Motor controller, heating method for power battery pack and power assembly

Abstract

The present application provides a motor controller, a heating method for a power battery pack, a powertrain, and an electric vehicle, and relates to the technical field of electric vehicles. The input end of the motor controller is used to connect to the power battery pack, and the output end of the motor controller is used to connect to the motor. The motor controller includes an inverter and a controller. Among them, the input end of the inverter is used to connect to the input end of the motor controller, and the output end of the inverter is used to connect to the output end of the motor controller; the inverter is used to convert the direct current input from the power battery pack into a three-phase current and transmit it to the motor; the controller is used to control the working state of the inverter according to the current required motor heating power and the current required output torque of the motor, so as to adjust the three-phase current input from the inverter to the motor. By using this solution, there is no need to add a heating device for the power battery pack, which reduces space occupation, reduces costs, and improves the heating efficiency of the power battery pack.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to a motor controller, a heating method for a power battery pack, a powertrain, and an electric vehicle. Background Art

[0002] With the increasing energy shortage and environmental pollution problems in modern society, electric vehicles (EVs) have attracted widespread attention as new energy vehicles. Electric vehicles are powered by a battery pack, which in turn converts electrical energy into mechanical energy to drive the motor.

[0003] The discharge performance of electric vehicle power battery packs is poor at low temperatures. Therefore, efficient low-temperature heating measures are required to ensure that the power battery packs can operate within a safe temperature range to meet the charging and discharging requirements of the entire vehicle. Existing technologies heat power battery packs by adding heating devices.

[0004] See also Figure 1 , this figure is a schematic diagram of a heating device for a power battery pack provided by the prior art.

[0005] This heating device includes a positive temperature coefficient (PTC) resistor Rp and a controllable switch S. The PTC resistors Rp and S are connected in series and then in parallel with the electric vehicle's busbar capacitor Co. When the electric vehicle's battery management system (BMS) determines that the battery temperature is low, it controls the controllable switch S to close, connecting the PTC resistor Rp to the circuit to release heat, thereby heating the power battery pack. However, this heating method requires an additional heating device, which takes up space and increases cost. Summary of the Invention

[0006] In order to solve the above problems, the present application provides a motor controller, a heating method for a power battery pack, a power assembly and an electric vehicle, which do not require an additional heating device for the power battery pack, thereby reducing space occupation and lowering costs.

[0007] In the first aspect, the present application provides a motor controller, the input end of which is connected to a power battery pack, the output end of which is connected to a motor, and the motor controller includes an inverter and a controller. The input end of the inverter is connected to the input end of the motor controller, and the output end of the inverter is connected to the output end of the motor controller. The inverter is used to convert the direct current input from the power battery pack into a three-phase current and transmit it to the motor. When it is determined that the power battery pack needs to be heated, the controller controls the working state of the inverter according to the currently required motor heating power and the current output torque required by the motor to adjust the three-phase current output by the inverter to the motor.

[0008] The solution provided by this application reuses the motor controller and motor windings of an electric vehicle to heat the power battery pack, eliminating the need for additional heating equipment for the power battery pack, reducing space usage and lowering costs. Furthermore, the controller controls the three-phase current output by the inverter to the motor based on the current required motor heating power and the current required output torque of the motor. This adjusts the current flowing into the three-phase motor windings of the motor, changing the heating power of the motor windings and, in turn, the overall heating power of the motor. This means that the controller can optimize the heating power consumption of the power battery pack while meeting the current required output torque of the motor, thereby improving the heating efficiency of the power battery pack.

[0009] In one possible implementation, the controller is specifically used to determine the amplitude and phase of the input current of each phase motor winding based on the current required motor heating power and the current required output torque of the motor. The amplitude and phase of the input voltage of each phase motor winding are determined based on the amplitude and phase of the input current of each phase motor winding and the impedance of each phase motor winding. The input voltage of each phase motor winding is equal to the product of the input current of each phase motor winding and the impedance of each phase motor winding. The impedance of each phase motor winding is an inherent parameter of the motor winding and can be determined and stored in advance and called when the controller is used. The duty cycle of the control signal of the inverter is then determined based on the amplitude of the input voltage, and the sending time of the control signal is determined based on the phase of the input voltage, and the control signal is then used to control the working state of the inverter.

