An IGBT and board-level electro-thermal coupling method based on field-circuit coupling joint simulation

Abstract

The application discloses an IGBT and board-level electro-thermal coupling method based on field-circuit coupling joint simulation, which comprises the following steps: establishing an IGBT joint simulation circuit model based on an IGBT circuit model, a motor model and a vector control algorithm, calculating IGBT power consumption through joint simulation of the circuit model; establishing an IGBT temperature field finite element model based on the geometric size and internal characteristics of the IGBT, calculating IGBT junction temperature through finite element simulation; using a field-circuit coupling method, realizing electro-thermal coupling of the IGBT, and solving the IGBT junction temperature; based on an IGBT main control circuit and a power circuit model, establishing an IGBT main control circuit and power circuit board-level temperature field finite element model; using a field-circuit coupling method, realizing electro-thermal coupling of the IGBT main control circuit and the power circuit board-level, and solving the board-level temperature distribution. The heat transfer problem and the electrical problem of the IGBT module and the board-level can be solved jointly, compared with the prior art, the power consumption of the IGBT module can be accurately characterized, and the junction temperature and the board-level temperature of the IGBT module can be accurately calculated, thereby improving the reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power electronic device reliability, in particular to an IGBT and board-level electro-thermal coupling method based on field-circuit coupling joint simulation. BACKGROUND

[0002] Power electronic switching devices are increasingly widely used in the fields of smart grid, special power supply, high-speed rail traction, new energy power generation, electric vehicles, etc. Insulated gate bipolar transistor (IGBT) is a new generation of field-controlled power semiconductor device. The current IGBT not only has high switching frequency and high voltage resistance, but also has a conductive modulation effect. It plays a crucial role in the development of power electronic technology towards high frequency and high power density.

[0003] With the continuous development of process technology, the chip integration is getting higher and higher. According to the development trend of Moore's Law proposed by Moore in 1965, the number of transistors on a single chip can double every two years. At present, the size of the transistor has developed from the original micron level to the current nanometer level, and the number of transistors on a single chip has reached several billion. The rapid development of chip technology not only promotes modern technology, but also brings unprecedented challenges to its thermal management. Statistical analysis shows that when the temperature of electronic devices increases by 10℃, the reliability will decrease by 50%, and the failure caused by high temperature accounts for as high as 55% of all factors causing electronic device failure every year. A large amount of experimental data analysis shows that the life of power electronic switching devices is closely related to the junction temperature (chip temperature) of the device, so accurate junction temperature information is crucial for the reliability evaluation of power devices.

[0004] At present, there are three methods for electro-thermal coupling of multiple physical fields, namely circuit-thermal circuit method and finite element method. In the circuit-thermal circuit method, the circuit is established and calculated through physical and behavioral models, the loss value is obtained in the circuit level simulation software, the temperature distribution is obtained by building a thermal circuit network (Cauer or Foster), and the coupling is realized. Its shortcomings are obvious: one-way coupling, without considering the influence of temperature on device loss. At the same time, the thermal circuit method considers that heat is transferred in a single direction (from top to bottom), without considering lateral propagation, and the result is the average temperature after heat transfer of each layer. The finite element method is to calculate the model by finite element method, establish a 3D model, assign material properties (such as thermal conductivity, thermal expansion coefficient, etc.), apply thermal excitation to the chip (usually calculated by the electrical model), add reasonable boundary conditions and use discrete elements to solve the heat conduction equation to obtain the temperature distribution. This method brings greater computational load; in addition, the finite element method has higher requirements for users, and users need to reasonably apply boundary conditions, mesh and simplify the model to get the correct simulation results. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] In view of the above-mentioned problems, the present invention is proposed.

[0007] Therefore, the technical problem solved by this invention is that existing cloud service platform computing methods suffer from high power consumption, load factor penalties, and high costs, as well as the optimization problem of how to distribute task requests to various hosts to achieve load balancing.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation, comprising:

[0009] An IGBT co-simulation circuit model is established based on the IGBT circuit model, motor model, and vector control algorithm. The IGBT power consumption is calculated through co-simulation of the circuit model.

[0010] A finite element model of the IGBT temperature field is established based on the geometric dimensions and internal characteristics of the IGBT, and the junction temperature of the IGBT is calculated through finite element simulation.

[0011] Using the field-circuit coupling method, the electrothermal coupling of the IGBT is realized, and the junction temperature of the IGBT is solved.

