Arc simulation method of HSS under clean air insulation and related device

Abstract

The invention discloses an electric arc simulation method of an HSS under clean air insulation and a related device, and the method comprises the steps: taking clean air as an insulating medium and an arc extinguishing medium, and building a two-dimensional axisymmetric geometric model of a DC high-speed parallel switch arc extinguishing chamber; calculating physical property parameters of the electric arc in the clean air based on the geometric model, wherein the physical property parameters comprise thermodynamic properties and transportation parameters; constructing a magnetohydrodynamic model according to a Navier-Stokes equation and the physical property parameters, wherein the magnetohydrodynamic model comprises a fluid equation and an electromagnetic field equation; based on a preset k-epsilon turbulence model, the magnetohydrodynamic model is solved through Fluent, and arc airflow field parameters are obtained; and performing arc simulation operation according to the arc airflow field parameters to obtain a target clean air arc. The technical problem that existing HSS application is not environment-friendly due to the lack of research on plasma characteristics and arc extinguishing capability of clean air HSS arcs in the prior art can be solved.

Description

Technical Field

[0001] This application relates to the field of power transmission systems, and in particular to an arc simulation method and related apparatus for HSS under clean air insulation. Background Technology

[0002] High-speed DC switches (HSS), in conjunction with converter valves, can interrupt small DC currents, playing a crucial role in isolating faulty DC lines and improving the availability of multi-terminal DC transmission systems. Hybrid HSSs use a combination of power electronic switches and fast mechanical switches for small DC current interruption, offering high interruption speed but also high losses and poor current withstand capability. The HSSs used in UHV multi-terminal DC transmission projects both domestically and internationally are all SF6 switches. Since these high-speed switches all use SF6 as the arc-extinguishing medium, and given the trend towards environmentally friendly power equipment development, SF6, with a greenhouse effect 23,500 times that of CO2, faces strict restrictions, necessitating the search for environmentally friendly alternatives.

[0003] Clean air is easy to prepare and has a significantly lower greenhouse effect than SF6, making it a strong contender to replace SF6. However, there are currently no comprehensive research methods for the plasma characteristics and arc-extinguishing capabilities of clean air HSS arcs, and no stable and reliable technical solutions can support the application requirements of practical scenarios, resulting in the environmentally unfriendly nature of actual HSS applications. Summary of the Invention

[0004] This application provides a method and related apparatus for simulating electric arcs in clean air-insulated HSS, which addresses the technical problem that the lack of research on the plasma characteristics and arc extinguishing capabilities of HSS electric arcs in existing technologies leads to the environmentally unfriendly nature of current HSS applications.

[0005] In view of this, the first aspect of this application provides an arc simulation method for HSS under clean air insulation, comprising:

[0006] A two-dimensional axisymmetric geometric model of the arc-extinguishing chamber of a DC high-speed parallel switch is established using clean air as the insulating and arc-extinguishing medium.

[0007] The physical properties of the electric arc under clean air are calculated based on the geometric model, including thermodynamic properties and transport parameters.

[0008] A magnetohydrodynamic model is constructed based on the Navier-Stokes equations and the aforementioned physical parameters. The magnetohydrodynamic model includes fluid equations and electromagnetic field equations.

[0009] Based on the preset k-ε turbulence model, the magnetohydrodynamic model is solved using Fluent to obtain the electric arc airflow field parameters;

[0010] An electric arc simulation operation is performed based on the electric arc airflow field parameters to obtain the target clean air electric arc.

[0011] Preferably, the calculation of the physical properties of the electric arc under clean air based on the geometric model includes thermodynamic properties and transport parameters, including:

[0012] The geometric model is used to simulate arc plasma under nonlocal thermodynamic equilibrium.

[0013] Based on Gibbs' principle of minimum free energy, the plasma composition of the arc plasma under different pressures and temperatures was obtained, and the partition functions and particle composition of various particles in the arc plasma were calculated.

[0014] Based on thermodynamic theory, the mass density, enthalpy, and specific heat capacity at constant pressure of the arc plasma are calculated according to the partition function and the particle composition to obtain the thermodynamic properties.

