Power transformer multi-physical field coupling simulation analysis method and related device

Abstract

The invention discloses a power transformer multi-physics coupling simulation analysis method and a related device, and the method comprises the steps: constructing a corresponding geometric model and a multi-physics coupling model according to the obtained transformer data of a power transformer, and further determining a target simulation model; inputting a preset direct-current magnetic bias current into the target simulation model to simulate a direct-current magnetic bias state, and performing finite element analysis to obtain vibration displacement change distribution and sound pressure distribution; and according to the vibration displacement change distribution and the sound pressure distribution, determining the weak position of the power transformer influenced by the preset direct-current magnetic bias current. Therefore, accurate analysis and prediction of vibration and noise characteristics of the power transformer in the direct-current magnetic bias environment are realized by establishing a multi-physics field coupling model for analysis.

Description

Technical Field

[0001] This application relates to the field of power transformer analysis technology, and in particular to a multi-physics coupling simulation analysis method and related apparatus for power transformers. Background Technology

[0002] In high-voltage direct current (HVDC) transmission systems and AC power grids near grounding electrodes, the presence of DC bias magnetization often leads to abnormal vibrations and noise in power transformers. In severe cases, this phenomenon can cause aging of transformer insulation materials and a series of mechanical failures. Therefore, it is necessary to predict the vibration and noise of power transformers under DC bias magnetization conditions.

[0003] Current analysis and research on the vibration characteristics of power transformers have significant limitations, failing to fully reflect the complex coupling mechanisms between different physical fields under DC bias conditions. Therefore, a multi-physics coupling simulation analysis method for power transformers is urgently needed to improve the accuracy of predicting the vibration and noise characteristics of power transformers. Summary of the Invention

[0004] This application provides a multi-physics coupling simulation analysis method and related device for power transformers. By establishing a multi-physics coupling model for analysis, it achieves accurate analysis and prediction of the vibration and noise characteristics of power transformers under DC biased magnetic environment.

[0005] In a first aspect, embodiments of this application provide a multiphysics coupling simulation analysis method for power transformers, the method comprising: Obtain transformer data for power transformers; the transformer data includes: transformer structural parameters and material property parameters; Based on the transformer data, a geometric model corresponding to the power transformer is constructed, and a multiphysics coupling model is established; the geometric model and the multiphysics coupling model are fused to obtain the target simulation model; the multiphysics coupling model includes: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model; A preset DC bias current is input into the target simulation model, and finite element analysis is performed on the target simulation model to obtain the vibration displacement change distribution and sound pressure distribution; the DC bias current is a current with a preset amplitude and a preset direction; Based on the vibration displacement change distribution, the first weak location data of the power transformer affected by the preset DC bias current is determined, and the first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. The second weak location data of the power transformer affected by the preset DC bias current is determined based on the sound pressure distribution. The second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution.

[0006] Secondly, embodiments of this application provide a multiphysics coupling simulation analysis device for power transformers. The device includes: a data acquisition module, a multiphysics coupling model construction module, a simulation analysis module, a first weak point calculation module, and a second weak point calculation module. The data acquisition module is used to acquire transformer data of the power transformer; the transformer data includes: transformer structural parameters and material property parameters; The multiphysics coupling model construction module is used to construct the geometric model corresponding to the power transformer based on the transformer data, and establish a multiphysics coupling model; the geometric model and the multiphysics coupling model are fused to obtain the target simulation model; the multiphysics coupling model includes: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model; The simulation analysis module is used to input a preset DC bias current into the target simulation model, perform finite element analysis on the target simulation model, and obtain the vibration displacement distribution and sound pressure distribution; the DC bias current is a current with a preset amplitude and a preset direction; The first weak location calculation module is used to determine the first weak location data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution. The first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. The second weak location calculation module is used to determine the second weak location data of the power transformer affected by the preset DC bias current based on the sound pressure distribution. The second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution.

[0007] Thirdly, embodiments of this application provide an electronic device, including: a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, and the programs include instructions for performing the steps in the first aspect of embodiments of this application.

[0008] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program for electronic data interchange, wherein the computer program causes a computer to perform some or all of the steps described in the first aspect of embodiments of this application.

[0009] Fifthly, embodiments of this application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps described in the first aspect of embodiments of this application. The computer program product may be a software installation package.

[0010] It can be seen that the embodiments of this application have the following beneficial effects: By implementing the embodiments of this application, transformer data of a power transformer is obtained; a geometric model corresponding to the power transformer is constructed based on the transformer data, and a multiphysics coupling model is established; the geometric model and the multiphysics coupling model are fused to obtain a target simulation model; a preset DC bias current is input into the target simulation model, and finite element analysis is performed on the target simulation model to obtain the vibration displacement change distribution and sound pressure distribution; the first weak point data of the power transformer affected by the preset DC bias current is determined based on the vibration displacement change distribution; the second weak point data of the power transformer affected by the preset DC bias current is determined based on the sound pressure distribution. It can be seen that by establishing a multiphysics coupling model for analysis, accurate analysis and prediction of the vibration and noise characteristics of a power transformer under DC bias environment can be achieved. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or the background art, the accompanying drawings used in the embodiments of this application or the background art will be described below.

[0012] Figure 1 This is a flowchart illustrating a multiphysics coupling simulation analysis method for power transformers provided in an embodiment of this application. Figure 2 This is a schematic diagram of the structure of a geometric model of a power transformer provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of an external circuit model provided in an embodiment of this application; Figure 4 This is a simulation diagram of transformer tank vibration provided in an embodiment of this application; Figure 5 This is a transformer tank displacement variation curve provided in an embodiment of this application; Figure 6 This is a point selection diagram of a noise sound pressure transformer provided in an embodiment of this application; Figure 7 This is a transformer sound pressure distribution diagram provided in an embodiment of this application; Figure 8 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 0A; Figure 9 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 8.13A; Figure 10 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 14A; Figure 11 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 32.53A; Figure 12 This is a schematic diagram of the structure of a multiphysics coupling simulation analysis device for power transformers provided in an embodiment of this application; Figure 13 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0013] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0014] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0015] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0016] The following describes the relevant content, concepts, meanings, technical issues, technical solutions, and beneficial effects involved in the embodiments of this application.

[0017] Please see Figure 1 , Figure 1This is a flowchart illustrating a multiphysics coupling simulation analysis method for power transformers provided in an embodiment of this application. The method includes, but is not limited to, the following steps: S101. Obtain transformer data of the power transformer.

[0018] In this embodiment of the application, the power transformer can be a three-phase three-column power transformer, which includes three core columns.

[0019] In this embodiment of the application, the transformer data includes: transformer structural parameters and material property parameters.

[0020] Among them, transformer structural parameters refer to the set of parameters of geometric dimensional characteristics of various components of a power transformer, which may include the core column diameter, side column width, yoke height, total lamination height, inner diameter, outer diameter, axial height, and number of turns of the winding, as well as the length, width, and height of the tank and other dimensional parameters.

[0021] It should be noted that, in the embodiments of this application, the oil tank can be physically modeled and the geometric model of the power transformer can be placed in the oil tank model. The oil tank can withstand the structural vibrations caused by magnetostriction, electrodynamics, etc., and then transmit the vibrations to the surrounding medium (transformer oil or air) in the form of sound radiation. Therefore, by simulating and analyzing the vibration displacement and noise pressure of the oil tank wall, the influence of DC bias magnetism on the mechanical and acoustic performance of the power transformer can be determined.

[0022] Material property parameters refer to the set of parameters of the physical properties of the materials used in various components of a power transformer. These parameters may include the anisotropic permeability, BH curve (nonlinear magnetization characteristic curve), and iron loss curve (eddy current loss and hysteresis loss characteristic curve) of the core material, the resistivity and temperature correction coefficient of the winding material, and the dielectric constant and withstand voltage rating of the insulation material.