[0012] Based on the IGBT main control circuit and power circuit model, a finite element model of the temperature field at the IGBT main control circuit and power circuit board level is established.

[0013] Using field-circuit coupling, electrothermal coupling between the IGBT main control circuit and the power circuit board level is achieved, and the temperature distribution at the IGBT board level is solved.

[0014] As a preferred embodiment of the IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, the method for establishing the IGBT co-simulation circuit model based on the IGBT circuit model, motor model, and vector control algorithm includes:

[0015] Based on the physical structure and electrical characteristics of IGBTs, an IGBT circuit component model is established.

[0016] Based on the IGBT circuit component model, a simulation model of the IGBT three-phase inverter circuit is established.

[0017] Based on the physical structure and parameters of the motor, a finite element simulation model of the motor is established;

[0018] Based on the characteristics of IGBT circuits and vector control algorithms, a simulation model of the vector control algorithm is established.

[0019] Based on the aforementioned IGBT three-phase inverter circuit simulation model, motor finite element simulation model, and vector control algorithm simulation model, an IGBT co-simulation circuit model is established.

[0020] As a preferred embodiment of the IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, wherein: the calculation of IGBT power consumption through circuit model co-simulation includes:

[0021] Based on the IGBT co-simulation circuit model, an IGBT conduction loss model and a switching loss model are established.

[0022] Based on the IGBT conduction loss model and switching loss model, the conduction loss and switching loss of IGBT are calculated.

[0023] Based on the calculated IGBT conduction loss and switching loss, the two are added together to calculate the IGBT loss.

[0024] As a preferred embodiment of the IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, wherein: the establishment of the IGBT temperature field finite element model based on the IGBT's geometric dimensions and internal features includes:

[0025] Based on the internal structure and geometric dimensions of IGBT, a three-dimensional structural model of IGBT is established.

[0026] Mesh the IGBT 3D structural model, set the boundary conditions and material properties of the IGBT 3D model, and establish the IGBT temperature field finite element model.

[0027] As a preferred embodiment of the IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, the method of using field-circuit coupling to realize the electrothermal coupling of IGBT includes: substituting the IGBT losses calculated by the co-simulation circuit model into the IGBT temperature field finite element model to calculate the IGBT junction temperature, and substituting the IGBT junction temperature calculated in the IGBT temperature field finite element model into the co-simulation circuit model to calculate the IGBT losses, thereby completing the field-circuit coupling of the circuit and the temperature field and realizing the electrothermal coupling of IGBT.

[0028] As a preferred embodiment of the IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, the IGBT junction temperature includes:

[0029] The calculation is repeated iteratively until the electrothermal coupling reaches equilibrium, thus accurately obtaining the IGBT junction temperature.

[0030] As a preferred embodiment of the IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, wherein: the IGBT main control circuit and power circuit model includes:

[0031] Based on the electrical characteristics of IGBTs, models of the IGBT main control circuit and power circuit are established to drive the motor.

[0032] Based on the IGBT main control circuit and power circuit model, a three-dimensional model of the IGBT main control circuit and power circuit is established.

[0033] As a preferred embodiment of the IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, wherein: the establishment of the finite element model of the temperature field at the IGBT main control circuit and power circuit board level includes:

[0034] Mesh the three-dimensional models of the IGBT main control circuit and power circuit, set boundary conditions and material properties, and establish the temperature field finite element model of the IGBT main control circuit and power circuit.

[0035] As a preferred embodiment of the IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, the method of using field-circuit coupling to realize the electrothermal coupling of the IGBT board level includes: substituting the IGBT losses calculated by the co-simulation circuit model into the finite element model of the temperature field of the IGBT main control circuit and power circuit to calculate the temperature distribution of the IGBT board level, and substituting the IGBT junction temperature calculated in the finite element model of the IGBT temperature field into the co-simulation circuit model to calculate the IGBT losses, thereby completing the field-circuit coupling of the circuit and the temperature field and realizing the electrothermal coupling of the IGBT board level.

[0036] As a preferred embodiment of the IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation described in this invention, the step of solving the IGBT plate-level temperature field distribution includes: iteratively calculating until the electrothermal coupling reaches equilibrium, thereby accurately obtaining the IGBT plate-level temperature field distribution.

