Junction temperature estimation method and device, motor controller, vehicle and product

Abstract

The invention discloses a junction temperature estimation method and device, a motor controller, a vehicle and a product, relates to the technical field of vehicle control, and discloses a junction temperature estimation method of a power module, comprising: determining a target loss calculation model according to a motor output frequency, the target loss calculation model comprising an instantaneous loss calculation model or an average loss calculation model; determining the loss of a power module in the motor controller based on the target loss calculation model and the motor operation parameters; the loss of the power module is input into a thermal circuit model for junction temperature estimation, the junction temperature of the power module is obtained, and the thermal circuit model is constructed according to thermal resistance parameters of the power module. By distinguishing different frequency bands and respectively applying the instantaneous loss calculation model and the average loss calculation model, the defect that the current power module junction temperature estimation scheme is poor in applicability under the locked-rotor working condition is effectively made up, and the method can be suitable for junction temperature estimation of the power module under different working condition scenes.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to junction temperature estimation methods, devices, motor controllers, vehicles, and products. Background Technology

[0002] Currently, commonly used online junction temperature estimation schemes for power modules consist of two parts: a loss calculation model and a thermal circuit model. The loss calculation model is based on the average loss calculation formula for a sinusoidal period under AC operating conditions, and uses real-time acquired motor operating parameters as input conditions to calculate the power module loss. During actual vehicle operation, the real-time calculation results of the loss calculation model are input into the thermal circuit model to obtain the corresponding junction temperature information of the power module, thus achieving online estimation of the power module junction temperature. However, the above-mentioned power module junction temperature estimation scheme is only applicable to AC operating conditions and not to other operating conditions (such as stalled rotor conditions, where the output current is DC), meaning that the current power module junction temperature estimation scheme has poor applicability. Summary of the Invention

[0003] The main purpose of this application is to provide a junction temperature estimation method, device, motor controller, vehicle, and product. It aims to achieve accurate loss calculation under different operating conditions by distinguishing different frequency bands and applying instantaneous loss calculation models and average loss calculation models respectively, while ensuring a low load rate. This effectively makes up for the shortcomings of current power module junction temperature estimation schemes in poor applicability under stall conditions and can be applied to the junction temperature estimation of power modules under different operating scenarios.

[0004] To achieve the above objectives, this application proposes a method for estimating the junction temperature of a power module, the method comprising:

[0005] The target loss calculation model is determined based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model;

[0006] Based on the target loss calculation model and motor operating parameters, the loss of the power module in the motor controller is determined;

[0007] The power module's losses are input into the thermal circuit model to estimate the junction temperature, thereby obtaining the junction temperature of the power module. The thermal circuit model is constructed based on the thermal resistance parameters of the power module.

[0008] In one embodiment, the step of determining the target loss calculation model based on the motor output frequency includes:

[0009] When the motor output frequency is less than the preset frequency, the target loss calculation model is determined to be the instantaneous loss calculation model;

[0010] Alternatively, when the motor output frequency is greater than or equal to the preset frequency, the target loss calculation model is determined to be the average loss calculation model.

[0011] In one embodiment, the step of determining the power module loss in the motor controller based on the target loss calculation model and motor operating parameters includes:

[0012] When the target loss calculation model is the instantaneous loss calculation model, the operating parameters of the first motor and the instantaneous loss coefficient of the power module are obtained;

[0013] The instantaneous loss of the power module is determined by calculating the loss based on the operating parameters of the first motor and the instantaneous loss coefficient.

[0014] In one embodiment, the step of determining the power module loss in the motor controller based on the target loss calculation model and motor operating parameters includes:

[0015] When the target loss calculation model is the average loss calculation model, the second motor operating parameters and the average loss coefficient of the power module are obtained.

[0016] The average loss of the power module is determined by calculating the loss based on the operating parameters of the second motor and the average loss coefficient.

[0017] In one embodiment, the step of inputting the power module's losses into a thermal circuit model to estimate the junction temperature and obtain the power module's junction temperature includes:

[0018] The power module loss is input into the thermal circuit model to obtain the temperature difference of the power module;

[0019] The junction temperature of the power module is determined based on the sampling temperature of the power module and the temperature difference.

[0020] In one embodiment, the method further includes:

[0021] The temperature rise of each chip in the power module when it generates heat and the loss of each chip are obtained.

[0022] The self-thermal resistance of each chip is determined based on the temperature rise and corresponding losses when each chip generates its own heat.

[0023] The thermal conduction temperature rise of the current chip due to the heat generated by other chips, as well as the losses of the other chips, are obtained.

[0024] Based on the heat conduction temperature rise and the losses of the other chips, determine the mutual thermal resistance of the other chips relative to the current chip;

[0025] The thermal circuit model is constructed based on the self-thermal resistance and mutual thermal resistance of each chip.

[0026] In one embodiment, the losses include the self-loss and mutual loss of each chip, and the thermal resistance parameters include the self-thermal resistance and mutual thermal resistance of each chip. The step of inputting the losses of the power module into the thermal circuit model to obtain the temperature difference of the power module includes:

[0027] The first temperature difference of each chip is obtained by multiplying the self-loss and self-thermal resistance of each chip, and the second temperature difference of each chip is obtained by multiplying the mutual loss and mutual thermal resistance of each chip.

[0028] The temperature difference of each chip is obtained by summing the first and second temperature differences of each chip.

[0029] The temperature difference of the power module is determined by summing the temperature differences of each chip.

[0030] Furthermore, to achieve the above objectives, this application also proposes a junction temperature estimation device for a power module, the junction temperature estimation device for the power module comprising:

[0031] The target loss calculation model determination module is used to determine the target loss calculation model based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model.

[0032] The loss determination module is used to determine the loss of the power module in the motor controller based on the target loss calculation model and the motor operating parameters.

[0033] The junction temperature determination module is used to input the power module's losses into the thermal circuit model to estimate the junction temperature and obtain the junction temperature of the power module.

[0034] In addition, to achieve the above objectives, this application also proposes a motor controller, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the junction temperature estimation method for the power module as described above.

