Method and device for predicting breakdown voltage of high-voltage dry air

Abstract

The invention discloses a high-voltage dry air breakdown voltage prediction method and device, and the method comprises the steps: building a simulation model through physical field simulation software, considering a field intensity enhancement factor caused by electrode protrusion, and calculating the instantaneous electric field distribution, critical volume and effective critical emission area of a spherical electrode geometric model, the method comprises the following steps: considering volume change and time factors in a gas discharge process, introducing a volume-time theory, calculating an initial electron generation probability in each time step length, calculating an impulse voltage breakdown probability according to the initial electron generation probability, then increasing the impulse voltage on a spherical electrode geometric model according to a preset voltage increment, and calculating the impulse voltage breakdown probability according to the preset voltage increment. According to the method, the impulse voltage breakdown probability corresponding to each impulse voltage is obtained, the breakdown behavior of the high-voltage dry air under the impulse voltage can be accurately simulated and predicted, the accuracy and reliability of dry air breakdown voltage prediction are improved, and a scientific basis is provided for insulation design of the dry air in high-voltage equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage direct current power transmission, and in particular to a method and device for predicting the breakdown voltage of high-voltage dry air. Background Art

[0002] Due to its excellent insulation performance, it is widely used in the insulation of high-voltage equipment such as gas-insulated switchgear GIS and gas-insulated transmission lines. has a high global warming potential and is subject to emission control targets. There is a great need for alternative gases.

[0003] Dry air has no global warming potential and no ozone depletion potential. Therefore, dry air is a sustainable and better Alternative gas. The insulating properties of dry air are approximately When high-voltage equipment uses dry air, some measures must be taken to improve insulation performance. Dry air GIS has limited insulation performance, mostly limited to medium voltage (72kV) and below. Existing methods improve dry air insulation performance by increasing gas pressure, but excessive pressure will cause gas liquefaction and increase manufacturing costs. Therefore, it is necessary to predict the breakdown voltage of dry air when it is used in actual equipment to optimize insulation design and ensure reliability. Summary of the invention

[0004] The present invention provides a method and device for predicting the breakdown voltage of high-voltage dry air, which are used to accurately simulate and predict the breakdown behavior of high-voltage dry air under impulse voltage, thereby improving the accuracy and reliability of dry air breakdown voltage prediction.

[0005] In view of this, a first aspect of the present invention provides a method for predicting the breakdown voltage of high-voltage dry air, comprising:

[0006] S1. According to the actual dry air breakdown voltage experimental scenario, a simulation model is established in the physical field simulation software. The simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters;

[0007] S2. In the simulation model, the impulse voltage on the spherical electrode geometric model is set and the electrode surface roughness factor is added to calculate the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model considering the surface roughness;

[0008] S3. When the critical volume satisfies both the ionization coefficient greater than the attachment coefficient and the stream column starting criteria, the initial electron generation probability in each time step is calculated according to the critical volume and the effective critical emission area, and the impulse voltage breakdown probability is calculated according to the initial electron generation probability;

[0009] S4, determine whether the current time reaches the impulse voltage end time, if so, output the impulse voltage breakdown probability at the current time, and execute step S5, otherwise, increase the current time by the time step and return to step S2;

[0010] S5. Determine whether the impulse voltage breakdown probability at the current time reaches 100%. If so, stop the simulation. If not, increase the impulse voltage on the spherical electrode geometric model by a preset voltage increment and return to step S2.

[0011] Optionally, in step S3, the mathematical model for calculating the impulse voltage breakdown probability is:

[0012]

[0013] Among them, P is the impulse voltage breakdown probability, t is the time, is the critical volume, dV is The differential of is the effective critical emission area, is the ionization coefficient, is the adhesion coefficient, dS is the The differential of , j is the current density, e is the elementary charge, It is the number of electrons that are separated from negative ions in dry air per unit volume and time.

[0014] Optionally, the physical field simulation software is COMSOL multi-physics field simulation software.

[0015] Optionally, the stream column starting criteria are:

[0016]

[0017] Where K is the critical avalanche number, is the ionization coefficient, is the adhesion coefficient, is the critical avalanche length, dx is The differential of .

[0018] Optionally, the current density is calculated as:

[0019]

[0020]

[0021]

[0022] in, is the field strength enhancement factor, is the work function of the electrode metal, and E is the electric field intensity on the electrode surface.

