A transformer three-dimensional winding structure modeling method suitable for finite element simulation

Abstract

The application discloses a transformer three-dimensional winding structure modeling method suitable for finite element simulation, and relates to the technical field of power transformer simulation calculation. The application can improve the modeling efficiency under the premise of ensuring the model precision, provides reliable technical support for the design and simulation of the transformer winding, and is suitable for the research and design of new transformers, and can be applied to the performance evaluation and fault analysis of existing transformers, thereby improving the operation reliability and safety of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of power transformer simulation calculation, and in particular to a transformer three-dimensional winding structure modeling method suitable for finite element simulation. Background Art

[0002] In recent years, transformers have played a vital role in power systems, and their performance is directly related to the stability and safety of power systems. As the core component of the transformer, the structural design and performance of the transformer winding have a significant impact on the overall performance of the transformer. In practical applications, the three-dimensional structure of the transformer winding is complex, involving multiple conductors, insulation materials, and cooling channels, which makes the establishment of its physical model and simulation calculations extremely complex. Traditional transformer winding design methods mainly rely on experience and simplified two-dimensional analysis, which cannot accurately reflect the actual working state and stress distribution of the winding.

[0003] The introduction of finite element simulation technology has provided a new approach to solving this problem. Finite element simulation can numerically analyze the electromagnetic, temperature, and stress distributions of transformer windings under different operating conditions, providing a theoretical basis for winding design and optimization. However, due to the structural complexity of transformer windings, constructing an accurate and effective three-dimensional model has become a key challenge in finite element simulation applications.

[0004] Therefore, a new solution to the above problems needs to be proposed. Summary of the Invention

[0005] The purpose of the present invention is to provide a transformer three-dimensional winding structure modeling method suitable for finite element simulation, aiming to solve the problems of complex transformer winding structure, difficult modeling, and insufficient simulation accuracy, so as to solve the technical problems raised in the background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a transformer three-dimensional winding structure modeling method suitable for finite element simulation, comprising at least the following steps:

[0007] S1: Winding structure data acquisition: By measuring and analyzing the actual structure of the transformer winding, the geometric parameters of each winding are determined. Combined with the actual winding form, a winding model construction plan is formed;

[0008] S2: Determine the conductor cross-section model, choose whether to simplify the conductor based on actual calculation requirements, and determine the simplification method;

[0009] S3: The winding path of the winding conductor is determined, and the winding direction and winding sequence are marked by numbering the two-dimensional cross-sectional view of the winding conductor;

[0010] S4: Winding 3D modeling: Use simplified parameters to build a 3D model of the winding to ensure that the model can accurately reflect the shape and size of the actual winding.

[0011] Furthermore, the geometric parameters in S1 include at least the length, diameter, number of layers, number of turns and thickness of the insulation material of the winding;

[0012] The actual winding forms in S1 include at least spiral, tangled and intertwined winding structures.

[0013] Furthermore, the step S3 at least includes the following steps:

[0014] In polar coordinates, combined with the conductor connection number cross-section diagram, based on the Archimedean equidistant spiral formula ρ(θ)=ρ0+bθ, the winding conductor segment is deconstructed, the winding conductor segment path is deconstructed, and the conductor winding path is drawn according to the actual winding situation of the winding conductor path;

[0015] By adjusting the polar angle θ and the polar diameter ρ0 in the Archimedean equidistant spiral formula, the starting point of each conductor path and the conductor transposition connection point can be determined;

[0016] Adjust the Archimedean spiral coefficient to control path-related parameters.

[0017] Furthermore, the three-dimensional model in S4 includes at least the specific shape and position of each layer and each turn of the winding and the arrangement of insulation materials and cooling channels between different layers;

[0018] It is used to arrange the conductor structure by determining the number and distribution of winding layers, as well as the specific shape and size of the cross-section of the conductor of each layer of winding, in conjunction with the winding path.