[0023] In a specific embodiment, transformer data of a power transformer can be obtained from the design drawings, technical specifications and measured data of the power transformer. For example, the cross-sectional dimensions such as the core column diameter, side column width and yoke height can be obtained from the design drawings, and the total height of the core laminations and the lamination coefficient (i.e. the ratio of the effective height of the silicon steel sheets after lamination to the theoretical height) can be determined by combining the actual measurements.

[0024] It is evident that by accurately obtaining the structural and material property parameters of the transformer, complete and accurate basic data can be provided for the subsequent construction of the geometric model of the power transformer and the establishment of a multiphysics coupling simulation model, effectively avoiding model distortion caused by missing or incorrect parameters.

[0025] S102. Construct a geometric model corresponding to the power transformer based on the transformer data, and establish a multiphysics coupling model; fuse the geometric model and the multiphysics coupling model to obtain the target simulation model.

[0026] In this embodiment of the application, the geometric model refers to a digital model constructed using three-dimensional modeling techniques based on the actual structural dimensions of the power transformer, which is an assembly of core components such as the power transformer core, windings, and tank.

[0027] In this embodiment, the multiphysics coupling model serves as the core model for simulating and analyzing the multiphysics characteristics of a transformer. It integrates mathematical models of physical fields such as electric field, magnetic field, sound field, temperature field, and structural force field. The multiphysics coupling model may include: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model.

[0028] In this embodiment of the application, the target simulation model refers to the complete simulation model formed by data association and functional fusion of the geometric model and the multiphysics coupling model. It can realize the collaborative calculation of geometric space and physical field characteristics and be directly used for the simulation analysis of transformer vibration and noise characteristics under DC bias conditions.

[0029] In a specific embodiment, a geometric model corresponding to the power transformer can be constructed based on the transformer data, and a multiphysics coupling model can be established.

[0030] It should be noted that the embodiments of this application can be simulated and analyzed in COMSOL Multiphysics finite element simulation software. This software covers fields such as electromagnetics, acoustics, heat conduction, and structural mechanics. Therefore, electric field models, magnetic field models, sound field models, temperature field models, and structural force field models can be obtained from this software to establish multiphysics coupling models.

[0031] Next, the geometric model and the multiphysics coupling model are fused to obtain the target simulation model.

[0032] Optionally, the transformer structural parameters include: core size data and winding size data; the above step: constructing the geometric model corresponding to the power transformer based on the transformer data specifically includes the following steps: A201. Construct a cylindrical core structure model and a rectangular yoke structure model based on the core size data; A202. Merge the cylindrical core structure model and the rectangular yoke structure model into a core foundation model by using Boolean union operation; A203. Based on the winding size data, establish winding models on the cylindrical core structure of the iron core base model respectively; the winding models include high-voltage winding models and low-voltage winding models; A204. Determine the material parameters used for the core foundation model and the winding model based on the material property parameters to obtain the geometric model corresponding to the power transformer.

[0033] In this embodiment, the cylindrical core column structure model is a cylindrical core load-bearing and magnetic conduction structure model constructed based on the core size data column diameter and the total height of the laminations, and is used for winding the coil.

[0034] The rectangular yoke structure model is a rectangular core connection structure model constructed based on the yoke height, width, and total lamination height parameters in the core size data. It is used to connect the cylindrical core columns to form a closed magnetic circuit.

[0035] In a specific embodiment, the core column diameter parameter is first extracted from the core size data. A circular cross-section matching the core column diameter is drawn in a two-dimensional plane (such as the xy plane). Then, the total lamination height and lamination coefficient parameters in the core size data are obtained. The equivalent lamination height of the core is calculated based on the lamination coefficient, which is the product of the total lamination height and the lamination coefficient. The circular cross-section is then three-dimensionally stretched along a direction perpendicular to the two-dimensional cross-section (such as the z-axis direction). The stretching height is set to the calculated equivalent lamination height, thereby forming a cylindrical core column structure model.

[0036] Then, the yoke height and width parameters are extracted from the core size data, and the corresponding rectangular cross-section is drawn in a two-dimensional plane. Similarly, the equivalent stacking height is calculated based on the total height of the laminations and the lamination coefficient. The rectangular cross-section is then three-dimensionally stretched along the z-axis, and the stretching height is consistent with the stretching height of the cylindrical core column structure model. In this way, the rectangular yoke structure model is constructed.

[0037] Next, the cylindrical core structure model and the rectangular yoke structure model are merged into a basic core model through Boolean union operation, which is an overall core model with a complete magnetic circuit.

[0038] After completing the core modeling, high-voltage and low-voltage winding models can be constructed on the outer layer of the cylindrical core structure model according to the three-phase distribution of A / B / C, based on parameters such as the inner diameter, outer diameter, axial height, and number of turns of the winding. The winding model adopts equivalent thickness simplification treatment, that is, it is converted into a uniform cylindrical layer without subdivision insulation according to the proportion of the total cross-sectional area of ​​the metal conductor, so as to make the metal volume of the winding before and after the equivalent thickness is consistent.

[0039] Finally, the material parameters used for the core foundation model and winding model can be determined based on the material property parameters to obtain the geometric model of the power transformer.

[0040] Furthermore, by combining the overall width, length, and height parameters of the power transformer, geometric modeling of structures such as the oil tank can be added to form a complete geometric model of the power transformer.

[0041] Please see Figure 2 , Figure 2 This is a schematic diagram of the geometric model of a power transformer provided in an embodiment of this application. Figure 2 As shown, the transparent outer cube in the figure is the transformer's oil tank, which is filled with transformer oil. The transformer oil serves as an insulating medium to prevent faults such as discharge from occurring inside the tank. At the same time, the transformer oil also serves as a cooling medium to transfer the heat generated during transformer operation to the tank wall and can be used for subsequent temperature field analysis.

[0042] The oil tank contains a combination of components such as an iron core and windings. The three cylindrical structures labeled A, B, and C represent the A-phase winding, B-phase winding, and C-phase winding of the three-phase winding, respectively. These three-phase windings are fitted onto the iron core and are used to transmit and convert electrical energy under the influence of physical fields such as electric and magnetic fields. Based on a geometric model, and combined with multi-physics coupled models including electric field, magnetic field, sound field, temperature field, and structural force field models, finite element simulation analysis can be performed under DC biased magnetization conditions to predict weak points in the vibration and noise characteristics of power transformers.

[0043] It is evident that constructing a geometric model of a power transformer using transformer data, ensuring that its structural form closely matches that of an actual transformer and its material properties closely resemble the physical properties of the actual components, can provide an accurate geometric model for subsequent simulation analysis.

[0044] Optionally, the above steps, including establishing a multiphysics coupling model, specifically include the following steps: B201. The electric field model, the magnetic field model, the sound field model, the temperature field model, and the structural force field model are coupled according to the preset multiphysics coupling relationship to obtain the multiphysics coupling model; The multiphysics coupling relationships include: magnetic-structure coupling, thermal-structure coupling, structure-acoustic field coupling, and electric-magnetic coupling. The magnetic-structure coupling relationship is used to couple the magnetic field model and the structural force field model; the thermal-structure coupling relationship is used to couple the temperature field model and the structural force field model; the structure-acoustic field coupling relationship is used to couple the structural force field model and the acoustic field model; and the electric-magnetic coupling relationship is used to couple the electric field model and the magnetic field model.

[0045] In this embodiment, the preset multi-physics coupling relationship refers to the data transmission rules and interaction logic predefined for associating electric field model, magnetic field model, sound field model, temperature field model and structural force field model based on the actual interaction mechanism between various physical fields during the operation of the power transformer.