[0015] The electrical conductivity, thermal conductivity, and viscosity coefficient of the arc plasma were calculated using the Chapman-Enskog method to obtain the transport parameters.

[0016] Preferably, the step of obtaining the arc flow field parameters by solving the magnetohydrodynamic model using Fluent based on a preset k-ε turbulence model further includes:

[0017] A pre-defined k-ε turbulence model is constructed based on the turbulent kinetic energy equation and the turbulent dissipation rate equation. The turbulent kinetic energy equation is used to describe the turbulent kinetic energy, and the turbulent dissipation rate equation is used to describe the turbulent dissipation rate.

[0018] Preferably, the geometric model includes a moving contact, a stationary contact, a nozzle, and a compressor cylinder.

[0019] The second aspect of this application provides an arc simulation device for HSS under clean air insulation, comprising:

[0020] The first modeling unit is used to establish a two-dimensional axisymmetric geometric model of the arc-extinguishing chamber of a DC high-speed parallel switch, using clean air as the insulating and arc-extinguishing medium.

[0021] The parameter calculation unit is used to calculate the physical property parameters of the electric arc under clean air based on the geometric model. The physical property parameters include thermodynamic properties and transport parameters.

[0022] The second modeling unit is used to construct a magnetohydrodynamic model based on the Navier-Stokes equations and the physical property parameters. The magnetohydrodynamic model includes fluid equations and electromagnetic field equations.

[0023] The model solving unit is used to solve the magnetohydrodynamic model based on the preset k-ε turbulence model using Fluent to obtain the electric arc airflow field parameters;

[0024] The arc simulation unit is used to perform arc simulation operations based on the arc airflow field parameters to obtain the target clean air arc.

[0025] Preferably, the parameter calculation unit is specifically used for:

[0026] The geometric model is used to simulate arc plasma under nonlocal thermodynamic equilibrium.

[0027] Based on Gibbs' principle of minimum free energy, the plasma composition of the arc plasma under different pressures and temperatures was obtained, and the partition functions and particle composition of various particles in the arc plasma were calculated.

[0028] Based on thermodynamic theory, the mass density, enthalpy, and specific heat capacity at constant pressure of the arc plasma are calculated according to the partition function and the particle composition to obtain the thermodynamic properties.

[0029] The electrical conductivity, thermal conductivity, and viscosity coefficient of the arc plasma were calculated using the Chapman-Enskog method to obtain the transport parameters.

[0030] Preferably, it further includes:

[0031] The third modeling unit is used to construct a preset k-ε turbulence model based on the turbulent kinetic energy equation and the turbulent dissipation rate equation. The turbulent kinetic energy equation is used to describe turbulent kinetic energy, and the turbulent dissipation rate equation is used to describe turbulent dissipation rate.

[0032] Preferably, the geometric model includes a moving contact structure, a stationary contact structure, a nozzle structure, and a compressor cylinder structure.

[0033] A third aspect of this application provides an arc simulation device for HSS under clean air insulation, the device including a processor and a memory;

[0034] The memory is used to store program code and transmit the program code to the processor;

[0035] The processor is used to execute the arc simulation method of HSS under clean air insulation as described in the first aspect according to the instructions in the program code.

[0036] The fourth aspect of this application provides a computer-readable storage medium for storing program code for executing the arc simulation method for HSS under clean air insulation as described in the first aspect.

[0037] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0038] This application provides a method for simulating the electric arc of a high-speed DC parallel switch (HSS) under clean air insulation, comprising: establishing a two-dimensional axisymmetric geometric model of the arc-extinguishing chamber of a DC high-speed parallel switch using clean air as the insulating and arc-extinguishing medium; calculating the physical property parameters of the electric arc under clean air based on the geometric model, including thermodynamic properties and transport parameters; constructing a magnetohydrodynamic (MHD) model based on the Navier-Stokes equations and the physical property parameters, including fluid equations and electromagnetic field equations; obtaining the electric arc airflow field parameters by solving the MHD model using Fluent based on a preset k-ε turbulence model; and performing an electric arc simulation operation based on the electric arc airflow field parameters to obtain the target clean air electric arc.

