High-voltage direct-current GIS / GIL basin-type insulator and optimization method, system and equipment thereof

Abstract

The invention belongs to the technical field of direct-current high-voltage GIS insulation, and relates to a basin-type insulator of a high-voltage direct-current GIS / GIL and an optimization method, system and device of the basin-type insulator. Modeling the insulator structure to obtain an insulator structure model, modeling the shielding case to obtain a shielding case structure model, and establishing a multi-physics field coupling model according to the physics field boundary condition and the initial value of the basin-type insulator under the actual working condition in combination with the GIS insulation structure two-dimensional axisymmetric model; and substituting the insulator structure model and the shielding case structure model into a multi-physics field coupling model to solve surface charge distribution and electric field distribution of the basin-type insulator, and selecting an optimal basin-type insulator structure according to the surface charge distribution and electric field distribution of the basin-type insulator. The structure of the basin-type insulator can be optimized, the optimized structure of the basin-type insulator can relieve concentration of local electric stress under the working condition of high-voltage direct current, long-term insulation is guaranteed, reliability of long-term insulation is improved, and safe and stable operation of a direct-current GIS is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of DC high-voltage GIS insulation, and relates to a pot-type insulator of a high-voltage DC GIS / GIL and an optimization method, system and equipment thereof. Background Art

[0002] DC field equipment is an important part of offshore converter stations and onshore converter stations. The higher the DC voltage level, the more space is needed for the power equipment, especially for the air-insulated equipment used for switch operation and system reset in the DC field, such as disconnectors, grounding switches, current and voltage measurement systems, lightning arresters, gas-air bushings and cable connection equipment. Traditional open air-insulated DC field equipment occupies a large space, which limits the development of large-capacity and lightweight offshore platforms. DC gas-insulated switchgear GIS not only helps to reduce the footprint of onshore converter stations, but also helps to reduce the facility investment cost of offshore wind farms with large capacity and far from the shore. Compared with the DC field using air-insulated equipment, the space of the DC field using DC GIS can be reduced by 70% to 95%, and it has higher reliability because the high-voltage components will not be affected by external dust, salty air, rain and snow. Therefore, the research and development of DC GIS is the key to the future development of DC transmission technology.

[0003] The safety and reliability of the insulation system under DC conditions is the key to ensuring the stable operation of GIS. Under DC voltage, due to the long-term action of the unipolar electric field, the charged particles in the insulating gas of the DC GIS and the carriers in the insulating material are gradually transferred to the gas-solid interface under the action of the tangential electric field and the normal electric field of the insulating interface, resulting in significant interfacial charge accumulation on the surface of the insulator, causing distortion of the gas-solid interface electric field, which can easily induce surface flashover of the insulator, seriously affecting the safe and stable operation of the DC GIS. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a pot-type insulator for a high-voltage DC GIS / GIL and an optimization method, system and equipment thereof. The present invention can achieve structural optimization of the pot-type insulator. The optimized pot-type insulator structure can alleviate the concentration of local electrical stress under high-voltage DC working conditions, ensure long-term insulation, improve the reliability of long-term insulation, and help ensure the safe and stable operation of the DC GIS.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention discloses a method for optimizing the structure of a pot-type insulator of a high-voltage direct current GIS / GIL, comprising the following steps:

[0007] The insulator structure is modeled by using the Bernstein quintic equation to obtain an insulator structure model, and the shielding cover is modeled by using a non-uniform rational B-spline curve to obtain a shielding cover structure model;

[0008] A two-dimensional axisymmetric model of the GIS insulation structure is established based on the electromagnetic field and dilute material transfer theory. According to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure.

[0009] The insulator structure model and the shield structure model are substituted into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the pot insulator, and the optimal structure of the pot insulator is selected according to the surface charge distribution and electric field distribution of the pot insulator.

[0010] In a second aspect, the present invention discloses a structural optimization system for a pot-type insulator of a high-voltage DC GIS / GIL, comprising a geometric model building module, a coupling model building module and a structural solution acquisition module connected in sequence, wherein:

[0011] Geometric model building module: used to model the insulator structure using Bernstein quintic equation to obtain the insulator structure model, and to model the shielding cover using non-uniform rational B-spline curve to obtain the shielding cover structure model;

[0012] Coupling model building module: used to establish a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare-matter transfer theory. According to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure.