[0023] A second aspect of the present invention provides a high-voltage dry air breakdown voltage prediction device, comprising:

[0024] A modeling unit is used to establish a simulation model in a physical field simulation software according to an actual dry air breakdown voltage experimental scenario, wherein the simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters;

[0025] The first calculation unit is used to set the impulse voltage on the spherical electrode geometric model and add the electrode surface roughness factor in the simulation model, and calculate the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model considering the surface roughness;

[0026] The second calculation unit is used to calculate the probability of initial electron generation in each time step according to the critical volume and the effective critical emission area when the critical volume satisfies both the ionization coefficient being greater than the attachment coefficient and the stream column starting criterion, calculate the impulse voltage breakdown probability according to the initial electron generation probability, and execute the first judgment unit;

[0027] The first judgment unit is used to judge whether the current time reaches the impulse voltage end time. If so, the impulse voltage breakdown probability at the current time is output and the second judgment unit is executed. Otherwise, the current time is increased by the time step and the first calculation unit is returned to execute.

[0028] The second judgment unit is used to judge whether the impulse voltage breakdown probability at the current time reaches 100%. If so, the simulation is stopped; if not, the impulse voltage on the spherical electrode geometric model is increased by a preset voltage increment and the program is returned to execute the first calculation unit.

[0029] Optionally, in the second calculation unit, a mathematical model for calculating the impulse voltage breakdown probability is:

[0030]

[0031] Among them, P is the impulse voltage breakdown probability, t is the time, is the critical volume, dV is The differential of is the effective critical emission area, is the ionization coefficient, is the adhesion coefficient, dS is the The differential of , j is the current density, e is the elementary charge, It is the number of electrons that are separated from negative ions in dry air per unit volume and time.

[0032] Optionally, the physical field simulation software is COMSOL multi-physics field simulation software.

[0033] Optionally, the stream column starting criteria are:

[0034]

[0035] Where K is the critical avalanche number, is the ionization coefficient, is the adhesion coefficient, is the critical avalanche length, dx is The differential of .

[0036] Optionally, the current density is calculated as:

[0037]

[0038]

[0039]

[0040] in, is the field strength enhancement factor, is the work function of the electrode metal, and E is the electric field intensity on the electrode surface.

[0041] It can be seen from the above technical solutions that the high-pressure dry air breakdown voltage prediction method provided by the present invention has the following advantages:

[0042] The high-voltage dry air breakdown voltage prediction method provided by the present invention uses physical field simulation software to establish a simulation model, considers the field strength enhancement factor caused by electrode protrusion, calculates the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model, considers the volume change and time factor in the gas discharge process, introduces the volume-time theory, calculates the initial electron generation probability in each time step, calculates the impulse voltage breakdown probability according to the initial electron generation probability, and then increases the impulse voltage on the spherical electrode geometric model according to a preset voltage increment to obtain the impulse voltage breakdown probability corresponding to each impulse voltage. The method can accurately simulate and predict the breakdown behavior of high-voltage dry air under impulse voltage, improve the accuracy and reliability of dry air breakdown voltage prediction, and provide a scientific basis for the insulation design of dry air in high-voltage equipment.

[0043] At the same time, the high-pressure dry air breakdown voltage prediction method provided by the present invention uses the volume-time theory for prediction, which can greatly reduce the number of experiments, reduce the test cost, and improve the research and development efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic flow chart of a method for predicting breakdown voltage of high-voltage dry air provided in an embodiment of the present invention;

[0046] Figure 2 A schematic diagram of the critical volume and effective critical emission area under an applied voltage of 280 kV and a pressure of 0.95 MPa provided in an embodiment of the present invention;

[0047] Figure 3 A simplified schematic diagram of the electric field around a protrusion on the surface of a spherical electrode provided in an embodiment of the present invention;

[0048] Figure 4 A schematic diagram of experimental results and predicted values ​​of the positive electrode breakdown probability provided in an embodiment of the present invention;

[0049] Figure 5 It is a schematic structural diagram of a high-voltage dry air breakdown voltage prediction device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] The terms "first", "second", "third", "fourth", etc. (if any) in the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0052] For easier understanding, see Figure 1 The present invention provides an embodiment of a method for predicting a breakdown voltage of high-voltage dry air, comprising:

[0053] Step S1: According to the actual dry air breakdown voltage experimental scenario, a simulation model is established in a physical field simulation software, wherein the simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters.

[0054] It should be noted that a simulation model matching the actual dry air breakdown voltage experimental scenario is established in the physical field simulation software, and the simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters. The physical field simulation software uses COMSOL multi-physics field simulation software.

[0055] Step S2: In the simulation model, the impulse voltage on the spherical electrode geometric model is set and the electrode surface roughness factor is added to calculate the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model considering the surface roughness.