[0046] Among them, the magnetic-structural coupling relationship characterizes the correlation rules of the interaction between the magnetic field model and the structural force field model. It mainly transfers the magnetostrictive force and winding electrodynamic force calculated by the magnetic field model to the structural force field model as the load input for structural vibration and deformation analysis.

[0047] The thermal-structural coupling relationship is a correlation rule that characterizes the interaction between the temperature field model and the structural force field model. It mainly transfers the temperature distribution of each component output by the temperature field model to the structural force field model, and combines the thermal expansion characteristics of the material to transform it into thermal stress and thermal deformation load in the structural force field.

[0048] The coupling relationship between structure and sound field is a correlation rule that characterizes the energy transfer between the structural force field model and the sound field model. It mainly uses the vibration displacement and vibration velocity of structural components such as oil tanks calculated by the structural force field model as the boundary excitation of the sound field model, driving the sound field model to analyze the generation and propagation process of noise.

[0049] The electric-magnetic coupling relationship is a correlation rule characterizing the electromagnetic induction and energy conversion between the electric field model and the magnetic field model. By simultaneously solving Maxwell's equations, the winding voltage and capacitance distribution in the electric field model and the winding current and magnetic flux density in the magnetic field model can be solved in a coordinated manner, reflecting the intrinsic mechanism of the electromagnetic field.

[0050] In a specific embodiment, the electric field model, magnetic field model, acoustic field model, temperature field model, and structural force field model can be coupled according to preset multiphysics coupling relationships to obtain a multiphysics coupling model. Specifically, the specific implementation logic and data transmission path of each coupling relationship can be determined, and the association and integration of each physical field model can be completed in stages based on the coupling interface function of the finite element simulation software.

[0051] To realize the coupling relationship between magnetism and structure, a coupling interface between magnetic field and solid mechanics can be called in the simulation software. This interface predefines the force transmission logic between the magnetic field and the structural field. Specifically, the magnetic field model can be solved first. The magnetostrictive force in the core region and the electrodynamic force in the winding region can be calculated using the governing equations of the magnetic field model (Ampere's circuital law, magnetic flux continuity equation, etc.). Then, the calculated magnetostrictive force and electrodynamic force are automatically mapped to the corresponding core and winding spatial regions of the structural force field model through the coupling interface, serving as volume forces or surface forces loads for the structural force field model. This allows the structural force field model to analyze the vibration displacement and deformation of the core and winding based on these loads, thus completing the coupling between the magnetic field model and the structural force field model. For example, the magnetic field calculation yields a magnetostrictive force amplitude of 200 N / m in the core. 2 (Radial along the core column) Winding electrodynamic force 150 N / m 2(Along the winding axis), these two forces are applied to the core / winding region of the structural model, and the maximum radial deformation of the core is 0.08 mm and the axial displacement of the winding is 0.1 mm, simulating the structural deformation caused by electromagnetic force.

[0052] To realize the coupling relationship between heat and structure, a coupling interface for heat and solid mechanics can be called in the simulation software. This interface predefines the heat load transfer logic between the temperature field and the structural field. Specifically, the temperature field model can be run first to calculate the temperature distribution of various components such as the core, winding, and oil tank (including the hot spot temperature of the winding and the average temperature of the core) according to the heat conduction equation. The coupling interface will then convert the temperature distribution output by the temperature field model into thermal stress and thermal deformation driving loads in the structural force field model according to the predefined thermal expansion coefficient association rules and the thermal expansion coefficients of each component in the material property parameters. Subsequently, these thermal loads are applied to the corresponding component regions of the structural force field model, so that the structural force field model can simultaneously consider the influence of thermal effects when analyzing vibration and deformation, thus realizing the coupling between the temperature field model and the structural force field model. For example, if the temperature field calculates a winding hot spot temperature of 105℃, an average core temperature of 80℃, and an oil tank temperature of 55℃, this temperature distribution can be imported into the structural field and substituted with copper (with a thermal expansion coefficient of 16.5 × 10⁻⁶). -6 / ℃), silicon steel sheets (thermal expansion coefficient is 11×10⁻⁶). -6 The thermal expansion parameters ( / ℃) were used to solve for the radial thermal stress of 50MPa and the thermal deformation at the core joint of the winding due to thermal expansion.

[0053] To realize the coupling relationship between structure and sound field, a coupling interface for the interaction between sound and structure can be called in the simulation software. This interface predefines the energy transfer logic between structural vibration and sound field radiation. Specifically, the structural force field model can be solved first to calculate the vibration displacement and vibration velocity of key structural components such as the outer wall of the oil tank. The coupling interface will use the vibration displacement and vibration velocity output by the structural force field model as boundary conditions for the sound field model, and apply them to the solid-fluid (transformer oil, air) contact surface in the sound field model. The sound field model is based on the fluid sound wave equation. Using this boundary excitation as input, it calculates the sound pressure distribution, noise propagation path, and other characteristics in the transformer oil domain and the surrounding air domain, thereby completing the coupling between the structural force field model and the sound field model. For example, the structural field calculations yielded a vibration displacement amplitude of 0.1 mm and a vibration velocity of 0.05 m / s for the sidewall of the oil tank. These vibration parameters were set as the "solid-fluid boundary excitation" of the acoustic field model and solved in the domains of transformer oil (sound velocity 1400 m / s) and surrounding air (sound velocity 340 m / s). The results showed a sound pressure of 80 dB on the surface of the oil tank and a sound pressure of 65 dB in the air at a distance of 1 m, simulating transformer noise radiation.

[0054] To realize the coupling relationship between electricity and magnetism, based on the inherent correlation of Maxwell's equations, a collaborative solution can be achieved by calling the coupling interface between the electric and magnetic fields in the simulation software. Specifically, in the electric field model, based on parameters such as the rated voltage of the winding and the dielectric constant of the insulating material, the capacitance distribution and electric field intensity distribution between the windings can be obtained. Then, through the coupling interface, the capacitance parameters calculated by the electric field model and the winding resistance parameters (calculated by combining the resistivity after correction with the temperature field model) are substituted into the circuit equations to obtain the rated operating current of the winding. Subsequently, this current is used as the current load of the magnetic field model and input to the winding region of the magnetic field model. Based on the governing equations such as Ampere's circuital law, the magnetic field model, combined with the current load and the magnetic property parameters of the core material, obtains the magnetic flux density distribution, leakage flux distribution, and other magnetic field characteristics. At the same time, the magnetic flux change calculated by the magnetic field model will have a reaction effect on the electric field model, affecting the calculation of the induced electromotive force in the electric field model. Through this bidirectional data transfer, a deep coupling between the electric field model and the magnetic field model is achieved. For example, by applying a rated line voltage of 110kV to the high-voltage winding of the electric field model, the inter-winding capacitance is calculated to be 0.02μF. Substituting this capacitance and the winding resistance (0.5Ω after temperature correction) into the circuit equation, the rated winding current of 100A is obtained. Then, the current is used as the current load of the magnetic field model, and the core magnetic flux density of 1.7T and the winding leakage magnetic flux density of 0.3T are solved simultaneously to simulate the real distribution under the interaction of electromagnetic fields.

[0055] It is evident that by pre-setting multi-physics coupling relationships and achieving coupling of multiple physics models by type, the actual interaction mechanism between electric field, magnetic field, sound field, temperature field and structural force field during the operation of power transformer can be accurately reproduced. This avoids simulation deviations caused by neglecting the mutual influence between fields in a single physics model, and provides a reliable model foundation for the construction of subsequent target simulation models and the accurate analysis of vibration and noise characteristics under DC bias conditions.

