Simulation method and system for partial discharge and near-field electromagnetic radiation of power equipment

Abstract

The invention discloses a simulation method for partial discharge and near-field electromagnetic radiation of power equipment, which comprises the following steps of: simulating a gas discharge process of partial discharge of the power equipment, and acquiring particle state distribution at each moment in gas discharge time based on a model of each particle in the gas discharge; obtaining electric field distribution under each time step length based on the particle state distribution; based on a plurality of excitation sources arranged on a gas discharge path and the electric field distribution, obtaining electric field time sequence change at each excitation source; the near-field electromagnetic radiation caused by gas discharge is simulated, the transient electric field of each excitation source at each simulation moment is used as the input of near-field electromagnetic radiation simulation, and the electromagnetic field change in a near-field electromagnetic radiation simulation area is acquired.

Description

Technical Field

[0001] The present invention relates to a simulation method and system, and in particular to a simulation method and system for partial discharge. Background Art

[0002] Partial discharge (PD) is the main cause of insulation failure in electrical equipment. Accurate positioning of PD can provide important information for condition monitoring and maintenance of electrical equipment.

[0003] When the discharge process occurs, physical parameters such as ultrasound, visible light, high-frequency current and electromagnetic waves are generated. The detection of these physical parameters is an important basis for judging whether the discharge has occurred. Among them, electromagnetic wave signals are widely used in the detection of discharge due to their long propagation distance and high anti-interference characteristics. The generation of electromagnetic waves is mainly because, during the discharge process, the neutral molecules in the air are ionized, generating a large number of charged particles, which move at high speed under the action of an external electric field, thereby exciting electromagnetic fluctuations in space.

[0004] Therefore, the simulation of partial discharge electromagnetic signals can be used to study partial discharge. The changes in the state of charged particles during partial discharge and the development of streamer discharge have an important impact on the electromagnetic radiation process. However, there is currently a lack of solutions for simulating electromagnetic signals of partial discharge. Summary of the invention

[0005] One of the purposes of the present invention is to provide a simulation method for local discharge and near-field electromagnetic radiation of power equipment. The method simulates the gas discharge in the local discharge process to obtain the changes in the state of charged particles and the development process of streamer discharge, as well as its influence on the electromagnetic radiation process. Thus, a joint model of the microscopic process of gas discharge and the macroscopic electromagnetic radiation process is established, thereby more intuitively reflecting the relationship between the two, which is of great significance to the status assessment of power equipment.

[0006] According to the above invention purpose, the present invention proposes a simulation method for partial discharge and near-field electromagnetic radiation of power equipment, which comprises the steps of:

[0007] The gas discharge process of partial discharge of power equipment is simulated, and the particle state distribution at each moment in the gas discharge time is obtained based on the model of each particle in the gas discharge;

[0008] Obtaining the electric field distribution at each time step based on the particle state distribution;

[0009] Based on a plurality of excitation sources arranged on the gas discharge path and the electric field distribution, obtaining a time-series change of the electric field at each excitation source;

[0010] The near-field electromagnetic radiation caused by gas discharge is simulated, and the transient electric field of each excitation source at each simulation moment is used as the input of the near-field electromagnetic radiation simulation to obtain the electromagnetic field changes in the near-field electromagnetic radiation simulation area.

[0011] The present invention combines the Thomson discharge theory and the streamer discharge theory, and provides a simulation method for the microscopic process of gas discharge and a simulation method for the spatial propagation process of the electromagnetic field; then, on the basis of the two, a simulation model of near-field electromagnetic radiation caused by gas discharge is proposed. The simulation model takes into account the change process of the state of microscopic particles and the influence of the streamer path, so that the simulation result of the electromagnetic radiation process can be obtained.

[0012] Furthermore, in the simulation method described in the present invention, the Poisson equation is used to obtain the electric field distribution at each time step based on the particle state distribution.

[0013] Furthermore, in the simulation method described in the present invention, a finite time-domain difference algorithm is used to obtain electromagnetic field changes in a near-field electromagnetic radiation simulation area.

[0014] Furthermore, in the simulation method described in the present invention, the boundary condition of the finite time-domain difference algorithm is set to a perfectly matched layer boundary.

[0015] Furthermore, in the simulation method described in the present invention, the time step of the near-field electromagnetic radiation simulation satisfies:

[0016]

[0017] Where c represents the speed of light, and Δx, Δy, and Δz represent the size of the grid in the near-field electromagnetic radiation simulation area.