[0056] It should be noted that in the simulation model, the impulse voltage U(t) is set on the spherical electrode geometric model. There are many tiny protrusions on the surface of the spherical electrode. The electric field concentration of these protrusions in the high-pressure gas has a significant effect on the breakdown voltage. Therefore, it is necessary to consider the influencing factors of the electrode surface roughness. According to the impulse voltage U(t) on the spherical electrode geometric model and the electrode surface roughness factor, the instantaneous electric field distribution of the spherical electrode geometric model considering the surface roughness can be calculated using the electric field calculation function of the physical field simulation software. Based on the instantaneous electric field distribution, the critical volume can be determined. and effective emission area .

[0057] Step S3, when the critical volume satisfies both the ionization coefficient being greater than the attachment coefficient and the stream column starting criteria, the initial electron generation probability in each time step is calculated according to the critical volume and the effective critical emission area, and the impulse voltage breakdown probability is calculated according to the initial electron generation probability.

[0058] It should be noted that the definition of critical volume Two conditions must be met at the same time: ionization coefficient Greater than the adhesion coefficient The dry air has the conditions for breakdown only if the column starts with the following criteria:

[0059]

[0060] Where K is the critical avalanche number, is the ionization coefficient, is the adhesion coefficient, is the critical avalanche length, dx is The streamer initiation criterion formula means that when the number of electrons in an electron avalanche drifting in the electric field reaches a certain threshold, it will transform into a streamer discharge. The critical avalanche number is recorded as (e=2.718; K=18), approximately . and The calculations were performed using BOLSIG+ software, and the cross-sectional data for oxygen and nitrogen were taken from the Phelps database. = The critical electric field About 115Td.

[0061] According to the critical volume Calculate the probability of initial electron generation in the dry air within the time increment Δt and integrate this probability. Then, the probability of initial electron generation in the electrode field emission within the time increment Δt is calculated relative to the effective emission area. Integrate to obtain the total initial electron generation probability within a time step. After that, increase the time t = t+Δt to enter the calculation of the next time step. Repeat the above calculation process until the entire process of impulse voltage application is simulated.

[0062] The mathematical model for calculating the impulse voltage breakdown probability is:

[0063]

[0064] Among them, P is the impulse voltage breakdown probability, t is the time, is the critical volume, dV is The differential of is the effective critical emission area, is the ionization coefficient, is the adhesion coefficient, dS is the The differential of , j is the current density, e is the elementary charge, The electron detachment coefficient is the number of electrons detached from negative ions in dry air per unit volume and time. and negative ion density It means that its expression is To simplify the calculation, assume that the pressure in the air is 0.1 MPa. density Since the rate of ion generation from cosmic rays is proportional to the pressure, and the diffusion coefficient is inversely proportional to the pressure, the negative ion density is assumed to be proportional to the square of the pressure p: .

[0065] The calculation formula of current density j is:

[0066]

[0067]

[0068]

[0069] in, is the field strength enhancement factor, is the work function of the electrode metal, and E is the electric field intensity on the electrode surface.

[0070] That is, the calculation formula of the above current density j can be expressed as:

[0071]

[0072] Work function of electrode metal Set to 4.5 eV, The value is based on the assumed aspect ratio of the microprotrusions a / b. In the presence of microprotrusions on the electrode surface, cathodic field emission based on the FN equation is expected to be observed at electric fields of tens of kilovolts per millimeter. By dividing the current density j by the elementary charge e = , we can get the number of electrons emitted per unit area and time as the electric field changes, such as Figure 2 As shown, the critical area is defined as To pass The area where the electric field lines leave the electrode surface. Assume that the electrode surface is uniformly distributed with protrusions of height a (12µm) and radius b (1µm), with a spacing of W (20µm), such as Figure 3 As shown, more precisely, electrons are emitted only from the electric field enhancement region at the tip of the microprotrusion. Assuming that the electric field is enhanced in the hemispherical region (radius b) at the tip of the protrusion, the effective critical area is replace By the effective critical area By integrating j / e, the number of electrons emitted from the electrode surface that develop into an electron avalanche per unit time can be determined.

[0073] Step S4, determine whether the current time reaches the impulse voltage end time, if so, output the impulse voltage breakdown probability at the current time, and execute step S5, otherwise, increase the current time by the time step and return to step S2.

[0074] It should be noted that within each time step of the impulse voltage application, the probability of initial electron generation is calculated, and these probabilities are accumulated to calculate the impulse voltage breakdown probability within that time. When the impulse voltage ends, the breakdown probability during the entire impulse voltage application process can be finally obtained. This breakdown probability can be used as an indicator to assess the breakdown risk of high-voltage dry air under specific conditions. According to the calculated breakdown probability, the experimental results are analyzed and optimized. By adjusting the model parameters, optimizing the calculation process, etc., the accuracy of the prediction can be improved, providing a more reliable basis for the design and operation of high-voltage electrical equipment.