[0037] The beneficial effects of this invention are as follows: The IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation provided by this invention can jointly solve the heat transfer and electrical problems of IGBT, accurately calculate the IGBT loss, and accurately calculate the junction temperature change and board-level temperature distribution of IGBT, thereby improving the accuracy of IGBT reliability assessment. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0039] Figure 1 A flowchart illustrating an IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation is provided for an embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of the IGBT co-simulation circuit model in an IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation provided in an embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the internal structure of the IGBT chip in an IGBT and board-level electrothermal coupling method based on field-circuit coupling co-simulation provided in an embodiment of the present invention. Detailed Implementation

[0042] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0043] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0044] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0045] This invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0046] Furthermore, in the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In addition, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0047] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] Example 1

[0049] Reference Figures 1-2 As an embodiment of the present invention, an IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation is provided, including:

[0050] S1: Establish an IGBT co-simulation circuit model based on the IGBT circuit model, motor model, and vector control algorithm, and calculate the IGBT power consumption through co-simulation of the circuit model.

[0051] Furthermore, the IGBT co-simulation circuit model is established by combining the IGBT circuit model, motor model, and vector control algorithm, including:

[0052] Based on the physical structure and electrical characteristics of IGBTs, an IGBT circuit component model is established.

[0053] Based on the IGBT circuit component model, a simulation model of the IGBT three-phase inverter circuit is established.

[0054] Based on the physical structure and parameters of the motor, a finite element simulation model of the motor is established;

[0055] Based on the characteristics of IGBT circuits and vector control algorithms, a simulation model of the vector control algorithm is established.

[0056] Based on the aforementioned IGBT three-phase inverter circuit simulation model, motor finite element simulation model, and vector control algorithm simulation model, an IGBT co-simulation circuit model is established.

[0057] It should be noted that the IGBT co-simulation circuit model consists of three parts: the IGBT circuit model, the motor model, and the vector control algorithm. Based on the IGBT's physical structure and electrical characteristics, an IGBT circuit component model is established in Simplier. Based on this IGBT circuit component model, an IGBT three-phase inverter circuit simulation model is established in Simplier. Based on the motor's physical structure and parameters, a motor finite element simulation model is established in Maxwell. Based on the IGBT circuit characteristics and the vector control algorithm, a vector control algorithm simulation model is established in Simulink. In Simplier, the Maxwell motor finite element simulation model and the Simulink vector control algorithm simulation model are imported into a modular form and connected to the IGBT circuit model. The Maxwell motor finite element simulation model serves as the load of the IGBT circuit model, and the Simulink vector control algorithm simulation model serves as the signal controlling the IGBT switching in the IGBT circuit model. These three components together form the IGBT co-simulation circuit model.

[0058] Furthermore, the calculation of IGBT power consumption through co-simulation of circuit models includes:

[0059] Based on the IGBT co-simulation circuit model, an IGBT conduction loss model and a switching loss model are established.

[0060] Based on the IGBT conduction loss model and switching loss model, the conduction loss and switching loss of IGBT are calculated.

[0061] Based on the calculated IGBT conduction loss and switching loss, the two are added together to calculate the IGBT loss.

[0062] It should be noted that the IGBT co-simulation circuit model establishes both the IGBT conduction loss model and the switching loss model. The specific conduction loss is shown in the following formula:

[0063]

[0064] Among them, u CE0 The zero-current collector-emitter voltage (r) represents the IGBT's on-state. C I represents the collector-emitter on-state resistance. cav I represents the average current of the IGBT. crms This represents the root mean square value of the IGBT current.

[0065] The specific formula for switching losses is as follows:

[0066] P swM =(E onM +E offM )·f sw

[0067] Among them, E onM E represents the IGBT's turn-on energy. offM f represents the IGBT's turn-off energy. sw This indicates the switching frequency of the IGBT.

[0068] Based on the turn-on loss and switching loss of IGBT, conduction loss model and switching loss model are established, and conduction loss and switching loss of IGBT are calculated.

[0069] S2: Based on the geometry and internal characteristics of the IGBT, a finite element model of the IGBT temperature field is established, and the junction temperature of the IGBT is calculated through finite element simulation.

[0070] Furthermore, a finite element model of the IGBT temperature field is established based on the IGBT's geometric dimensions and internal features, including:

[0071] Based on the internal structure and geometric dimensions of IGBT, a three-dimensional structural model of IGBT is established.

[0072] Mesh the IGBT 3D structural model, set the boundary conditions and material properties of the IGBT 3D model, and establish the IGBT temperature field finite element model.