[0056] Optionally, the above step of fusing the geometric model with the multiphysics coupling model to obtain the target simulation model specifically includes the following steps: C201. The geometric model is meshed to obtain a meshed geometric model; the mesh shape includes at least one of the following: triangular, quadrilateral, and hexagonal; C202. Import the meshed geometric model into a preset finite element simulation environment, and associate the meshed geometric model with the coupling equations corresponding to each physical model in the multiphysics coupling model to obtain the target simulation model; the preset finite element simulation environment is used to perform finite element analysis on the target simulation model.

[0057] In this embodiment of the application, the preset finite element simulation environment refers to finite element simulation software (such as COMSOL Multiphysics) that has been pre-configured with solvers, physics calculation modules, and data interaction interfaces. This environment can support the fusion of multiphysics coupling models and geometric models, and realize finite element numerical calculation and result output.

[0058] In a specific embodiment, the geometric model is divided into meshes to obtain a meshed geometric model, wherein the mesh shape includes at least one of the following: triangular, quadrilateral, and hexagonal.

[0059] When importing a meshed geometric model into a preset finite element simulation environment and associating it with the coupling equations of a multiphysics coupling model to obtain the target simulation model, the process is as follows: First, the preset finite element simulation environment is started. The meshed geometric model is then completely imported through the environment's geometric model import interface, ensuring that the model's spatial coordinates and component relationships are accurate during the import process. Subsequently, based on the structure of the multiphysics coupling model, the association between the meshed geometric model and the coupling equations of each physics field is established one by one to obtain the target simulation model.

[0060] It is evident that by selectively meshing the geometric model, we can ensure that the meshed geometric model has sufficient discretization accuracy in the key regions of each physics calculation, enabling the multiphysics coupling equations to be solved accurately.

[0061] S103. Input a preset DC bias current into the target simulation model, perform finite element analysis on the target simulation model, and obtain the vibration displacement change distribution and sound pressure distribution.

[0062] In this embodiment, the DC bias current is a current with a preset amplitude and a preset direction. Its parameters need to fit the typical interference range of DC bias in engineering, and are used to simulate the DC bias state when the transformer is running.

[0063] In this embodiment of the application, the vibration displacement change distribution refers to the distribution data formed by arranging the vibration displacement values ​​of each component (such as the tank wall, iron core, and winding) in the target simulation model at different times according to their spatial positions, obtained through finite element analysis. This data can intuitively reflect the intensity and trend of vibration in each region.

[0064] Sound pressure distribution refers to the sound pressure distribution data at different spatial locations in the fluid domain (transformer oil, air) surrounding the target simulation model, obtained through finite element analysis. It is used to characterize the radiation intensity and propagation range of transformer noise.

[0065] In a specific embodiment, a preset DC bias current is input into the target simulation model, and finite element analysis is performed on the target simulation model to obtain the vibration displacement change distribution and sound pressure distribution.

[0066] It is evident that by inputting a preset DC bias current into the target simulation model and conducting finite element analysis, the actual operating state of the transformer under DC bias conditions can be accurately simulated. The obtained vibration displacement change distribution and sound pressure distribution can intuitively reflect the influence of DC bias on transformer vibration and noise.

[0067] Optionally, the above steps, including inputting a preset DC bias current into the target simulation model and performing finite element analysis on the target simulation model to obtain the vibration displacement distribution and sound pressure distribution, specifically include the following steps: A301. Construct an external circuit model; the external circuit model includes a left high-voltage circuit and a right low-voltage circuit; the left high-voltage circuit is used to provide the rated voltage; the right low-voltage circuit is used to maintain an open circuit; the external circuit model is used to simulate a DC bias state; A302. The external circuit model is coupled to the target simulation model by means of field circuit coupling method, and the preset DC bias current is input to the target simulation model; A303. Perform finite element calculations on the coupling equations of each physical field in the target simulation model to obtain the vibration displacement distribution and the sound pressure distribution.

[0068] In this embodiment of the application, the external circuit model refers to a circuit model constructed based on the actual circuit topology of the power transformer, used to simulate the external electrical connection state of the transformer. Its main function is to provide rated voltage excitation and DC bias current for the target simulation model, and to restore the electrical environment under DC bias conditions.

[0069] The field-circuit coupling method is a technical method for establishing data interaction and electrical connection between a finite element physical field model (target simulation model) and an external circuit model. By defining interface parameters, it realizes the accurate transmission of voltage and current excitation from the circuit model to the physical field model, as well as the feedback of electrical characteristic parameters of the physical field model to the circuit model.

[0070] Please see Figure 3 , Figure 3 This is a schematic diagram of an external circuit model provided in an embodiment of this application. For example... Figure 3 As shown, the external circuit model includes a high-voltage loop on the left and a low-voltage loop on the right. This external circuit model is used to simulate DC bias.

[0071] The left-hand high-voltage circuit provides the rated voltage. It connects each of the three high-voltage coils in series with an AC voltage source, then connects them in parallel to a DC current source. The DC current source provides a DC bias current, simulating a DC bias state for the power transformer. The AC voltage source provides the rated AC voltage to the transformer windings, simulating the AC power supply during normal operation, generating a rated AC current in the windings. This current, combined with the DC bias current, achieves the actual operating conditions. The left-hand high-voltage circuit contains high-voltage windings, specifically the coil section with resistors on the left side of the diagram.

[0072] The low-voltage circuit on the right is used to maintain an open circuit. This low-voltage circuit contains a low-voltage winding, which is the coil section with a resistor on the right side of the diagram.

[0073] The external circuit model is used to introduce the DC bias current and AC voltage of the external circuit into the transformer simulation model through the field-circuit coupling method, so as to change the magnetic field model in the simulation model, and then affect other physical fields such as structural force field and temperature field, thereby simulating the vibration and noise characteristics of power transformer under DC bias.

[0074] In a specific embodiment, an external circuit model is first constructed, which includes a left high-voltage loop and a right low-voltage loop. The left high-voltage loop is used to provide the rated voltage, and the right low-voltage loop is used to maintain an open circuit. The external circuit model is used to simulate a DC bias state.

[0075] For the left high-voltage circuit, following the three-phase circuit design principle, three independent AC voltage sources are configured. The voltage amplitude and frequency of each AC voltage source are consistent with the rated voltage parameters of the transformer's high-voltage side (e.g., when the rated line voltage on the high-voltage side is 10kV, the AC voltage source is set to the corresponding line voltage level). The three AC voltage sources are connected to the starting ends of the A, B, and C phase high-voltage windings in the target simulation model, respectively. Then, the ending ends of the three-phase high-voltage windings are connected in parallel to a DC current source. The current amplitude and direction of this DC current source are set according to preset DC bias current parameters (e.g., amplitude 5A, direction in the same direction as the rated current of phase A), thereby achieving the superposition of the DC bias current onto the high-voltage windings.

[0076] For the right low-voltage circuit, it is also designed as a three-phase circuit. The beginning and end of the three low-voltage windings are led out respectively, but no load components or power supply components are connected to keep the circuit open and ensure that no current flows on the low-voltage side. This simulates the no-load operation of the transformer. Finally, the external circuit model is built through circuit simulation software to ensure that the connection relationship between the left high-voltage circuit and the right low-voltage circuit is completely matched with the actual electrical interface of the transformer.

[0077] Next, the external circuit model is coupled to the target simulation model using the field-circuit coupling method, and a preset DC bias current is input to the target simulation model. Specifically, electrical interface terminals are set at the beginning and end of the high-voltage winding and the low-voltage winding of the target simulation model, with each interface terminal corresponding to the connection endpoint of the corresponding winding in the external circuit model. Then, the field-circuit coupling function is activated, binding the output terminal of the AC voltage source of the left high-voltage circuit in the external circuit model to the interface terminal at the beginning of the high-voltage winding of the target simulation model, and binding the output terminal of the DC current source to the common parallel node at the end of the high-voltage winding. The open-circuit endpoint of the right low-voltage circuit is bound to the interface terminals at the beginning and end of the low-voltage winding of the target simulation model, completing the establishment of the electrical connection relationship.

