Motor Temperature Field Calculation Method, Device, Vehicle, Medium and Program Product

Abstract

The present invention relates to the technical field of thermal management, and particularly relates to a method, device, vehicle, medium and program for calculating the temperature field of an electric motor. The method includes: obtaining the structural relationship of each component of the electric motor; establishing a one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the electric motor according to the structural relationship, and at the same time, establishing a coupling model according to the structural relationship; identifying the temperature rise values of each component of the electric motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the parameters that are mutually mapped and transmitted, so as to generate the coupling parameters of the parameter transfer coupling model; importing the coupling parameters of the parameter transfer coupling model into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the electric motor. Thereby, the problems in the related technology during the calculation of the temperature rise of the electric motor, such as the cumbersome calculation process, inaccurate results, difficulty in rapid iteration, and at the same time, difficulty in dealing with the temperature field of multiphase media and accurately calculating the temperature values at arbitrary positions, are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal management, and particularly to a method, device, vehicle, medium and program for calculating the temperature field of an electric motor. Background Art

[0002] Electric motors are increasingly widely used in the field of new energy vehicles, and their characteristics such as high efficiency and high power density are highly favored. However, due to the temperature sensitivity of the insulation materials and permanent magnets of electric motors, the problems of temperature rise and heat dissipation have become the key factors restricting their application and development. Although oil cooling technology has improved the cooling efficiency, it has also increased the difficulty of predicting the temperature rise of electric motors.

[0003] Currently, the calculation methods for the temperature rise of electric motors mainly include the one-dimensional thermal network method and the three-dimensional finite element method. However, although the three-dimensional finite element method can calculate the detailed temperature field of electric motor components, due to the complexity of the direct contact between the cooling oil of the electric motor and the windings and the internal air of the motor, the mesh generation is difficult and the calculation amount is large, making it difficult to meet the requirements of rapid iterative prediction. The one-dimensional thermal network method can quickly calculate the temperature value of the electric motor, but the modeling process is simple and cannot reflect the complex heat transfer characteristics inside the electric motor, resulting in large defects in the calculation results.

[0004] In the related art, the publication number CN116720305A proposes a method for calculating the internal temperature rise of an electric motor and its electronic control components in a new energy vehicle, which performs modeling and calculation through equivalent mass thermal resistance and fluidics software. Although the calculation efficiency is improved to a certain extent, it is impossible to calculate the temperature value at any position of the electric motor components and the temperature field of multiphase media. At the same time, the calculation process overly relies on empirical formulas, reducing the accuracy and reliability of the calculation results. Summary of the Invention

[0005] One of the purposes of the present invention is to provide a method for calculating the temperature field of an electric motor to solve the problems in the prior art that the calculation process is cumbersome, the results are inaccurate, it is difficult to perform rapid iteration, and it is also difficult to handle the temperature field of multiphase media and accurately calculate the temperature value at any position when calculating the temperature rise of the electric motor; the second purpose is to provide a device for calculating the temperature field of an electric motor; the third purpose is to provide a vehicle; the fourth purpose is to provide a computer-readable storage medium; the fifth purpose is to provide a computer program.

[0006] To achieve the above purposes, the technical solutions adopted by the present invention are as follows:

[0007] A method for calculating the temperature field of an electric motor, comprising the following steps: obtaining the structural relationship of each component of the electric motor; establishing a one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the electric motor according to the structural relationship, and establishing a coupling model according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, wherein the coupling model is used for the mutual mapping and transfer of parameters between the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model; identifying the temperature rise values of each component of the electric motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the mutually mapped and transferred parameters, and generating coupling parameters of the parameter transfer coupling model according to the temperature rise values and the heat transfer coefficient; importing the coupling parameters of the parameter transfer coupling model into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the electric motor.

[0008] According to the above technical means, in the embodiment of the present invention, by combining one-dimensional temperature simulation and three-dimensional heat flow simulation and establishing a coupling model for parameter transfer, it is possible to significantly improve the accuracy of temperature field prediction while ensuring efficient calculation, and at the same time effectively reduce the dependence on empirical formulas, making the calculation results more reliable. Among them, the one-dimensional temperature simulation model can quickly calculate the temperature rise values of each component of the electric motor, providing basic data for the overall thermal performance analysis; while the three-dimensional heat flow simulation model can detailly simulate the complex heat transfer process between multi-phase media inside the electric motor, so as to obtain a more realistic temperature field distribution. By establishing a coupling model, the mutual mapping and transfer of parameters between the one-dimensional temperature simulation and the three-dimensional heat flow simulation are realized, so as to obtain a more accurate and comprehensive temperature field prediction result, enabling it to cope with different design requirements and application scenarios. By importing the coupling parameters into the three-dimensional model, it becomes possible to calculate the temperature values at any position, which helps to understand the distribution of the internal thermal performance of the electric motor and provides strong support for optimizing the heat dissipation design and preventing thermal failures.

[0009] Further, the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-solid simulation model, wherein the finite element mesh model is a model obtained by macroscopically meshing each component of the electric motor, and the fluid-solid simulation model is a calculation model of the heat transfer coefficient between the cooling oil and the solid components of the electric motor.

[0010] According to the above technical means, in the embodiment of the present invention, the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-solid simulation model. Among them, the finite element mesh model is obtained by macroscopically meshing each component of the electric motor, which can finely describe the internal structural characteristics of the electric motor, so as to more accurately simulate the heat transfer process inside the electric motor; while the fluid-solid simulation model can calculate the heat transfer coefficient between the cooling oil and the solid components of the electric motor, and can accurately simulate the heat exchange process between the cooling oil and the solid components, providing key parameters for the overall temperature field prediction.

[0011] Further, a coupling model is established based on the structural relationship, the one-dimensional temperature simulation model, and the three-dimensional heat flow simulation model, further including: binding the grids of the finite element grid model to the boundary module of the one-dimensional temperature simulation model according to the structural relationship, and determining the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input conditions of the boundary module according to the structural relationship; establishing a coupling model based on the bound grids and boundary model and the mapping relationship.

[0012] According to the above technical means, in the embodiment of the present invention, the grids of the finite element grid model are bound to the boundary module of the one-dimensional temperature simulation model according to the structural relationship, ensuring that the boundary conditions in the one-dimensional temperature simulation model can be accurately mapped to the corresponding grids in the three-dimensional model, thereby achieving the consistency of the model in terms of boundary conditions. The one-dimensional temperature simulation model can provide accurate boundary conditions for the three-dimensional heat flow simulation model, enabling the three-dimensional model to more realistically simulate the heat transfer process inside the motor. At the same time, in the embodiment of the present invention, the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input conditions of the boundary module is also determined according to the structural relationship, ensuring that the heat transfer coefficient in the fluid-solid simulation model can be dynamically adjusted according to the boundary conditions of the one-dimensional temperature simulation model, thereby more accurately reflecting the heat exchange process between the cooling oil and the solid components.