[0035] In addition, to achieve the above objectives, this application also proposes a vehicle including the motor controller described above.

[0036] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the junction temperature estimation method for the power module as described above.

[0037] Compared to related technologies where power module junction temperature estimation schemes are only applicable to the average loss calculation of a sinusoidal period under AC operating conditions, resulting in poor applicability, this application distinguishes between different frequency bands and applies instantaneous loss calculation models and average loss calculation models respectively. This enables accurate loss calculation under different operating conditions while ensuring a low load rate, effectively overcoming the shortcomings of current power module junction temperature estimation schemes in stalled operating conditions. It can be applied to the junction temperature estimation of power modules under different operating scenarios. Attached Figure Description

[0038] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0039] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart illustrating an embodiment of the junction temperature estimation method for the power module of this application.

[0041] Figure 2 This is a flowchart illustrating another embodiment of the junction temperature estimation method for the power module of this application.

[0042] Figure 3 This is a schematic diagram of the packaging of the power module of this application;

[0043] Figure 4 This is a schematic diagram of the junction temperature estimation device for the power module in an embodiment of this application.

[0044] Figure 5 This is a schematic diagram of the structure of the motor controller in the embodiment of this application.

[0045] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0047] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0048] The main solution of this application embodiment is: determining a target loss calculation model based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model; determining the loss of the power module in the motor controller based on the target loss calculation model and the motor operating parameters; inputting the loss of the power module into the thermal circuit model for junction temperature estimation to obtain the junction temperature of the power module, wherein the thermal circuit model is constructed based on the thermal resistance parameters of the power module.

[0049] In this embodiment, for ease of description, the motor controller will be used as the execution subject in the following description.

[0050] Because existing power module junction temperature estimation schemes are only applicable to AC operating conditions and not to other operating conditions (such as locked rotor operating conditions, where the output current is DC), the applicability of current power module junction temperature estimation schemes is poor.

[0051] This application provides a solution that addresses the limitation of existing power module junction temperature estimation schemes, which are only applicable to the average loss calculation of a sinusoidal period under AC operating conditions and suffer from poor applicability. By differentiating between different frequency bands and applying instantaneous loss calculation models and average loss calculation models respectively, this application achieves accurate loss calculation under different operating conditions while ensuring a low load rate. This effectively overcomes the shortcomings of current power module junction temperature estimation schemes in poor applicability under stall conditions and enables the estimation of power module junction temperatures under various operating scenarios.

[0052] Furthermore, in related technologies, the thermal circuit model is constructed offline by obtaining the thermal resistance parameters between different nodes of the module through thermal simulation of boundary conditions. Currently, the chip layout of common power modules is as follows: Figure 3 As shown, a module contains six bridge arms, each with multiple power semiconductor chips. According to thermal coupling theory, when multiple chips generate heat, the temperature rise of a chip equals its self-heating temperature rise plus the mutual temperature rise caused by heat conduction from other chips. Therefore, the thermal coupling state between the chips changes with the loss distribution. However, existing thermal circuit models extract thermal resistance parameters based on thermal simulation results under boundary conditions, which are only applicable to conditions with loss distributions not significantly different from those boundary conditions. However, vehicle operating conditions are complex and varied. Under different modulation ratios and power factors, the loss distribution of IGBT and diode chips changes. Therefore, thermal resistance parameters extracted from only one boundary condition cannot cover all motor operating conditions.

[0053] To address the aforementioned issues, this application decouples the thermal coupling between different bridge arm chips in the power module, constructs a decoupled thermal resistance model, and improves the applicability, accuracy, and robustness of the junction temperature estimation scheme, adapting to various complex operating conditions of vehicles.

[0054] In one application scenario, vehicle operating conditions are complex and varied. Under specific conditions (such as climbing hills or acceleration), the power module in the motor controller will experience drastic temperature changes, which can easily lead to overheating failure. Therefore, it is necessary to incorporate a suitable junction temperature estimation strategy into the design to monitor the junction temperature of the power module in real time, ensuring the stable and reliable operation of the motor controller. For this application scenario, a thermal circuit model can be constructed and integrated into the microcontroller unit of the motor controller. During actual vehicle operation, the real-time calculation results of the loss model can be input into the thermal circuit model to obtain the corresponding junction temperature information, enabling online estimation of the junction temperature of the power module.

[0055] It should be noted that the junction temperature estimation scheme for the power module in this application is not limited to vehicle use scenarios, but can also be applied to other scenarios, such as CNC machine tool control scenarios, elevator control scenarios, or other scenarios where power modules are installed and junction temperature estimation of the power modules is required. This application takes the vehicle use scenario as an example.

[0056] It should be noted that the vehicles mentioned above can be either electric vehicles or gasoline-powered vehicles.

[0057] It should be noted that the power module in this application is a power semiconductor device. Power semiconductor devices are key components used for controlling and regulating power, and are used in high-power and high-frequency applications. The main power semiconductor devices include:

[0058] 1. Power transistor:

[0059] BJT (Bipolar Junction Transistor): Used for medium to high power switching and amplification.

[0060] FET (Field-Effect Transistor): Includes metal-oxide-semiconductor field-effect transistors (MOSFETs) and insulated-gate bipolar transistors (IGBTs), used in high-power switching applications.

[0061] 2. Rectifier and diode:

[0062] Rectifier diodes: used to convert alternating current (AC) to direct current (DC), such as in bridge rectifiers.

[0063] Fast recovery diodes: used in power supply applications requiring high-speed switching and low reverse recovery time.

[0064] Schottky diodes: featuring low turn-on voltage and fast switching speed, suitable for high-frequency power supply applications.

[0065] 3. IGB (Insulated Gate Bipolar Transistor):

[0066] Combining the high input impedance of MOSFETs and the low on-state voltage drop of BJTs, it is suitable for high-voltage and high-power applications, such as electric vehicle control and frequency converters.

[0067] 4. Thyristors: including bidirectional thyristors (Triac) and unidirectional thyristors (SCR), used for high-power AC switching and control.