[0013] Structural solution acquisition module: used to substitute the insulator structure model and the shielding cover structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the pot-type insulator, and select the optimal pot-type insulator structure according to the surface charge distribution and electric field distribution of the pot-type insulator.

[0014] In a third aspect, the present invention discloses an electronic device, comprising: a processor; a memory for storing computer program instructions; and steps for implementing a structural optimization method for pot-type insulators of a high-voltage DC GIS / GIL when executing the computer program.

[0015] In a fourth aspect, the present invention discloses a structure of a pot-type insulator for a high-voltage direct current GIS / GIL, which is obtained by using a structure optimization method for a pot-type insulator for a high-voltage direct current GIS / GIL, and is specifically as follows:

[0016] The structural parameters of the upper surface of the pot insulator are: a2 is 4.40, a3 is 14.99, k is 25.07, and b is -9.93;

[0017] The structural parameters of the lower surface of the pot insulator are: a2 is 10.99, a3 is 14.99, k is 25.52, and b is -9.99;

[0018] The horizontal coordinates of the control points of the shield from the convex side to the concave side of the insulator are 149.85, 104.25, 98.28, and 80.32 respectively;

[0019] The radius of the insulator is 240.56mm.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The method of the present invention uses the Bernstein quintic equation to model the insulator structure to obtain the insulator structure model, and uses the non-uniform rational B-spline curve to model the shielding cover to obtain the shielding cover structure model, which is convenient for realizing accurate and efficient insulator and shielding cover contour control; establishes a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare substance transfer theory, and establishes a multi-physics field coupling model in combination with the two-dimensional axisymmetric model of the GIS insulation structure according to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator; substitutes the insulator structure model and the shielding cover structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the basin insulator, and selects the optimal basin insulator structure according to the surface charge distribution and electric field distribution of the basin insulator. The present invention can realize the structural optimization of the basin insulator, and the optimized basin insulator structure can alleviate the concentration of local electrical stress under the working conditions of high-voltage direct current, ensure long-term insulation, improve the reliability of long-term insulation, and help ensure the safe and stable operation of DC GIS.

[0022] 2. The method of the present invention is based on the solid-side conduction current, the gas-side conduction current and the surface conduction current gas-solid interface charge density, which is beneficial to improving the reliability of the optimized pot-type insulator structure.

[0023] 3. The system of the present invention includes a geometric model building module, a coupling model building module and a structure solution acquisition module connected in sequence, wherein: the geometric model building module is used to use the Bernstein quintic equation to model the insulator structure to obtain the insulator structure model, and use the non-uniform rational B-spline curve to model the shielding cover to obtain the shielding cover structure model; the coupling model building module is used to establish a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare substance transfer theory, and according to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure; the structure solution acquisition module is used to substitute the insulator structure model and the shielding cover structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the basin insulator, and select the optimal basin insulator structure according to the surface charge distribution and electric field distribution of the basin insulator. Each module cooperates with each other, and the present invention can realize the structural optimization of the basin insulator. The optimized basin insulator structure can alleviate the concentration of local electrical stress under the working conditions of high-voltage direct current, ensure long-term insulation, improve the reliability of long-term insulation, and help ensure the safe and stable operation of DC GIS.

[0024] 4. The electronic equipment of the present invention can also achieve structural optimization of the pot-type insulator. The optimized pot-type insulator structure can alleviate the concentration of local electrical stress under high-voltage DC working conditions, ensure long-term insulation, improve the reliability of long-term insulation, and help ensure the safe and stable operation of DC GIS.