[0013] Further, a one-dimensional temperature simulation model of the motor is established according to the structural relationship, including: obtaining the body models and dimensional parameters of the various components of the motor; establishing a one-dimensional temperature simulation model of the motor according to the body models, structural relationship, and dimensional parameters of the various components of the motor.

[0014] According to the above technical means, in the embodiment of the present invention, a one-dimensional temperature simulation model of the motor is established by obtaining the body models and dimensional parameters of the various components of the motor. According to the heat conduction relationship between the various components of the motor, it is convenient to quickly calculate the temperature rise values of the various components of the motor subsequently.

[0015] Further, the body models of the various components of the motor include a housing model, a stator model, a rotor model, a shaft model, and an oil circuit model, and the one-dimensional temperature simulation model includes a motor housing heat capacity module, a stator yoke heat capacity module, a stator tooth heat capacity module, a winding heat capacity module, a rotor heat capacity module, a permanent magnet heat capacity module, a shaft heat capacity module, and a cooling oil circuit.

[0016] Further, the stator iron loss, stator copper loss, and rotor iron loss are used as the heat sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model.

[0017] According to the above technical means, in the embodiment of the present invention, by taking the stator iron loss, stator copper loss, and rotor iron loss as the heat flux sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model, the heat generation of each component inside the motor during actual operation can be more accurately simulated. By taking the losses as the heat flux sources, the heat transfer path and heat dissipation process inside the motor can be analyzed, and then the thermal interaction and thermal balance state between the components of the motor can be evaluated, improving the thermal performance of the motor.

[0018] Further, before the one-dimensional temperature simulation model calculates the temperature rise values of each component of the motor and the heat transfer coefficient of the three-dimensional heat flux simulation model in identifying the parameters that are mutually mapped and transmitted, it further includes: identifying the current operating condition of the motor; solving the heat balance equation of the one-dimensional temperature simulation model under the current operating condition to obtain the temperature rise values of each component of the motor, where the heat balance equation is:

[0019]

[0020]

[0021]

[0022]

[0023] Among them, c 1i is the heat capacity of the node component, ρ 1i is the density of the node component, V 1i is the volume of the node component, is the temperature value of the node component, is the axial thermal conduction resistance of the node, is the radial thermal conduction resistance of the node, is the convective equivalent resistance of the node, Q k(k＝1～9) (t) is the heat flux of the node, and A is the contact area.

[0024] According to the above technical means, in the embodiment of the present invention, by identifying the current operating condition of the motor and solving the one-dimensional temperature simulation model based on this condition, the temperature rise of each component of the motor can be monitored in real time, which helps to evaluate the thermal performance and state of the motor during real-time operation, ensure the motor operates within a safe range, and by calculating the temperature rise values of each component, abnormal temperature rise situations can be detected in time, and the occurrence of faults can be warned in advance, thereby extending the service life of the motor.

[0025] Further, identifying the current operating condition of the motor includes: obtaining the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit of the motor, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit, and the motor temperature; determining the current operating condition based on the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit, and the motor temperature.

[0026] According to the above technical means, in the embodiment of the present invention, by obtaining the water temperature and water flow rate at the inlet and outlet of the coolant circuit, the efficiency of the coolant circulation and the heat exchange capacity can be evaluated, and the temperature and pressure at the inlet and outlet of the oil cooler in the cooling oil circuit can reflect the circulation state and cooling effect of the cooling oil in the oil circuit. Combining with the temperature data of the motor itself, a more comprehensive evaluation of the overall thermal state of the motor can be carried out, so as to accurately determine the current working condition of the motor.

[0027] Further, after the three-dimensional heat flow simulation model outputs the temperature field of the motor, it further includes: evaluating the risk points where the temperature value of the motor exceeds the preset value by using the temperature field of the motor.

[0028] According to the above technical means, in the embodiment of the present invention, by evaluating the risk points where the temperature value of the motor exceeds the preset value by using the temperature field of the motor, the risk points can be dynamically monitored and warned, and the temperature of the motor can be reduced in time to improve its performance and reliability.

[0029] A motor temperature field calculation device includes: an acquisition module for acquiring the structural relationship of each component of the motor; a building module for building a one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the motor according to the structural relationship, and building a coupling model according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, wherein the coupling model is used for the mutual mapping and transfer of parameters between the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model; a generation module for identifying the temperature rise values of each component of the motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the mutually mapped and transferred parameters, and generating coupling parameters of the parameter transfer coupling model according to the temperature rise values and the heat transfer coefficient; an output module for importing the coupling parameters of the parameter transfer coupling model into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the motor.

[0030] Further, the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-solid simulation model, wherein the finite element mesh model is a model obtained by macro-meshing each component of the motor, and the fluid-solid simulation model is a calculation model of the heat transfer coefficient between the cooling oil and the solid components of the motor.

[0031] Further, the building module is further used for: binding the mesh of the finite element mesh model with the boundary module of the one-dimensional temperature simulation model according to the structural relationship, and determining the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input conditions of the boundary module according to the structural relationship; building a coupling model according to the bound mesh and boundary model and the mapping relationship.

[0032] Further, the building module is further used for: acquiring the body model and size parameters of each component of the motor; building a one-dimensional temperature simulation model of the motor according to the body model, structural relationship and size parameters of each component of the motor.

[0033] Furthermore, the body models of the motor components include a housing model, a stator model, a rotor model, a shaft model, and an oil circuit model, and the one-dimensional temperature simulation model includes a motor housing heat capacity module, a stator yoke heat capacity module, a stator tooth heat capacity module, a winding heat capacity module, a rotor heat capacity module, a permanent magnet heat capacity module, a shaft heat capacity module, and a cooling oil circuit.

[0034] Furthermore, the stator iron loss, stator copper loss, and rotor iron loss are used as the heat flux sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model.

[0035] Furthermore, before the one-dimensional temperature simulation model calculates the temperature rise values of the motor components and the heat transfer coefficient of the three-dimensional heat flux simulation model in identifying the mutually mapped and transferred parameters, it further includes: an identification module for identifying the current operating condition of the motor; a calculation module for solving the heat balance equation of the one-dimensional temperature simulation model under the current operating condition to obtain the temperature rise values of the motor components, where the heat balance equation is:

[0036]

[0037]

[0038]

[0039]

[0040] where c 1i is the heat capacity of the node component, ρ 1i is the density of the node component, V 1i is the volume of the node component, is the temperature value of the node component, is the axial thermal conduction resistance of the node, is the radial thermal conduction resistance of the node, is the convective equivalent resistance of the node, Q k(k＝1～9) (t) is the heat flux of the node, and A is the contact area.

[0041] Furthermore, the identification module is further used for: obtaining the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit of the motor, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit, and the motor temperature; determining the current operating condition according to the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit, and the motor temperature.