[0018] Another object of the present invention is to provide a simulation system for local discharge and near-field electromagnetic radiation of power equipment, which simulates the gas discharge in the local discharge process to obtain the changes in the state of charged particles and the development process of streamer discharge, as well as its impact on the electromagnetic radiation process, thereby establishing a joint model of the microscopic process of gas discharge and the macroscopic electromagnetic radiation process, thereby more intuitively reflecting the relationship between the two, which is of great significance to the status assessment of power equipment.

[0019] Based on the above purpose, the present invention also provides a simulation system for partial discharge and near-field electromagnetic radiation of power equipment, which includes:

[0020] A gas discharge simulation module simulates the gas discharge process of partial discharge of power equipment, and obtains the particle state distribution at each moment in the gas discharge time based on the model of each particle in the gas discharge; obtains the electric field distribution at each time step based on the particle state distribution; obtains the electric field time sequence change at each excitation source based on several excitation sources set on the gas discharge path and the electric field distribution;

[0021] The near-field electromagnetic radiation module simulates the near-field electromagnetic radiation caused by gas discharge, takes the transient electric field of each excitation source at each simulation moment as the input of the near-field electromagnetic radiation simulation, and obtains the electromagnetic field changes in the near-field electromagnetic radiation simulation area.

[0022] Furthermore, in the simulation system described in the present invention, the gas discharge simulation module uses Poisson's equation to obtain the electric field distribution at each time step based on the particle state distribution.

[0023] Furthermore, in the simulation system described in the present invention, the near-field electromagnetic radiation module uses a finite time-domain difference algorithm to obtain electromagnetic field changes in the near-field electromagnetic radiation simulation area.

[0024] Furthermore, in the simulation system described in the present invention, the boundary condition of the finite time-domain difference algorithm adopted by the near-field electromagnetic radiation module is a perfectly matched layer boundary.

[0025] Furthermore, in the simulation system of the present invention, the time step of the near-field electromagnetic radiation simulation performed by the near-field electromagnetic radiation module satisfies:

[0026]

[0027] Where c represents the speed of light, and Δx, Δy, and Δz represent the size of the grid in the near-field electromagnetic radiation simulation area.

[0028] The simulation method and system for partial discharge and near-field electromagnetic radiation of power equipment described in the present invention have the following advantages and beneficial effects:

[0029] The simulation method and system described in the present invention simulate the gas discharge in the local discharge process to obtain the changes in the state of charged particles and the development process of the streamer discharge, as well as its impact on the electromagnetic radiation process, thereby establishing a joint model of the gas discharge microscopic process and the macroscopic electromagnetic radiation process, thereby more intuitively reflecting the relationship between the two, which is of great significance to the status assessment of power equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure shows the step flow of the simulation method for partial discharge and near-field electromagnetic radiation of electric power equipment in one embodiment of the present invention.

[0031] Figure 2 The figure shows the mesh division of the simulation method for partial discharge and near-field electromagnetic radiation of electric power equipment in one embodiment of the present invention.

[0032] Figure 3 The cell mesh in the finite-difference time-domain method is shown.

[0033] Figure 4 The electric field values ​​at 26 excitation sources at different times in one example are shown.

[0034] Figure 5 Shown is the distribution of electromagnetic fields radiated as a gas discharge develops in a simulation example.

[0035] Figure 6 The diagram shows the architecture of a simulation system for partial discharge and near-field electromagnetic radiation of electric power equipment according to the present invention in one embodiment. DETAILED DESCRIPTION

[0036] The simulation method and system for partial discharge and near-field electromagnetic radiation of power equipment described in the present invention will be further explained and illustrated below in conjunction with the drawings and specific embodiments of the specification. However, such explanation and illustration do not constitute an improper limitation on the technical solution of the present invention.

[0037] In some embodiments, the simulation calculation area consists of two parts, including a gas discharge area and an electromagnetic radiation area. The gas discharge area calculates the time series change of the electric field at the excitation source. The transient electric field at the excitation source is used as the input of the finite time domain difference algorithm calculation area, and then the electromagnetic field change in the simulation area is calculated.

[0038] Figure 1 The figure shows the step flow of the simulation method for partial discharge and near-field electromagnetic radiation of electric power equipment in one embodiment of the present invention.

