Design method of light-weight DC GIS circular-arc transition type vented pot-type insulator

Abstract

The application provides a design method of a light-weight DC GIS circular-arc transition type vented pot-type insulator, comprising the following steps: establishing a geometric model of a vented pot-type insulator, and importing the model into a finite element simulation software; setting a temperature physical field in the finite element simulation software according to the actual heat source distribution and heat transfer in a pipeline; taking the calculated insulator temperature as an initial value to bring in an electrostatic physical field considering surface charge accumulation to obtain the insulator surface charge and the along-surface electric field distribution, and judging whether the insulator requirement is met; if not, adjusting the size, shape and position of the through hole and calculating again; if yes, establishing a stress physical field, and performing stress checking on the insulator in a transportation state and a pipeline vertical installation state, and judging whether the mechanical requirement is met; if not, adjusting the size, shape and position of the through hole and repeating the above steps; and through continuously optimizing the through hole structure, the design of the DC GIS vented pot-type insulator is completed.

Description

Technical Field

[0001] This application belongs to the field of insulator technology, and in particular relates to a design method for a lightweight DC GIS arc transition type ventilated basin insulator. Background Technology

[0002] The utilization of offshore wind power is a crucial aspect, and offshore wind farms are thus gradually exhibiting new characteristics such as being far from shore, wading in deep waters, and having large capacities. Given the complex offshore environment and the extremely limited space on offshore platforms, as well as the high difficulty of construction, the construction of converter platforms in offshore wind power bases urgently requires lightweight and compact DC gas-insulated switchgear (GIS) that requires less land occupation and has less environmental impact.

[0003] Basin insulators are core insulation components of GIS equipment. The adoption of lightweight DC GIS ventilated basin insulators can reduce the weight of GIS equipment, thereby reducing the difficulty of long-distance sea transportation and supporting the construction of lightweight offshore wind power platforms. However, under DC voltage, charge accumulates on the insulator surface, leading to local electric field distortion, which is one of the important causes of surface flashover and has become a bottleneck problem in the design of DC GIS and GIL systems. Through-holes are equivalent to introducing a huge defect into DC GIS basin insulators, which will inevitably further aggravate the accumulation of surface charge. This also makes it impossible to directly apply lightweight GIS ventilated basin insulators that have been successfully put into operation in AC systems to DC systems. Summary of the Invention

[0004] 1. Technical problems to be solved Under DC voltage, charge accumulation occurs on the surface of insulators, leading to local electric field distortion and posing a risk of surface flashover. Opening a hole in a ±550kV DC GIS vented basin insulator is equivalent to introducing a large defect inside the insulator, further exacerbating charge accumulation. Currently, there is no reasonable design solution for ±550kV DC GIS vented basin insulators. This application provides a lightweight design method for a DC GIS arc transition type vented basin insulator.

[0005] 2. Technical Solution

[0006] To achieve the above objectives, this application provides a lightweight DC GIS arc transition type vented basin insulator design method, the method comprising the following steps: establishing a geometric model of a ±550kV DC GIS vented basin insulator, and importing the geometric model into finite element simulation software; based on the actual heat source distribution and heat transfer conditions within the pipeline, setting a temperature physical field, an electric field physical field, and a stress calculation physical field in the finite element simulation software; calculating the temperature distribution of the ±550kV DC GIS vented basin insulator based on the temperature physical field; and calculating the ±550kV DC GIS vented basin insulator based on the temperature distribution and the electric field physical field. The surface charge and electric field distribution along the surface of the 0kV DC GIS vented basin insulator are analyzed to determine whether they meet the insulation requirements. If not, the size, shape, and position of the through-hole are adjusted and the calculation is repeated. If the insulation requirements are met, stress verification is performed on the ±550kV DC GIS vented basin insulator under transportation and vertical pipeline installation conditions to determine whether it meets the mechanical requirements. If not, the size, shape, and position of the through-hole are adjusted and the above steps are repeated. By continuously optimizing the through-hole structure, the design of the ±550kV DC GIS vented basin insulator is completed.

[0007] Another embodiment provided in this application is: the finite element simulation software includes a temperature calculation module, an electric field calculation module, and a stress calculation module connected in sequence.

[0008] Another embodiment provided in this application is: the temperature physical field is a laminar flow physical field, a solid and fluid heat transfer physical field, and a surface-to-surface radiation physical field, and the laminar flow physical field and the solid and fluid heat transfer physical field are coupled through non-isothermal heat transfer multi-physics field coupling.