[0042] Furthermore, the output module is further used for: evaluating the risk points where the temperature value of the motor exceeds the preset value by using the temperature field of the motor.

[0043] A vehicle, comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to implement a method for calculating the temperature field of an electric motor.

[0044] A computer-readable storage medium, on which a computer program is stored, and the program is executed by a processor to implement a method for calculating the temperature field of an electric motor.

[0045] A computer product, on which a computer program is stored, and when the computer program is executed, it is used to implement a method for calculating the temperature field of an electric motor.

[0046] Advantages of the present invention:

[0047] (1) In the embodiments of the present invention, by combining one-dimensional temperature simulation and three-dimensional heat flow simulation, and establishing a coupling model for parameter transfer, it is possible to significantly improve the accuracy of temperature field prediction while ensuring efficient calculation, and at the same time effectively reduce the dependence on empirical formulas, making the calculation results more reliable. Among them, the one-dimensional temperature simulation model can quickly calculate the temperature rise values of various components of the electric motor, providing basic data for the overall thermal performance analysis; while the three-dimensional heat flow simulation model can detailedly simulate the complex heat transfer process between multiple-phase media inside the electric motor, so as to obtain a more realistic temperature field distribution. By establishing a coupling model, the mutual mapping and transfer of parameters between the one-dimensional temperature simulation and the three-dimensional heat flow simulation are realized, so as to obtain a more accurate and comprehensive temperature field prediction result, enabling it to cope with different design requirements and application scenarios. By importing the coupling parameters into the three-dimensional model, it becomes possible to calculate the temperature values at any position, which helps to understand the distribution of the internal thermal performance of the electric motor and provides strong support for optimizing the heat dissipation design and preventing thermal failures;

[0048] (2) In the embodiments of the present invention, the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-structure simulation model. Among them, the finite element mesh model is obtained by macroscopically meshing each component of the electric motor, and can finely describe the internal structural characteristics of the electric motor, so as to more accurately simulate the heat transfer process inside the electric motor; while the fluid-structure simulation model can calculate the heat transfer coefficient between the cooling oil and the solid components of the electric motor, and can accurately simulate the heat exchange process between the cooling oil and the solid components, providing key parameters for the overall temperature field prediction;

[0049] (3) In the embodiment of the present invention, the grid of the finite element mesh model and the boundary module of the one-dimensional temperature simulation model are bound according to the structural relationship, ensuring that the boundary conditions in the one-dimensional temperature simulation model can be accurately mapped to the corresponding grids in the three-dimensional model, thereby achieving the consistency of the model in terms of boundary conditions. The one-dimensional temperature simulation model can provide accurate boundary conditions for the three-dimensional heat flow simulation model, enabling the three-dimensional model to more realistically simulate the heat transfer process inside the motor. At the same time, in the embodiment of the present invention, the mapping relationship between the heat transfer coefficient of the fluid-structure simulation model and the input conditions of the boundary module is also determined according to the structural relationship, ensuring that the heat transfer coefficient in the fluid-structure simulation model can be dynamically adjusted according to the boundary conditions of the one-dimensional temperature simulation model, thus more accurately reflecting the heat exchange process between the cooling oil and the solid components;

[0050] (4) In the embodiment of the present invention, by obtaining the body models and dimensional parameters of each component of the motor, a one-dimensional temperature simulation model of the motor is established. According to the heat conduction relationship between the components of the motor, it is convenient to quickly calculate the temperature rise values of each component of the motor in the subsequent process;

[0051] (5) In the embodiment of the present invention, by taking the stator iron loss, stator copper loss, and rotor iron loss as the heat sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model, the heat generation conditions of each component inside the motor during the actual working process can be more accurately simulated. By taking the losses as heat sources, the heat transfer path and heat dissipation process inside the motor can be analyzed, and then the thermal interaction and thermal balance states between the components of the motor can be evaluated to improve the thermal performance of the motor;

[0052] (6) In the embodiment of the present invention, by identifying the current working condition of the motor and solving the one-dimensional temperature simulation model based on this condition, the temperature rise conditions of each component of the motor can be monitored in real time, which helps to evaluate the thermal performance and state of the motor during real-time operation, ensure that the motor operates within a safe range, and by calculating the temperature rise values of each component, abnormal temperature rise conditions can be detected in time, and early warning of the occurrence of faults can be given, thereby extending the service life of the motor;

[0053] (7) In the embodiment of the present invention, by obtaining the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit, the efficiency and heat exchange capacity of the coolant circulation can be evaluated. The inlet and outlet temperatures and inlet and outlet pressures of the oil cooler in the cooling oil circuit can reflect the circulation state and cooling effect of the cooling oil in the oil circuit. Combining the temperature data of the motor itself, a more comprehensive evaluation of the overall thermal state of the motor can be carried out, thereby accurately determining the current working condition of the motor;

[0054] (8) In the embodiment of the present invention, the risk points where the temperature value of the motor exceeds the preset value are evaluated using the temperature field of the motor, and the risk points can be dynamically monitored and warned, and the temperature of the motor can be reduced in time to improve its performance and reliability.

[0055] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0056] Figure 1 Flow chart of the method for calculating the motor temperature field provided by an embodiment of the present invention;

[0057] Figure 2 Schematic diagram of the one-dimensional network heat capacity node calculation model provided by an embodiment of the present invention;

[0058] Figure 3 Schematic diagram of the motor relationship analysis provided by an embodiment of the present invention;

[0059] Figure 4 Flow chart of the method for calculating the motor temperature field provided by an embodiment of the present invention;

[0060] Figure 5 Schematic diagram of the global temperature field of the motor provided by an embodiment of the present invention;

[0061] Figure 6 Accuracy diagram of the motor test benchmark provided by an embodiment of the present invention;

[0062] Figure 7 Schematic diagram of the motor temperature field calculation device provided by an embodiment of the present invention;

[0063] Figure 8 Schematic diagram of the structure of the vehicle provided by an embodiment of the present invention.

[0064] Among them, 11-13, 91, 92 represent the heat capacity nodes of the motor housing; 21-23 represent the heat capacity nodes of the stator yoke; 31-33 represent the heat capacity nodes of the stator teeth; 41-45 represent the heat capacity nodes of the winding; 51-53 represent the heat capacity nodes of the rotor; 61-63 represent the heat capacity nodes of the permanent magnet; 71-75, 81-85 represent the heat capacity nodes of the shaft; "→" represents the convective thermal resistance R of the cooling oil circuit and its mutual relationship; h "-" represents the conductive thermal resistance R; λ C; ij represents the heat capacity node, i represents the first digital code of each heat capacity node, and j represents the second digital code of each heat capacity node. Detailed Embodiments

[0065] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for explaining the present invention, rather than limiting the protection scope of the present invention.