[0068] 6. Power Module: This module integrates multiple power semiconductor devices (such as IGBTs and diodes) along with their drive circuits and protection functions. It simplifies design and improves system integration and is commonly used in applications such as motor drives, frequency converters, and UPS.

[0069] 7. Power Integrated Circuits: These integrate various power control and management functions, such as switching power supply controllers and power management units, to provide stable and efficient power output.

[0070] This application takes the aforementioned power module as an example. The power module can be a six-arm bridge, a half-arm bridge (two-arm bridge), an H-bridge (four-arm bridge), or even a multi-in-one (eight-arm bridge, twelve-arm bridge, etc.). This application takes a six-arm bridge as an example.

[0071] A six-axle arm typically refers to a specific electric vehicle drive system topology, particularly when using a multiphase (usually three-phase) motor. In vehicles, multiple power semiconductor devices are typically used to drive the motor to provide the required power and efficiency. A six-axle arm system generally includes the following key components:

[0072] 1. Motor: Usually a permanent magnet synchronous motor or an induction motor, used to provide power for the vehicle.

[0073] 2. Power Semiconductor Devices: Each bridge arm (typically six bridge arms) uses an independent power semiconductor device to control the motor current. These devices include power transistors (such as IGBTs or MOSFETs) and rectifier diodes, used to form different bridge circuits.

[0074] 3. Bridge Circuit: The six-bridge system consists of six bridge circuits. Each bridge consists of switching devices (usually IGBTs and anti-parallel diodes, or MOSFETs) and anti-parallel diodes. These bridge circuits are used to control the phase current and voltage of the motor to achieve forward and reverse operation and braking functions.

[0075] 4. Control Circuits: These include gate drive circuits for driving power devices and current feedback control systems. These control circuits are responsible for ensuring the stability, efficiency, and safety of the motor during operation.

[0076] Based on this, embodiments of this application provide a method for estimating the junction temperature of a power module, referring to... Figure 1 , Figure 1 This is a flowchart illustrating an embodiment of the junction temperature estimation method for the power module of this application.

[0077] In this embodiment, the junction temperature estimation method for the power module includes steps S10 to S30:

[0078] Step S10: Determine the target loss calculation model based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model.

[0079] It's important to note that motor output frequency refers to the output frequency of the motor rotor, typically expressed as the frequency or speed at which the rotor rotates, usually measured in Hertz (Hz). This frequency directly affects the motor's operating speed and output power, and is a crucial indicator for evaluating its operating status and performance. Motor output frequency can be acquired in real-time or at set intervals. For example, during vehicle operation, the motor output frequency can be acquired in real-time or at set intervals to monitor the vehicle's operating conditions.

[0080] It should be noted that obtaining the motor rotor output frequency typically depends on the motor type and application environment. The motor rotor output frequency can be obtained through the following methods:

[0081] For example, the output frequency of a motor rotor can be obtained through a speed sensor. Hall effect sensors detect changes in the magnetic field on the motor rotor to measure its rotational speed; these are commonly used in DC motors and some AC motors. Alternatively, photoelectric encoders use photoelectric sensors and a rotating encoder disk to detect the position and speed of the motor rotor, providing very accurate speed measurements suitable for applications requiring high-precision control. For example, motor controllers often have built-in speed detection capabilities, using internal algorithms and feedback loops to measure the motor's speed and output frequency, suitable for applications requiring real-time control and adjustment. For example, the output frequency of a motor rotor can be indirectly measured using a vibration sensor. The rotation of the motor rotor generates vibration signals at specific frequencies, which the vibration sensor can detect and convert into speed data. For example, for AC motors, the AC frequency on the power line can be measured by connecting a frequency meter or oscilloscope; this frequency is usually associated with the motor rotor's output frequency.

[0082] In related technologies, only the average loss calculation model is built into the motor controller, which cannot calculate the power module loss under stall conditions. This is detrimental to the motor controller's control of the motor under stall conditions, thus affecting vehicle driving safety. To address this deficiency, this application integrates both the average loss calculation model and the instantaneous loss calculation model into the motor controller, which can meet the power module loss calculation needs under different operating conditions.

[0083] It's important to note that the motor output frequency varies under different vehicle operating conditions, requiring different loss calculation models to meet the demands of each. For example, during actual vehicle operation, once a rotational speed is generated, the output current becomes a sine wave, indicating AC operation. In this case, an average loss calculation model is needed to calculate the periodic average loss of the power module. However, besides AC operation, vehicles may experience stalled conditions when climbing hills or crossing curbs, in which case the output current becomes DC. In this scenario, an instantaneous loss calculation model is required to calculate the instantaneous loss of the power module. In other words, the instantaneous loss calculation model is suitable for calculating power module losses under stalled conditions (DC output current), while the average loss calculation model is suitable for AC operation. The loss model formulas for the instantaneous and average loss calculation models differ, as do the types and number of input motor operating parameters, to meet the power module loss calculation requirements under different operating conditions. A significant difference is that the instantaneous loss model requires instantaneous output current sampling data i. o (t), the average loss model needs to obtain the effective value of the output current I. orm .

[0084] In one feasible implementation, the current operating condition of the vehicle can be determined based on the motor output power, and then a target loss calculation model can be determined based on the current operating condition of the vehicle. Specifically, a correspondence between different motor output powers, vehicle operating conditions, and the target loss calculation model can be pre-set. Based on this correspondence and the motor output power, the target loss calculation model is determined, thereby realizing the determination of the loss calculation model under different vehicle operating condition scenarios.

[0085] It should be noted that the preset frequency can be set to a range of 5Hz to 10Hz. The preset frequency is also called the setting switching frequency.

[0086] In another feasible implementation, when the motor output frequency is less than a preset frequency, the target loss calculation model is determined to be the instantaneous loss calculation model; when the motor output frequency is greater than or equal to the preset frequency, the target loss calculation model is determined to be the average loss calculation model. The preset frequency can be set to a range of 5Hz to 10Hz. After the vehicle starts, the selection of either the instantaneous or average loss calculation model is determined by comparing the motor output frequency with the preset frequency. The main difference between the two models lies in the loss calculation formula and input parameters. Due to the limitation of the MCU load rate, the maximum calculation frequency of the instantaneous loss calculation model is generally less than one-tenth of the carrier frequency. To ensure that the calculation distortion does not affect the accuracy, the transient loss calculation model is usually applied to operating conditions below the set switching frequency.