[0078] The high-voltage loop on the left side of the external circuit model first inputs the rated AC voltage to the high-voltage winding of the target simulation model. After the voltage stabilizes, the DC current source outputs the DC bias current according to the preset parameters. This current is superimposed on the current loop of the three-phase high-voltage winding through the parallel node, so as to accurately input the preset DC bias current to the target simulation model.

[0079] Finite element method (FEM) calculations are performed on the coupling equations of various physics fields in the target simulation model to obtain the vibration displacement distribution and sound pressure distribution. Specifically, a multiphysics solver is invoked in the preset FEM simulation environment. The solver first solves the coupling equations of the electric field model and the magnetic field model based on the voltage and current excitations transmitted by the field-circuit coupling. The force load calculated by the magnetic field is substituted into the coupling equations of the structural force field model. At the same time, the component temperature distribution calculated by the temperature field model is combined to solve the structural force field equations, obtaining the vibration displacement data of components such as the tank wall, core, and windings at different time steps. Finally, based on the coupling relationship between the structure and the sound field, the vibration displacement and velocity of the tank outer wall calculated by the structural force field are used as the boundary excitation of the sound field model to solve the sound field wave equation, obtaining the sound pressure values ​​of each spatial point in the transformer oil domain (sound speed approximately 1400 m / s) and the surrounding air domain (sound speed approximately 340 m / s). The sound pressure distribution is then formed by organizing the spatial coordinates and time steps.

[0080] It is evident that finite element calculations based on multi-physics coupling equations can obtain the distribution of vibration displacement and sound pressure, fully reflecting the influence of DC bias on the vibration and noise characteristics of transformers.

[0081] S104. Determine the first weak point data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution.

[0082] In this embodiment of the application, the first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. Based on the vibration displacement change distribution, it can filter out the location information corresponding to the area of ​​abnormal vibration displacement value in the power transformer. It can include the spatial coordinates of the area, the component affiliation (such as the tank wall, near the core column), and other data, which are used to determine the parts of the transformer with high vibration risk under DC bias magnetization conditions.

[0083] In a specific embodiment, a vibration displacement safety judgment standard can be determined first, that is, a preset vibration displacement safety threshold can be retrieved. This threshold needs to refer to the transformer structural strength design parameters, the vibration fatigue performance index of the insulation material, and the transformer vibration control standards in the industry to ensure the rationality and safety of the threshold setting. If the vibration displacement exceeds the threshold, it is judged as abnormal.

[0084] By filtering the first weak point data based on the vibration displacement change distribution and preset safety threshold, the area of ​​transformer vibration risk under DC bias can be accurately located.

[0085] Optionally, the above step of determining the first weak point data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution specifically includes the following steps: A401. Based on the vibration displacement change distribution, determine the vibration displacement value of each of the multiple first position points to obtain multiple vibration displacement values; the first position point is a pre-set monitoring point for monitoring the vibration effect; A402. Compare the plurality of vibration displacement values ​​with a preset vibration displacement threshold, and select a first position point whose vibration displacement value is greater than the preset vibration displacement threshold to obtain at least one first position point. A403. Determine the vibration displacement value corresponding to the at least one first position point to obtain at least one vibration displacement value; A404. Determine the first weak position data based on the at least one first position point and the at least one vibration displacement value.

[0086] In this embodiment of the application, the first location point refers to a monitoring point pre-set according to the vibration-prone areas and key structural parts of the power transformer, and its spatial distribution needs to cover vibration-sensitive areas such as the core column, winding ends, and tank wall.

[0087] The preset vibration displacement threshold is the maximum allowable value of vibration displacement set with reference to the design specifications of power transformers, structural strength requirements and industry vibration control standards. This threshold serves as the criterion for determining whether the first location point belongs to a vibration weak point.

[0088] Please see Figure 4 , Figure 4This is a simulation diagram of transformer tank vibration provided in an embodiment of this application. Figure 4 The study demonstrates the magnitude and distribution of vibration displacement in various parts of a power transformer under the influence of DC bias current.

[0089] The colors, from blue to red, represent changes in vibration displacement from small to large, with the unit of displacement being μm (micrometers). The color distribution allows for a direct visual representation of the differences in vibration intensity across different regions.

[0090] The red and orange areas in the diagram, which are the darker colored parts, show greater vibration displacement. This indicates that the vibration of the power transformer tank mainly originates from the vibration inside the iron core.

[0091] Please see Figure 5 , Figure 5 This is a transformer tank displacement variation curve provided in an embodiment of this application. Figure 5 As shown in the figure, this figure displays the curves of transformer tank displacement versus time under different DC bias currents.

[0092] The graph shows time on the horizontal axis (seconds) and displacement on the vertical axis (μm). Four curves correspond to different DC bias current conditions. The black curve represents the displacement when the DC bias current is 0A, which is the baseline condition (no DC bias). The red curve represents the displacement when the DC bias current is 8.13A. The blue curve represents the displacement when the DC bias current is 14A. The green curve represents the displacement when the DC bias current is 32.53A.

[0093] It should be noted that the reference transformer is a standard transformer used as a reference in the embodiments of this application, and its limit standard for the vibration displacement of the tank wall under the influence of DC bias is 100μm.

[0094] Therefore, as shown in the figure, when the DC current reaches 14A, the displacement of the transformer tank wall reaches the standard upper limit. Therefore, in the embodiment of this application, the preset DC bias current of the external circuit model entering the simulation model can be set to 14A, and the preset vibration displacement threshold can be set to 100μm.

[0095] In a specific embodiment, the vibration displacement value of each of the multiple first position points is determined based on the vibration displacement change distribution, resulting in multiple vibration displacement values. These multiple vibration displacement values ​​are compared with a preset vibration displacement threshold, and first position points with vibration displacement values ​​greater than the preset threshold are selected, resulting in at least one first position point. The vibration displacement value corresponding to the at least one first position point is determined, resulting in at least one vibration displacement value. Based on the at least one first position point and the at least one vibration displacement value, the first weak position data can be determined.

[0096] It can be seen that by extracting vibration displacement, comparing thresholds, and performing spatial analysis on the preset first position point, the location of transformer vibration exceeding the standard under DC bias can be accurately located.

[0097] S105. Determine the second weak point data of the power transformer affected by the preset DC bias current based on the sound pressure distribution.

[0098] In this embodiment, the second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution. Based on the sound pressure distribution, it is the location information corresponding to the area of ​​abnormal sound pressure level value of the power transformer under the influence of a preset DC bias current. It can include the spatial coordinates of the area, the component to which it belongs (such as the tank wall, near the core column), and sound pressure level characteristic parameters (such as the maximum sound pressure level and the average sound pressure level), which is used to identify the part of the transformer noise radiation that exceeds the standard under DC bias conditions.

[0099] The preset sound pressure level threshold is the maximum allowable sound pressure level set in advance according to the power transformer noise control standards, environmental noise requirements and equipment operation reliability indicators. When the sound pressure level exceeds this threshold, it indicates that the noise radiation in the corresponding area exceeds the standard, and it is determined to be a noise weak point.