[0009] Another implementation method provided in this application is as follows: in the simulation model, the power of the conductor rod heating is replaced with the Dirichlet boundary condition of temperature, and the temperature calculation module is used to calculate the temperature of the geometric model to obtain the temperature distribution of the ±550kV DC GIS vented basin insulator.

[0010] Sometimes the power is difficult to estimate, and in insulation tests under actual temperature gradients, the heat source is often set to a constant temperature rather than a constant power. Therefore, the power of the conductor heating is replaced by the Dirichlet boundary condition of temperature.

[0011] Another implementation method provided in this application is to input the temperature value in the temperature distribution as an invariant into the electric field calculation module to calculate the surface electric field distribution of the insulator under DC steady state and DC superimposed lightning impacts of different polarities.

[0012] Another embodiment provided in this application is: the electric field physical field is a physical field used according to the conductivity model and the surface charge accumulation mechanism, and the electric field physical field is a rare matter transport physical field, an electrostatic physical field, a domain differential algebraic equation physical field and a boundary differential algebraic equation physical field.

[0013] Another implementation provided by this application is: calculating the change of space charge inside the insulator through the domain ordinary differential physical field and the domain differential algebraic equation physical field in the electric field calculation module, and calculating the change of surface charge of the insulator through the boundary ordinary differential physical field and the boundary differential algebraic equation physical field in the electric field calculation module.

[0014] Another implementation method provided in this application is: the surface charge takes into account three mechanisms: insulator volume current accumulation, insulator surface current accumulation, and insulating gas volume current accumulation.

[0015] Another implementation method provided in this application is as follows: in the rare matter transport physical field, the transport equation of charged particles is used to construct the ion flow field in the gas under the DC electric field; when dividing the grid, a free triangular grid is created on the boundary of the insulator surface to refine it.

[0016] Before computation, a mesh needs to be generated. Currently, multiphysics calculations mainly use the finite element method (FEM). The essence of the FEM is to discretize a complex continuum into a finite number of simple, easily solvable elements. By solving the physical equations of these elements and then combining them, an approximate solution for the entire complex system can be obtained. Theoretically, the finer the mesh, the better; however, a finer mesh will greatly increase the computational load. Therefore, it is necessary to reasonably divide the mesh size, making it appropriately finer in certain critical locations, such as through-holes, while coarser in other locations.

[0017] Another embodiment provided in this application is that the through hole is a double-arc transition type through hole.

[0018] 3. Beneficial effects

[0019] Compared with existing technologies, the beneficial effects of the lightweight DC GIS arc transition type ventilated basin insulator design method provided in this application are as follows: The lightweight DC GIS arc transition type vented basin insulator design method provided in this application optimizes the structure of the through hole to effectively suppress the accumulation of surface charge and reduce the field strength along the surface of the insulator, thereby ensuring that the lightweight ±550kV DC GIS arc transition type vented basin insulator can operate stably in DC GIS.

[0020] The lightweight DC GIS arc transition type ventilated basin insulator design method provided in this application enables the ventilated basin insulator to operate stably under ±550kV DC voltage, providing support for the development of DC GIS. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the design process for the lightweight ±550kV DC GIS arc transition type ventilated basin insulator of this application. Figure 2 This is a schematic diagram of the geometric structure of the lightweight ±550kV DC GIS arc transition type ventilated basin insulator of this application. Figure 3 This is a schematic diagram of the geometric dimensions of the lightweight ±550kV DC GIS arc transition type ventilated basin insulator of this application. Figure 4 This is a schematic diagram of multiphysics coupling in this application; Figure 5 This is a schematic diagram showing the location and geometric dimensions of the through holes in this application; Figure 6 This is a schematic diagram showing the change of the surface electric field distribution of the insulator under DC voltage over time according to this application. Figure 7 This is a schematic diagram of the surface electric field distribution of an insulator under DC superimposed same polarity lightning impulses according to this application. Figure 8 This is a schematic diagram of the surface electric field distribution of an insulator under DC superimposed opposite polarity lightning impulses according to this application. Figure 9 This is a schematic diagram of the stress distribution of the insulator under different conditions in this application; Figure 10 This is a schematic diagram of the surface charge density of the insulator under different through-hole sizes according to this application; Figure 11 This is a schematic diagram of the surface electric field strength of insulators with different through-hole shapes according to this application; Figure 12 This is a schematic diagram of the surface field strength of insulators at different through-hole positions under DC superimposed opposite polarity lightning impulses according to this application; Figure 13 This is a schematic diagram of the surface field strength of insulators at different through-hole positions under DC superimposed lightning strikes of the same polarity, as described in this application. Detailed Implementation