[0087] Step S20: Based on the target loss calculation model and motor operating parameters, determine the loss of the power module in the motor controller;

[0088] It should be noted that the motor operating parameters differ under different operating conditions. For example, under stall conditions, the motor operating parameters are the first set of motor operating parameters, which specifically include, but are not limited to, the DC bus voltage, the sampled instantaneous output current, the corresponding IGBT gate duty cycle, and the switching frequency. Under AC conditions, the motor operating parameters are the second set of motor operating parameters, which specifically include, but are not limited to, the motor controller bus voltage, the effective value of the output current, the motor rotor output frequency, the carrier frequency data, the duty cycle, and the power factor.

[0089] It should be noted that the power module's losses consist of different parts, including but not limited to switching device losses, drive circuit losses, heat dissipation and cooling losses, and other losses. The following will provide a detailed description of each loss component:

[0090] (1) Switching device losses include conduction losses and switching losses. In power modules, switching devices (such as MOSFETs and IGBTs) have a certain resistance when in the on-state, resulting in heat loss as current flows. Furthermore, energy loss occurs during the switching process due to rapid current changes. This portion of switching losses is closely related to the switching frequency, current magnitude, and characteristics of the switching device.

[0091] (2) Drive circuit losses include drive current consumption and drive circuit efficiency. The drive circuits in the motor controller need to provide sufficient drive current to the switching devices, and these drive circuits themselves also consume power. Furthermore, drive circuit efficiency directly affects the overall system power consumption and heat generation.

[0092] (3) Heat dissipation and cooling losses include thermal conductivity and radiator losses, as well as cooling fan power consumption. Heat sinks and thermally conductive materials are typically used to effectively cool power modules and reduce temperature. These additional devices and methods may introduce some additional power consumption. Furthermore, in high-power motor control systems, cooling fans may be used to enhance heat dissipation, but they also consume electrical energy.

[0093] (4) Other losses include inductance and capacitance losses. Inductors and capacitors in the power module may incur additional losses due to current variations and loss mechanisms. Furthermore, the resistance of cables and connectors, as well as the connection method, may also introduce some power consumption.

[0094] In this embodiment, after determining the target loss calculation model, the currently collected motor operating parameters are input into the corresponding target loss calculation model for loss calculation, thereby obtaining the loss calculation of the power module adapted to the current vehicle operating conditions.

[0095] Step S30: Input the power module loss into the thermal circuit model to estimate the junction temperature and obtain the junction temperature of the power module. The thermal circuit model is constructed based on the thermal resistance parameters of the power module.

[0096] It should be noted that junction temperature refers to the actual operating temperature of internal components (such as MOSFETs, IGBTs, etc.) of the power module. It can be calculated by finite element analysis software or estimated based on empirical formulas and experimental data. This application can integrate the thermal model into the microcontroller program of the motor controller to achieve online junction temperature estimation.

[0097] It should be noted that the thermal circuit model is a three-dimensional thermal simulation model based on the heat dissipation packaging and layered materials of the power module. Thermal simulation is used to obtain the thermal resistance parameters between different nodes of the power module. A decoupling thermal resistance matrix is ​​constructed based on these parameters, and then the thermal circuit model is built from this matrix and integrated into the microcontroller program of the motor controller. The elements (i.e., thermal resistance parameters) within the decoupling thermal resistance matrix mainly include the self-thermal resistance Z, which characterizes the effect of self-temperature rise. th自 Mutual thermal resistance Z, which characterizes the mutual temperature rise effect. th互 After calculating the power module's losses using the loss model, these losses are input into the thermal circuit model and, together with the thermal resistance parameters in the decoupled thermal resistance matrix, are used to calculate the power module's junction temperature.

[0098] In this embodiment, during actual vehicle operation, the power module loss calculated in real time by the target loss model is input into the thermal circuit model to obtain the corresponding junction temperature information, thereby achieving online estimation of the junction temperature.

[0099] This embodiment provides a method for estimating the junction temperature of a power module. Compared with related technologies, which only apply to the average loss calculation of a sinusoidal period under AC operating conditions and have poor applicability, this application distinguishes different frequency bands and applies instantaneous loss calculation models and average loss calculation models respectively. Under the premise of ensuring a low load rate, it achieves accurate loss calculation under different operating conditions, effectively making up for the shortcomings of the current power module junction temperature estimation scheme in poor applicability under stall conditions. It can be applied to the junction temperature estimation of power modules under different operating conditions.

[0100] Furthermore, in one embodiment, step S20 includes steps A21 to A22:

[0101] Step A21: When the target loss calculation model is the instantaneous loss calculation model, obtain the first motor operating parameters and the instantaneous loss coefficient of the power module.

[0102] Step A22: Calculate the instantaneous loss of the power module based on the operating parameters of the first motor and the instantaneous loss coefficient.

[0103] In this embodiment, the operating parameters of the first motor are input into the instantaneous loss calculation model, and the instantaneous loss coefficient is used for calculation to obtain the instantaneous loss of the power module. It should be noted that the instantaneous loss of the power module includes self-instantaneous loss and mutual instantaneous loss. Both self-instantaneous loss and mutual instantaneous loss include IGBT losses and the losses of the diodes parasitic on the IGBT. IGBT losses further include IGBT conduction losses and IGBT switching losses, and diode losses further include diode conduction losses and diode switching losses. Therefore, the instantaneous loss of the power module is the sum of the losses described above.

[0104] Furthermore, in one embodiment, the operating parameters of the first motor include, but are not limited to, the DC bus voltage, the instantaneous current flowing through the IGBT, the instantaneous current flowing through the IGBT parasitic diode, the IGBT duty cycle, the switching frequency, the bus voltage corresponding to the IGBT turn-on, the bus voltage corresponding to the IGBT turn-off, and the bus voltage corresponding to the IGBT parasitic diode turn-off. The instantaneous loss factor includes, but is not limited to, the IGBT voltage drop, the diode voltage drop, the energy required to turn on the IGBT, the energy required to turn off the IGBT, and the reverse recovery energy of the IGBT parasitic diode.