[0100] In a specific embodiment, a noise safety judgment benchmark can be determined first, that is, a preset sound pressure level threshold can be retrieved. The setting of this threshold needs to refer to the noise limit corresponding to the rated capacity of the transformer, the noise emission standards of the installation environment, and the noise radiation characteristics of the equipment's own structure, to ensure that the threshold can meet the requirements for safe operation and fit the actual application scenario of the project. If the sound pressure level exceeds the threshold, it is judged as abnormal.

[0101] By filtering the second weak point data based on the sound pressure distribution and the preset sound pressure level threshold, the area where transformer noise radiation exceeds the standard under DC bias magnetic conditions can be accurately located.

[0102] Optionally, the above step of determining the second weak point data of the power transformer affected by the preset DC bias current based on the sound pressure distribution specifically includes the following steps: A501. Based on the sound pressure distribution, determine the sound pressure level data of each of the multiple second location points to obtain multiple sound pressure level data; the second location point is a pre-set monitoring point for monitoring the impact of noise; A502. Compare the multiple sound pressure level data with a preset sound pressure level threshold, and filter out the second position points where the sound pressure level data is greater than the sound pressure level threshold to obtain at least one second position point; A503. Determine the sound pressure level data corresponding to the at least one second location point to obtain at least one sound pressure level data; A504. Determine the second weak location data based on the at least one second location point and the at least one sound pressure level data.

[0103] In this embodiment, the second location point is a noise monitoring point pre-set according to the noise radiation characteristics and key structural areas of the power transformer. It can be a noise-sensitive area such as the tank wall, near the core column, the winding surface, and the air area around the transformer.

[0104] Please see Figure 6 , Figure 6 This is a point selection diagram for a noise sound pressure transformer provided in an embodiment of this application. For example... Figure 6 As shown, key locations such as the tank wall, near the core column, and on the winding surface of the power transformer can be selected to observe the transformer's noise level.

[0105] The preset sound pressure level threshold is the maximum allowable sound pressure level set with reference to relevant standards for power transformer noise control (and the noise allowable range of the equipment operating environment). This threshold is the criterion for determining whether the second location point belongs to a noise-weak location.

[0106] Please see Figure 7 , Figure 7 This is a transformer sound pressure distribution diagram provided in an embodiment of this application. Figure 7 The study demonstrates the magnitude and distribution of sound pressure at various points on a power transformer under the influence of a DC bias current.

[0107] The colors, from blue to red, represent changes in sound pressure from low to high. The unit of sound pressure is dB (decibels). The color distribution allows for a visual representation of the differences in noise intensity in different areas.

[0108] The red and orange areas in the diagram, which are darker in color, have higher sound pressure levels. This shows that the noise in the power transformer tank mainly originates from inside the iron core.

[0109] In a specific embodiment, sound pressure level data for each of a plurality of second location points is determined based on the sound pressure distribution, resulting in a plurality of sound pressure level data. The second location points are pre-defined monitoring points used to monitor the impact of noise. The plurality of sound pressure level data are compared with a preset sound pressure level threshold, and second location points with sound pressure level data greater than the threshold are selected, resulting in at least one second location point. The sound pressure level data corresponding to at least one second location point is determined, resulting in at least one sound pressure level data. Second weak point data is determined based on at least one second location point and at least one sound pressure level data.

[0110] Combination Figure 6 and Figure 7Analysis was conducted at any key location (such as the winding surface) of the power transformer. Four different DC bias currents of 0A, 8.13A, 14A, and 32.53A were set to observe the change in sound pressure at the selected point from 0 to 0.05s.

[0111] Please see Figure 8 , Figure 8 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 0A. For example... Figure 8 As shown, when the DC bias current is 0A, that is, the power transformer is in normal operation without DC bias, the transformer vibrates due to factors such as the magnetostriction of the core and the electromagnetic force of the windings during normal operation, which in turn radiates noise to the surroundings, resulting in certain fluctuations in sound pressure.

[0112] This curve serves as the sound pressure data under the baseline operating conditions and can be compared with the sound pressure curve when DC bias is present, thereby providing a clearer analysis of the impact of DC bias on the transformer's noise characteristics.

[0113] Please see Figure 9 , Figure 9 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 8.13A. Figure 9 As shown, when an 8.13A DC bias current is applied to the simulation model, the magnetic flux characteristics of the transformer core are altered, exacerbating the magnetostrictive effect. Simultaneously, the leakage flux and electrodynamic forces of the windings also change. These changes cause more severe vibrations in the transformer structure, which in turn radiate noise into the surrounding medium.

[0114] Compare the sound pressure curves when the DC bias current is 0A ( Figure 8 It can be observed that the fluctuation amplitude of the sound pressure increases significantly and the peak value also rises significantly, indicating that the presence of DC bias current will exacerbate the noise radiation of the transformer.

[0115] Please see Figure 10 , Figure 10 This is a sound pressure change curve provided in an embodiment of this application when the DC bias current is 14A. Figure 10 As shown, a DC bias current of 14A was connected to the simulation model, compared with a DC bias current of 0A ( Figure 8 ) and 8.13A ( Figure 9 The sound pressure curve at this time clearly shows that the fluctuation amplitude and peak value of the sound pressure further increase, which fully demonstrates that as the DC bias current increases, the noise radiation of the transformer becomes more and more serious.

[0116] Please see Figure 11 , Figure 11 This is a sound pressure variation curve provided in an embodiment of this application when the DC bias current is 32.53A. Figure 11 As shown, a DC bias current of 32.53A was connected to the simulation model, compared with a DC bias current of 0A ( Figure 8 ), 8.13A ( Figure 9 ) and 14A ( Figure 10 The sound pressure curve at this time clearly shows that the fluctuation amplitude and peak value of the sound pressure have increased significantly, which fully demonstrates that the noise radiation problem of the transformer is becoming more and more serious as the DC bias current continues to increase.

[0117] It can be seen that by extracting sound pressure level data, comparing thresholds, and performing spatial analysis on the preset second location point, the location where transformer noise radiation exceeds the standard under DC bias magnetic conditions can be accurately located.

[0118] In summary, by implementing the embodiments of this application, transformer data of a power transformer is obtained; a geometric model corresponding to the power transformer is constructed based on the transformer data, and a multiphysics coupling model is established; the geometric model and the multiphysics coupling model are fused to obtain a target simulation model; a preset DC bias current is input into the target simulation model, and finite element analysis is performed on the target simulation model to obtain the vibration displacement change distribution and sound pressure distribution; the first weak point data of the power transformer affected by the preset DC bias current is determined based on the vibration displacement change distribution; and the second weak point data of the power transformer affected by the preset DC bias current is determined based on the sound pressure distribution. It is evident that by establishing a multiphysics coupling model for analysis, accurate analysis and prediction of the vibration and noise characteristics of a power transformer under DC bias environment can be achieved.

[0119] Please see Figure 12 , Figure 12 This is a schematic diagram of the structure of a multiphysics coupling simulation analysis device for power transformers provided in an embodiment of this application. The multiphysics coupling simulation analysis device 700 for power transformers includes: a data acquisition module 701, a multiphysics coupling model construction module 702, a simulation analysis module 703, a first weak point calculation module 704, and a second weak point calculation module 705, wherein... The data acquisition module 701 is used to acquire transformer data of the power transformer; the transformer data includes: transformer structural parameters and material property parameters; The multiphysics coupling model construction module 702 is used to construct the geometric model corresponding to the power transformer based on the transformer data, and establish a multiphysics coupling model; the geometric model and the multiphysics coupling model are fused to obtain the target simulation model; the multiphysics coupling model includes: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model; The simulation analysis module 703 is used to input a preset DC bias current into the target simulation model, perform finite element analysis on the target simulation model, and obtain the vibration displacement distribution and sound pressure distribution; the DC bias current is a current with a preset amplitude and a preset direction; The first weak location calculation module 704 is used to determine the first weak location data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution. The first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. The second weak location calculation module 705 is used to determine the second weak location data of the power transformer affected by the preset DC bias current based on the sound pressure distribution. The second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution.