[0039] Specifically, in one embodiment, a simulation method for partial discharge and near-field electromagnetic radiation of electric power equipment may include the following steps:

[0040] 100: Simulate the gas discharge process of partial discharge of power equipment, and obtain the particle state distribution at each moment in the gas discharge time based on the model of each particle in the gas discharge.

[0041] The main reactions that cause the change in the number of free electrons during gas discharge include: impact ionization, photoionization, adsorption, recombination and diffusion. The above reactions have both effects that increase the number of electrons and effects that decrease the number of electrons, so the final determination of the number of free electrons is the sum of the results of all the above reactions. Similarly, considering the number state of positive ions, the main reactions that cause the change in the number of positive ions include: impact ionization, photoionization, recombination and diffusion. Finally, for negative ions, the main reactions include: adsorption, recombination and diffusion. After considering the above reactions, in some embodiments, the model of each particle in gas discharge can be expressed by formula (1):

[0042]

[0043] Among them, N e , N p , N n Respectively represent the number of free electrons, positive ions and negative ions. α is the impact ionization coefficient, η is the adsorption coefficient, β is the recombination coefficient, and D is the diffusion coefficient. e , v p , v n Respectively represent the migration speed of free electrons, positive ions and negative ions. t represents time, S ph is the photoionization term.

[0044] According to formula (1), the particle state distribution at each moment during the gas discharge time can be calculated.

[0045] In the area of ​​gas discharge simulation, seed electrons are set as the starting condition for discharge. Under the action of the electric field, the seed electrons move quickly and collide with neutral molecules for ionization. Combined with the recombination and diffusion effects of the particles themselves, the state of the charged particles changes. During the change process, the number of particles in each item remains balanced, and the state change process satisfies formula (1).

[0046] When the number of charged particles changes, that is, N in formula (1) e , N p , N n The size and spatial distribution of the quantity change, and the spatial electric field will be affected by it.

[0047] 200: Obtain the electric field distribution at each time step based on the particle state distribution.

[0048] The free charges carried by these charged particles gathered in space will affect the electromagnetic field distribution in space. In some more specific implementations, the electric field distribution E at each time step can be calculated using the Poisson equation:

[0049]

[0050] in, is the spatial potential distribution, ε is the relative dielectric constant of the medium, and q is the unit charge.

[0051] According to formula (2), the electric field distribution in the space after the number of particles changes can be calculated, and the electric field distribution E at each step length can be recorded.

[0052] After the electric field changes, the parameters in formula (1) are updated, and the state change of the current charged particle after the next time step is continuously calculated until the gas discharge ends.

[0053] 300: Based on a plurality of excitation sources arranged on the gas discharge path and the electric field distribution, obtaining a time-series change of the electric field at each excitation source.

[0054] Multiple excitation sources are set on the discharge path of gas discharge to characterize the transient process of the spatial electric field. The number of excitation sources can be determined according to the electrode gap and the grid size. In a specific example, for an electrode gap of 1 cm, combined with the grid size, 26 excitation sources can be set and evenly distributed on the discharge path of gas discharge. The simulation setting diagram is shown in the figure. Figure 2 shown.

[0055] As described above, the gas discharge process causes a time-sequential change in the electric field. In some embodiments, 26 excitation sources are selected to simulate the electromagnetic changes on the streamer path. Therefore, according to the coordinates of each excitation source, the electric field value of the excitation source in each time step is found from the electric field distribution E obtained in step 200, and the time-sequential electric field changes on the 26 excitation sources can be obtained.

[0056] 400: Simulate the near-field electromagnetic radiation caused by the gas discharge, use the transient electric field of each excitation source at each simulation moment as the input of the near-field electromagnetic radiation simulation, and obtain the electromagnetic field change in the near-field electromagnetic radiation simulation area.

[0057] In some more specific implementations, a finite time-domain difference algorithm is used to obtain electromagnetic field changes in a near-field electromagnetic radiation simulation area.

[0058] The process of gas discharge generating electromagnetic signals is essentially the rapid change of the air gap electric field caused by the change of the state of charged particles during the discharge process. This change is widely propagated in space in the form of electromagnetic waves. Therefore, the principle of electromagnetic wave excitation can be explained by Maxwell's equations combined with the charge changes in the gas discharge process described above. Maxwell's equations are shown in equation (3).

[0059]

[0060] In formula (3), E represents electric field distribution or electric field, B represents magnetic field or magnetic field distribution, ε is vacuum dielectric constant, μ is vacuum magnetic permeability, ρ is space charge, and J is space current.