[0105] In one feasible implementation, the instantaneous loss of the power module can be calculated based on the DC bus voltage, the instantaneous current flowing through the IGBT, the instantaneous current flowing through the IGBT parasitic diode, the IGBT duty cycle, the switching frequency, the bus voltage corresponding to the IGBT turn-on and the bus voltage corresponding to the IGBT turn-off, the bus voltage corresponding to the IGBT parasitic diode turn-off, the IGBT voltage drop, the diode voltage drop, the energy required for the IGBT to turn on, the energy required for the IGBT to turn off, and the reverse recovery energy of the IGBT parasitic diode.

[0106] Specifically, the instantaneous conduction loss of the IGBT is calculated based on the instantaneous current flowing through the IGBT, the IGBT's voltage drop, and the IGBT's duty cycle. The instantaneous switching loss of the IGBT is calculated based on the switching frequency, DC bus voltage, instantaneous current flowing through the IGBT, the energy required for the IGBT to turn on, the energy required for the IGBT to turn off, the bus voltage corresponding to the IGBT's turn-on, and the bus voltage corresponding to the IGBT's turn-off. The instantaneous switching loss is calculated based on the voltage drop of the IGBT's parasitic diode, the instantaneous current flowing through the IGBT's parasitic diode, and the IGBT's duty cycle. The instantaneous conduction loss of the IGBT parasitic diode is calculated. The instantaneous switching loss of the IGBT parasitic diode is calculated based on the switching frequency, DC bus voltage, the bus voltage corresponding to the IGBT parasitic diode turn-off, and the reverse recovery energy of the IGBT parasitic diode. Instantaneous line loss is also calculated. Finally, the instantaneous conduction loss of each IGBT, the instantaneous switching loss of each IGBT, the instantaneous conduction loss of each IGBT parasitic diode, the instantaneous switching loss of each IGBT parasitic diode, and the instantaneous line loss are added together to obtain the instantaneous loss of the power module.

[0107] For example, the instantaneous losses of each IGBT and its parasitic diodes in the power module are calculated using formula (1). Formula (1) includes five sub-formulas, which are referred to as the first to the fifth sub-formulas below:

[0108]

[0109] The first sub-formula is used to calculate the instantaneous conduction loss of the IGBT, V. ce (i o ) represents the voltage drop across the IGBT, i o D represents the instantaneous current flowing through the IGBT. on This represents the IGBT's duty cycle. The second sub-formula is used to calculate the IGBT's instantaneous switching losses, f. sw U represents the switching frequency, and U represents the DC bus voltage. norm E represents the bus voltage corresponding to when the IGBT is turned on and the bus voltage corresponding to when the IGBT is turned off. on(i o E represents the energy required to turn on the IGBT. off (i o The value V represents the energy required to turn off the IGBT. The third sub-formula is used to calculate the instantaneous conduction loss of the parasitic diode of the IGBT. f (i o () represents the voltage drop across the parasitic diode of the IGBT, i o This represents the instantaneous current flowing through the parasitic diode of the IGBT, (1-D) on The ) represents the duty cycle of the IGBT parasitic diode. The fourth sub-formula is used to calculate the instantaneous switching loss of the IGBT parasitic diode, i o U represents the instantaneous current flowing through the parasitic diode of the IGBT, and U represents the DC bus voltage. norm E represents the bus voltage corresponding to the IGBT parasitic diode being turned off. rec (i o This represents the reverse recovery energy of the IGBT parasitic diode. The fifth sub-formula is used to calculate the instantaneous line loss, R. ccee Indicates line resistance.

[0110] In this embodiment, by setting an instantaneous loss calculation model, the instantaneous loss of the power module can be calculated under DC conditions using the operating parameters of the first motor and the instantaneous loss coefficient, thereby achieving accurate calculation of the instantaneous loss of the power module under DC conditions.

[0111] Furthermore, in one embodiment, step S20 includes steps B21 to B22:

[0112] Step B21: When the target loss calculation model is the average loss calculation model, obtain the second motor operating parameters and the average loss coefficient of the power module.

[0113] Step B22: Calculate the average loss of the power module based on the operating parameters of the second motor and the average loss coefficient.

[0114] In this embodiment, the operating parameters of the second motor are input into the average loss calculation model, and the average loss coefficient is used for calculation to obtain the average loss of the power module. It should be noted that the average loss of the power module includes self-average loss and mutual-average loss. Both self-average loss and mutual-average loss include IGBT losses and the losses of the IGBT's parasitic diodes. IGBT losses further include IGBT conduction losses and IGBT switching losses, and diode losses further include diode conduction losses and diode switching losses. Therefore, the average loss of the power module is the sum of the losses described above.

[0115] It should be noted that the average loss coefficient can be obtained through experimental calibration.

[0116] Furthermore, in one embodiment, the operating parameters of the second motor include, but are not limited to, the effective value of the current flowing through the IGBT, the effective value of the current flowing through the IGBT parasitic diode, the IGBT modulation ratio, the power factor, the effective value of the current flowing through the IGBT parasitic diode, the DC bus voltage, the bus voltage corresponding to the IGBT turn-on and the bus voltage corresponding to the IGBT turn-off, the bus voltage corresponding to the IGBT parasitic diode turn-off, the IGBT parasitic diode modulation ratio, and the switching frequency. The average loss coefficient includes the first to fourth average loss coefficients when the IGBT is on, the fifth and sixth average loss coefficients when the IGBT is on, the seventh to tenth average loss coefficients when the diode is on, and the eleventh and twelfth average loss coefficients when the diode is on.

[0117] In one feasible implementation, the average loss of the power module can be calculated based on the effective value of the current flowing through the IGBT, the effective value of the current flowing through the IGBT parasitic diode, the IGBT modulation ratio, the power factor, the effective value of the current flowing through the IGBT parasitic diode, the DC bus voltage, the bus voltage corresponding to the IGBT turn-on and the bus voltage corresponding to the IGBT turn-off, the bus voltage corresponding to the IGBT parasitic diode turn-off, the IGBT parasitic diode modulation ratio, the switching frequency, and in combination with the first to twelfth average loss coefficients.