[0019] Furthermore, after establishing a three-dimensional model of the winding, the conductor and insulation layer parts in the winding model were meshed, and the finite element method was used to calculate the electric field distribution in the three-dimensional model. The electric field intensity distribution in the winding conductor cross-section, inter-turn and inter-layer oil channels was obtained respectively. Based on the analysis and calculation results, the influence of different insulation thicknesses and oil channel widths on the electric field distribution was evaluated.

[0020] Furthermore, the simplified method in S2 at least includes:

[0021] Merge the multi-conductor winding structure into a rectangular cross-section, retaining the key structure and reducing the complexity of the model;

[0022] While ensuring the accuracy of the calculation problem, multiple parallel conductors are simplified into one equivalent conductor, and the thickness of the thin layer of insulation material is simplified to reduce the number of grids and the calculation complexity;

[0023] According to the requirements of simulation accuracy in different areas, adaptive meshing technology can be used to mesh the three-dimensional model. Finer meshes can be used for key parts to improve simulation accuracy, and coarser meshes can be used for relatively less important areas to reduce the amount of calculation.

[0024] Furthermore, the three-dimensional model in S4 includes defining the physical properties of different materials;

[0025] The physical properties of the different materials are defined to include at least the electrical conductivity, density, specific heat capacity and mechanical performance parameters of the conductor material (such as copper or aluminum), and the electrical insulation performance, thermal conductivity and mechanical performance parameters of the insulating material.

[0026] Furthermore, the three-dimensional model in S4 needs to set simulation boundary conditions and excitation conditions according to the actual working environment and operating conditions of the target object;

[0027] The boundary conditions and excitation conditions of the simulation are set to include at least boundary conditions of electromagnetic field simulation, boundary conditions of thermal field simulation and boundary conditions of stress field simulation;

[0028] The boundary conditions of the electromagnetic field simulation include at least voltage, current and magnetic field distribution;

[0029] The boundary conditions of the thermal field simulation include at least the ambient temperature, the cooling medium temperature and the heat transfer coefficient;

[0030] The boundary conditions of the stress field simulation include at least the mechanical stress and displacement boundary conditions on the winding.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. Through innovative modeling technology and optimization algorithms, the present invention can improve modeling efficiency while ensuring model accuracy, construct a more accurate three-dimensional winding model, and provide a solid foundation for finite element simulation of transformer windings. By performing simulation analysis of the electromagnetic field, temperature field, and stress field on the model, detailed performance data of the winding under different working conditions can be obtained, thereby providing a theoretical basis and technical support for the design, optimization, and simulation of the winding.

[0033] 2. The method of the present invention is not only applicable to the research and development and design of new transformers, but can also effectively improve the accuracy and efficiency of transformer winding simulation. It is suitable for the research and development and design of new transformers as well as the performance evaluation and fault analysis of existing transformers, thereby improving the operational reliability and safety of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 This is a flow chart of simulation calculation of transformer winding model of the present invention;

[0036] Figure 2 The winding cross-section parameter determination and simplified schematic diagram of the present invention;

[0037] Figure 3 This is a schematic diagram of the winding connection sequence numbering of the present invention;

[0038] Figure 4 This is a schematic diagram of the winding path planning based on the deconstruction of the Archimedean spiral equation according to the present invention;

[0039] Figure 5 A schematic diagram of the overall winding model of the present invention;

[0040] Figure 6 Schematic diagram of the grid division of the winding conductor and insulation layer of the present invention;

[0041] Figure 7 This is a cross-sectional diagram of the electric field simulation calculation results of the winding of the present invention;

[0042] Figure 8 Schematic diagram of the distribution of the inter-turn insulation electric field of the winding along the winding path of the present invention;

[0043] Figure 9 This is a schematic diagram of the electric field distribution of the insulation between winding layers (oil channel) along the winding path of the present invention;

[0044] Figure 10 This is a screenshot of the temperature rise simulation of the winding model of the present invention. DETAILED DESCRIPTION

[0045] The technical solutions 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, rather than all the embodiments.

