresponding boundaries of the finite element mesh according to the boundary name or spatial location correspondence. Run thermal-fluid coupling simulation calculations and output the curves of arc voltage, arc conductivity and temperature distribution at the nozzle throat under the current operating conditions as a function of time, which serve as the high-current arc breaking characteristics. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset value, the calculation ends. If the deviation is greater than the preset value, the ablation constant is adjusted and the simulation calculation is performed again.

[0035] By automatically clearing the original mesh and regenerating the finite element mesh according to preset parameters based on the updated flow field and solid region boundaries, and by automatically associating and assigning boundary conditions such as inlet pressure, outlet pressure, and initial temperature from the original model to the new mesh by boundary name or spatial location, the pre-simulation processing stage after geometric update is fully automated. This eliminates the repetitive work of manually re-meshing and resetting boundary conditions, and ensures the accuracy and consistency of boundary condition transfer. On this basis, thermal-fluid coupling simulation is run and characteristic curves such as arc voltage, arc conductivity, and throat temperature distribution are output. Combined with closed-loop comparison with measured values ​​after multi-time step calculation and adaptive adjustment of ablation constant, a complete closed-loop process from model update to characteristic prediction to verification and correction is formed. This significantly shortens the simulation cycle while effectively improving the reliability and accuracy of high-current arc breaking characteristic prediction.

[0036] Example 1 This invention proposes a parameterized modeling method for nozzle size in high-current arc breaking test simulation based on finite element method. The core innovation of this method is to combine the empirical formula for nozzle throat ablation with the parameterization function of finite element software to establish a quantitative relationship between ablation amount and operating parameters (airflow velocity, arc current, and action time), thereby realizing automatic updating of nozzle throat size and automatic reconstruction of finite element model.

[0037] The method of the present invention includes the following steps: Step 1: Establish a two-dimensional geometric model for the high-current arc breaking test Based on the actual structural dimensions of the circuit breaker nozzle, a two-dimensional axisymmetric geometric model is established in CAD software. The geometric model should include key structures such as the stationary contact, moving contact, nozzle body, and throat region.

[0038] Step 2: Extract the initial dimensions of the nozzle throat. Mark the locations of key nodes in the geometric model and extract the initial throat radii r1, r2, r3, etc. These nodes will serve as reference points for subsequent parameterization updates.

[0039] Step 3: Build a finite element model and run calculations in the finite element environment. Import the geometric model into arc simulation analysis software (such as Fluent, Fluent and Maxwell combined), perform mesh generation, boundary condition setting and initial condition setting, and then run thermal-fluid coupling simulation calculation.

[0040] Step 4: Create post-processing functions In the post-processing stage, two key functions are established: Fluid velocity extraction function: used to extract the airflow velocity v at the throat wall; Current detection function: used to monitor the real-time value of arc current I(t); Step 5: Obtain operating parameters The following parameters are obtained through the post-processing function: The airflow velocity v at the throat wall; Arc current I (time-varying function); Ablation constant k (determined based on nozzle material properties); Arc duration t; Step 6: Parametric processing of critical throat dimensions Based on empirical formulas, the critical dimensions of the throat are parameterized in the finite element environment. Specifically, the throat radius rt is defined as a function of time t: rt = f(t), where f(t) is determined by the formula.

[0041] Step 7: Obtain new geometric models under different initial parameters By modifying parameterized variables (such as the initial throat radius r0, ablation constant k, etc.), new geometric models under different working conditions can be automatically generated.

[0042] Step 8: Automatic Update of Flow Solid Mesh After the geometric model is updated, the arc simulation analysis software automatically re-meshes the flow field region and the solid region, generating a finite element mesh that matches the new geometric model.

[0043] Step 9: Boundary condition settings are automatically updated. After the mesh is updated, the original boundary condition settings (such as inlet pressure, outlet pressure, initial temperature, etc.) are automatically applied to the new mesh model without the need for manual resetting.

[0044] Step 10: Run the new finite element model After completing the above updates, run the new finite element simulation calculation directly to obtain the arc breaking characteristics under this working condition.

[0045] The entire process can be iterated and looped, achieving seamless parameterization from the first test to subsequent tests.

[0046] The core formula of the technical solution is:

[0047] in: This represents the initial throat radius parameter; Indicates the radius of the nozzle throat at time t; This represents the ablation constant (related to the properties of the nozzle material). Indicates the airflow velocity at the throat wall; This represents a function of arc current as a function of time. Indicates the duration of the electric arc.