[0118] Specifically, the average conduction loss of the IGBT is calculated based on the RMS value of the current flowing through the IGBT, the IGBT modulation ratio, the power factor, the first average loss coefficient, the second average loss coefficient, the third average loss coefficient, and the fourth average loss coefficient. The average switching loss of the IGBT is calculated based on the DC bus voltage, the bus voltage corresponding to the IGBT turn-on and the bus voltage corresponding to the IGBT turn-off, the switching frequency, the RMS value of the current flowing through the IGBT, the fifth average loss coefficient, and the sixth average loss coefficient. The average conduction loss of the diode is calculated based on the RMS value of the current flowing through the diode, the diode modulation ratio, the power factor, the seventh average loss coefficient, the eighth average loss coefficient, the ninth average loss coefficient, and the tenth average loss coefficient. The average switching loss of the diode is calculated based on the DC bus voltage, the bus voltage corresponding to the IGBT parasitic diode turn-off, the switching frequency, the RMS value of the current flowing through the diode, the eleventh average loss coefficient, and the twelfth average loss coefficient. The average line loss is also calculated. Finally, the average loss of the power module is obtained by summing the average conduction loss of each IGBT, the average switching loss of each IGBT, the average conduction loss of each diode, the average switching loss of each diode, and the average line loss.

[0119] For example, the average loss of each IGBT and its parasitic diode in the power module is calculated using formula (2). Formula (2) includes five sub-formulas, which are referred to as the first to the fifth sub-formulas below:

[0120]

[0121] The first sub-formula is used to calculate the average conduction loss of the IGBT, K. conQ1 To K conQ4 These represent the first to fourth average loss coefficients, respectively. orm The first formula represents the effective value of the current flowing through the IGBT, where M represents the IGBT modulation ratio and PF represents the power factor. The second formula is used to calculate the average switching loss of the IGBT, f. sw U represents the switching frequency, and U represents the DC bus voltage. norm K represents the bus voltage corresponding to when the IGBT is turned on and the bus voltage corresponding to when the IGBT is turned off. swQ1 and K swQ2 These represent the fifth and sixth average loss coefficients, respectively. The third sub-formula is used to calculate the average conduction loss of the IGBT parasitic diode, K. conD1 To K conD3 They represent the seventh to tenth average loss coefficients, respectively. orm The formula represents the effective value of the current flowing through the diode, M represents the diode modulation ratio, and PF represents the power factor. The fourth formula is used to calculate the average switching loss of the parasitic diode of the IGBT, K. swD1 and K swD2 I represents the eleventh and twelfth average loss coefficients, respectively. orm U represents the effective value of the current flowing through the parasitic diode of the IGBT, and U represents the DC bus voltage. norm This represents the bus voltage when the IGBT parasitic diode is turned off. The fifth formula is used to calculate the average line loss, R. ccee Indicates line resistance.

[0122] In this embodiment, by setting an average loss calculation model, the average loss of the power module can be calculated under AC operating conditions using the operating parameters of the second motor and the average loss coefficient, thus achieving accurate calculation of the average loss of the power module under AC operating conditions.

[0123] Based on the above embodiments of this application, in one embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 2 Step S30 includes steps S31 to S32:

[0124] Step S31: Input the power module loss into the thermal circuit model to obtain the temperature difference of the power module;

[0125] It should be noted that the thermal circuit model is a three-dimensional thermal simulation model built based on the heat dissipation packaging and layered materials of the power module. Thermal simulation is used to obtain the thermal resistance parameters between different nodes of the power module. A decoupling thermal resistance matrix is ​​constructed based on these parameters, and then the thermal circuit model is built from the decoupling thermal resistance matrix and integrated into the microcontroller program of the motor controller. The elements (i.e., thermal resistance parameters) within the decoupling thermal resistance matrix mainly include the self-thermal resistance Z, which characterizes the effect of self-temperature rise. th自 Mutual thermal resistance Z, which characterizes the mutual temperature rise effect. th互 After calculating the power module's losses using the loss model, these losses are input into the thermal circuit model and, together with the thermal resistance parameters in the decoupled thermal resistance matrix, the temperature difference of the power module is calculated.

[0126] Taking a power module with six bridge arms as an example, each bridge arm contains multiple power semiconductor chips. Therefore, the power module's losses include the sum of the losses of each individual chip, and the power module's temperature difference includes the sum of the temperature differences of each individual chip.

[0127] Each chip's losses include both self-loss and mutual loss; therefore, the power module's losses include the sum of each chip's self-loss and mutual loss. Similarly, the decoupling thermal resistance matrix in the thermal circuit model essentially includes the thermal resistance parameters of each chip, and each chip's thermal resistance parameters include both self-thermal resistance and mutual thermal resistance. Therefore, the power module's temperature difference includes the sum of each chip's self-thermal resistance and mutual thermal resistance.

[0128] In one feasible implementation, the temperature rise of each chip in the power module during self-heating and the losses of each chip can be obtained; based on the temperature rise and corresponding losses of each chip during self-heating, the self-thermal resistance of each chip can be determined; the thermal conduction temperature rise of other chips on the current chip and the losses of the other chips can be obtained; based on the thermal conduction temperature rise and the losses of the other chips, the mutual thermal resistance of the other chips relative to the current chip can be determined; and the thermal circuit model can be constructed based on the self-thermal resistance and mutual thermal resistance of each chip. Specifically, constructing the thermal circuit model based on the self-thermal resistance and mutual thermal resistance of each chip includes: constructing a decoupled thermal resistance matrix based on the self-thermal resistance and mutual thermal resistance of each chip, and then generating the thermal circuit model based on the decoupled thermal resistance matrix.