[0073] Furthermore, the internal structure of the IGBT includes, as referenced Figure 3 The layers from top to bottom are silicon chip, upper solder layer, upper copper layer, ceramic dielectric layer, lower copper layer, lower solder layer, and substrate, to establish a three-dimensional internal structure model of IGBT.

[0074] S3: Using field-path coupling, achieve electrothermal coupling of the IGBT and solve for the IGBT junction temperature, including:

[0075] The IGBT losses calculated from the co-simulation circuit model are substituted into the IGBT temperature field finite element model to calculate the IGBT junction temperature, and the IGBT junction temperature calculated from the IGBT temperature field finite element model is substituted into the co-simulation circuit model to calculate the IGBT losses, thus completing the field-circuit coupling of the circuit and the temperature field and realizing the electrothermal coupling of the IGBT. The calculation is repeated iteratively until the electrothermal coupling reaches equilibrium, and the IGBT junction temperature is accurately obtained.

[0076] It should be noted that, in order to achieve electrothermal coupling between the IGBT co-simulation circuit model and the IGBT temperature field finite element model, field-circuit coupling is used. The junction temperature calculated by the IGBT temperature field finite element model is substituted into the IGBT co-simulation circuit model to recalculate the IGBT losses. Then, the recalculated IGBT losses are substituted into the established IGBT temperature field finite element model to calculate the junction temperature after the IGBT update iteration. It is then determined whether the difference between the updated IGBT junction temperature and the previous IGBT junction temperature meets the load electrothermal coupling balance standard. If it does not meet the standard, the iteration continues; if it does meet the standard, the accurate IGBT junction temperature is output.

[0077] It should be noted that the criteria for judging the electrothermal coupling balance are as follows: if the difference between the updated IGBT junction temperature and the previous IGBT junction temperature is less than 5% of the previous IGBT junction temperature, then the IGBT junction temperature electrothermal coupling balance is considered to be achieved, the iteration stops, and the accurate IGBT junction temperature can be derived.

[0078] S4: Based on the IGBT main control circuit and power circuit model, establish a finite element model of the temperature field at the IGBT main control circuit and power circuit board level, including:

[0079] Based on the electrical characteristics of IGBTs, models of the IGBT main control circuit and power circuit are established to drive the motor.

[0080] Based on the IGBT main control circuit and power circuit model, a three-dimensional model of the IGBT main control circuit and power circuit is established.

[0081] Mesh the three-dimensional models of the IGBT main control circuit and power circuit, set boundary conditions and material properties, and establish the temperature field finite element model of the IGBT main control circuit and power circuit.

[0082] S5: Using field-circuit coupling, achieve electrothermal coupling between the IGBT main control circuit and the power circuit board level, and solve for the board-level temperature distribution, including:

[0083] The calculated IGBT losses are substituted into the established finite element model of the IGBT main control circuit and power circuit board level temperature field to calculate the temperature distribution at the IGBT main control circuit and power circuit board level. To achieve electrothermal coupling between the IGBT co-simulation circuit model and the finite element model of the temperature field of the IGBT main control circuit and power circuit board level, field-circuit coupling is used. The temperature distribution of the IGBT main control circuit and power circuit board level calculated by the finite element model of the temperature field of the IGBT main control circuit and power circuit board level is substituted into the IGBT co-simulation circuit model to recalculate the IGBT losses. Then, the recalculated IGBT losses are substituted into the established finite element model of the temperature field of the IGBT main control circuit and power circuit board level to calculate the updated temperature distribution of the IGBT main control circuit and power circuit board level. It is then determined whether the updated board-level temperature distribution meets the electrothermal coupling balance standard compared with the previous board-level temperature distribution. If it does not meet the standard, the iteration continues; if it does meet the standard, the accurate temperature distribution of the IGBT main control circuit and power circuit board level is output.

[0084] It should be noted that the criteria for judging the electrothermal coupling balance are as follows: if the difference between the highest and lowest temperatures of the updated floor level and the highest and lowest temperatures of the previous board level is less than 5% of the highest and lowest temperatures of the previous board level, then the temperature field of the IGBT main control circuit and power circuit board level is considered to have achieved electrothermal coupling balance, the iteration stops, and the accurate temperature field distribution of the IGBT main control circuit and power circuit board level can be derived.

[0085] The present invention provides an IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation, which effectively improves the calculation accuracy and reduces the error when calculating IGBT losses, IGBT junction temperature, and IGBT plate-level temperature field, and effectively improves the reliability analysis of IGBT.