[0022] In the following, specific embodiments of this application will be described in detail with reference to the accompanying drawings. Based on these detailed descriptions, those skilled in the art will be able to clearly understand and implement this application. Without departing from the principles of this application, features from various embodiments can be combined to obtain new implementations, or certain features from some embodiments can be substituted to obtain other preferred implementations.

[0023] See Figures 1-13This application provides a design method for a lightweight DC GIS arc transition type vented basin insulator. The method includes the following steps: establishing a geometric model of a ±550kV DC GIS vented basin insulator and importing the geometric model into finite element simulation software; setting a temperature physical field, an electric field physical field, and a stress calculation physical field in the finite element simulation software according to the actual heat source distribution and heat transfer conditions inside the pipeline; calculating the temperature distribution of the insulator with through holes based on the temperature physical field; and calculating the temperature distribution of the insulator with through holes and the electric field physical field based on the electric field physical field. The surface charge and electric field distribution along the surface of the insulator with through holes are analyzed to determine whether they meet the insulation requirements. If not, the size, shape, and position of the through holes are adjusted, and the calculation is repeated. If the insulation requirements are met, stress verification is performed on the insulator with through holes under transportation and vertical pipeline installation conditions to determine whether the stress requirements are met. If not, the size, shape, and position of the through holes are adjusted, and the above steps are repeated. By continuously optimizing the through hole structure, the design of the ±550kV DC GIS vented basin insulator is completed. The finite element simulation software includes a temperature calculation module, an electric field calculation module, and a stress calculation module connected in sequence.

[0024] Specifically, a geometric model of a ±550kV DC GIS ventilated basin insulator was established using SolidWorks and imported into the Comsol finite element simulation software. Based on the actual heat source distribution and heat transfer conditions within the pipeline, laminar flow, solid-fluid heat transfer, surface-to-surface radiation, laminar and solid, and fluid heat transfer physical fields were set up in the Comsol finite element simulation software. Based on the conductivity model under DC voltage, rare-material transport, electrostatic, ordinary differential, and differential-algebraic equation physical fields (domain and boundary) were set up, with three mechanisms considered for surface charge accumulation. The physical field used for stress calculation was the solid mechanics physical field. After obtaining the insulator temperature distribution through the temperature calculation module, the electric field calculation module was used to calculate the surface field strength of the insulator under DC steady-state conditions and under DC superimposed lightning impacts of different polarities to determine if the insulation requirements were met. If not, the size, shape, and position of the through-holes were adjusted, and the calculation was repeated. If the insulation requirements are met, the stress is checked using the stress calculation module under both the transportation and vertical installation conditions of the pipeline, and it is determined whether the stress requirements are met. If not, the size, shape, and position of the through hole are adjusted, and the above steps are repeated.

[0025] The design of the insulator was completed by continuously optimizing the through-hole structure.

[0026] 1) After drawing the geometric model of the ±550kV DC GIS vented basin insulator in SolidWorks, import it into the COMSOL finite element simulation software. The simulation model's geometric structure consists of a ±550kV DC GIS vented basin insulator, a grounding shell, a high-voltage conductor, and insulating gas. The specific composition and dimensions are as follows: Figures 2-3 As shown. The four through holes are evenly distributed. To simplify the calculation of the 3D model, a quarter of the model is used for calculation, and periodic conditions are added to the boundaries to ensure calculation accuracy. The high-voltage conductor, shield, and grounding shell are all made of aluminum alloy. The ±550kV DC GIS vented basin insulator is made of epoxy alumina composite material, and the insulating gas is pure SF6 at a pressure of 5 atmospheres. The included angle between the two through holes on the insulator is 90°. A shield is installed at the connection between the high-voltage conductor and the insulator to weaken the electric field strength at the junction of the insulator, insulating gas, and high-voltage conductor, preventing discharge.