[0066] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0067] Motors, such as oil-cooled motors, etc., are increasingly used in the field of new energy vehicles due to their high efficiency, high power density, high torque density, and high control precision. However, because the insulating materials and permanent magnets of the motor are sensitive to temperature, the working performance and lifespan of the motor will be reduced, making the temperature rise and heat dissipation problems the key factors restricting its further development.

[0068] Oil cooling changes the indirect heat transfer of water cooling to direct contact between oil and components, greatly improving the cooling efficiency. However, at the same time, it increases the difficulty and accuracy of motor temperature rise prediction. Therefore, how to quickly and accurately predict and calculate the temperature rise of the motor and its components has become an urgent problem for current developers to solve.

[0069] Currently, the calculation methods for motor temperature rise mainly include the one-dimensional thermal network method and the three-dimensional finite element method, but each method has its limitations. The finite element method can accurately calculate the temperature field values of motor components, but the special structure of the motor makes the mesh generation difficult and the calculation amount huge, making it difficult to meet the development requirements of rapid iteration. The thermal network method, although fast in calculation speed and having a certain accuracy, has an overly simplified modeling process and cannot reflect the actual temperature distribution of motor components, resulting in large errors in the calculation results.

[0070] In the related art, a method for calculating the internal temperature rise of a new energy vehicle motor and its electronic control components is proposed in the publication number CN116720305A. It attempts to model the motor and components by using an equivalent mass thermal resistance similar to a thermal network, calculates the heat generation of macroscopic components through a fluidics software, applies the component heat generation to an equivalent mass block to obtain the temperature of equivalent units through one-dimensional calculation, and proposes an empirical formula when calculating the temperature, and uses this empirical formula to correct the temperature. There are the following problems with this method: (1) It is impossible to calculate the temperature values at any position of the entire motor component, highly dependent on the number of mass thermal resistance blocks, and it is difficult to guarantee the accuracy; (2) It is difficult to calculate the temperature field of multi-phase media existing inside the motor, and multi-phase fluid media play a decisive role in the motor heat transfer temperature calculation; (3) The calculation process depends on the empirical formula, calibrates the thermal resistance between mass blocks by using direct measured temperature values, and the conduction thermal resistance and convection thermal resistance cannot be directly calculated, which affects the accuracy of the calculation results to a certain extent.

[0071] Specifically, Figure 1 FIG. is a schematic flow chart of a method for calculating the motor temperature field provided by an embodiment of the present invention.

[0072] As Figure 1 shown, the method for calculating the motor temperature field includes the following steps:

[0073] In step S101, the structural relationships of the various components of the motor are obtained.

[0074] Among them, the structural relationship may be the relative positions and connection methods between the various components of the motor. For example, the relationship between the stator and the rotor, the relationship between the winding and the iron core, etc. The motor in the embodiment of the present application may be an oil-cooled motor, etc., which can be selected according to the actual situation and is not specifically limited.

[0075] It can be understood that by obtaining the structural relationships of the various components of the motor in the embodiment of the present invention, data support is provided for establishing an accurate temperature simulation model, which helps to accurately predict and evaluate the temperature field distribution of the motor, and provides strong technical support for the optimal design and operation of the motor.

[0076] In step S102, a one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the motor are established according to the structural relationships, and a coupling model is established according to the structural relationships, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, where the coupling model is used for the mutual mapping and transfer of parameters between the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model.

[0077] Among them, as Figure 2As shown, the one-dimensional temperature simulation model may include the motor housing heat capacity modules 11-13, 91, 92, the stator yoke heat capacity modules 21-23, the stator tooth heat capacity modules 31-33, the winding heat capacity modules 41-45, the rotor heat capacity modules 51-53, the permanent magnet heat capacity modules 61-63, the shaft heat capacity modules 71-75, 81-85, and the cooling oil circuit. The three-dimensional heat flow simulation model may include a finite element mesh model and a fluid-structure simulation model. Among them, the finite element mesh model is a model obtained by macro-meshing each component of the motor, and the fluid-structure simulation model is a calculation model for the heat transfer coefficient between the cooling oil of the motor and the solid components.

[0078] It can be understood that in the embodiments of the present invention, by combining one-dimensional temperature simulation and three-dimensional heat flow simulation and establishing a coupling model for parameter transfer, it is possible to significantly improve the accuracy of temperature field prediction while ensuring efficient calculation, and at the same time effectively reduce the dependence on empirical formulas, making the calculation results more reliable. Among them, the one-dimensional temperature simulation model can quickly calculate the temperature rise values of each component of the motor, providing basic data for the overall thermal performance analysis; while the three-dimensional heat flow simulation model can detailedly simulate the complex heat transfer process between multiple phases of the medium inside the motor, so as to obtain a more realistic temperature field distribution. By establishing a coupling model, the mutual mapping transfer of parameters between the one-dimensional temperature simulation and the three-dimensional heat flow simulation is realized, so as to obtain a more accurate and comprehensive temperature field prediction result, enabling it to cope with different design requirements and application scenarios.

[0079] It should be noted that the finite element mesh model is obtained by macro-meshing each component of the motor, which can finely describe the internal structural characteristics of the motor, so as to more accurately simulate the heat transfer process inside the motor; while the fluid-structure simulation model can calculate the heat transfer coefficient between the cooling oil of the motor and the solid components, and can accurately simulate the heat exchange process between the cooling oil and the solid components, providing key parameters for the overall temperature field prediction.

[0080] In the embodiments of the present invention, a coupling model is established according to the structural relationship, the one-dimensional temperature simulation model, and the three-dimensional heat flow simulation model, and further includes: binding the grids of the finite element mesh model to the boundary module of the one-dimensional temperature simulation model according to the structural relationship, and determining the mapping relationship between the heat transfer coefficient of the fluid-structure simulation model and the input conditions of the boundary module according to the structural relationship; establishing a coupling model according to the bound grids and the boundary model and the mapping relationship.

[0081] Among them, the boundary module may be a part of the one-dimensional temperature simulation model, representing the interface between the model and the external environment.

[0082] It can be understood that in the embodiments of the present invention, the grid of the finite element mesh model is bound to the boundary module of the one-dimensional temperature simulation model according to the structural relationship, ensuring that the boundary conditions in the one-dimensional temperature simulation model can be accurately mapped to the corresponding grids in the three-dimensional model, thereby achieving the consistency of the model in terms of boundary conditions. The one-dimensional temperature simulation model can provide accurate boundary conditions for the three-dimensional heat flow simulation model, enabling the three-dimensional model to more realistically simulate the heat transfer process inside the motor. At the same time, in the embodiments of the present invention, the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input conditions of the boundary module is determined according to the structural relationship, ensuring that the heat transfer coefficient in the fluid-solid simulation model can be dynamically adjusted according to the boundary conditions of the one-dimensional temperature simulation model, so as to more accurately reflect the heat exchange process between the cooling oil and the solid components.