[0025] 5. The structure of the pot-type insulator of the high-voltage DC GIS / GIL of the present invention: the structural parameters of the upper surface of the pot-type insulator are: a2 is 4.40, a3 is 14.99, k is 25.07, and b is -9.93; the structural parameters of the lower surface of the pot-type insulator are: a2 is 10.99, a3 is 14.99, k is 25.52, and b is -9.99; the horizontal coordinates of the control points of the shielding cover from the convex side to the concave side of the insulator are 149.85, 104.25, 98.28, and 80.32 respectively; the radius of the insulator is 2 40.56mm. Compared with the pot-type insulator of AC GIS / GIL, the maximum charge density of the upper and lower surfaces of the insulator decreased by 96.34% and 73.32% respectively, and the normal electric field strength decreased by 66.96% and 40.33% respectively, while the tangential electric field strength of the upper and lower surfaces was 3.50kV / mm and 3.25kV / mm respectively, which met the optimization design standards. Therefore, this insulation structure greatly reduces the charge accumulation on the insulator surface and greatly improves the insulation stability of the insulator under high voltage DC conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of modeling the insulator and the shielding cover of the present invention;

[0027] Figure 2 The electric field mode distribution diagram of the multi-physics field coupling model of the present invention;

[0028] Figure 3 This is a comparison diagram of the distribution of charges on the surface of the insulator before and after the optimization of the present invention;

[0029] Figure 4 This is a comparison diagram of the distribution of the normal electric field on the surface of the insulator before and after the optimization of the present invention;

[0030] Figure 5 This is a comparison diagram of the distribution of the tangential electric field on the surface of the insulator before and after the optimization of the present invention;

[0031] Figure 6 is a flow chart of the method of the present invention;

[0032] Figure 7 It is a system module diagram of the present invention;

[0033] Figure 8 It is a three-dimensional model diagram of the present invention.

[0034] Among them, 1. Insulator; 2. Shielding cover. DETAILED DESCRIPTION

[0035] 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 should fall within the scope of protection of the present invention.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data 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. 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.

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0038] See also Figure 6The present invention discloses a method for optimizing the structure of a pot-type insulator of a high-voltage direct current GIS / GIL, comprising the following steps:

[0039] S1. The insulator structure is modeled by using the Bernstein quintic equation to obtain an insulator structure model, and the shielding cover is modeled by using a non-uniform rational B-spline curve to obtain a shielding cover structure model;

[0040] Preferably, the insulator structure model formula is as follows:

[0041] L(r)=k[(1-r) 5 +5(1-r) 4 r+a2(1-r) 3 r 2 +a3(1-r) 2 r 3 ]+b

[0042] Among them, L(r) is the Bernstein quintic polynomial about the coordinate r, a2, a3, k and b are decision variables that control the change of the outer contour of the insulator. Specifically, a2 and a3 are the contours of the two middle points of the control curve, k is the slope of the control curve, and b is the longitudinal position of the control curve.

[0043] Preferably, a non-uniform rational B-spline curve is used to model the shielding cover to obtain a shielding cover structure model, as follows:

[0044] The shielding cover is modeled by using non-uniform rational B-spline curves to obtain a shielding cover structure model;

[0045] By changing the coordinates of the control points, the shape of the spline curve is changed, thereby changing the outline of the shielding cover structure model, see Figure 1 Schematic diagram of modeling the insulator and shield.

[0046] S2. Establish a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and dilute material transfer theory. According to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure.

[0047] S3. Substitute the insulator structure model and the shield structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the pot insulator. According to the surface charge distribution and electric field distribution of the pot insulator, the optimal pot insulator structure is selected. Figure 2 This is the electric field mode distribution diagram of the multi-physics field coupling model of the present invention, see Figure 3 This is a comparison diagram of the surface charge distribution of the insulator before and after the optimization of the present invention, see Figure 4 This is a comparison diagram of the distribution of the normal electric field on the insulator surface before and after the optimization of the present invention, see Figure 5This is a comparison diagram of the distribution of the tangential electric field on the insulator surface before and after the optimization of the present invention.

[0048] Preferably, the surface charge distribution of the pot-type insulator includes solving the gas-solid interface charge density, and the gas-solid interface charge density formula is as follows:

[0049]

[0050] in, is the charge density at the gas-solid interface, J V is the solid side conduction current, J G is the gas side conduction current density, γ S is the surface resistivity, E t is the tangential electric field strength.

[0051] Preferably, the calculation formula of the solid side conduction current is as follows:

[0052]

[0053] Among them, J V is the solid side conduction current, D is the electric flux density, E is the normal electric field strength of the pot insulator, γ V is the volume conductivity.