[0086] Example 2

[0087] One embodiment of the present invention provides a method for calculating IGBT chip losses and junction temperatures, and achieving electrothermal coupling through field-circuit coupling. The IGBT chip, specifically an Infineon chip, is simulated to accurately calculate its junction temperature. A co-simulation circuit model of the IGBT is constructed based on its chip characteristics and datasheet. An IGBT loss model is then established to calculate the IGBT losses. Through co-simulation, the calculated IGBT loss in the co-simulation circuit model is 18W.

[0088] Based on the internal structure of the IGBT, a three-dimensional model of the IGBT is established, and the internal structure of the chip is as follows: Figure 3As shown, from top to bottom, the layers are: silicon chip, upper solder layer, upper copper layer, ceramic dielectric layer, lower copper layer, lower solder layer, and substrate. In Icepak, the IGBT 3D model is meshed, boundary conditions are set, and material properties are configured for each layer to establish a finite element model of the IGBT temperature field.

[0089] Using field-circuit coupling, the calculated losses of the IGBT are substituted into the IGBT temperature field finite element model to calculate the IGBT junction temperature. Then, the junction temperature calculated from the IGBT temperature field finite element model is substituted into the IGBT co-simulation circuit model to recalculate the IGBT losses. Finally, the recalculated IGBT losses are substituted into the established IGBT temperature field finite element model to calculate the IGBT junction temperature after the update iteration. Then, the electrothermal coupling balance criterion is used to determine whether the IGBT junction temperature has reached electrothermal coupling balance. If balance has not been reached, iteration continues; if balance has been reached, iteration stops, and the accurate IGBT junction temperature is output.

[0090] This method uses field-circuit coupling to achieve electrothermal coupling. Compared with the traditional finite element method and circuit thermal method, the calculated IGBT junction temperature is more accurate, which effectively improves the analysis of IGBT reliability.

[0091] Example 3

[0092] This invention provides a method for calculating IGBT chip losses and the temperature field distribution of the IGBT board-level main control circuit and power circuit. Using the same Infineon IGBT chip, the steps for calculating the power consumption are the same as in Embodiment 2, both set at 18W. The main control circuit and power circuit are designed based on the characteristics of this IGBT chip and the purpose of driving the motor.

[0093] To ensure stable operation of the motor and normal functioning of the IGBT chip, the main control circuit is primarily divided into a main control chip minimum module, a power conversion module, a CAN communication module, and a current and voltage acquisition module; the power circuit is mainly divided into a drive module and a power module.

[0094] The main control chip's smallest module uses an STM32 microcontroller to perform related algorithm calculations, process feedback signals, and generate and send PWM signals through closed-loop control. The power conversion module generates different voltage levels from the input voltage to ensure power supply for each module in the circuit. The CAN communication module enables data communication between the host computer and the STM32. The voltage and current acquisition module collects the two-phase current and three-phase back electromotive force of the motor to calculate the motor's position and speed information and form a closed-loop control. The drive module receives PWM signals sent by the STM32 to control the switching transistors to turn on and off. The power module transfers energy to the motor and enables the motor to operate according to given conditions.

[0095] Based on the IGBT main control circuit and power circuit models, a finite element model of the temperature field at the IGBT main control circuit and power circuit board level is established. Using the field-circuit coupling method, the calculated losses of the IGBT and other chips under the same operating condition are substituted into the finite element model of the temperature field at the IGBT main control circuit and power circuit board level to calculate the temperature field distribution at the IGBT board level. Then, the IGBT junction temperature calculated by the finite element model of the temperature field at the IGBT main control circuit and power circuit board level is substituted into the IGBT co-simulation circuit model to recalculate the IGBT losses. The recalculated IGBT losses are then substituted into the established finite element model of the temperature field at the IGBT main control circuit and power circuit board level to calculate the junction temperature after the IGBT update iteration. Finally, the electrothermal coupling balance criterion is used to determine whether the temperature distribution at the IGBT board level has reached electrothermal coupling balance. If balance has not been reached, iteration continues; if balance has been reached, iteration stops, and the accurate temperature field distribution at the IGBT board level is output.