[0046] The present invention proposes a three-dimensional transformer winding structure modeling method suitable for finite element simulation. Through innovative modeling technology and optimization algorithm, it can improve modeling efficiency while ensuring model accuracy, providing reliable technical support for the design and simulation of transformer windings. This method is not only suitable for the research and development and design of new transformers, but can also be applied to the performance evaluation and fault analysis scenarios of existing transformers, thereby improving the operational reliability and safety of the power system.

[0047] The concept of the present invention is:

[0048] Based on the target transformer winding structure being modeled, the geometric parameters of each winding are determined, including the winding length, diameter, number of layers, number of turns, and thickness of the insulation material. The actual winding form is determined, including but not limited to spiral, tangled, or interlaced winding structures. The winding path is deconstructed using the Archimedean spiral equation, and the winding starting path and interturn spacing are modulated using the equation parameters. The conductor cross-section is determined and swept along the winding path to obtain the main structure of the winding conductor. Transposition wires are then placed at reserved transposition points to ultimately achieve interconnection of the conductor paths. After arranging the interturn and interlayer insulation, the structural model of the target winding is obtained, and the required simulation calculations are performed based on the resulting winding model.

[0049] Example 1:

[0050] This embodiment discloses a method for detecting and simplifying the dimensional parameters of actual transformer windings to establish a three-dimensional model and calculate the electric field distribution under AC withstand voltage conditions. The specific steps are as follows:

[0051] like Figure 1 As shown, the actual size parameters of the transformer winding are obtained, including the geometric dimensions of the conductor, insulation thickness and oil channel width.

[0052] The conductor is simplified and the thin insulation layer is merged into a rectangular cross-section to reduce the complexity of the model.

[0053] like Figure 2 As shown, the winding direction and winding sequence are marked by numbering the two-dimensional cross-sectional view of the winding conductor.

[0054] like Figure 3 As shown, combined with the conductor connection number cross-section diagram, the Archimedean spiral equation is used to deconstruct the winding conductor segment, deconstruct the winding conductor segment path, and leave the connection end. The current flow order is A→B→C→D→E→F→G→H.

[0055] like Figure 4 As shown, a three-dimensional model of the winding is established, including the spiral shape of the conductor and the transposed conductor part to form the overall structure of the winding.

[0056] like Figure 5 As shown in the figure, the conductor and insulation layer parts in the winding model are meshed.

[0057] like Figures 6 to 9 As shown in Figure 1, the finite element method (FEM) was used to calculate the electric field distribution in the three-dimensional model. The electric field intensity distribution in the winding conductor cross-section, between turns, and in the oil channels between layers was obtained. The calculation results were analyzed to evaluate the effects of different insulation thicknesses and oil channel widths on the electric field distribution.

[0058] Example 2

[0059] This embodiment further designs corresponding thermal field simulation calculations based on the method disclosed in the above embodiment 1;

[0060] In thermal field simulation calculations, the three-dimensional winding geometry modeling method can be used to analyze the temperature distribution of the transformer winding during operation, thereby evaluating its heat dissipation performance.

[0061] Using similar steps as in Example 1, a three-dimensional model of the winding is constructed, focusing on describing the specific structures of the conductor layer, insulation layer and cooling channel, and performing mesh generation, such as Figures 1 to 5 shown.

[0062] Material property definition: Set thermophysical parameters such as thermal conductivity, specific heat capacity, and density of conductor and insulation materials.

[0063] Boundary condition setting: Set the boundary conditions such as the power loss distribution of the winding and the ambient temperature and cooling medium temperature.

[0064] Simulation calculation: Use finite element analysis software to perform thermal field simulation calculation to obtain the temperature distribution of each part of the winding.

[0065] like Figure 10 As shown, result analysis: Based on the simulation results, the heat dissipation performance of the winding is analyzed, possible overheating areas are identified, and the winding structure and cooling design are optimized to reduce potential factors affecting winding overheating.