[0129] It's important to clarify that self-dissipation refers to the heat generated by the chip itself due to internal resistance or other mechanisms. When current flows through the chip, resistance generates heat, causing the chip temperature to rise. If this heat cannot be effectively dissipated, the chip temperature will continue to rise, potentially exceeding safe operating limits, leading to degraded device performance or even damage. Mutual dissipation, on the other hand, refers to the situation where, in a compact configuration or sharing a heat dissipation structure, the heat from one chip affects other nearby chips. For example, in high-density integrated circuits, multiple chips or functional modules may be arranged in a tight space, and heat transfer between them can affect each other, causing some chips to overheat and impacting the overall stability and performance of the system.

[0130] In another feasible implementation, the temperature rise of the power module consists of the temperature rise caused by the heat generated by the chips themselves and by the heat generated by other chips. The temperature rise caused by chip heat can be calculated based on the product of the corresponding chip's losses and thermal resistance. The temperature difference of each chip can be calculated based on the product of the corresponding chip's losses and thermal resistance. Since losses include the self-loss and mutual losses of each chip, and the thermal resistance parameters include the self-thermal resistance and mutual thermal resistance of each chip, a first temperature difference for each chip can be obtained based on the product of its self-loss and self-thermal resistance, and a second temperature difference for each chip can be obtained based on the product of its mutual losses and mutual thermal resistance; the sum of the first and second temperature differences for each chip yields the temperature difference of each chip; and the sum of the temperature differences of each chip determines the temperature difference of the power module.

[0131] It's important to note that self-thermal resistance refers to the resistance or resistance characteristic of heat transfer and distribution within a chip after heat is generated inside the chip. When current flows through a chip, resistance generates heat, which causes the internal temperature of the chip to rise. Self-thermal resistance describes the impact of this internal temperature rise on the chip's thermal characteristics. Self-thermal resistance typically refers to the internal thermal resistance of the chip, including how heat is transferred from active components (such as transistors) to the chip surface and how it is transferred to the environment through the chip package. Lower self-thermal resistance means that the chip can transfer heat to the surrounding environment more efficiently, thus maintaining a lower operating temperature. Mutual thermal resistance refers to the resistance or effect of heat transfer between chips in a multi-chip or multi-device module. This parameter describes the ease or difficulty of heat transfer between different chips. Mutual thermal resistance affects the temperature distribution and thermal balance of the various components of the entire module. Higher mutual thermal resistance leads to lower thermal coupling efficiency between chips, which may cause some chips to overheat or the overall system to have uneven thermal performance. In other words, self-thermal resistance describes the resistance characteristics of heat generation and transfer within a chip, while mutual thermal resistance describes the resistance characteristics of heat transfer between multiple chips. By setting self-thermal resistance and mutual thermal resistance, the operating temperature of the device can be effectively managed and controlled to improve reliability and performance.

[0132] Step S32: Determine the junction temperature of the power module based on the sampling temperature of the power module and the temperature difference.

[0133] In one feasible implementation, the junction temperature of the power module can be obtained from the sum of the sampling temperature and the temperature difference of the power module, specifically referring to formula (3).

[0134]

[0135] Among them, P UH ~P WL The losses of each chip in the six bridge arms are calculated using a loss calculation model. ntc_U ~T ntc_W This is the three-phase NTC sampling data for the power module. R UH_UH ~R wLine_WL These are thermal resistance parameters, which include not only the individual thermal resistances and mutual thermal resistances of each chip, but also line resistance, etc. T UH ~T WL This refers to the junction temperature of each chip in the power module.

[0136] In this embodiment, for power modules with HPD packages commonly used in electronic control, the thermal coupling between different bridge arm chips is decoupled, and a decoupled thermal resistance model is constructed. This improves the applicability, accuracy, and robustness of the junction temperature estimation scheme, making it suitable for various complex operating conditions of vehicles.

[0137] This application also provides a junction temperature estimation device for a power module, please refer to... Figure 4 The junction temperature estimation device for the power module includes:

[0138] The target loss calculation model determination module 10 is used to determine the target loss calculation model based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model.

[0139] Optionally, the target loss calculation model determination module 10 is further configured to determine the target loss calculation model as the instantaneous loss calculation model when the motor output frequency is less than the preset frequency; or, when the motor output frequency is greater than or equal to the preset frequency, determine the target loss calculation model as the average loss calculation model.

[0140] The loss determination module 20 is used to determine the loss of the power module in the motor controller based on the target loss calculation model and the motor operating parameters.

[0141] Optionally, the loss determination module 20 is further configured to, when the target loss calculation model is the instantaneous loss calculation model, obtain the first motor operating parameters and the instantaneous loss coefficient of the power module; perform loss calculation based on the first motor operating parameters and the instantaneous loss coefficient, and determine the instantaneous loss of the power module.

[0142] Optionally, the loss determination module 20 is further configured to, when the target loss calculation model is the average loss calculation model, obtain the second motor operating parameters and the average loss coefficient of the power module; perform loss calculation based on the second motor operating parameters and the average loss coefficient to determine the average loss of the power module.

[0143] Junction temperature determination module 30 is used to input the power module's losses into the thermal circuit model to estimate the junction temperature and obtain the junction temperature of the power module.

[0144] Optionally, the junction temperature determination module 30 is further configured to input the power module loss into the thermal circuit model to obtain the temperature difference of the power module; and determine the junction temperature of the power module based on the sampling temperature of the power module and the temperature difference.

[0145] Optionally, the junction temperature determination module 30 is further configured to acquire the temperature rise of each chip in the power module when it heats up and the losses of each chip; determine the self-thermal resistance of each chip based on the temperature rise and corresponding losses of each chip when it heats up; acquire the thermal conduction temperature rise of the current chip caused by the heat of other chips and the losses of the other chips; determine the mutual thermal resistance of the other chips relative to the current chip based on the thermal conduction temperature rise and the losses of the other chips; and construct the thermal path model based on the self-thermal resistance and mutual thermal resistance of each chip.