[0054] Preferably, the calculation formula of the gas side conduction current density is as follows:

[0055]

[0056] Among them, J G is the gas side conduction current density, D is the electric flux density, E is the normal electric field strength of the pot insulator, e is the elementary charge, n + is the positive ion density, n - is the negative ion density, b + is the positive ion mobility, b - is the negative ion mobility, D + is the positive ion diffusion coefficient, D - is the negative ion diffusion coefficient.

[0057] Preferably, the optimal structure of the pot-type insulator is selected according to the surface charge distribution and electric field distribution of the pot-type insulator as follows:

[0058] The surface charge distribution of the optimal pot-type insulator structure is: the charge is less than 20μC / m2;

[0059] The electric field distribution is as follows: the normal electric field is less than 1 kV / mm, and the tangential electric field is less than 3.5 kV / mm.

[0060] See also Figure 6In another feasible embodiment of the present invention, the following is adaptively modified according to the situation. The insulator structure is modeled using the Bernstein quintic equation to obtain an insulator structure model, and the shielding cover is modeled using a non-uniform rational B-spline curve to obtain a shielding cover structure model, which can achieve accurate and efficient contour control of the insulator and the shielding cover; a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare earth material transfer theory is established, and a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure according to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator; the insulator structure model and the shielding cover structure model are substituted into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the basin insulator, and the optimal basin insulator structure is selected according to the surface charge distribution and electric field distribution of the basin insulator. The present invention can achieve structural optimization of the basin insulator, and the optimized basin insulator structure can alleviate the concentration of local electrical stress under high-voltage DC working conditions, ensure long-term insulation, improve the reliability of long-term insulation, and help ensure the safe and stable operation of DC GIS. See. Figure 8 , is a schematic diagram of the structure of the optimized insulator 1 and the shielding cover 2. The shielding covers 2 on both sides of the insulator are asymmetric, which is an asymmetric shielding cover structure on both sides.

[0061] Embodiment 1:

[0062] See also Figure 6 This embodiment discloses a method for optimizing the structure of a pot-type insulator of a high-voltage direct current GIS / GIL, comprising the following steps:

[0063] S1. Use Bernstein's quintic equation to model the insulator structure, where a2, a3, k and b are all control parameters of the profile. By controlling these parameters, the shape of the polynomial curve can be changed, thereby achieving the purpose of changing the insulator profile;

[0064] L(r)=k[(1-r) 5 +5(1-r) 4 r+a2(1-r) 3 r 2 +a3(1-r) 2 r 3 ]+b

[0065] Among them, L(r) is the Bernstein quintic polynomial about the coordinate r, a2, a3, k and b are the decision variables that control the change of the outer contour of the insulator, a2 and a3 control the contours of the two points in the middle of the curve, k controls the slope of the curve, and b controls the longitudinal position of the curve. The upper and lower contours of the insulator are modeled separately using two Bernstein curves.

[0066] S2. Using non-uniform rational B-spline curves to model the shielding cover, and changing the shape of the spline curve by changing the coordinates of the control points, thereby achieving the purpose of controlling the outline of the shielding cover;

[0067] S3. A two-dimensional axisymmetric model of the GIS insulation structure based on electromagnetic field and dilute species transfer theory is established in COMSOL software. The boundary conditions and initial values ​​of each physical field are set according to the actual working conditions. A multi-physical field coupling model is established to solve the charge distribution and electric field distribution on the surface of the GIS insulation structure. The physical fields include electromagnetic field, thermal field, and dilute species transfer field. The specific simulation settings are as follows:

[0068] The charge accumulation at the gas-solid interface of the pot-type insulator under DC voltage is the solid side conduction current J v , gas side conduction current J G The conduction current J along the surface of the basin insulator s As a result of comprehensive effects, a charge accumulation model at the gas-solid interface of pot-type insulators was established using the finite element simulation method based on the three conduction mechanisms.