[0066] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A transformer three-dimensional winding structure modeling method suitable for finite element simulation, characterized by: At least the following steps are included: S1: Winding structure data acquisition: By measuring and analyzing the actual structure of the transformer winding, the geometric parameters of each winding are determined. Combined with the actual winding form, a winding model construction plan is formed; S2: Determine the conductor cross-section model, choose whether to simplify the conductor according to actual calculation requirements, and determine the simplification method; S3: The winding path of the winding conductor is determined, and the winding direction and winding sequence are marked by numbering the two-dimensional cross-sectional view of the winding conductor; S4: Winding 3D modeling: Use simplified parameters to build a 3D model of the winding to ensure that the model can accurately reflect the shape and size of the actual winding; The three-dimensional model in S4 includes at least the specific shape and position of each layer and each turn of the winding and the arrangement of insulation materials and cooling channels between different layers; It is used to arrange the conductor structure by determining the number and distribution of winding layers, as well as the specific shape and size of the cross-section of the conductor of each layer, in conjunction with the winding path; After establishing a three-dimensional model of the winding, the conductor and insulation layers in the winding model were meshed, and the finite element method was used to calculate the electric field distribution in the three-dimensional model. The electric field intensity distribution in the winding conductor cross-section, between turns, and in the oil channels between layers was obtained. Based on the analysis and calculation results, the effects of different insulation thicknesses and oil channel widths on the electric field distribution were evaluated. The three-dimensional model in S4 needs to set the simulation boundary conditions and excitation conditions according to the actual working environment and operating conditions of the target object; The boundary conditions and excitation conditions of the simulation are set to include at least boundary conditions of electromagnetic field simulation, boundary conditions of thermal field simulation and boundary conditions of stress field simulation; The boundary conditions of the electromagnetic field simulation include at least voltage, current and magnetic field distribution; The boundary conditions of the thermal field simulation include at least the ambient temperature, the cooling medium temperature and the heat transfer coefficient; The boundary conditions of the stress field simulation include at least the mechanical stress and displacement boundary conditions on the winding.

2. The transformer three-dimensional winding structure modeling method suitable for finite element simulation according to claim 1, characterized in that: The geometric parameters in S1 include at least the length, diameter, number of layers, number of turns and thickness of the insulation material of the winding; The actual winding forms in S1 include at least spiral, tangled and intertwined winding structures.

3. The transformer three-dimensional winding structure modeling method suitable for finite element simulation according to claim 1, characterized in that: The S3 at least includes the following steps: In polar coordinates, combined with the conductor connection number cross-section diagram, based on the Archimedean equidistant spiral formula, the winding conductor segments are deconstructed, the winding conductor segment paths are deconstructed, and the conductor winding paths are drawn according to the actual winding conditions of the winding conductor paths; By adjusting the polar angle and polar diameter in the Archimedean equidistant spiral formula, the starting point of each conductor path and the conductor transposition connection point can be determined; Adjust the Archimedean spiral coefficient to control path-related parameters.

4. The transformer three-dimensional winding structure modeling method suitable for finite element simulation according to claim 1, characterized in that: The simplified method in S2 at least includes: Merge the multi-conductor winding structure into a rectangular cross-section, retaining the key structure and reducing the complexity of the model; While ensuring the accuracy of the calculation problem, multiple parallel conductors are simplified into one equivalent conductor, and the thickness of the thin layer of insulation material is simplified to reduce the number of grids and the calculation complexity; According to the requirements of simulation accuracy in different areas, adaptive meshing technology can be used to mesh the three-dimensional model. Finer meshes can be used for key parts to improve simulation accuracy, and coarser meshes can be used for relatively less important areas to reduce the amount of calculation.

5. The transformer three-dimensional winding structure modeling method suitable for finite element simulation according to claim 1, characterized in that: The three-dimensional model in S4 includes the definition of physical properties of different materials; The physical properties of the different materials are defined to include at least the electrical conductivity, density, specific heat capacity and mechanical performance parameters of the conductor material, and the electrical insulation performance, thermal conductivity and mechanical performance parameters of the insulating material.

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