[0061] Maxwell's equations can be solved using the finite time-domain (FDTD) algorithm, which aims to use the central difference method to find the approximate solution of the curl equations in Maxwell's equations in terms of spatial distribution, and then calculate the change of the electromagnetic field over time. The FDTD algorithm mainly consists of three parts: grid division, difference format and boundary conditions.

[0062] Consider sampling the electric field E component and the magnetic field H component in space, and consider that the electric field E and the magnetic field H are alternately distributed in space in accordance with the conditions of Ampere's law and Faraday's law of electromagnetic induction. Each electric field component is surrounded by four magnetic field H components, and each magnetic field H component is surrounded by four electric field E components. The sampling is alternated in time, and the difference is half a time step. The schematic diagram of the unit grid is shown in Figure 3. Under the central approximate difference format, the Maxwell equations in the continuous differential form in space and time are converted into a set of approximate difference equations, and the electromagnetic field in space is solved as the time step advances.

[0063] The iterative derivation of the FDTD algorithm is based on the central difference approximation to replace the differential equation. Considering the passive calculation space, the Maxwell equations can be simplified to the following form:

[0064]

[0065] Where E is the electric field distribution, H is the magnetic field distribution, σ m and σ e Denote electrical conductivity and magnetic permeability respectively. According to the central difference format, the above divergence equation is discretized and approximated into the equation corresponding to the scalar field component:

[0066]

[0067] In the formula, x, y, z represent the directions of the spatial coordinate axes, i, j, k represent the grid coordinates, n represents the time, and Δt is the time step. Since the grid is a discrete approximation of equation (4), the electric field distribution and the magnetic field distribution have a difference of half a time step in the approximate calculation, which is represented by superscripts n and n+1 / 2 in the formula.

[0068] In the simulation of electromagnetic waves (i.e., near-field electromagnetic radiation simulation), at each simulation moment, the electric field value on each excitation source is assigned according to its time-series electric field change. When the electric field value of the excitation source changes with time, the electromagnetic field in the simulation space begins to propagate, and its propagation iterative process satisfies formula (5).

[0069] When the change value of the electric field of the excitation source ends, the simulation ends. At this time, the electric field value and magnetic field value in the near-field electromagnetic radiation simulation area at different simulation times can be obtained. The change process of the electric field value and magnetic field value in this space can reflect the propagation process of the electromagnetic field.

[0070] In some more specific implementations, the boundary condition of the finite difference time domain algorithm is set to a perfect match layer (PML) boundary.

[0071] Using perfectly matched layer boundaries to simulate open domain calculations can truncate incident electromagnetic waves in the calculation area. The wave impedance of the PML boundary can be perfectly matched with the adjacent medium, so electromagnetic waves in the calculation domain will not be reflected when entering the PML layer. At the same time, electromagnetic waves propagate lossily in the PML and can decay rapidly, thereby achieving complete absorption.

[0072] In some more specific embodiments, the time step of the near-field electromagnetic radiation simulation satisfies:

[0073]

[0074] Where c represents the speed of light, and Δx, Δy, and Δz represent the size of the grid in the near-field electromagnetic radiation simulation area.

[0075] The determination of the time step depends on the stability condition of the numerical calculation, which is determined by the spatial step. Similarly to the size of the spatial step, a smaller time step can better obtain the time resolution of field changes, but it also has higher requirements for computing resources. However, an excessively large time step will lead to oscillation of the numerical calculation. Based on this, in some embodiments of the present invention, the time step of the near-field electromagnetic radiation simulation satisfies formula (6).

[0076] In some embodiments, the near-field radiation region is set as a rectangular region under an ideal propagation state, and in a specific example, its size is x=3.6 cm, y=4.4 cm, z=0.78 cm. The grid size of the FDTD simulation can be Δx=0.4 mm, Δy=0.4 mm, Δz=0.3 mm.

[0077] In a specific example, the discharge and electromagnetic radiation process between parallel plate electrodes is simulated.

[0078] The gas discharge area is divided into triangular grids, and the grid density is increased for the streamer path to achieve simulation accuracy when high-concentration electrons pass through. The electrode spacing is 1 cm and the applied voltage is 52 kV.

[0079] During simulation, the applied voltage induces a high field strength in the air region between the electrodes. The study area of ​​the streamer discharge (FEM) is the central air part.