[0039] The arc simulation method for HSS (High-Speed ​​Solid) under clean air insulation provided in this application offers a stable and reliable simulation scheme for low-current arcs in clean air, enabling practical applications of HSS. This scheme provides accurate parameters for simulating HSS arcs through modeling and parameter calculation. Based on a preset k-ε turbulence model and the Fluent method for solving the model, the accuracy and reliability of the solved arc flow field parameters are ensured. Therefore, the target clean air arc simulated based on these parameters can replace SF6 to meet the practical application requirements of HSS. Thus, this application addresses the technical problem of the lack of research on the plasma characteristics and arc-extinguishing capabilities of clean air HSS arcs in existing technologies, leading to the environmentally unfriendly nature of current HSS applications. Attached Figure Description

[0040] Figure 1 A flowchart illustrating an arc simulation method for HSS under clean air insulation provided in this application embodiment;

[0041] Figure 2 This is a schematic diagram of the structure of an arc simulation device for HSS under clean air insulation provided in an embodiment of this application. Detailed Implementation

[0042] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0043] For easier understanding, please refer to Figure 1 An embodiment of an arc simulation method for HSS under clean air insulation provided in this application includes:

[0044] Step 101: Using clean air as the insulating and arc-extinguishing medium, establish a two-dimensional axisymmetric geometric model of the arc-extinguishing chamber of a DC high-speed parallel switch.

[0045] Furthermore, the geometric model includes a moving contact structure, a stationary contact structure, a nozzle structure, and a compressor cylinder structure.

[0046] The geometric modeling in this embodiment involves modeling the actual hardware equipment necessary for generating a DC high-speed parallel switch arc, simplifying the scenario into a two-dimensional axisymmetric model. For example, a rectangular area is used to represent the arc fluid domain, and the electrode spacing is adjustable, such as a 100mm×100mm square area. The electrode material can be copper, and it needs to be clearly distinguished from the insulation layer. The clean air domain needs to cover the arc extension area.

[0047] Step 102: Calculate the physical properties of the electric arc under clean air based on the geometric model. The physical properties include thermodynamic properties and transport parameters.

[0048] It should be noted that this embodiment uses a constructed geometric model to simulate an electric arc under clean air, and then uses different algorithms to calculate different physical property parameters of the electric arc particles, including but not limited to thermodynamic properties and transport parameters.

[0049] Thermodynamic properties can be calculated based on the Gibbs principle of minimum free energy and thermodynamic theory. The Gibbs principle of minimum free energy is used to decompose the particle components, and then the thermodynamic properties of the mixture are integrated based on thermodynamic theory. Alternatively, chemical kinetic equations can be used to decompose the particle components through dissociation, electrical reactions, and recombination reactions, followed by corrective calculations of the mixture's thermodynamic properties. Alternatively, physical parameters can be predicted using trained machine learning models. These methods can also be improved or combined for calculating thermodynamic properties; this is merely an example and not a limitation.

[0050] Transport parameters can be obtained directly through multi-stage calculations using the Chapman-Enskog method. Alternatively, the viscosity and thermal conductivity of a single component can be calculated first using the Chapman-Enskog method, followed by the Wilke equation to calculate the viscosity coefficient of the mixture. Then, the Eucken correction formula and the Saha equation can be used to calculate the thermal and electrical conductivity of the mixture. This process can also incorporate a temperature correction factor into the modified Wilke equation to ensure the accuracy of the viscosity coefficient calculation. Thermal conductivity can also be calculated by separating the relationship between electronic thermal conductivity and heavy particle thermal conductivity. Furthermore, a more reliable electrical conductivity can be calculated using the collision frequency correction formula and the Drude model. In addition, transport parameters can be predicted using a trained neural network model, and then the predicted values ​​can be weighted and fused with the transport parameters calculated using the Chapman-Enskog method to obtain the target transport parameters. In this process, a quantum mechanical correction term can be introduced in the high-temperature range to ensure that the calculated electrical conductivity error is less than 5%.