[0048] Example 2 like Figure 3 As shown, based on the same inventive concept as the above embodiments, the present invention also provides a parameterized modeling system for nozzle size in high-current arc breaking test simulation, characterized in that it includes: The geometric modeling unit is used to obtain the actual structural dimensions of the circuit breaker nozzle and to establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body and throat area based on the actual structural dimensions of the circuit breaker nozzle. The parameter extraction unit is used to mark the key node positions at the throat in the two-dimensional axisymmetric geometric model and extract the initial throat radius parameter; The simulation calculation unit is used to sequentially mesh the two-dimensional axisymmetric geometric model, set the boundary conditions and initial conditions, and run the thermal-fluid coupling simulation calculation to obtain the simulation calculation results of the current time step; The simulation parameter extraction unit is used to extract the airflow velocity, arc current and arc duration at the throat wall based on the simulation calculation results of the current time step, and to determine the ablation constant. The parametric modeling unit is used to calculate the throat ablation based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The model update unit is used to update the initial throat radius parameter according to the throat ablation amount, and to update the corresponding simulation geometric model. The updated simulation calculation unit is used to re-mesh the simulation geometric model and map the boundary conditions of the two-dimensional axisymmetric geometric model to the re-mesh. Then, it runs the thermal-fluid coupling simulation calculation to obtain the high-current arc breaking characteristics of the next time step. The judgment unit is used to compare the calculated value with the measured value after all time steps have been calculated. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

[0049] Example 3 like Figure 4 As shown, the present invention also provides an electronic device 100 for implementing a method for parametric modeling of nozzle size in a high-current arc breaking test simulation. The electronic device 100 includes a memory 101, at least one processor 102, a computer program 103 stored in the memory 101 and executable on at least one processor 102, and at least one communication bus 104.

[0050] The memory 101 can be used to store the computer program 103. The processor 102 implements the steps of the parameterized modeling method for nozzle size in high current arc breaking test simulation by running or executing the computer program stored in the memory 101 and calling the data stored in the memory 101.

[0051] The memory 101 may primarily include a program storage area and a data storage area. The program storage area may store the operating system, application programs required for at least one function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created based on the use of the electronic device 100 (such as audio data), etc. In addition, the memory 101 may include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0052] At least one processor 102 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Processor 102 may be a microprocessor or any conventional processor. Processor 102 is the control center of electronic device 100, connecting various parts of electronic device 100 via various interfaces and lines.

[0053] The memory 101 in the electronic device 100 stores multiple instructions to implement a parameterized modeling method for nozzle size in a high-current arc breaking test simulation. The processor 102 can execute multiple instructions to achieve the following: Obtain the actual structural dimensions of the circuit breaker nozzle, and establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body and throat region based on the actual structural dimensions of the circuit breaker nozzle; In a two-dimensional axisymmetric geometric model, the key node positions at the throat are marked, and the initial throat radius parameter is extracted; The two-dimensional axisymmetric geometric model is meshed, boundary conditions and initial conditions are set sequentially, and thermal-fluid coupling simulation is run to obtain the simulation results at the current time step; Based on the simulation results of the current time step, the airflow velocity, arc current and arc duration at the throat wall are extracted, and the ablation constant is determined. The throat ablation amount is calculated based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The initial throat radius parameter is updated based on the throat ablation amount, and the corresponding simulation geometric model is obtained. After re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed mesh, a thermal-fluid coupling simulation was run to obtain the high-current arc breaking characteristics of the next time step. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

[0054] Example 4 If the modules / units integrated in the electronic device 100 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, and read-only memory (ROM).

[0055] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0056] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0057] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0058] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0059] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for parametric modeling of nozzle dimensions in a high-current arc breaking test simulation, characterized in that, include: Obtain the actual structural dimensions of the circuit breaker nozzle, and establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body, and throat region based on the actual structural dimensions of the circuit breaker nozzle; In a two-dimensional axisymmetric geometric model, the key node positions at the throat are marked, and the initial throat radius parameters are extracted. The two-dimensional axisymmetric geometric model is meshed, boundary conditions and initial conditions are set sequentially, and thermal-fluid coupling simulation is run to obtain the simulation results at the current time step; Based on the simulation results of the current time step, the airflow velocity, arc current and arc duration at the throat wall are extracted, and the ablation constant is determined. The throat ablation amount is calculated based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The initial throat radius parameter is updated based on the throat ablation amount, and the corresponding simulation geometric model is obtained. After re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed mesh, a thermal-fluid coupling simulation was run to obtain the high-current arc breaking characteristics of the next time step. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

2. The method for parameterized modeling of nozzle dimensions in a high-current arc breaking test simulation according to claim 1, characterized in that, The parameterized model for the nozzle throat dimensions is specifically as follows: In the formula, This represents the initial throat radius parameter; Indicates the radius of the nozzle throat at time t; Indicates the ablation constant; Indicates the airflow velocity at the throat wall; This represents a function of arc current as a function of time. Indicates the duration of the electric arc.

3. The method for parameterized modeling of nozzle dimensions in a high-current arc breaking test simulation according to claim 1, characterized in that, Based on the actual structural dimensions of the circuit breaker nozzle, a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body, and throat region is established in CAD software. The key node positions at the throat are marked in the two-dimensional axisymmetric geometric model, specifically: the starting point of the upstream contraction section of the nozzle, the intersection of the upstream contraction section and the straight section of the throat, the intersection of the straight section of the throat and the downstream expansion section, the ending point of the downstream expansion section of the nozzle, and the radial coordinates of the intersection of the upstream contraction section and the straight section of the throat, and the intersection of the straight section of the throat and the downstream expansion section, which serve as the initial throat radius parameters.