[0146] Optionally, the losses include the self-loss and mutual loss of each chip, the thermal resistance parameters include the self-thermal resistance and mutual thermal resistance of each chip, and the junction temperature determination module 30 is further configured to obtain a first temperature difference of each chip based on the product of the self-loss and self-thermal resistance of each chip, and to obtain a second temperature difference of each chip based on the product of the mutual loss and mutual thermal resistance of each chip; to obtain the temperature difference of each chip based on the sum of the first temperature difference and the second temperature difference of each chip; and to determine the temperature difference of the power module based on the sum of the temperature differences of each chip.

[0147] The junction temperature estimation device for power modules provided in this application employs the junction temperature estimation method for power modules in the above embodiments, and is applicable to junction temperature estimation of power modules under different operating conditions. Compared with the prior art, the beneficial effects of the junction temperature estimation device for power modules provided in this application are the same as those of the junction temperature estimation method for power modules provided in the above embodiments, and other technical features in the junction temperature estimation device for power modules are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0148] This application provides a motor controller, referenced... Figure 5 It shows a schematic diagram of a motor controller suitable for implementing the embodiments of this application. Figure 5 The motor controller shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of this application.

[0149] The motor controller includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enable the at least one processor to perform the junction temperature estimation method for the power module in Embodiment 1 described above.

[0150] The motor controller provided in this application employs the junction temperature estimation method for the power module in the above embodiments, which is applicable to the junction temperature estimation of the power module under different operating conditions. Compared with the prior art, the beneficial effects of the motor controller provided in this application are the same as those of the junction temperature estimation method for the power module provided in the above embodiments, and other technical features of this motor controller are the same as those disclosed in the method of the previous embodiment, and will not be repeated here.

[0151] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0152] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0153] This application also provides a vehicle that includes the aforementioned motor controller.

[0154] The vehicle provided in this application uses the junction temperature estimation method for the power module in the above embodiments, which is applicable to the estimation of the junction temperature of the power module under different operating conditions. Compared with the prior art, the beneficial effects of the vehicle provided in this application are the same as those of the junction temperature estimation method for the power module provided in the above embodiments, and other technical features of the electric vehicle are the same as those disclosed in the method of the previous embodiment, and will not be repeated here.

[0155] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the power module junction temperature estimation method as described above.

[0156] The computer program product provided in this application can be used to estimate the junction temperature of power modules under different operating conditions. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the junction temperature estimation method for power modules provided in the above embodiments, and will not be repeated here.

[0157] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A method for estimating the junction temperature of a power module, characterized in that, The method includes: The target loss calculation model is determined based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model; Based on the target loss calculation model and motor operating parameters, the loss of the power module in the motor controller is determined; The power module's losses are input into the thermal circuit model to estimate the junction temperature, thereby obtaining the junction temperature of the power module. The thermal circuit model is constructed based on the thermal resistance parameters of the power module.

2. The method as described in claim 1, characterized in that, The steps for determining the target loss calculation model based on the motor output frequency include: When the motor output frequency is less than the preset frequency, the target loss calculation model is determined to be the instantaneous loss calculation model; Alternatively, when the motor output frequency is greater than or equal to the preset frequency, the target loss calculation model is determined to be the average loss calculation model.

3. The method as described in claim 1, characterized in that, The step of determining the power module loss in the motor controller based on the target loss calculation model and motor operating parameters includes: When the target loss calculation model is the instantaneous loss calculation model, the operating parameters of the first motor and the instantaneous loss coefficient of the power module are obtained; The instantaneous loss of the power module is determined by calculating the loss based on the operating parameters of the first motor and the instantaneous loss coefficient.

4. The method as described in claim 1, characterized in that, The step of determining the power module loss in the motor controller based on the target loss calculation model and motor operating parameters includes: When the target loss calculation model is the average loss calculation model, the second motor operating parameters and the average loss coefficient of the power module are obtained. The average loss of the power module is determined by calculating the loss based on the operating parameters of the second motor and the average loss coefficient.

5. The method according to any one of claims 1 to 4, characterized in that, The step of inputting the power module's losses into a thermal circuit model to estimate the junction temperature and obtain the power module's junction temperature includes: The power module loss is input into the thermal circuit model to obtain the temperature difference of the power module; The junction temperature of the power module is determined based on the sampling temperature of the power module and the temperature difference.

6. The method as described in claim 5, characterized in that, The method further includes: The temperature rise of each chip in the power module when it generates heat and the loss of each chip are obtained. The self-thermal resistance of each chip is determined based on the temperature rise and corresponding losses when each chip generates its own heat. The thermal conduction temperature rise of the current chip due to the heat generated by other chips, as well as the losses of the other chips, are obtained. Based on the heat conduction temperature rise and the losses of the other chips, determine the mutual thermal resistance of the other chips relative to the current chip; The thermal circuit model is constructed based on the self-thermal resistance and mutual thermal resistance of each chip.

7. The method as described in claim 5, characterized in that, The losses include the self-loss and mutual loss of each chip, and the thermal resistance parameters include the self-thermal resistance and mutual thermal resistance of each chip. The step of inputting the losses of the power module into the thermal circuit model to obtain the temperature difference of the power module includes: The first temperature difference of each chip is obtained by multiplying the self-loss and self-thermal resistance of each chip, and the second temperature difference of each chip is obtained by multiplying the mutual loss and mutual thermal resistance of each chip. The temperature difference of each chip is obtained by summing the first and second temperature differences of each chip. The temperature difference of the power module is determined by summing the temperature differences of each chip.

8. A junction temperature estimation device for a power module, characterized in that, The device includes: The target loss calculation model determination module is used to determine the target loss calculation model based on the motor output frequency, wherein the target loss calculation model includes an instantaneous loss calculation model or an average loss calculation model. The loss determination module is used to determine the loss of the power module in the motor controller based on the target loss calculation model and the motor operating parameters. The junction temperature determination module is used to input the power module's losses into the thermal circuit model to estimate the junction temperature and obtain the junction temperature of the power module.

9. A motor controller, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the junction temperature estimation method for a power module as described in any one of claims 1 to 7.

10. A vehicle, characterized in that, The vehicle includes the motor controller as described in claim 7.

11. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the steps of the junction temperature estimation method for the power module as described in any one of claims 1 to 7.

Images