[0069] The solid side conduction current JV of the pot insulator is composed of displacement current and conduction current:

[0070]

[0071] Where D is the electric flux density; E is the normal electric field strength of the pot insulator; γ V is the volume conductivity, and the present invention selects 1.2×10-14 S / m based on the measurement result of the volume resistivity of the pot-type insulator.

[0072] The gas side conduction of the basin insulator includes the migration and diffusion of gas particles, the generation and recombination of ion pairs, and the positive and negative ion densities n+ and n- in the gas are solved by the following charge drift diffusion equation:

[0073]

[0074] Where n IP is the ion pair generation rate in the gas, which is taken as 30IP (cm2·s) in the present invention, k r is the composite coefficient, taking 1.74×10-7cm 3 / s; b+ and b- are the positive and negative ion mobility, respectively, taking 0.048cm 2 / (V·s);D + With D - are the diffusion coefficients of positive and negative ions, respectively.

[0075] According to the Einstein equation, the diffusion coefficients of positive and negative ions can be calculated as follows:

[0076]

[0077] In the formula, k B is the Boltzmann constant, 1.380649×10-23J / K; T is the gas temperature, which is 293K in the present invention; e is the elementary charge, which is 1.6×10-19C. According to the potential distribution The electric field distribution in the gas can be calculated:

[0078]

[0079] Where E is the electric field distribution in the gas;

[0080] Potential The relationship with the space charge density ρ is described by Poisson's equation:

[0081]

[0082] in, is the Laplace operator of the electric potential, ε is the dielectric constant, n + is the positive ion density, n - is the negative ion density, e is the elementary charge;

[0083] Gas side conduction current density J G Calculated by the following formula:

[0084]

[0085] Among them, J G is the gas side conduction current density, D is the electric flux density, E is the normal electric field strength of the pot insulator, e is the elementary charge, n + is the positive ion density, n - is the negative ion density, b + is the positive ion mobility, b - is the negative ion mobility, D + is the positive ion diffusion coefficient, D - is the negative ion diffusion coefficient.

[0086] Conducted current J along the surface of the pot insulator s Depends on the surface resistivity γ S and the tangential electric field strength E t The charge density at the gas-solid interface can be calculated by the following formula:

[0087]

[0088] In the formula, is the charge density at the gas-solid interface, J V is the solid side conduction current, J G is the gas side conduction current density, γS is the surface resistivity, E t is the tangential electric field strength.

[0089] The initial charge density can be calculated by the following equation:

[0090]

[0091] Among them, n + (t0) is the initial charge density, n - (t0) is the initial negative ion density, n IP is the ion pair generation rate in the gas, k r is the composite coefficient;

[0092] The boundary conditions can be set to Dirichlet boundary conditions, with the high voltage electrode voltage of 550 kV and the ground terminal voltage of 0.

[0093] S4, by continuously changing the control parameters a2, a3, k and b of the insulation structure, and performing the finite element simulation calculation shown in S3 on the changed structure, the corresponding charge distribution and electric field distribution are obtained, and the insulation structure with the best charge and electric field distribution is selected from the models with different structural parameters as the final structure;

[0094] The selection criteria are: charge less than 20μC / m2, normal electric field less than 1kV / mm, and tangential electric field less than 3.5kV / mm.

[0095] S5. By changing the parameters, a shallow arc insulator structure and an asymmetric shielding cover structure on both sides are finally obtained. Under this structure, the charge density on the surface of the insulator is reduced by at least 70%, while the electric field distribution still meets the requirements.

[0096] See also Figure 7 Based on the above method, the present invention discloses a structural optimization system for a pot-type insulator of a high-voltage DC GIS / GIL, comprising a geometric model building module, a coupling model building module and a structural solution acquisition module connected in sequence, wherein:

[0097] Geometric model building module: used to model the insulator structure using Bernstein quintic equation to obtain the insulator structure model, and to model the shielding cover using non-uniform rational B-spline curve to obtain the shielding cover structure model;

[0098] Coupling model building module: used to establish a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare-matter transfer theory. According to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure.

[0099] Structural solution acquisition module: used to substitute the insulator structure model and the shielding cover structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the pot-type insulator, and select the optimal pot-type insulator structure according to the surface charge distribution and electric field distribution of the pot-type insulator.