[0051] As a further embodiment, step 102 includes:

[0052] Simulation of arc plasma under nonlocal thermodynamic equilibrium based on geometric model;

[0053] Based on Gibbs' principle of minimum free energy, the plasma composition of arc plasma under different pressures and temperatures was obtained, and the partition functions and particle composition of various particles in the arc plasma were calculated.

[0054] Based on thermodynamic theory, the mass density, enthalpy, and specific heat capacity at constant pressure of the arc plasma are calculated according to the partition function and particle composition, thus obtaining its thermodynamic properties.

[0055] The electrical conductivity, thermal conductivity, and viscosity of the arc plasma were calculated using the Chapman-Enskog method to obtain transport parameters.

[0056] It should be noted that the temperature, airflow velocity, and gas pressure of the clean air arc are closely related to the evolution of microscopic plasma physical parameters and are crucial parameters for determining whether the arc can be extinguished, directly affecting the DC small current interruption result. Therefore, the arc model of the DC HSS requires solving for the arc temperature, airflow velocity, and gas pressure to provide necessary data for further determination of whether the arc can be extinguished.

[0057] Therefore, this embodiment requires the calculation of various physical property parameters based on the geometric model before modeling. These physical property parameters can be divided into thermodynamic properties and transport parameters. Thermodynamic properties include mass density, enthalpy, and specific heat capacity at constant pressure, while transport parameters include electrical conductivity, thermal conductivity, and viscosity coefficient. The area within the geometric model excluding the moving structure, stationary contact structure, nozzle structure, and compressor structure is the clean air domain. In this air domain portion of the geometric model, the arc plasma under non-local thermodynamic equilibrium can be simulated; then, parameter calculations are performed.

[0058] Gibbs free energy characterizes the maximum energy a system can perform non-volume work on under isothermal and isobaric conditions (often assumed to be constant pressure, such as 0.1 MPa, in arc calculations). The principle of minimum Gibbs free energy essentially states that in a closed system under isothermal and isobaric conditions, neglecting non-volume work, spontaneous processes always proceed in the direction of decreasing Gibbs free energy. When the system reaches equilibrium, the Gibbs free energy reaches its minimum value. For multi-component mixed systems, such as clean air and its dissociation / ionization products... , The equilibrium state is determined by the minimum total Gibbs free energy of the system, where the mole fraction of each component no longer changes, i.e., chemical equilibrium is reached. In this embodiment, the most stable and reliable dissociation results of each particle component of the arc plasma are obtained when the Gibbs free energy is at its minimum.

[0059] The Chapman-Enskog method, or CE expansion for short, is an asymptotic expansion method for deriving macroscopic fluid dynamics equations from the Boltzmann equations. This method introduces the Knudsen number or Knudsen number as expansion factors, expanding the distribution function, derivatives, and physical quantities at different orders, ultimately deriving macroscopic equations such as the Euler equations and the Navier-Stokes equations. Its core ideas include multi-scale expansion and higher-order moment approximation. Multi-scale expansion expands the distribution function according to the dimensionless Knudsen number, which characterizes the rarefaction of the gas, approximating the macroscopic equations step by step. Higher-order moment approximation closes the equation system by neglecting higher-order moments, such as the momentum-fluidity tensor and heat flux, thus obtaining solvable macroscopic equations. This embodiment uses the Chapman-Enskog method to calculate transport parameters, specifically using the third-order approximation to calculate electronic conductivity and translational thermal conductivity, and the first-order approximation to calculate the viscosity coefficient.

[0060] Step 103: Construct a magnetohydrodynamic model based on the Navier-Stokes equations and physical property parameters. The magnetohydrodynamic model includes fluid equations and electromagnetic field equations.