[0083] In the embodiments of the present invention, a one-dimensional temperature simulation model of the motor is established according to the structural relationship, including: obtaining the body models and dimensional parameters of each component of the motor; establishing a one-dimensional temperature simulation model of the motor according to the body models, structural relationship and dimensional parameters of each component of the motor.

[0084] Among them, the body models of each component of the motor may include a housing model, a stator model, a rotor model, a shaft model and an oil circuit model, and the dimensional parameters may refer to the specific dimensional data of each component, such as length, width, height, diameter, etc.

[0085] It can be understood that in the embodiments of the present invention, by obtaining the body models and dimensional parameters of each component of the motor, a one-dimensional temperature simulation model of the motor is established, which is convenient for quickly calculating the temperature rise values of each component of the motor according to the heat conduction relationship between each component of the motor.

[0086] For example, the dimensional structure and relationship of the motor three-dimensional digital model are analyzed, and the relationship between the analyzed motor components and the oil circuit is as Figure 3 shown. The analyzed structural model includes a housing model, a stator model, a rotor model, a shaft model and an oil circuit model.

[0087] In the embodiments of the present invention, the stator iron loss, stator copper loss and rotor iron loss are used as the heat sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model.

[0088] Among them, the stator iron loss may be the energy loss generated in the stator core of the motor due to the change of the magnetic field, the stator copper loss may be the resistance loss generated in the stator winding of the motor due to the current flowing through the conductor, the rotor iron loss may be the energy loss generated in the rotor core of the motor due to the change of the magnetic field, and the heat source may be the source of heat generation.

[0089] It can be understood that in the embodiments of the present invention, by taking the stator iron loss, stator copper loss, and rotor iron loss as the heat sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model, the heat generation of each component inside the motor during actual operation can be more accurately simulated. By taking the losses as heat sources, the heat transfer path and heat dissipation process inside the motor can be analyzed, and thus the thermal interaction and thermal balance state between the components of the motor can be evaluated, improving the thermal performance of the motor.

[0090] In step S103, identify the temperature rise values of each component of the motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the mutually mapped and transferred parameters, and generate the coupling parameters of the parameter transfer coupling model based on the temperature rise values and the heat transfer coefficient.

[0091] Among them, the temperature rise value can be the temperature change amount of each component of the motor calculated by the one-dimensional temperature simulation model, the heat transfer coefficient can be the parameter used to describe the heat transfer efficiency between the fluid and the solid in the three-dimensional heat flow simulation model, and the coupling parameter can be the common parameter used to connect the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model in the parameter transfer coupling model.

[0092] It can be understood that the temperature rise values of each component of the motor calculated by the one-dimensional temperature simulation model in the embodiments of the present invention reflect the temperature changes of each component of the motor under specific working conditions, and the heat transfer coefficient of the three-dimensional heat flow simulation model reflects the heat exchange efficiency between the cooling oil and the motor components. By accurately calculating the heat transfer coefficient, it helps to more precisely simulate the heat transfer process inside the motor, thereby obtaining a more realistic temperature field distribution. Generating the coupling parameters of the parameter transfer coupling model based on the temperature rise values and the heat transfer coefficient can achieve data sharing and mutual supplementation between the one-dimensional temperature simulation and the three-dimensional heat flow simulation, not only considering the overall thermal performance of the motor but also simulating the heat transfer process inside the motor. By continuously adjusting and optimizing the coupling parameters, more accurate and comprehensive temperature field prediction results can be obtained.

[0093] In the embodiments of the present invention, before identifying the temperature rise values of each component of the motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the mutually mapped and transferred parameters, it further includes: identifying the current working condition of the motor; solving the heat balance equation of the one-dimensional temperature simulation model under the current working condition to obtain the temperature rise values of each component of the motor, where the heat balance equation is:

[0094]

[0095]

[0096]

[0097]

[0098] Among them, c 1i is the heat capacity of the node component, ρ 1i is the density of the node component, V 1i is the volume of the node component, is the temperature value of the node component, is the axial thermal conduction resistance of the node, is the radial thermal conduction resistance of the node, is the convective equivalent thermal resistance of the node, Q k(k＝1～9) (t) is the heat flux of the node, and A is the contact area.

[0099] It can be understood that in the embodiments of the present invention, by identifying the current working condition of the motor and solving the one-dimensional temperature simulation model based on this working condition, the temperature rise of each component of the motor can be monitored in real time, which helps to evaluate the thermal performance and state of the motor during real-time operation, ensure that the motor operates within a safe range, and by calculating the temperature rise values of each component, abnormal temperature rise situations can be detected in time, and the occurrence of faults can be warned in advance, thereby prolonging the service life of the motor.

[0100] In the embodiments of the present invention, identifying the current working condition of the motor includes: obtaining the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit of the motor, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit, and the motor temperature; determining the current working condition according to the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit, and the motor temperature.

[0101] Among them, the coolant circuit can be the path through which the coolant circulates in the cooling system, the inlet and outlet water temperatures can be the temperatures of the coolant at the inlet and outlet of the coolant circuit. Among them, the inlet water temperature can be the temperature when the coolant starts to circulate, the outlet water temperature can be the temperature of the coolant after passing through the heat dissipation component, the inlet and outlet water flow rates can be the flow rates of the coolant at the inlet and outlet of the coolant circuit, the inlet and outlet temperatures of the oil cooler can be the temperatures of the cooling oil at the inlet and outlet of the oil cooler. Among them, the inlet temperature can be the temperature when the cooling oil starts to enter the oil cooler, the outlet temperature can be the temperature of the cooling oil after heat dissipation through the oil cooler, the inlet and outlet pressures can be the pressures of the cooling oil at the inlet and outlet of the oil cooler, and the motor temperature can be the temperature of the motor during operation.

[0102] It can be understood that in the embodiments of the present invention, by obtaining the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit, the efficiency and heat exchange capacity of the coolant circulation can be evaluated, and the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler of the cooling oil circuit can reflect the circulation state and cooling effect of the cooling oil in the oil circuit. Combining the temperature data of the motor itself, a more comprehensive evaluation of the overall thermal state of the motor can be carried out, so as to accurately determine the current working condition of the motor.

[0103] In step S104, the coupling parameters of the parameter transfer coupling model are imported into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the motor.

[0104] Among them, the temperature field of the motor can be the temperature distribution of each internal component of the motor during operation and its change over time.

[0105] It can be understood that in the embodiment of the present invention, by importing the coupling parameters into the three-dimensional model, it becomes possible to calculate the temperature values at any position, which helps to understand the distribution of the internal thermal performance of the motor, provides strong support for optimizing the heat dissipation design and preventing thermal failures, and improves the accuracy and reliability of the temperature field prediction.

[0106] In the embodiment of the present invention, after the three-dimensional heat flow simulation model outputs the temperature field of the motor, it further includes: evaluating the risk points where the temperature values of the motor exceed the preset values by using the temperature field of the motor.