[0080] During the simulation, electrons move toward the anode driven by an external electric field. A large number of electrons gather near the anode at the head of the streamer, leaving a large amount of positive charge at the tail. The uneven distribution of space charge further leads to the distortion of the electric field in the air gap, which excites electromagnetic waves in space.

[0081] The FDTD method is used to simulate the process of distorted electric fields exciting electromagnetic waves in space. The simulation area is set as a rectangular area under ideal propagation conditions, with dimensions of x = 3.6 cm, y = 4.4 cm, and z = 0.78 cm. The grid size of the FDTD simulation is Δx = 0.4 mm, Δy = 0.4 mm, and Δz = 0.3 mm. The distribution of electromagnetic field components in the grid is as follows: Figure 3 As shown, the grid structure is Figure 2 shown.

[0082] A fully matched layer is set around the simulation area so that the electromagnetic waves transmitted to the boundary are completely absorbed and the interior of the simulation area is not affected by the refraction and reflection of the electromagnetic field.

[0083] Considering the electric field variation process on the streamer discharge (or gas discharge) path, 26 excitation sources are used to describe the influence of the streamer motion path on the electromagnetic field excitation. At the same time, according to formula (6), the time step of the near-field electromagnetic radiation simulation is set.

[0084] Figure 4 and Figure 5 The simulation results of this example are shown respectively.

[0085] in, Figure 4 It shows the electric field values ​​at 26 excitation sources at different times. Figure 4 As shown in the figure, at the beginning, the electric field distribution between the parallel plates is a uniform electric field with a value of 52kV / cm. When a streamer (i.e., gas discharge) occurs, the increase in the absolute value of the electric field is due to the electric field distortion caused by the accumulation of space charges, indicating that the streamer head has reached that position; the decrease in the absolute value of the electric field indicates that the number of charged particles at that location has increased significantly, and the conductivity has increased rapidly, so the electric field strength has decreased, and this usually occurs after the streamer has passed and the location has entered the streamer. Figure 4 As shown, the positions of the 26 excitation points are evenly distributed between the cathode and the anode, and as the discharge process develops, the electric field changes with time.

[0086] Figure 5 The electromagnetic field distribution radiated by the gas discharge jet is given. The figure shows the instantaneous electric field change in the calculation domain. The direction of the electric field is related to Figure 4 The electric field values ​​in the same direction, a positive value means that under the influence of the instantaneous electric field component in the opposite direction, the equivalent electric field value becomes smaller.

[0087] from Figure 5 It can be seen from the figure that during the streamer movement from t = 1345ps to t = 1675ps, the electric field value between the streamer head and the electrode gradually increases, mainly because the distance between the streamer and the electrode decreases and the charge of the streamer head increases, so it radiates electric field radiation in the same direction in the calculation domain. Considering the discharge radiation process from t = 1675ps to t = 1798ps, the electric field amplitude of the area where the streamer passes decreases rapidly at this time, which is shown in the figure as the yellow area expanding to both sides as the streamer develops. At this time, comparing the electric field distribution at t = 1345ps and t = 1798ps, the length of the yellow area, that is, the inner area of ​​the streamer, at t = 1798ps gradually extends compared to that at t = 1345ps. The area where the electric field value decreases radiates a positive electric field outward, that is, the yellow area radiating outward in the figure.

[0088] like Figure 6 As shown, in another embodiment, the present invention further provides a simulation system for partial discharge and near-field electromagnetic radiation of power equipment, which includes:

[0089] The gas discharge simulation module 502 simulates the gas discharge process of partial discharge of the power equipment, and obtains the particle state distribution at each moment in the gas discharge time based on the model of each particle in the gas discharge; obtains the electric field distribution at each time step based on the particle state distribution; obtains the electric field time sequence change at each excitation source based on a number of excitation sources set on the gas discharge path and the electric field distribution;

[0090] The near-field electromagnetic radiation module 504 simulates the near-field electromagnetic radiation caused by gas discharge, uses the transient electric field of each excitation source at each simulation moment as the input of the near-field electromagnetic radiation simulation, and obtains the electromagnetic field changes in the near-field electromagnetic radiation simulation area.

[0091] In some more specific implementations, the gas discharge simulation module 502 uses the Poisson equation to obtain the electric field distribution at each time step based on the particle state distribution.

[0092] In some more specific implementations, the near-field electromagnetic radiation module 504 uses a finite time-domain difference algorithm to obtain electromagnetic field changes in the near-field electromagnetic radiation simulation area.