[0075] Step S5, determine whether the impulse voltage breakdown probability at the current time reaches 100%, if so, stop the simulation, if not, increase the impulse voltage on the spherical electrode geometric model by a preset voltage increment, and return to step S2.

[0076] It should be noted that, according to the breakdown probability corresponding to the current impulse voltage, it is judged whether the impulse voltage breakdown probability reaches 100%. If so, the simulation is stopped. Otherwise, the impulse voltage on the spherical electrode geometric model continues to increase according to the preset voltage increment, that is, . Then return to step S2 to continue execution.

[0077] like Figure 4 As shown, the high-pressure dry air breakdown voltage prediction method provided by the present invention can quickly and accurately predict the breakdown voltage under different conditions by applying the volume-time theory, thereby reducing the need to rely on experiments, and can greatly reduce the number of experiments and reduce the test cost. In addition, since the method is based on theoretical derivation, its results are more universal and repeatable.

[0078] The high-voltage dry air breakdown voltage prediction method provided by the present invention uses physical field simulation software to establish a simulation model, considers the field strength enhancement factor caused by electrode protrusion, calculates the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model, considers the volume change and time factor in the gas discharge process, introduces the volume-time theory, calculates the initial electron generation probability in each time step, calculates the impulse voltage breakdown probability according to the initial electron generation probability, and then increases the impulse voltage on the spherical electrode geometric model according to a preset voltage increment to obtain the impulse voltage breakdown probability corresponding to each impulse voltage. The method can accurately simulate and predict the breakdown behavior of high-voltage dry air under impulse voltage, improve the accuracy and reliability of dry air breakdown voltage prediction, and provide a scientific basis for the insulation design of dry air in high-voltage equipment.

[0079] At the same time, the high-pressure dry air breakdown voltage prediction method provided by the present invention uses the volume-time theory for prediction, which can greatly reduce the number of experiments, reduce the test cost, and improve the research and development efficiency.

[0080] For easier understanding, see Figure 5 The present invention provides an embodiment of a high-voltage dry air breakdown voltage prediction device, comprising:

[0081] A modeling unit is used to establish a simulation model in a physical field simulation software according to an actual dry air breakdown voltage experimental scenario, wherein the simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters;

[0082] The first calculation unit is used to set the impulse voltage on the spherical electrode geometric model and add the electrode surface roughness factor in the simulation model, and calculate the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model considering the surface roughness;

[0083] The second calculation unit is used to calculate the probability of initial electron generation in each time step according to the critical volume and the effective critical emission area when the critical volume satisfies both the ionization coefficient being greater than the attachment coefficient and the stream column starting criterion, calculate the impulse voltage breakdown probability according to the initial electron generation probability, and execute the first judgment unit;

[0084] The first judgment unit is used to judge whether the current time reaches the impulse voltage end time. If so, the impulse voltage breakdown probability at the current time is output and the second judgment unit is executed. Otherwise, the current time is increased by the time step and the first calculation unit is returned to execute.

[0085] The second judgment unit is used to judge whether the impulse voltage breakdown probability at the current time reaches 100%. If so, the simulation is stopped; if not, the impulse voltage on the spherical electrode geometric model is increased by a preset voltage increment and the program is returned to execute the first calculation unit.

[0086] In the second calculation unit, the mathematical model for calculating the impulse voltage breakdown probability is:

[0087]

[0088] Among them, P is the impulse voltage breakdown probability, t is the time, is the critical volume, dV is The differential of is the effective critical emission area, is the ionization coefficient, is the adhesion coefficient, dS is the The differential of , j is the current density, e is the elementary charge, It is the number of electrons that are separated from negative ions in dry air per unit volume and time.

[0089] The physical field simulation software is COMSOL multi-physics field simulation software.

[0090] The flow column initiation criteria are:

[0091]

[0092] Where K is the critical avalanche number, is the ionization coefficient, is the adhesion coefficient, is the critical avalanche length, dx is The differential of .

[0093] The calculation formula for current density is:

[0094]

[0095]

[0096]

[0097] in, is the field strength enhancement factor, is the work function of the electrode metal, and E is the electric field intensity on the electrode surface.

[0098] The high-pressure dry air breakdown voltage prediction device provided in the present invention is used to execute the high-pressure dry air breakdown voltage prediction method provided in the present invention. Its principle and technical effects are the same as those of the high-pressure dry air breakdown voltage prediction method provided in the present invention, and will not be repeated here.