[0010] In one possible implementation, the controller determines the motor's excitation current and torque current based on the currently required motor heating power and the currently required motor output torque. Based on the excitation current and torque current, the controller determines the amplitude and phase of the input current to each phase of the motor winding. The excitation current is the d-axis current, and the torque current is the q-axis current. By adjusting the excitation current and torque current, the motor's heating power can be adjusted to the currently required motor heating power while still meeting the currently required motor output torque.

[0011] In a possible implementation, the controller is specifically configured to control the torque current to be zero and the excitation current to be a preset current when the output torque currently required by the motor is zero.

[0012] At this time, the electric vehicle is stationary and the motor does not need to output torque. In a preferred implementation, when the motor's excitation current is at a preset current, maximum heating power can be provided to the power battery pack. At this time, the d-axis current reaches its maximum value, which is the preset current, increasing the motor's power consumption to its maximum value. At this time, the heating rate of the power battery pack is the fastest, and the temperature of the power battery pack can be increased in the shortest possible time.

[0013] In a possible implementation, the controller is specifically configured to determine the currently required motor heating power and the currently required output torque of the motor according to the acquired torque command.

[0014] The torque instruction is used to indicate the output torque required by the current motor. The correspondence between the output torque required by the current motor and the current required motor heating power is pre-calibrated and stored in the storage module of the controller in the form of a data table, and is called when the controller is used.

[0015] In a possible implementation, the controller obtains a torque instruction from a vehicle controller VCU or a power management system PMS.

[0016] In one possible implementation, the controller is specifically used to determine the currently required motor heating power and the currently required output torque of the motor based on the torque command and temperature information, and the temperature information is used to indicate the current temperature of the power battery pack.

[0017] The torque command indicates the current motor output torque required, and the temperature information indicates the current battery pack temperature. The correspondence between the current motor output torque, the current motor heating power required, and the battery pack temperature is pre-calibrated and stored in the controller's storage module as a data table, which is then retrieved by the controller when it is used. The current motor heating power required is determined by the current motor output torque and the battery pack temperature, which in turn determines the battery pack heating rate. This optimizes the battery pack heating rate while also controlling motor power consumption.

[0018] In a possible implementation, the controller obtains a torque instruction from a vehicle controller VCU or a power management system PMS, and obtains temperature information from a battery management system BMS or the VCU.

[0019] In one possible implementation, the controller is specifically used to determine the output torque currently required by the motor based on the torque instruction, and determine the currently required motor heating power based on the obtained heating instruction, where the heating instruction is used to indicate the size of the currently required motor heating power.

[0020] In a possible implementation, the controller obtains a torque instruction from a vehicle controller VCU or a power management system PMS, and obtains a heating instruction from the VCU.

[0021] In a possible implementation, the inverter is a three-phase two-level inverter or a three-phase three-level inverter.

[0022] In a second aspect, the present application also provides a method for heating a power battery pack, which is used to heat the power battery pack by controlling a motor controller, wherein the input end of the motor controller is connected to the power battery pack, the output end of the motor controller is connected to the motor, the input end of the inverter included in the motor controller is connected to the input end of the motor controller, and the output end of the inverter is connected to the output end of the motor controller. The inverter is used to convert the DC power input from the power battery pack into a three-phase current and transmit it to the motor. The method includes:

[0023] Determine the current required motor heating power and the current motor output torque required;

[0024] According to the current required motor heating power and the current required output torque of the motor, the working state of the inverter is controlled to adjust the three-phase current input by the inverter to the motor.

[0025] This method reuses the electric vehicle's motor controller and motor windings to heat the power battery pack, eliminating the need for additional heating equipment for the power battery pack, reducing space usage and lowering costs. Furthermore, this method controls the three-phase current output by the inverter to the motor based on the current required motor heating power and the current required motor output torque. This adjusts the current flowing into the three-phase motor windings, changing the heating power of the motor windings and, in turn, the overall motor heating power. This optimizes the power battery pack's heating power consumption while maintaining the current required motor output torque, thereby improving the heating efficiency of the power battery pack.

[0026] In one possible implementation, the inverter's operating state is controlled based on the currently required motor heating power and the currently required motor output torque to adjust the three-phase current input from the inverter to the motor. Specifically, the control includes:

[0027] Determine the amplitude and phase of the input current of each phase motor winding according to the current required motor heating power and the current required output torque of the motor;

[0028] determining the amplitude and phase of the input voltage of each phase motor winding according to the amplitude and phase of the input current of each phase motor winding and the impedance of each phase motor winding;

[0029] Determining the duty cycle of the control signal of the inverter according to the amplitude of the input voltage, and determining the sending time of the control signal according to the phase of the input voltage;

[0030] The control signal is used to control the working state of the inverter.