[0093] In some more specific implementations, the near-field electromagnetic radiation module 504 uses a finite time-domain difference algorithm with a boundary condition of a perfectly matched layer boundary.

[0094] In some more specific implementations, the time step of the near-field electromagnetic radiation simulation performed by the near-field electromagnetic radiation module 504 satisfies:

[0095]

[0096] Where c represents the speed of light, and Δx, Δy, and Δz represent the size of the grid in the near-field electromagnetic radiation simulation area.

[0097] It can be seen that the simulation method and system described in the present invention simulate the gas discharge in the local discharge process, obtain the changes in the state of charged particles and the development process of the streamer discharge, and its impact on the electromagnetic radiation process, thereby establishing a joint model of the gas discharge microscopic process and the macroscopic electromagnetic radiation process, thereby more intuitively reflecting the relationship between the two, which is of great significance to the status assessment of power equipment.

[0098] It should be noted that the prior art in the protection scope of the present invention is not limited to the embodiments given in the present application documents. All prior art that does not contradict the scheme of the present invention, including but not limited to prior patent documents, prior public publications, prior public uses, etc., can be included in the protection scope of the present invention.

[0099] In addition, the combination of the various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them.

[0100] It should also be noted that the above-listed embodiments are only specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or modifications made therewith can be directly derived or easily associated with the contents disclosed by those skilled in the art from the present invention, and all should belong to the protection scope of the present invention.

Claims

1. A simulation method for partial discharge and near-field electromagnetic radiation of power equipment, characterized in that: Includes steps: The gas discharge process of partial discharge of power equipment is simulated, and the particle state distribution at each moment in the gas discharge time is obtained based on the model of each particle in the gas discharge; Obtaining the electric field distribution at each time step based on the particle state distribution; Based on a plurality of excitation sources arranged on the gas discharge path and the electric field distribution, obtaining a time-series change of the electric field at each excitation source; The near-field electromagnetic radiation caused by gas discharge is simulated, and the transient electric field of each excitation source at each simulation moment is used as the input of the near-field electromagnetic radiation simulation to obtain the electromagnetic field changes in the near-field electromagnetic radiation simulation area.

2. The simulation method according to claim 1, characterized in that: The electric field distribution at each time step is obtained based on the particle state distribution using the Poisson equation.

3. The simulation method according to claim 1, characterized in that: The finite time-domain difference algorithm is used to obtain the electromagnetic field changes in the near-field electromagnetic radiation simulation area.

4. The simulation method according to claim 3, characterized in that: The boundary condition of the finite time-domain difference algorithm is set to a perfectly matched layer boundary.

5. The simulation method according to claim 1, characterized in that: The time step of near-field electromagnetic radiation simulation satisfies: Where c represents the speed of light, and Δx, Δy, and Δz represent the size of the grid in the near-field electromagnetic radiation simulation area.

6. A simulation system for partial discharge and near-field electromagnetic radiation of power equipment, characterized in that: include: A gas discharge simulation module simulates the gas discharge process of partial discharge of power equipment, and obtains the particle state distribution at each moment in the gas discharge time based on the model of each particle in the gas discharge; obtains the electric field distribution at each time step based on the particle state distribution; obtains the electric field time sequence change at each excitation source based on several excitation sources set on the gas discharge path and the electric field distribution; The near-field electromagnetic radiation module simulates the near-field electromagnetic radiation caused by gas discharge, takes the transient electric field of each excitation source at each simulation moment as the input of the near-field electromagnetic radiation simulation, and obtains the electromagnetic field changes in the near-field electromagnetic radiation simulation area.

7. The simulation system according to claim 6, characterized in that: The gas discharge simulation module uses Poisson's equation to obtain the electric field distribution at each time step based on the particle state distribution.

8. The simulation system according to claim 6, characterized in that: The near-field electromagnetic radiation module uses a finite time-domain difference algorithm to obtain electromagnetic field changes in a near-field electromagnetic radiation simulation area.

9. The simulation system according to claim 8, characterized in that: The near-field electromagnetic radiation module adopts a finite time-domain difference algorithm whose boundary condition is a perfectly matched layer boundary.

10. The simulation system according to claim 6, characterized in that: The time step of the near-field electromagnetic radiation module for near-field electromagnetic radiation simulation satisfies: Where c represents the speed of light, and Δx, Δy, and Δz represent the size of the grid in the near-field electromagnetic radiation simulation area.

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