[0027] 2) The heat transfer module uses laminar flow physics, solid-fluid heat transfer physics, and surface-to-surface radiation physics. The laminar and solid physics and fluid heat transfer physics are coupled through non-isothermal heat transfer multi-physics coupling. Since the heat source P of the central guide rod is difficult to estimate accurately, the heat generation power P of the guide rod is replaced with a Dirichlet boundary condition of a specific temperature in the simulation model. Temperature calculations are performed on this geometric model to obtain the temperature distribution of the ±550kV DC GIS vented basin insulator.

[0028] 3) Electrical performance: The physical fields used based on the conductivity model and surface charge accumulation mechanism are the rare matter transport physical field, electrostatic physical field, ordinary differential physical field, and differential algebraic equation physical field (domain and boundary). The changes in space charge inside the insulator are calculated using the domain ordinary differential physical field and differential algebraic equation physical field, while the changes in surface charge of the insulator are calculated using the boundary ordinary differential physical field and differential algebraic equation physical field. The surface charge considers three mechanisms: insulator volume current accumulation (solid side), insulator surface current accumulation (along the surface), and insulating gas volume current accumulation (gas side). To more accurately describe the current density on the gas side, the transport equation of charged particles is used to construct the ion flow field in the gas under a DC electric field in the rare matter transport physical field. When meshing, a free triangular mesh is created on the boundary of the insulator surface for refinement, which can improve the calculation speed while ensuring the accuracy of the simulation results. Since the temperature field distribution within the GIS is only related to the Joule heating in the conductor and is independent of the electric field distribution in the insulating gas and insulator, and the time for surface charge accumulation to reach saturation is much longer than the time for the temperature to reach a steady state. Therefore, the temperature and electric field calculations are decoupled, and the temperature value calculated in step ② is passed as an invariant into the electric field calculation module. The rare matter transport physical field is used to construct the ion flow field in the gas, and as the source of surface charge on the gas side, it is unidirectionally coupled with the boundary ordinary differential equation. The charge density and electric field strength are connected through the Poisson equation. Therefore, the boundary ordinary differential equation, rare matter transport, and domain differential equation are all bidirectionally coupled with the electrostatic field, and the specific coupling relationship is as follows: Figure 4 As shown. Calculate the surface electric field strength of the insulator under DC steady-state conditions and under DC superimposed lightning impulses of different polarities, and determine whether it meets the insulation performance requirements (determine whether the tangential electric field strength on the insulator surface under DC superimposed lightning impulses is greater than 12kV / mm. This requirement is not applied under DC steady-state conditions). If it does not meet the requirements, adjust the size, shape, and position of the through-hole, and repeat step ②.

[0029] 4) The physical field used for mechanical properties is solid mechanics. After ensuring the insulator meets the above insulation performance requirements, the stress on the insulator is calculated under transportation conditions and when the pipeline is installed vertically (insulators generally have two installation methods; the stress under these two conditions is mainly considered). Specific calculation methods are as follows: Figure 9 As shown, (a) a 6 times gravitational acceleration is directly applied to the guide rod in the simulation, and (b) a 30kN force is applied to the guide rod. It is then determined whether the mechanical performance is met (the maximum stress on the insulator cannot exceed 70MPa, and the maximum stress at the insulator-metal insert cannot exceed 20MPa). If not, step ② is repeated.

[0030] The high-voltage conductor has a radius of 75 mm, the insulator has a radius of 332 mm, the pipe has a radius of 350.5 mm, the outer shell has a thickness of 8 mm, the metal insert has a length of 95 mm, the shield has a length of 170 mm, the shield has a maximum radius of 97.685 mm, the inner shield ring of the insulator has a radius of 7 mm, and the distance from the center of the shield ring to the grounding flange is 64.5 mm.

[0031] Figure 2 The four through holes are evenly distributed. To reduce the computational burden of the 3D model, the entire model is simplified to 1 / 4. The simulation results of surface charge and electric field distribution along the surface shown below represent only 1 / 4 of the entire insulator. Based on the electric field distribution on the insulator surface under different shapes, it can be found that a radially distributed ellipse can effectively reduce the maximum electric field on the insulator surface. Therefore, during the iterative optimization process, the shape of the through-hole should be made as radially distributed as possible.

[0032] Shape, size, and position are important factors affecting the surface electric field of an insulator. In fact, these three quantities are not independent; they influence each other. However, the influence of size and shape on the surface electric field is relatively singular, while the influence of position is not monotonic. Therefore, in the design of through-holes, the size and shape are determined first, and then the position of the through-hole is continuously adjusted to see if it meets the requirements. If changing the position cannot meet the requirements, then the size or shape is adjusted.