[0107] Among them, the preset value can be a temperature safety threshold determined according to factors such as the design specifications, material characteristics, and working environment of the motor, and the risk points can be the motor components or regions where the temperature values may exceed the preset values.

[0108] It can be understood that in the embodiment of the present invention, by using the temperature field of the motor to evaluate the risk points where the temperature values of the motor exceed the preset values, the risk points can be dynamically monitored and warned, the temperature of the motor can be reduced in time, and its performance and reliability can be improved.

[0109] According to the method for calculating the temperature field of the motor proposed in the embodiment of the present invention, by combining one-dimensional temperature simulation and three-dimensional heat flow simulation, and establishing a coupling model for parameter transfer, while ensuring efficient calculation, the accuracy of the temperature field prediction is significantly improved, and at the same time, the dependence on empirical formulas is effectively reduced, making the calculation results more reliable. Among them, the one-dimensional temperature simulation model can quickly calculate the temperature rise values of each component of the motor and provide basic data for the overall thermal performance analysis; while the three-dimensional heat flow simulation model can detail the complex heat transfer process between the multiphase media inside the motor, so as to obtain a more realistic temperature field distribution. By establishing a coupling model, the mutual mapping transfer of parameters between the one-dimensional temperature simulation and the three-dimensional heat flow simulation is realized, so as to obtain a more accurate and comprehensive temperature field prediction result, enabling it to cope with different design requirements and application scenarios. By importing the coupling parameters into the three-dimensional model, it becomes possible to calculate the temperature values at any position, which helps to understand the distribution of the internal thermal performance of the motor and provides strong support for optimizing the heat dissipation design and preventing thermal failures. Thus, the problems in the prior art of cumbersome calculation process, inaccurate results, difficult to quickly iterate, and difficult to handle the temperature field of multiphase media and accurately calculate the temperature values at any position when calculating the temperature rise of the motor are solved.

[0110] The following will specifically elaborate on the method for calculating the motor temperature field through a specific embodiment. As Figure 4 shown, taking a certain motor project of a new energy vehicle as an example, where the rated torque is 75 N·m, the temperature rise and temperature field of the motor are calculated and compared with the test values for accuracy. The calculation method includes the following steps:

[0111] S1. Analyze the basic structure model of the new energy vehicle motor and establish its relationship model; among them, as Figure 3 shown, the basic structure model can include the housing structure model, stator structure model, rotor structure model, shaft structure model, magnetic steel structure model, and oil circuit structure model in the motor body structure; perform dimensional measurement and relationship definition on each structure model. The analyzed motor relationship, as Figure 3 shown, each structure model of the motor is interrelated in the relationship model and jointly constitutes the working system of the motor;

[0112] S2. Establish a three-dimensional thermal fluid simulation model of the motor; the three-dimensional thermal fluid simulation model is based on a meshed finite element grid model and a fluid-structure simulation model based on the moving semi-implicit method; among them, the finite element grid model is the macroscopic finite element grid model of each component of the motor, and the fluid-structure simulation model based on the moving particle semi-implicit method is the simulation model for heat transfer and fluid dynamics calculation between the cooling oil and the solid components of the motor;

[0113] S3. As Figure 2 shown, establish a one-dimensional grid heat capacity node calculation model of the motor through the relationship model; among them, the one-dimensional grid heat capacity node simulation model includes discrete heat capacity modules of each component of the motor, heat conduction modules between heat capacity units divided from the same component, heat conduction thermal resistance modules between heat capacity units of different components, internal gas modules, oil circuit flow modules, convection modules between the solid heat capacity module and the oil circuit flow module, and heat transfer relationship logic modules between each node module;

[0114] S4. Bind the boundary nodes of the one-dimensional grid heat capacity node calculation model to the grids in the three-dimensional thermal fluid simulation model; among them, the boundary binding is to realize the mapping transfer of the heat transfer coefficient in the three-dimensional thermal fluid calculation to the one-dimensional heat capacity node boundary; the mapping transfer means extracting the heat transfer coefficient from the results of the thermal fluid calculation model and transferring it to the heat capacity node boundary as an input condition;

[0115] It should be noted that the boundary binding can include the binding of the core heat capacity nodes completed in S1 to the surface boundary of the finite element model established in S2, and the mapping binding of the convective thermal resistance R h and the heat transfer coefficient of the fluid-structure model. Among them, the core heat capacity nodes can be the stator yoke heat capacity nodes 21-23, stator tooth heat capacity nodes 31-33, winding heat capacity nodes 41-45, and rotor heat capacity nodes 51-53.

[0116] S5. Establish an overall parameter transfer coupling model by performing coupled parameter transfer between the three-dimensional motor thermal-fluid simulation model and the one-dimensional heat capacity node simulation model; the parameter transfer coupling model enables real-time communication between the calculation results of the thermal-fluid simulation model and the corresponding components of the one-dimensional heat capacity node model, with each serving as the boundary input condition and result output condition; among them, the coupling parameters include the heat transfer coefficient mapping transfer in S4, and also include the output of the calculation results from the one-dimensional heat capacity node model and their import into the three-dimensional thermal-fluid calculation model as the required full-local component temperature field caused by the internal differential heat conduction conditions of the motor components.

[0117] S6. Apply the stator loss Qs and the rotor loss Qr as heat sources to the core heat capacity nodes 21 to 53 as shown in Figure 2 to complete the initialization definition of the heat capacity nodes.

[0118] S7. Further, use the required calculation conditions as boundary conditions and apply them as input conditions to the one-dimensional heat capacity node calculation model; the required calculation conditions can be any conditions or specific conditions.

[0119] S8. Abstract and solve the heat balance equation of the motor one-dimensional grid heat capacity node calculation model. The abstracted and solved relationship is as follows:

[0120]

[0121]

[0122]

[0123]

[0124] Among them, c 1i is the heat capacity of the node component, ρ 1i is the density of the node component, V 1i is the volume of the node component, is the temperature value of the node component, is the axial heat conduction thermal resistance of the node, is the radial heat conduction thermal resistance of the node, is the convective equivalent thermal resistance of the node, Q k(k＝1～9) (t) is the heat flux of the node, and A is the contact area.

[0125] The heat transfer coefficient can be mapped from S4 and calculated as follows:

[0126]

[0127] Among them, R zx is the axial between nodes, R JX is the radial between nodes, Rh is the convective heat transfer resistance; is the temperature rise of the node; Q is the heat of the node; δ is the equivalent distance between nodes; λ is the thermal conductivity of the component corresponding to the node; A is the contact area; r 2 and r 1 are the radial radii; l is the axial length of the component; h is the convective heat transfer coefficient.