[0120] Optionally, the transformer structural parameters include: core size data and winding size data; in constructing the geometric model corresponding to the power transformer based on the transformer data, the multiphysics coupling model construction module 702 is further specifically used for: Based on the core size data, construct a cylindrical core structure model and a rectangular yoke structure model; The cylindrical core structure model and the rectangular yoke structure model are merged into a core foundation model by Boolean union operation. Based on the winding size data, winding models are established on the cylindrical core structure of the iron core base model; the winding models include high-voltage winding models and low-voltage winding models; Based on the material property parameters, the material parameters corresponding to the core foundation model and the winding model are determined, and the geometric model corresponding to the power transformer is obtained.

[0121] Optionally, in establishing the multiphysics coupling model, the multiphysics coupling model construction module 702 is further specifically used for: The electric field model, the magnetic field model, the acoustic field model, the temperature field model, and the structural force field model are coupled according to a preset multiphysics coupling relationship to obtain the multiphysics coupling model; The multiphysics coupling relationships include: magnetic-structure coupling, thermal-structure coupling, structure-acoustic field coupling, and electric-magnetic coupling. The magnetic-structure coupling relationship is used to couple the magnetic field model and the structural force field model; the thermal-structure coupling relationship is used to couple the temperature field model and the structural force field model; the structure-acoustic field coupling relationship is used to couple the structural force field model and the acoustic field model; and the electric-magnetic coupling relationship is used to couple the electric field model and the magnetic field model.

[0122] Optionally, in the process of fusing the geometric model with the multiphysics coupling model to obtain the target simulation model, the multiphysics coupling model construction module 702 is further specifically used for: The geometric model is meshed to obtain a meshed geometric model; the mesh shape includes at least one of the following: triangular, quadrilateral, and hexagonal; The meshed geometric model is imported into a preset finite element simulation environment, and the meshed geometric model is associated with the coupling equations corresponding to each physical model in the multiphysics coupling model to obtain the target simulation model; the preset finite element simulation environment is used to perform finite element analysis on the target simulation model.

[0123] Optionally, in the process of inputting a preset DC bias current into the target simulation model and performing finite element analysis on the target simulation model to obtain the vibration displacement distribution and sound pressure distribution, the simulation analysis module 703 is further specifically used for: An external circuit model is constructed; the external circuit model includes a left high-voltage circuit and a right low-voltage circuit; the left high-voltage circuit is used to provide the rated voltage; the right low-voltage circuit is used to maintain an open circuit; the external circuit model is used to simulate a DC bias state; The external circuit model is coupled to the target simulation model using the field circuit coupling method, and the preset DC bias current is input to the target simulation model. Finite element analysis is performed on the coupling equations of each physical field in the target simulation model to obtain the vibration displacement distribution and the sound pressure distribution.

[0124] Optionally, in determining the first weak point data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution, the first weak point calculation module 704 is further specifically used for: Based on the vibration displacement change distribution, the vibration displacement value of each of the multiple first position points is determined, resulting in multiple vibration displacement values; the first position points are pre-set monitoring points used to monitor the vibration effects. The multiple vibration displacement values ​​are compared with a preset vibration displacement threshold, and a first position point with a vibration displacement value greater than the preset vibration displacement threshold is selected to obtain at least one first position point. Determine the vibration displacement value corresponding to the at least one first position point to obtain at least one vibration displacement value; The first weak point data is determined based on the at least one first location point and the at least one vibration displacement value.

[0125] Optionally, in determining the second weak point data of the power transformer affected by the preset DC bias current based on the sound pressure distribution, the second weak point calculation module 705 is further specifically used for: Based on the sound pressure distribution, the sound pressure level data of each of the multiple second location points is determined to obtain multiple sound pressure level data; the second location points are pre-set monitoring points used to monitor the impact of noise; The multiple sound pressure level data are compared with a preset sound pressure level threshold, and second location points with sound pressure level data greater than the sound pressure level threshold are selected to obtain at least one second location point; Determine the sound pressure level data corresponding to the at least one second location point to obtain at least one sound pressure level data; The second weak point data is determined based on the at least one second location point and the at least one sound pressure level data.

[0126] The multi-physics coupling simulation analysis device 700 for power transformers described in this application can acquire transformer data of a power transformer; construct a geometric model corresponding to the power transformer based on the transformer data, and establish a multi-physics coupling model; fuse the geometric model and the multi-physics coupling model to obtain a target simulation model; input a preset DC bias current into the target simulation model, perform finite element analysis on the target simulation model, and obtain the vibration displacement change distribution and sound pressure distribution; determine the first weak position data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution; and determine the second weak position data of the power transformer affected by the preset DC bias current based on the sound pressure distribution. It can be seen that by establishing a multi-physics coupling model for analysis, accurate analysis and prediction of the vibration and noise characteristics of power transformers under DC bias environment can be achieved.

[0127] Please see Figure 13 , Figure 13 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include a processor, a memory, a communication interface, and one or more programs. The processor, memory, and communication interface can be interconnected via a bus. The one or more programs are stored in the memory and configured to be executed by the processor. In this embodiment, the programs include instructions for performing the following steps: Obtain transformer data for power transformers; the transformer data includes: transformer structural parameters and material property parameters; Based on the transformer data, a geometric model corresponding to the power transformer is constructed, and a multiphysics coupling model is established; the geometric model and the multiphysics coupling model are fused to obtain the target simulation model; the multiphysics coupling model includes: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model; A preset DC bias current is input into the target simulation model, and finite element analysis is performed on the target simulation model to obtain the vibration displacement change distribution and sound pressure distribution; the DC bias current is a current with a preset amplitude and a preset direction; Based on the vibration displacement change distribution, the first weak location data of the power transformer affected by the preset DC bias current is determined, and the first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. The second weak location data of the power transformer affected by the preset DC bias current is determined based on the sound pressure distribution. The second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution.

[0128] The electronic device described in this application can acquire transformer data of a power transformer; construct a geometric model corresponding to the power transformer based on the transformer data, and establish a multi-physics coupling model; fuse the geometric model and the multi-physics coupling model to obtain a target simulation model; input a preset DC bias current into the target simulation model, perform finite element analysis on the target simulation model, and obtain the vibration displacement change distribution and sound pressure distribution; determine the first weak point data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution; and determine the second weak point data of the power transformer affected by the preset DC bias current based on the sound pressure distribution. It can be seen that by establishing a multi-physics coupling model for analysis, accurate analysis and prediction of the vibration and noise characteristics of a power transformer under DC bias environment can be achieved.

[0129] This application also provides a computer-readable storage medium storing a computer program for electronic data interchange, which causes a computer to perform some or all of the steps of any of the methods described in the above method embodiments, wherein the computer includes an electronic device.

[0130] This application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps of any of the methods described in the above method embodiments. The computer program product may be a software installation package, and the computer may include an electronic device.

[0131] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM or random access memory (RAM), magnetic disks, or optical disks.

[0132] The steps of the methods or algorithms described in the embodiments of this application can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in RAM, flash memory, ROM, EPROM, electrically erasable programmable read-only memory (EEPROM), registers, hard disk, portable hard disk, read-only optical disk (CD-ROM), or any other form of storage medium well known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Furthermore, the ASIC can reside in a terminal device or management device. Alternatively, the processor and storage medium can exist as discrete components in the terminal device or management device.

[0133] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in the embodiments of this application can be implemented, in whole or in part, by software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. This computer program product includes one or more computer instructions. When these computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., digital video discs (DVDs)), or semiconductor media (e.g., solid-state disks (SSDs)).