[0033] Figure 10 The effect of size on the electric field on the insulator surface is shown. The maximum electric field strength on the insulator surface decreases monotonically as the size of the through hole decreases.

[0034] Figure 11 To understand the influence of shape on the electric field on the surface of insulators, the maximum electric field strength of through holes of different shapes is dominated by the normal electric field strength. The radially distributed double-circular-arc transition type through holes can effectively reduce the number of electric field lines passing through and suppress the normal electric field strength at the through holes, thereby minimizing the combined electric field strength.

[0035] Figure 12 and 13 To explain the effect of location on the electric field on the surface of the insulator, when the insulator is subjected to a DC superimposed lightning strike of opposite polarity, the maximum electric field strength at the through-hole exhibits two dominant processes. When the through-hole is far from the high-voltage conductor, the combined electric field strength is dominated by the tangential field strength. As it approaches the conductor, the normal electric field strength at the through-hole rises rapidly and dominates the combined electric field strength.

[0036] When an insulator is subjected to a DC superimposed lightning strike of the same polarity, the maximum electric field strength at the through hole is dominated by the normal field strength. Moreover, the normal field strength does not show a monotonic trend like the tangential field strength. Instead, as the through hole moves away from the high-voltage conductor, the normal field strength first decreases and then increases. When the through hole is close enough to the grounding flange, the normal field strength decreases again.

[0037] Figure 5 The through-hole is a double-arc transition type, consisting of an arc with a radius of 33mm and an arc with a radius of 12mm, respectively. The distances from these arcs to the center of the through-hole are 16mm and 13.3mm, respectively. The distance from the center of the shorter arc on the side closer to the high-voltage guide rod to the center of the guide rod is 210.33mm.

[0038] Figure 6 The change of the electric field strength distribution along the surface of the insulator with time after applying a voltage of 550kV is shown. The maximum electric field strength along the surface of the insulator in steady state is 6.160 kV / mm.

[0039] Figure 7 The insulator surface electric field distribution under DC superimposed same polarity lightning impulse is shown. The maximum combined electric field strength is 11.589 kV / mm and the maximum tangential electric field strength is 8.725 kV / mm, which meets the requirement that the tangential electric field strength of the insulator is less than 12 kV / mm under 0.4 MPa SF6.

[0040] Figure 8 The insulator surface electric field distribution under DC superimposed opposite polarity lightning impulse is shown. The maximum combined electric field strength is 11.379 kV / mm and the maximum tangential electric field strength is 11.350 kV / mm, which meets the requirement that the tangential electric field strength of 0.4 MPa SF6 insulator is less than 12 kV / mm.

[0041] Figure 9 To illustrate the stress on the insulator under different conditions, a downward vertical acceleration of 6g is applied to the guide rod during transportation, while a force of 30 kN is applied to the guide rod in the vertical pipeline condition. The maximum stress values ​​of the insulator under these two conditions are 6.40 MPa and 8.02 MPa, respectively, both less than the standard of 70 MPa. The maximum stress values ​​of the insulator-metal insert under these two conditions are 15.08 MPa and 8.81 MPa, respectively, both less than the standard of 20 MPa.

[0042] Simulation results verified that the lightweight ±550kV DC GIS arc transition type ventilated basin insulator designed in this application meets the insulation and mechanical performance requirements. The maximum combined electric field strength along the insulator surface under DC steady-state conditions is 6.160 kV / mm. Under DC superimposed same-polarity lightning impulses, the maximum tangential electric field strength along the insulator surface is 8.725 kV / mm, less than the standard of 12 kV / mm; under DC superimposed opposite-polarity lightning impulses, the maximum tangential electric field strength along the insulator surface is 11.350 kV / mm, less than the standard of 12 kV / mm; under transportation and vertical pipeline installation conditions, the maximum surface stress of the insulator is 6.40 MPa and 8.02 MPa, respectively, less than the standard of 70 MPa; the maximum stress of the insulator-metal insert under these two conditions is 15.08 MPa and 8.81 MPa, respectively, less than the standard of 20 MPa. Simulation results are as follows: Figures 6-9 As shown.