[0099] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for predicting breakdown voltage of high-voltage dry air, characterized in that: include: S1. According to the actual dry air breakdown voltage experimental scenario, a simulation model is established in the physical field simulation software. The simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters; S2. In the simulation model, the impulse voltage on the spherical electrode geometric model is set and the electrode surface roughness factor is added to calculate the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model considering the surface roughness; S3. When the critical volume satisfies both the ionization coefficient greater than the attachment coefficient and the stream column starting criteria, the initial electron generation probability in each time step is calculated according to the critical volume and the effective critical emission area, and the impulse voltage breakdown probability is calculated according to the initial electron generation probability; S4, determine whether the current time reaches the impulse voltage end time, if so, output the impulse voltage breakdown probability at the current time, and execute step S5, otherwise, increase the current time by the time step and return to step S2; S5. Determine whether the impulse voltage breakdown probability at the current time reaches 100%. If so, stop the simulation. If not, increase the impulse voltage on the spherical electrode geometric model by a preset voltage increment and return to step S2.

2. The high-pressure dry air breakdown voltage prediction method according to claim 1, characterized in that: In step S3, the mathematical model for calculating the impulse voltage breakdown probability is: Among them, P is the impulse voltage breakdown probability, t is the time, is the critical volume, dV is the The differential of is the effective critical emission area, is the ionization coefficient, is the adhesion coefficient, dS is the The differential of , j is the current density, e is the elementary charge, It is the number of electrons that are separated from negative ions in dry air per unit volume and time.

3. The high-pressure dry air breakdown voltage prediction method according to claim 1, characterized in that: The physical field simulation software is COMSOL multi-physics field simulation software.

4. The high-pressure dry air breakdown voltage prediction method according to claim 1, characterized in that: The flow column initiation criteria are: Where K is the critical avalanche number, is the ionization coefficient, is the adhesion coefficient, is the critical avalanche length, dx is The differential of .

5. The method for predicting the breakdown voltage of high-pressure dry air according to claim 2, characterized in that: The calculation formula for current density is: in, is the field strength enhancement factor, is the work function of the electrode metal, and E is the electric field intensity on the electrode surface.

6. A high-pressure dry air breakdown voltage prediction device, characterized in that: include: A modeling unit is used to establish a simulation model in a physical field simulation software according to an actual dry air breakdown voltage experimental scenario, wherein the simulation model includes a spherical electrode geometry model, a voltage application method, and gas environment parameters; The first calculation unit is used to set the impulse voltage on the spherical electrode geometric model and add the electrode surface roughness factor in the simulation model, and calculate the instantaneous electric field distribution, critical volume and effective critical emission area of ​​the spherical electrode geometric model considering the surface roughness; The second calculation unit is used to calculate the probability of initial electron generation in each time step according to the critical volume and the effective critical emission area when the critical volume satisfies both the ionization coefficient being greater than the attachment coefficient and the stream column starting criterion, calculate the impulse voltage breakdown probability according to the initial electron generation probability, and execute the first judgment unit; The first judgment unit is used to judge whether the current time reaches the impulse voltage end time. If so, the impulse voltage breakdown probability at the current time is output and the second judgment unit is executed. Otherwise, the current time is increased by the time step and the first calculation unit is returned to execute. The second judgment unit is used to judge whether the impulse voltage breakdown probability at the current time reaches 100%. If so, the simulation is stopped; if not, the impulse voltage on the spherical electrode geometric model is increased by a preset voltage increment and the program is returned to execute the first calculation unit.

7. The high-pressure dry air breakdown voltage prediction device according to claim 6, characterized in that: In the second calculation unit, the mathematical model for calculating the impulse voltage breakdown probability is: Among them, P is the impulse voltage breakdown probability, t is the time, is the critical volume, dV is the The differential of is the effective critical emission area, is the ionization coefficient, is the adhesion coefficient, dS is the The differential of , j is the current density, e is the elementary charge, It is the number of electrons that are separated from negative ions in dry air per unit volume and time.

8. The high-pressure dry air breakdown voltage prediction device according to claim 6, characterized in that: The physical field simulation software is COMSOL multi-physics field simulation software.

9. The high-pressure dry air breakdown voltage prediction device according to claim 6, characterized in that: The flow column initiation criteria are: Where K is the critical avalanche number, is the ionization coefficient, is the adhesion coefficient, is the critical avalanche length, dx is The differential of .

10. The high-pressure dry air breakdown voltage prediction device according to claim 7, characterized in that: The calculation formula for current density is: in, is the field strength enhancement factor, is the work function of the electrode metal, and E is the electric field intensity on the electrode surface.

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