[0061] This embodiment uses the Navier-Stokes equations to describe the state of clean-air arc plasma, assuming that electrons and heavy particles are in local thermodynamic equilibrium and follow a Maxwell-Boltzmann distribution. The fluid equations describe the conservation laws governing fluid velocity and energy, and are coupled to the electromagnetic field equations through current density. The Navier-Stokes equations in this embodiment are expressed as follows:

[0062]

[0063]

[0064]

[0065]

[0066] The first equation above is the plasma density conservation equation. The second and third equations are the plasma radial and axial momentum conservation equations, respectively. The terms on the right-hand side are source terms, representing the contributions of internal ion pressure and electron pressure, the Ampere force under the magnetic field, and ionic viscous tension. The fourth equation is the plasma energy conservation equation, with the terms on the right-hand side considering energy conversions from heat conduction, electron collisions, and internal fluid friction. From the charge neutrality condition, we can obtain:

[0067]

[0068] The constraint relationship between electron velocity and ion velocity is expressed as:

[0069]

[0070]

[0071]

[0072] The energy conservation equation for electrons takes into account energy transfer processes during collisions, Joule heating, and thermodynamic terms:

[0073]

[0074] The electromagnetic field equations are:

[0075]

[0076] Where r represents radial direction, z represents axial direction, and n i n represents the ion number density. e Represents electron number density, m i It is the ionic mass, m e It is electronic quality, T i It is the ion temperature, Te It is the electron temperature, p i It is ion pressure, p e It is electron pressure, u is ion velocity, u r It is the radial ion velocity, u z v is the axial ion velocity, v is the electron velocity, v r It is the radial electron velocity, v z It is the axial electron velocity, v θ j is the circumferential electron velocity, j is the current density, j r It is the radial current density, j z It is the axial current density, j θ It is the circumferential current density, B z It is the axial magnetic induction intensity, B θ It is the circumferential magnetic induction intensity, λ i It is the ionic thermal conductivity, v ei It is the collision frequency between electrons and ions. It is the ionic viscous stress tensor, g T σ is a coefficient, typically taken as 3 / 2 for fully ionized plasma, e is the electron charge, σ is the conductivity, μ0 is the vacuum permeability, and β is the magnetic permeability. e φ is the electron Hall coefficient, φ is the electric potential, k is the Boltzmann constant, A is the magnetic vector potential, and c is the speed of light in vacuum.

[0077] Step 104: Based on the preset k-ε turbulence model, solve the magnetohydrodynamic model using Fluent to obtain the electric arc airflow field parameters.

[0078] Furthermore, step 104, preceding the following, also includes:

[0079] A pre-defined k-ε turbulence model is constructed based on the turbulent kinetic energy equation and the turbulent dissipation rate equation. The turbulent kinetic energy equation is used to describe the turbulent kinetic energy, and the turbulent dissipation rate equation is used to describe the turbulent dissipation rate.

[0080] Step 105: Perform an electric arc simulation operation based on the electric arc airflow field parameters to obtain the target clean air electric arc.

[0081] The preset k-ε turbulence model is used to describe gas turbulence effects, specifically expressed as follows:

[0082]

[0083] Where n is the gas density, κ is the turbulent kinetic energy, ε is the turbulent energy dissipation rate, and μ is the laminar viscosity. t Where is the turbulent viscosity, u is the ion velocity, C1=1.44, C2=1.92, C μ =0.09, σ κ =1.00, σ ε =1.30.

[0084] Fluent can be used to simulate complex linear physical phenomena such as fluid flow, heat transfer, and chemical reactions. The algorithm defaults to a pressure-based segregated solver, while a density-based solver can be switched for more complex problems. The algorithm's convergence criterion is that residual convergence is only a necessary condition; stability must be assessed in conjunction with monitoring points, such as inlet pressure drop and maximum fluid temperature. The obtained arc flow field parameters include, but are not limited to, the temperature, pressure, and velocity distribution of the arc flow field. Based on these parameters, effective arc simulation can be performed, providing a design basis for the development of high-speed parallel clean air switches.

[0085] The arc simulation method for HSS under clean air insulation provided in this application provides a stable and reliable clean air low-current arc simulation scheme for practical applications of HSS. This scheme provides accurate parameters for simulating HSS arcs through modeling and parameter calculation. Based on a preset k-ε turbulence model and Fluent's solution method, it ensures the accuracy and reliability of the solved arc flow field parameters. Therefore, the target clean air arc simulated based on these parameters can replace SF6 to meet the practical application requirements of HSS. Thus, this application solves the technical problem of the lack of research on the plasma characteristics and arc-extinguishing capabilities of clean air HSS arcs in the prior art, leading to the environmentally unfriendly nature of existing HSS applications.