[0128] After the solution is completed, the heats Qi on the one-dimensional heat capacity nodes will be obtained;

[0129] S9. The equilibrium heat Qi calculated by the one-dimensional network heat capacity node calculation model will be fed back by S5 to the three-dimensional component heat model for calculating the overall and local temperature field distributions, and finally all the temperature field scalar distributions of the component will be obtained, as Figure 5 shown.

[0130] S10. Further, the temperature field scalar distribution fed back by the calculation of S9 is used to judge whether the temperature value at any position of any component of the motor is a over-temperature risk point; among them, the judgment of the risk point varies with the temperature resistance of the motor materials with different powers;

[0131] S11. If the risk points in the calculated result temperature scalar diagram are unacceptable, the motor design scheme is adjusted or optimized, and the process returns to S1 for cyclic calculation and analysis again; otherwise, the calculation accuracy is verified, and a benchmark test is carried out for the calculation result, and the test result is as Figure 6 shown.

[0132] Secondly, a motor temperature field calculation device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0133] Figure 7 is a block diagram of the motor temperature field calculation device according to an embodiment of the present invention.

[0134] As Figure 7 shown, the motor temperature field calculation device 10 includes: an acquisition module 100, a construction module 200, a generation module 300, and an output module 400.

[0135] Among them, the acquisition module 100 is used to acquire the structural relationship of each component of the motor; the establishment module 200 is used to establish a one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the motor according to the structural relationship, and establish a coupling model according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, wherein the coupling model is used for the mutual mapping and transfer of parameters between the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model; the generation module 300 is used to identify the temperature rise values of each component of the motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the mutually mapped and transferred parameters, and generate the coupling parameters of the parameter transfer coupling model according to the temperature rise values and the heat transfer coefficient; the output module 400 is used to import the coupling parameters of the parameter transfer coupling model into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the motor.

[0136] In the embodiment of the present invention, the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-solid simulation model, wherein the finite element mesh model is a model obtained by macro-meshing each component of the motor, and the fluid-solid simulation model is a calculation model of the heat transfer coefficient between the cooling oil and the solid components of the motor.

[0137] In the embodiment of the present invention, the establishment module 200 is further used to: bind the grid of the finite element mesh model and the boundary module of the one-dimensional temperature simulation model according to the structural relationship, and determine the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input conditions of the boundary module according to the structural relationship; establish a coupling model according to the bound grid and boundary model and the mapping relationship.

[0138] In the embodiment of the present invention, the establishment module 200 is further used to: acquire the body model and size parameters of each component of the motor; establish a one-dimensional temperature simulation model of the motor according to the body model, structural relationship and size parameters of each component of the motor.

[0139] In the embodiment of the present invention, the body model of each component of the motor includes a housing model, a stator model, a rotor model, a shaft model and an oil circuit model, and the one-dimensional temperature simulation model includes a motor housing heat capacity module, a stator yoke heat capacity module, a stator tooth heat capacity module, a winding heat capacity module, a rotor heat capacity module, a permanent magnet heat capacity module, a shaft heat capacity module and a cooling oil circuit.

[0140] In the embodiment of the present invention, the stator iron loss, stator copper loss and rotor iron loss are used as the heat sources of the corresponding heat capacity modules in the one-dimensional temperature simulation model.

[0141] In the embodiment of the present invention, before identifying the temperature rise values of each component of the motor calculated by the one-dimensional temperature simulation model and the heat transfer coefficient of the three-dimensional heat flow simulation model among the mutually mapped and transferred parameters, it further includes: an identification module, used to identify the current working condition of the motor; a calculation module, used to solve the heat balance equation of the one-dimensional temperature simulation model under the current working condition to obtain the temperature rise values of each component of the motor, wherein the heat balance equation is:

[0142]

[0143]

[0144]

[0145]

[0146] Among them, c 1i is the heat capacity of the node component, ρ 1i is the density of the node component, V 1i is the volume of the node component, is the temperature value of the node component, is the axial thermal resistance of the node, is the radial thermal resistance of the node, is the convective equivalent thermal resistance of the node, Q k(k＝1～9) (t) is the heat flux of the node, and A is the contact area.

[0147] In the embodiment of the present invention, the recognition module is further configured to: obtain the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit of the motor, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler in the oil cooling circuit, and the motor temperature; determine the current working condition according to the inlet and outlet water temperatures and inlet and outlet water flow rates of the coolant circuit, the inlet and outlet temperatures and inlet and outlet pressures of the oil cooler in the oil cooling circuit, and the motor temperature.

[0148] In the embodiment of the present invention, the output module 400 is further configured to: evaluate the risk points where the temperature value of the motor exceeds the preset value by using the temperature field of the motor.

[0149] It should be noted that the foregoing explanation of the embodiment of the motor temperature field calculation method is also applicable to the motor temperature field calculation device of this embodiment, and will not be elaborated here.

[0150] The motor temperature field calculation device proposed according to the embodiments of the present invention combines one-dimensional temperature simulation and three-dimensional heat flow simulation, and establishes a coupling model for parameter transfer, achieving significant improvement in the accuracy of temperature field prediction while ensuring efficient calculation, effectively reducing the dependence on empirical formulas, and making the calculation results more reliable. Among them, the one-dimensional temperature simulation model can quickly calculate the temperature rise values of each component of the motor, providing basic data for the overall thermal performance analysis; while the three-dimensional heat flow simulation model can detailly simulate the complex heat transfer process between multi-phase media inside the motor, so as to obtain a more realistic temperature field distribution. By establishing a coupling model, the mutual mapping transfer of parameters between the one-dimensional temperature simulation and the three-dimensional heat flow simulation is realized, thus obtaining a more accurate and comprehensive temperature field prediction result, enabling it to cope with different design requirements and application scenarios. By importing the coupling parameters into the three-dimensional model, the calculation of temperature values at any position becomes possible, which helps to understand the distribution of the internal thermal performance of the motor and provides strong support for optimizing the heat dissipation design and preventing thermal failures. Thus, the problems in the prior art in calculating the motor temperature rise, such as the cumbersome calculation process, inaccurate results, difficulty in rapid iteration, and difficulty in dealing with the temperature field of multi-phase media and accurately calculating the temperature values at any position, are solved.

[0151] Figure 8 The structure diagram of the vehicle provided by the embodiment of the present invention. The vehicle may include:

[0152] A memory 801, a processor 802, and a computer program stored on the memory 801 and executable on the processor 802.

[0153] When the processor 802 executes the program, it implements the motor temperature field calculation method provided in the above embodiment.

[0154] Furthermore, the vehicle further includes:

[0155] A communication interface 803 for communication between the memory 801 and the processor 802.

[0156] The memory 801 is used to store a computer program executable on the processor 802.

[0157] The memory 801 may include a high-speed RAM (Random Access Memory) memory, and may also include a non-volatile memory, such as at least one disk memory.