[0134] The modules / units included in the various devices and products described in the above embodiments can be software modules / units, hardware modules / units, or a combination of both. For example, for devices and products applied to or integrated into a chip, all modules / units can be implemented using hardware methods such as circuits, or at least some modules / units can be implemented using software programs that run on a processor integrated within the chip, while the remaining (if any) modules / units can be implemented using hardware methods such as circuits. For devices and products applied to or integrated into a chip module, all modules / units can be implemented using hardware methods such as circuits. Different modules / units can be located in the same component (e.g., chip, circuit module, etc.) or different components of the chip module, or at least some modules / units can be implemented using hardware methods such as circuits. The implementation is achieved through a software program that runs on the processor integrated within the chip module. The remaining modules / units (if any) can be implemented using hardware methods such as circuits. For various devices and products applied to or integrated into terminal equipment, each of their modules / units can be implemented using hardware methods such as circuits. Different modules / units can be located in the same component (e.g., chip, circuit module, etc.) or different components within the terminal equipment. Alternatively, at least some modules / units can be implemented through a software program that runs on the processor integrated within the terminal equipment, while the remaining modules / units (if any) can be implemented using hardware methods such as circuits.

[0135] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above descriptions are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.

Claims

1. A multiphysics coupling simulation analysis method for power transformers, characterized in that, The method includes: Obtain transformer data for power transformers; the transformer data includes: transformer structural parameters and material property parameters; Based on the transformer data, a geometric model corresponding to the power transformer is constructed, and a multiphysics coupling model is established; the geometric model and the multiphysics coupling model are fused to obtain the target simulation model; the multiphysics coupling model includes: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model; A preset DC bias current is input into the target simulation model, and finite element analysis is performed on the target simulation model to obtain the vibration displacement change distribution and sound pressure distribution; the DC bias current is a current with a preset amplitude and a preset direction; Based on the vibration displacement change distribution, the first weak location data of the power transformer affected by the preset DC bias current is determined, and the first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. The second weak location data of the power transformer affected by the preset DC bias current is determined based on the sound pressure distribution. The second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution.

2. The method as described in claim 1, characterized in that, The transformer structural parameters include: core size data and winding size data; the construction of the geometric model corresponding to the power transformer based on the transformer data includes: Based on the core size data, construct a cylindrical core structure model and a rectangular yoke structure model; The cylindrical core structure model and the rectangular yoke structure model are merged into a core foundation model by Boolean union operation. Based on the winding size data, winding models are established on the cylindrical core structure of the iron core base model; the winding models include high-voltage winding models and low-voltage winding models; Based on the material property parameters, the material parameters corresponding to the core foundation model and the winding model are determined, and the geometric model corresponding to the power transformer is obtained.

3. The method as described in claim 2, characterized in that, The establishment of the multiphysics coupling model includes: The electric field model, the magnetic field model, the acoustic field model, the temperature field model, and the structural force field model are coupled according to a preset multiphysics coupling relationship to obtain the multiphysics coupling model; The multiphysics coupling relationships include: magnetic-structure coupling, thermal-structure coupling, structure-acoustic field coupling, and electric-magnetic coupling. The magnetic-structure coupling relationship is used to couple the magnetic field model and the structural force field model; the thermal-structure coupling relationship is used to couple the temperature field model and the structural force field model; the structure-acoustic field coupling relationship is used to couple the structural force field model and the acoustic field model; and the electric-magnetic coupling relationship is used to couple the electric field model and the magnetic field model.

4. The method as described in claim 3, characterized in that, The process of fusing the geometric model with the multiphysics coupling model to obtain the target simulation model includes: The geometric model is meshed to obtain a meshed geometric model; the mesh shape includes at least one of the following: triangular, quadrilateral, and hexagonal; The meshed geometric model is imported into a preset finite element simulation environment, and the meshed geometric model is associated with the coupling equations corresponding to each physical model in the multiphysics coupling model to obtain the target simulation model; the preset finite element simulation environment is used to perform finite element analysis on the target simulation model.

5. The method according to any one of claims 1-4, characterized in that, The process involves inputting a preset DC bias current into the target simulation model, performing finite element analysis on the target simulation model, and obtaining the vibration displacement distribution and sound pressure distribution, including: An external circuit model is constructed; the external circuit model includes a left high-voltage circuit and a right low-voltage circuit; the left high-voltage circuit is used to provide the rated voltage; the right low-voltage circuit is used to maintain an open circuit; the external circuit model is used to simulate a DC bias state; The external circuit model is coupled to the target simulation model using the field circuit coupling method, and the preset DC bias current is input to the target simulation model. Finite element analysis is performed on the coupling equations of each physical field in the target simulation model to obtain the vibration displacement distribution and the sound pressure distribution.

6. The method as described in claim 5, characterized in that, The determination of the first weak point data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution includes: Based on the vibration displacement change distribution, the vibration displacement value of each of the multiple first position points is determined, resulting in multiple vibration displacement values; the first position points are pre-set monitoring points used to monitor the vibration effects. The multiple vibration displacement values ​​are compared with a preset vibration displacement threshold, and a first position point with a vibration displacement value greater than the preset vibration displacement threshold is selected to obtain at least one first position point. Determine the vibration displacement value corresponding to the at least one first position point to obtain at least one vibration displacement value; The first weak point data is determined based on the at least one first location point and the at least one vibration displacement value.

7. The method as described in claim 5, characterized in that, The determination of the second weak point data of the power transformer affected by the preset DC bias current based on the sound pressure distribution includes: Based on the sound pressure distribution, the sound pressure level data of each of the multiple second location points is determined, resulting in multiple sound pressure level data; the second location points are pre-set monitoring points used to monitor the impact of noise. The multiple sound pressure level data are compared with a preset sound pressure level threshold, and second location points with sound pressure level data greater than the sound pressure level threshold are selected to obtain at least one second location point; Determine the sound pressure level data corresponding to the at least one second location point to obtain at least one sound pressure level data; The second weak point data is determined based on the at least one second location point and the at least one sound pressure level data.

8. A multiphysics coupling simulation analysis device for power transformers, characterized in that, The multiphysics coupling simulation analysis device for power transformers includes: a data acquisition module, a multiphysics coupling model construction module, a simulation analysis module, a first weak point calculation module, and a second weak point calculation module. The data acquisition module is used to acquire transformer data of the power transformer; the transformer data includes: transformer structural parameters and material property parameters; The multiphysics coupling model construction module is used to construct the geometric model corresponding to the power transformer based on the transformer data, and establish a multiphysics coupling model; the geometric model and the multiphysics coupling model are fused to obtain the target simulation model; the multiphysics coupling model includes: electric field model, magnetic field model, sound field model, temperature field model, and structural force field model; The simulation analysis module is used to input a preset DC bias current into the target simulation model, perform finite element analysis on the target simulation model, and obtain the vibration displacement distribution and sound pressure distribution; the DC bias current is a current with a preset amplitude and a preset direction; The first weak location calculation module is used to determine the first weak location data of the power transformer affected by the preset DC bias current based on the vibration displacement change distribution. The first weak location data is related to the location data of the vibration displacement value in the vibration displacement change distribution. The second weak location calculation module is used to determine the second weak location data of the power transformer affected by the preset DC bias current based on the sound pressure distribution. The second weak location data is related to the location data of the sound pressure level value in the sound pressure distribution.

9. An electronic device, characterized in that, include: Processor, memory, communication interface, and one or more programs; The one or more programs are stored in the memory and configured to be executed by the processor, the programs including instructions for performing the steps of the method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, the computer program including program instructions that, when executed by a processor, cause the processor to perform the method as described in any one of claims 1-7.

Images