[0100] See also Figure 7 In another feasible embodiment of the present invention, the following is adaptively modified according to the situation. It includes a geometric model construction module, a coupling model construction module and a structure solution acquisition module connected in sequence, wherein: the geometric model construction module is used to use the Bernstein quintic equation to model the insulator structure to obtain the insulator structure model, and use the non-uniform rational B-spline curve to model the shielding cover to obtain the shielding cover structure model; the coupling model construction module is used to establish a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare substance transfer theory, and according to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, the multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure; the structure solution acquisition module is used to substitute the insulator structure model and the shielding cover structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the basin insulator, and select the optimal basin insulator structure according to the surface charge distribution and electric field distribution of the basin insulator. Each module cooperates with each other, and the present invention can realize the structural optimization of the basin insulator. The optimized basin insulator structure can ensure long-term insulation under the working conditions of high-voltage direct current, improve the reliability of long-term insulation, and help to ensure the safe and stable operation of DC GIS.

[0101] An electronic device comprises: a processor; a memory for storing computer program instructions; and steps for implementing a method for structural optimization of a pot-type insulator of a high-voltage direct current GIS / GIL when executing the computer program.

[0102] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0103] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0104] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0105] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0106] Based on the above method, the present invention discloses a structure of a pot-type insulator for a high-voltage direct current GIS / GIL, which is obtained by using a structure optimization method for a pot-type insulator for a high-voltage direct current GIS / GIL, as follows:

[0107] The structural parameters of the upper surface of the pot insulator are: a2 is 4.40, a3 is 14.99, k is 25.07, and b is -9.93;

[0108] The structural parameters of the lower surface of the pot insulator are: a2 is 10.99, a3 is 14.99, k is 25.52, and b is -9.99;

[0109] The horizontal coordinates of the control points of the shield from the convex side to the concave side of the insulator are 149.85, 104.25, 98.28, and 80.32 respectively;

[0110] The radius of the insulator is 240.56mm.

[0111] The above structure of the present invention can regulate the electric field distribution of the surface charge of the pot-type insulator under DC voltage, alleviate the concentration of local electric stress, and provide a shallow arc insulator structure suitable for DC GIS / GIL pot-type insulators and an asymmetric structure of a shielding cover connected to the pot-type insulator.

[0112] Compared with the pot-type insulator of AC GIS / GIL, the maximum charge density of the charges on the upper and lower surfaces of the pot-type insulator of the present invention is reduced by 96.34% and 73.32% respectively, and the normal electric field strength is reduced by 66.96% and 40.33% respectively, while the tangential electric field strength of the upper and lower surfaces is 3.50 kV / mm and 3.25 kV / mm respectively, which meets the optimization design standard. Therefore, the charge accumulation on the surface of the insulator is greatly reduced under the insulation structure, and the insulation stability of the insulator under high voltage DC conditions is greatly improved.

[0113] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for optimizing the structure of a pot-type insulator of a high-voltage direct current GIS / GIL, characterized in that: The following steps are involved: The insulator structure is modeled by using the Bernstein quintic equation to obtain an insulator structure model, and the shielding cover is modeled by using a non-uniform rational B-spline curve to obtain a shielding cover structure model; A two-dimensional axisymmetric model of the GIS insulation structure is established based on the electromagnetic field and dilute material transfer theory. According to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure. The insulator structure model and the shield structure model are substituted into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the pot insulator, and the optimal structure of the pot insulator is selected according to the surface charge distribution and electric field distribution of the pot insulator.

2. The structural optimization method of the pot-type insulator of the high-voltage direct current GIS / GIL according to claim 1 is characterized in that: The insulator structure model formula is as follows: L(r)=k[(1-r) 5 +5(1-r) 4 r+a2(1-r) 3 r 2 +a3(1-r) 2 r 3 ]+b Among them, L(r) is the Bernstein quintic polynomial about the coordinate r, a2, a3, k and b are decision variables that control the change of the outer contour of the insulator. Specifically, a2 and a3 are the contours of the two middle points of the control curve, k is the slope of the control curve, and b is the longitudinal position of the control curve.