4. The method for parameterized modeling of nozzle dimensions in a high-current arc breaking test simulation according to claim 1, characterized in that, The two-dimensional axisymmetric geometric model was imported into the electric arc simulation analysis software. The two-dimensional axisymmetric geometric model was then meshed, and the boundary conditions and initial conditions were set in sequence. The thermal-fluid coupling simulation calculation was then run to obtain the initial simulation calculation results.

5. The method for parameterized modeling of nozzle dimensions in a high-current arc breaking test simulation according to claim 1, characterized in that, Based on the simulation results of the current time step, the airflow velocity, arc current, and arc duration at the throat wall are extracted. Specifically, the gas velocity, arc current, and arc duration at the throat are exported to an ASCII file. The gas velocity at the throat is the average gas velocity obtained by integrating the gas velocity of the grid cells on the throat surface and dividing it by the number of grid cells, as shown in the following formula: In the formula, n This represents the number of grid cells for the straight segment of the throat. This represents the average gas flow rate; The gas velocity of the grid cells on the throat surface; The arc current is the current instantaneous value of the current boundary conditions in the simulation calculation. The arc duration is the current fluid time. In the formula, It is the arc current; This represents the peak current.

6. The method for parameterized modeling of nozzle dimensions in a high-current arc breaking test simulation according to claim 5, characterized in that, The CAD software was used to read the ASCII file and extract the gas velocity, arc current and arc duration. The throat ablation was calculated based on the gas velocity, arc current and arc duration. The nozzle throat diameter was adjusted according to the throat ablation and the nozzle inner surface shape was updated to obtain the corresponding simulation geometric model.

7. The method for parameterized modeling of nozzle dimensions in a high-current arc breaking test simulation according to claim 1, characterized in that, After re-meshing the simulation geometric model and mapping the boundary conditions of the two-dimensional axisymmetric geometric model to the re-meshed grid, a thermal-fluid coupled simulation calculation is run to obtain the high-current arc breaking characteristics under the current operating conditions, specifically: The original mesh is automatically cleared, and a new finite element mesh is generated based on the boundaries of the flow field region and the solid region in the simulation geometry model, according to the preset mesh parameters. Extract various boundary conditions that have been set on the two-dimensional axisymmetric geometric model, including inlet pressure, outlet pressure and initial temperature, and automatically associate and assign the boundary conditions to the corresponding boundaries of the finite element mesh according to the boundary name or spatial location correspondence. Run thermal-fluid coupling simulation calculations and output the curves of arc voltage, arc conductivity and temperature distribution at the nozzle throat under the current operating conditions as a function of time, which serve as the high-current arc breaking characteristics. After all time steps are calculated, the calculated values ​​are compared with the measured values. If the deviation is not greater than the preset value, the calculation ends. If the deviation is greater than the preset value, the ablation constant is adjusted and the simulation calculation is performed again.

8. A parameterized modeling system for nozzle dimensions in a high-current arc breaking test simulation, characterized in that, include: The geometric modeling unit is used to obtain the actual structural dimensions of the circuit breaker nozzle and to establish a two-dimensional axisymmetric geometric model including the stationary contact, moving contact, nozzle body and throat area based on the actual structural dimensions of the circuit breaker nozzle. The parameter extraction unit is used to mark the key node positions at the throat in the two-dimensional axisymmetric geometric model and extract the initial throat radius parameter; The simulation calculation unit is used to sequentially mesh the two-dimensional axisymmetric geometric model, set the boundary conditions and initial conditions, and run the thermal-fluid coupling simulation calculation to obtain the simulation calculation results of the current time step; The simulation parameter extraction unit is used to extract the airflow velocity, arc current and arc duration at the throat wall based on the simulation calculation results of the current time step, and to determine the ablation constant. The parametric modeling unit is used to calculate the throat ablation based on the initial throat radius parameters, airflow velocity at the throat wall, arc current, ablation constant, and arc duration. The model update unit is used to update the initial throat radius parameter according to the throat ablation amount, and to update the corresponding simulation geometric model. The updated simulation calculation unit is used to re-mesh the simulation geometric model and map the boundary conditions of the two-dimensional axisymmetric geometric model to the re-mesh. Then, it runs the thermal-fluid coupling simulation calculation to obtain the high-current arc breaking characteristics of the next time step. The judgment unit is used to compare the calculated value with the measured value after all time steps have been calculated. If the deviation is not greater than the preset threshold, the calculation ends. If the deviation is greater than the preset threshold, the ablation constant is adjusted and the simulation calculation is performed again.

9. An electronic device, characterized in that, It includes a processor and a memory, the processor being used to execute a computer program stored in the memory to implement a parameterized modeling method for nozzle size in a high-current arc breaking test simulation as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one instruction, which, when executed by a processor, implements a parameterized modeling method for nozzle size in a high-current arc breaking test simulation as described in any one of claims 1 to 7.

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