[0043] By determining the size, shape, and location of the through-hole, a lightweight ±550kV DC GIS arc transition type vented basin insulator was designed. This allows for the connection of different air chambers within the GIS, reducing manufacturing costs and the overall weight of the GIS. The through-hole shape determined in this invention is applicable not only to the 550kV voltage level but also to other DC voltage levels.

[0044] Although this application has been described above with reference to specific embodiments, those skilled in the art will understand that many modifications can be made to the configurations and details disclosed in this application within the principles and scope of the disclosure. The scope of protection of this application is determined by the appended claims, and the claims are intended to cover all modifications included in the literal meaning or scope of equivalents of the technical features in the claims.

Claims

1. A design method for a lightweight DC GIS arc transition type ventilated basin insulator, characterized in that: The method includes the following steps: establishing a geometric model of a ±550kV DC GIS vented basin insulator and importing the geometric model into finite element simulation software; setting a temperature physical field, an electric field physical field, and a stress calculation physical field in the finite element simulation software based on the actual heat source distribution and heat transfer conditions inside the pipeline; calculating the temperature distribution of the ±550kV DC GIS vented basin insulator based on the temperature physical field; calculating the surface charge and surface electric field distribution of the ±550kV DC GIS vented basin insulator based on the temperature distribution and the electric field physical field; determining whether the surface charge and surface electric field distribution meet the insulation requirements; if not, adjusting the size, shape, and position of the through hole and recalculating; if the insulation requirements are met, performing stress verification on the ±550kV DC GIS vented basin insulator under transportation and vertical pipeline installation conditions, and determining whether the mechanical requirements are met; if not, adjusting the size, shape, and position of the through hole and repeating the above steps; and completing the design of the ±550kV DC GIS vented basin insulator by continuously optimizing the through hole structure.

2. The lightweight DC GIS arc transition type ventilated basin insulator design method as described in claim 1, characterized in that: The finite element simulation software includes a temperature calculation module, an electric field calculation module, and a stress calculation module connected in sequence.

3. The lightweight DC GIS arc transition type ventilated basin insulator design method as described in claim 2, characterized in that: The temperature physical field consists of a laminar flow physical field, a solid-fluid heat transfer physical field, and a surface-to-surface radiation physical field. The laminar flow physical field and the solid-fluid heat transfer physical field are coupled through non-isothermal heat transfer multi-physics field coupling.

4. The lightweight DC GIS arc transition type ventilated basin insulator design method as described in claim 3, characterized in that: In the simulation model, the power of the conductor rod heating is replaced by the Dirichlet boundary condition of temperature. The temperature calculation module is used to calculate the temperature of the geometric model to obtain the temperature distribution of the ±550kV DC GIS vented basin insulator.

5. The lightweight DC GIS arc transition type ventilated basin insulator design method as described in claim 4, characterized in that: The temperature values ​​in the temperature distribution are input as invariants into the electric field calculation module to calculate the surface electric field distribution of the insulator under DC steady state and DC superimposed lightning impacts of different polarities.

6. The design method for lightweight DC GIS arc transition type ventilated basin insulator as described in claim 5, characterized in that: The electric field physical field is a physical field used based on the conductivity model and the surface charge accumulation mechanism. The electric field physical field is a rare matter transport physical field, an electrostatic physical field, a domain ordinary differential physical field, a boundary ordinary differential physical field, a domain differential algebraic equation physical field, and a boundary differential algebraic equation physical field.

7. The lightweight DC GIS arc transition type ventilated basin insulator design method as described in claim 6, characterized in that: The changes in internal space charge of the insulator are calculated using the domain ordinary differential physical field and the domain differential algebraic equation physical field in the electric field calculation module, and the changes in surface charge of the insulator are calculated using the boundary ordinary differential physical field and the boundary differential algebraic equation physical field in the electric field calculation module.

8. The design method for lightweight DC GIS arc transition type ventilated basin insulator as described in claim 7, characterized in that: The surface charge takes into account three mechanisms: insulator volume current accumulation, insulator surface current accumulation, and insulating gas volume current accumulation.

9. The lightweight DC GIS arc transition type ventilated basin insulator as described in claim 8, characterized in that: In the physical field of rare matter transport, the transport equation of charged particles is used to construct the ion flow field in the gas under the DC electric field; when dividing the grid, a free triangular grid is created on the boundary of the insulator surface for refinement.

10. The design method for a lightweight DC GIS arc transition type ventilated basin insulator as described in any one of claims 1 to 9, characterized in that: The through hole is a double-arc transition type.

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