[0158] If the memory 801, the processor 802, and the communication interface 803 are implemented independently, the communication interface 803, the memory 801, and the processor 802 can be interconnected through a bus and communicate with each other. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, an EISA (Extended Industry Standard Architecture) bus, or the like. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 8 only a thick line is used in Figure 8 , but it does not mean that there is only one bus or one type of bus.

[0159] Optionally, in a specific implementation, if the memory 801, the processor 802, and the communication interface 803 are integrated on a single chip, the memory 801, the processor 802, and the communication interface 803 can communicate with each other through an internal interface.

[0160] The processor 802 may be a CPU (Central Processing Unit), or an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0161] The embodiments of the present invention also provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the above-mentioned motor temperature field calculation method is implemented.

[0162] The embodiments of the present invention also provide a computer program product, on which a computer program is stored, and when the computer program is executed, the above-mentioned motor temperature field calculation method is implemented.

[0163] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or N embodiments or examples. In addition, without conflict, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples.

[0164] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0165] Any process or method description shown in a flowchart or described otherwise herein may be understood to represent a module, segment, or portion of code including one or N executable instructions for implementing a customized logical function or process, and the scope of the preferred embodiments of the present invention includes additional implementations, where the functions may be executed in a substantially simultaneous manner or in an order opposite to that shown or discussed, according to the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0166] It should be understood that various parts of the present invention may be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods may be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following techniques well known in the art may be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays, field programmable gate arrays, etc.

[0167] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0168] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for calculating the temperature field of a motor, characterized in that: The following steps are involved: Obtain the structural relationship of each motor component; A one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the motor are established according to the structural relationship, and a coupling model is established according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, wherein the coupling model is used for mutual mapping and transfer of parameters between the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-solid simulation model, the finite element mesh model is a model obtained by macroscopic meshing of various components of the motor, and the fluid-solid simulation model is a calculation model of the heat transfer coefficient of the cooling oil and solid components of the motor; the establishment of the coupling model according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model also includes: binding the mesh of the finite element mesh model and the boundary module of the one-dimensional temperature simulation model according to the structural relationship, and determining the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input condition of the boundary module according to the structural relationship; establishing the coupling model according to the bound mesh and boundary model and the mapping relationship; The one-dimensional temperature simulation model in the mutually mapped and transferred parameters is identified to calculate the temperature rise values ​​of the motor components and the heat transfer coefficient of the three-dimensional heat flow simulation model, and the coupling parameters of the parameter transfer coupling model are generated according to the temperature rise values ​​and the heat transfer coefficient; The coupling parameters of the parameter transfer coupling model are imported into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the motor.

2. The method for calculating the motor temperature field according to claim 1, characterized in that: The step of establishing a one-dimensional temperature simulation model of the motor according to the structural relationship comprises: Obtain the main body model and size parameters of each component of the motor; A one-dimensional temperature simulation model of the motor is established according to the body model, structural relationship and size parameters of each component of the motor.

3. The method for calculating the motor temperature field according to claim 2, characterized in that: The main body models of the motor components include a shell model, a stator model, a rotor model, a shaft model and an oil circuit model, and the one-dimensional temperature simulation model includes a motor shell heat capacity module, a stator choke heat capacity module, a stator tooth heat capacity module, a winding heat capacity module, a rotor heat capacity module, a magnetic steel heat capacity module, a shaft heat capacity module and a cooling oil circuit.

4. The method for calculating the motor temperature field according to claim 3, characterized in that: The stator iron loss, stator copper loss and rotor iron loss are used as heat flow sources corresponding to the hot melt module in the one-dimensional temperature simulation model.

5. The method for calculating the motor temperature field according to claim 1 or 2, characterized in that: Before the one-dimensional temperature simulation model calculates the temperature rise values ​​of the motor components and the heat transfer coefficient of the three-dimensional heat flow simulation model in the parameters of the mutually mapped transmission, the method further includes: identifying a current operating condition of the motor; Under the current working condition, the heat balance equation of the one-dimensional temperature simulation model is solved to obtain the temperature rise value of each component of the motor, wherein the heat balance equation is: in, is the heat capacity of the node component, is the density of the node components, is the volume of the node component, is the temperature value of the node component, is the axial thermal resistance of the node, is the radial thermal resistance of the node, is the convection equivalent thermal resistance of the node, is the heat flux at the node, is the contact area.

6. The method for calculating the motor temperature field according to claim 5, characterized in that: The identifying the current operating condition of the motor includes: Obtain the inlet and outlet water temperature and inlet and outlet water flow rate of the coolant circuit of the motor, the inlet and outlet temperature and inlet and outlet pressure of the oil cooler of the cooling oil circuit, and the motor temperature; The current operating condition is determined according to the inlet and outlet water temperature and inlet and outlet water flow rate of the coolant circuit, the inlet and outlet temperature and inlet and outlet pressure of the oil cooler of the cooling oil circuit, and the motor temperature.

7. The method for calculating the motor temperature field according to claim 1, characterized in that: After the three-dimensional heat flow simulation model outputs the temperature field of the motor, the method further includes: The temperature field of the motor is used to evaluate the risk point at which the temperature value of the motor exceeds a preset value.

8. A motor temperature field calculation device, characterized in that: include: An acquisition module, used to acquire the structural relationship of various components of the motor; Establishing a module, used to establish a one-dimensional temperature simulation model and a three-dimensional heat flow simulation model of the motor according to the structural relationship, and establishing a coupling model according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, wherein the coupling model is used for mutual mapping and transmission of parameters between the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model includes a finite element mesh model and a fluid-solid simulation model, the finite element mesh model is a model obtained by macro-gridding of each component of the motor, and the fluid-solid simulation model is a calculation model of the heat transfer coefficient of the cooling oil and solid components of the motor; the establishing of the coupling model according to the structural relationship, the one-dimensional temperature simulation model and the three-dimensional heat flow simulation model also includes: binding the mesh of the finite element mesh model and the boundary module of the one-dimensional temperature simulation model according to the structural relationship, and determining the mapping relationship between the heat transfer coefficient of the fluid-solid simulation model and the input condition of the boundary module according to the structural relationship; establishing a coupling model according to the bound mesh and boundary model and the mapping relationship; A generating module, used for identifying the one-dimensional temperature simulation model in the mutually mapped transferred parameters to calculate the temperature rise values ​​of the motor components and the heat transfer coefficient of the three-dimensional heat flow simulation model, and generating coupling parameters of the parameter transfer coupling model according to the temperature rise values ​​and the heat transfer coefficient; The output module is used to import the coupling parameters of the parameter transfer coupling model into the three-dimensional heat flow simulation model, and the three-dimensional heat flow simulation model outputs the temperature field of the motor.

9. A vehicle, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the motor temperature field calculation method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the motor temperature field calculation method described in any one of claims 1 to 7.

11. A computer program product having a computer program stored thereon, characterized in that: When the computer program is executed, it is used to implement the motor temperature field calculation method described in any one of claims 1-7.

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