[0096] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for IGBT and plate-level electrothermal coupling based on field-circuit coupling co-simulation, characterized in that, include: An IGBT co-simulation circuit model is established based on the IGBT circuit model, motor model, and vector control algorithm. The IGBT power consumption is calculated through co-simulation of the circuit model. This includes: Based on the physical structure and electrical characteristics of IGBTs, an IGBT circuit component model is established. Based on the IGBT circuit component model, a simulation model of the IGBT three-phase inverter circuit is established. Based on the physical structure and parameters of the motor, a finite element simulation model of the motor is established; Based on the characteristics of IGBT circuits and vector control algorithms, a simulation model of the vector control algorithm is established. Based on the IGBT three-phase inverter circuit simulation model, motor finite element simulation model, and vector control algorithm simulation model, an IGBT joint simulation circuit model is established. Specifically, IGBT circuit component models and IGBT three-phase inverter circuit simulation models are established in Simplier, motor finite element simulation models are established in Maxwell, and vector control algorithm simulation models are established in Simulink. In Simplier, the Maxwell motor finite element simulation model and the Simulink vector control algorithm simulation model are imported and connected to the IGBT circuit model in a modular form. The Maxwell motor finite element simulation model serves as the load of the IGBT circuit model, and the Simulink vector control algorithm simulation model serves as the signal controlling the IGBT switch in the IGBT circuit model. A finite element model of the IGBT temperature field is established based on the geometric dimensions and internal characteristics of the IGBT, and the junction temperature of the IGBT is calculated through finite element simulation. Using the field-circuit coupling method, the electrothermal coupling of the IGBT is realized, and the junction temperature of the IGBT is solved. Based on the IGBT main control circuit and power circuit model, a finite element model of the temperature field at the IGBT main control circuit and power circuit board level is established. The IGBT main control circuit and power circuit model includes: Based on the electrical characteristics of IGBTs, models of the IGBT main control circuit and power circuit are established to drive the motor. Based on the IGBT main control circuit and power circuit model, a three-dimensional model of the IGBT main control circuit and power circuit is established. Using field-circuit coupling, electrothermal coupling between the IGBT main control circuit and the power circuit board level is achieved, and the temperature distribution at the IGBT board level is solved.

2. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 1, characterized in that: The calculation of IGBT power consumption through joint simulation using circuit models includes: Based on the IGBT co-simulation circuit model, an IGBT conduction loss model and a switching loss model are established. Based on the IGBT conduction loss model and switching loss model, the conduction loss and switching loss of IGBT are calculated. Based on the calculated IGBT conduction loss and switching loss, the two are added together to calculate the IGBT loss.

3. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 1, characterized in that: The establishment of the finite element model of the IGBT temperature field based on the IGBT's geometry and internal features includes: Based on the internal structure and geometric dimensions of IGBT, a three-dimensional structural model of IGBT is established. Mesh the IGBT 3D structural model, set the boundary conditions and material properties of the IGBT 3D model, and establish the IGBT temperature field finite element model.

4. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 1, characterized in that: The method of using field-circuit coupling to achieve electrothermal coupling of IGBTs includes: The IGBT losses calculated by the co-simulation circuit model are substituted into the IGBT temperature field finite element model to calculate the IGBT junction temperature, and the IGBT junction temperature calculated in the IGBT temperature field finite element model is substituted into the co-simulation circuit model to calculate the IGBT losses, thus completing the field-circuit coupling of the circuit and the temperature field and realizing the electrothermal coupling of the IGBT.

5. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 1 or 4, characterized in that: The IGBT junction temperature includes: The calculation is repeated iteratively until the electrothermal coupling reaches equilibrium, thus accurately obtaining the IGBT junction temperature.

6. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 5, characterized in that: The establishment of the finite element model of the temperature field at the IGBT main control circuit and power circuit board level includes: Mesh the three-dimensional models of the IGBT main control circuit and power circuit, set boundary conditions and material properties, and establish the temperature field finite element model of the IGBT main control circuit and power circuit.

7. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 1, characterized in that: The method of using field-path coupling to achieve electrothermal coupling at the IGBT board level includes: The IGBT losses calculated by the co-simulation circuit model are substituted into the finite element model of the temperature field of the IGBT main control circuit and power circuit to calculate the IGBT board-level temperature distribution. The IGBT junction temperature calculated in the IGBT temperature field finite element model is substituted into the co-simulation circuit model to calculate the IGBT losses, thus completing the field-circuit coupling of the circuit and the temperature field and realizing the electrothermal coupling of the IGBT board level.

8. The IGBT and plate-level electrothermal coupling method based on field-circuit coupling co-simulation as described in claim 7, characterized in that: The process of solving the IGBT board-level temperature distribution includes iterative calculations until the electrothermal coupling reaches equilibrium, thereby accurately obtaining the IGBT board-level temperature field distribution.

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