[0086] For easier understanding, please refer to Figure 2 This application provides an embodiment of an arc simulation device for HSS under clean air insulation, comprising:

[0087] The first modeling unit 201 is used to establish a two-dimensional axisymmetric geometric model of the arc-extinguishing chamber of a DC high-speed parallel switch, using clean air as the insulating and arc-extinguishing medium.

[0088] The parameter calculation unit 202 is used to calculate the physical property parameters of the electric arc under clean air based on the geometric model. The physical property parameters include thermodynamic properties and transport parameters.

[0089] The second modeling unit 203 is used to construct a magnetohydrodynamic model based on the Navier-Stokes equations and physical property parameters. The magnetohydrodynamic model includes fluid equations and electromagnetic field equations.

[0090] Model solver 204 is used to solve the magnetohydrodynamic model based on the preset k-ε turbulence model and obtain the electric arc airflow field parameters through Fluent.

[0091] The arc simulation unit 205 is used to perform arc simulation operations based on the arc airflow field parameters to obtain the target clean air arc.

[0092] Furthermore, the parameter calculation unit 202 is specifically used for:

[0093] Simulation of arc plasma under nonlocal thermodynamic equilibrium based on geometric model;

[0094] Based on Gibbs' principle of minimum free energy, the plasma composition of arc plasma under different pressures and temperatures was obtained, and the partition functions and particle composition of various particles in the arc plasma were calculated.

[0095] Based on thermodynamic theory, the mass density, enthalpy, and specific heat capacity at constant pressure of the arc plasma are calculated according to the partition function and particle composition, thus obtaining its thermodynamic properties.

[0096] The electrical conductivity, thermal conductivity, and viscosity of the arc plasma were calculated using the Chapman-Enskog method to obtain transport parameters.

[0097] Furthermore, it also includes:

[0098] The third modeling unit 206 is used to construct a preset k-ε turbulence model based on the turbulent kinetic energy equation and the turbulent dissipation rate equation. The turbulent kinetic energy equation is used to describe turbulent kinetic energy, and the turbulent dissipation rate equation is used to describe turbulent dissipation rate.

[0099] Furthermore, the geometric model includes a moving contact structure, a stationary contact structure, a nozzle structure, and a compressor cylinder structure.

[0100] This application also provides an arc simulation device for HSS under clean air insulation, the device including a processor and a memory;

[0101] The memory is used to store program code and transfer the program code to the processor;

[0102] The processor is used to execute the arc simulation method of HSS under clean air insulation in the above method embodiment according to the instructions in the program code.

[0103] This application also provides a computer-readable storage medium for storing program code for executing the arc simulation method of HSS under clean air insulation in the above method embodiments.

[0104] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0105] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0106] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0107] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of this application through a computer device (which may be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0108] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method of arc simulation for clean air insulated lower HSS, characterized by, The application relates to a method for simulating an arc in clean air. The method comprises the following steps: a two-dimensional axisymmetric geometric model of a DC high-speed parallel switch arc chamber is established by taking clean air as an insulating medium and arc extinguishing medium; physical parameters of an arc in clean air are calculated based on the geometric model, wherein the physical parameters comprise thermodynamic properties and transport parameters; a magnetohydrodynamic model is constructed according to Navier-Stokes equations and the physical parameters, wherein the magnetohydrodynamic model comprises fluid equations and electromagnetic field equations; the magnetohydrodynamic model is solved by Fluent based on a preset k-epsilon turbulent flow model, so that arc gas flow field parameters are obtained; 2. The arc emulation method for clean air insulated lower HSS of claim 1, wherein, an arc simulation operation is performed according to the arc gas flow field parameters, so that a target clean air arc is obtained. The method for calculating the physical parameters of the arc in clean air based on the geometric model comprises the following steps: arc plasma in a non-local thermodynamic equilibrium state is simulated based on the geometric model; plasma components of the arc plasma under different pressures and different temperatures are obtained according to the Gibbs free energy minimum principle, and partition functions and particle components of various particles in the arc plasma are obtained; mass density, enthalpy and constant-pressure specific heat capacity of the arc plasma are calculated based on thermodynamic theory according to the partition functions and the particle components, so that the thermodynamic properties are obtained; 3. The method of arcing simulation of clean air insulated lower HSS of claim 1, wherein, electric conductivity, thermal conductivity and viscosity coefficient of the arc plasma are calculated by using the Chapman-Enskog method, so that the transport parameters are obtained. The method for solving the magnetohydrodynamic model by Fluent based on the preset k-epsilon turbulent flow model to obtain the arc gas flow field parameters further comprises the following steps:

4. The arc simulation method for clean air insulated lower HSS of claim 1, wherein, a preset k-epsilon turbulent flow model is constructed according to a turbulent energy equation and a turbulent dissipation rate equation, wherein the turbulent energy equation is used for describing turbulent energy, and the turbulent dissipation rate equation is used for describing turbulent dissipation rate.

5. An arc simulation device for clean air insulated down HSS, characterized by, The geometric model comprises a moving contact structure, a static contact structure, a nozzle structure and a gas cylinder structure. The application relates to a method for simulating an arc in clean air. The method comprises the following steps: a two-dimensional axisymmetric geometric model of a DC high-speed parallel switch arc chamber is established by taking clean air as an insulating medium and arc extinguishing medium; physical parameters of an arc in clean air are calculated based on the geometric model, wherein the physical parameters comprise thermodynamic properties and transport parameters; a magnetohydrodynamic model is constructed according to Navier-Stokes equations and the physical parameters, wherein the magnetohydrodynamic model comprises fluid equations and electromagnetic field equations; 6. The arc simulation device of clean air insulated lower HSS of claim 5, wherein, the magnetohydrodynamic model is solved by Fluent based on a preset k-epsilon turbulent flow model, so that arc gas flow field parameters are obtained; an arc simulation operation is performed according to the arc gas flow field parameters, so that a target clean air arc is obtained. The method for calculating the physical parameters of the arc in clean air based on the geometric model comprises the following steps: arc plasma in a non-local thermodynamic equilibrium state is simulated based on the geometric model; plasma components of the arc plasma under different pressures and different temperatures are obtained according to the Gibbs free energy minimum principle, and partition functions and particle components of various particles in the arc plasma are obtained; mass density, enthalpy and constant-pressure specific heat capacity of the arc plasma are calculated based on thermodynamic theory according to the partition functions and the particle components, so that the thermodynamic properties are obtained; electric conductivity, thermal conductivity and viscosity coefficient of the arc plasma are calculated by using the Chapman-Enskog method, so that the transport parameters are obtained. Based on the thermodynamic theory, the mass density, enthalpy and constant-pressure specific heat capacity of the arc plasma are calculated according to the partition function and the particle composition, so as to obtain the thermodynamic properties; The conductivity, thermal conductivity and viscosity coefficient of the arc plasma are calculated by using the Chapman-Enskog method, so as to obtain the transport parameters.

7. The arc simulation device of clean air insulated lower HSS of claim 5, wherein, Further comprising: A third modeling unit is configured to construct a preset k-ε turbulent flow model according to a turbulent energy equation and a turbulent dissipation rate equation, the turbulent energy equation being used to describe turbulent energy, and the turbulent dissipation rate equation being used to describe turbulent dissipation rate.

8. The arc simulation device of clean air insulated lower HSS of claim 5, wherein, The geometric model comprises a movable contact structure, a static contact structure, a nozzle structure and a compression cylinder structure.

9. An arc simulation apparatus for clean air insulated down HSS, characterized by, The device comprises a processor and a memory; The memory is configured to store program code and transmit the program code to the processor; The processor is configured to execute the arc simulation method of the clean air insulated HSS according to instructions in the program code.

10. A computer-readable storage medium, characterized in that, The computer readable storage medium is configured to store program code, and the program code is configured to execute the arc simulation method of the clean air insulated HSS.

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