3. The structural optimization method for pot-type insulators of high-voltage direct current GIS / GIL according to claim 1, characterized in that: The shielding cover structure model is obtained by using the non-uniform rational B-spline curve to model the shielding cover, as follows: The shielding cover is modeled by using non-uniform rational B-spline curves to obtain a shielding cover structure model; The shape of the spline curve is changed by changing the coordinates of the control points, thereby changing the contour of the shielding cover structure model.

4. The structural optimization method of the pot-type insulator of the high-voltage direct current GIS / GIL according to claim 1 is characterized in that: The surface charge distribution of the pot-type insulator includes solving the gas-solid interface charge density, and the gas-solid interface charge density formula is as follows: in, is the charge density at the gas-solid interface, J V is the solid side conduction current, J G is the gas side conduction current density, γ S is the surface resistivity, E t is the tangential electric field strength.

5. The structural optimization method of the pot-type insulator of the high-voltage direct current GIS / GIL according to claim 4 is characterized in that: The calculation formula of the solid side conduction current is as follows: Among them, J V is the solid side conduction current, D is the electric flux density, E is the normal electric field strength of the pot insulator, γ V is the volume conductivity.

6. The method for structural optimization of pot-type insulators of high-voltage direct current GIS / GIL according to claim 4, characterized in that: The calculation formula of the gas side conduction current density is as follows: Among them, J G is the gas side conduction current density, D is the electric flux density, E is the normal electric field strength of the pot insulator, e is the elementary charge, n + is the positive ion density, n - is the negative ion density, b + is the positive ion mobility, b - is the negative ion mobility, D + is the positive ion diffusion coefficient, D - is the negative ion diffusion coefficient.

7. The method for structural optimization of pot-type insulators of high-voltage direct current GIS / GIL according to claim 1, characterized in that: The structure of selecting the optimal pot-type insulator according to the surface charge distribution and electric field distribution of the pot-type insulator is specifically as follows: The surface charge distribution of the optimal pot-type insulator structure is: the charge is less than 20μC / m2; The electric field distribution is: the normal electric field is less than 1kV / mm, and the tangential electric field is less than 3.5kV / mm.

8. A structural optimization system for pot-type insulators of a high-voltage DC GIS / GIL for implementing the method described in any one of claims 1 to 7, characterized in that: It includes a geometric model building module, a coupling model building module and a structure solution acquisition module which are connected in sequence, wherein: Geometric model building module: used to model the insulator structure using Bernstein quintic equation to obtain the insulator structure model, and to model the shielding cover using non-uniform rational B-spline curve to obtain the shielding cover structure model; Coupling model building module: used to establish a two-dimensional axisymmetric model of the GIS insulation structure based on the electromagnetic field and rare-matter transfer theory. According to the physical field boundary conditions and initial values ​​under the actual working conditions of the basin insulator, a multi-physics field coupling model is established in combination with the two-dimensional axisymmetric model of the GIS insulation structure. Structural solution acquisition module: used to substitute the insulator structure model and the shielding cover structure model into the multi-physics field coupling model to solve the surface charge distribution and electric field distribution of the pot-type insulator, and select the optimal pot-type insulator structure according to the surface charge distribution and electric field distribution of the pot-type insulator.

9. An electronic device, comprising: processor; A memory for storing computer program instructions; characterized in that it is used to implement the steps of the structural optimization method of the pot-type insulator of the high-voltage DC GIS / GIL as described in any one of claims 1 to 7 when executing the computer program.

10. A structure of a pot-type insulator for a high-voltage direct current GIS / GIL, obtained by using the structure optimization method for a pot-type insulator for a high-voltage direct current GIS / GIL according to any one of claims 1 to 7, characterized in that: The details are as follows: The structural parameters of the upper surface of the pot insulator are: a2 is 4.40, a3 is 14.99, k is 25.07, and b is -9.93; The structural parameters of the lower surface of the pot insulator are: a2 is 10.99, a3 is 14.99, k is 25.52, and b is -9.99; The horizontal coordinates of the control points of the shield from the convex side to the concave side of the insulator are 149.85, 104.25, 98.28, and 80.32 respectively; The radius of the insulator is 240.56mm.

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