[0031] In one possible implementation, the amplitude and phase of the input current of each phase motor winding are determined based on the currently required motor heating power and the currently required output torque of the motor, specifically including:

[0032] Determine the excitation current and torque current of the motor based on the current required motor heating power and the current required output torque of the motor. The excitation current is the d-axis current, and the torque current is the q-axis current.

[0033] The amplitude and phase of the input current of each phase motor winding are determined according to the excitation current and the torque current.

[0034] In one possible implementation, the excitation current and torque current of the motor are determined according to the currently required motor heating power and the currently required output torque of the motor, specifically including:

[0035] When the output torque currently required by the motor is zero, the torque current is controlled to be zero, and the excitation current is controlled to be a preset current.

[0036] In one possible implementation, determining the currently required motor heating power and the currently required output torque of the motor includes:

[0037] The currently required motor heating power and the currently required output torque of the motor are determined based on the obtained torque command.

[0038] The torque command can be sent by the VCU or PMS to indicate the output torque required by the current motor. The correspondence between the output torque required by the current motor and the current required motor heating power is pre-calibrated and disassembled in the form of a data table for call when used.

[0039] In one possible implementation, determining the currently required motor heating power and the currently required output torque of the motor includes:

[0040] Based on the torque command and temperature information, the currently required motor heating power and the current output torque required by the motor are determined. The temperature information is used to indicate the current temperature of the power battery pack.

[0041] The torque command can be obtained from the VCU or PMS, and the temperature information can be obtained from the BMS or VCU, which are not specifically limited in this embodiment of the application. The torque command is used to indicate the current output torque required by the motor, and the temperature information is used to indicate the current temperature of the power battery pack. The correspondence between the current output torque required by the motor, the current required motor heating power, and the power battery pack temperature is pre-calibrated and stored in the form of a data table for reference when needed.

[0042] In one possible implementation, determining the currently required motor heating power and the currently required output torque of the motor includes:

[0043] The output torque currently required by the motor is determined according to the torque instruction, and the currently required motor heating power is determined according to the obtained heating instruction. The heating instruction is used to indicate the size of the currently required motor heating power.

[0044] Torque commands can be obtained from the VCU or PMS, and heating commands can be obtained from the VCU. In some embodiments, the driver can determine the heating level for the power battery pack based on demand (a higher heating level results in a faster heating rate) or adjust the heating time for the power battery pack (a shorter heating time corresponds to a higher heating level). In response to the driver's input, the VCU determines the corresponding heating command based on the current power battery pack temperature information.

[0045] In a third aspect, the present application further provides a powertrain comprising the motor controller provided in the above implementation and a motor. The output of the motor controller is connected to the input of the motor. The motor is configured to convert electrical energy into mechanical energy to drive the electric vehicle.

[0046] This powertrain utilizes the motor controller provided in the above embodiments, optimizing the heating power consumption of the power battery pack while maintaining the required output torque of the motor. This improves the heating efficiency of the power battery pack. Furthermore, it avoids the need for additional heating devices to heat the power battery pack, reducing powertrain costs and facilitating miniaturization and high-integration design.

[0047] In some embodiments, the powertrain further includes: a first cooling circuit, a second cooling circuit, a pump device, and a heat exchanger.

[0048] The first cooling circuit performs heat exchange on the motor. The cooling medium in the first cooling circuit absorbs heat generated by the motor. The cooling medium in the first cooling circuit then passes through the heat exchanger to transfer the heat to the cooling medium in the second cooling circuit.

[0049] The coolant in the second cooling circuit first absorbs the heat of the motor controller, and then absorbs the heat transferred by the coolant in the first cooling circuit when passing through the heat exchanger, so that the temperature is fully increased, and then passes through the power battery pack to heat the power battery pack.

[0050] Fourthly, the present application also provides an electric vehicle, which includes the powertrain provided by the above implementation method and also includes a power battery pack. The power battery pack is connected to the input terminal of the motor controller, and the power battery pack is used to provide direct current to the motor controller. The powertrain of the electric vehicle applies the motor controller provided by the above embodiment, which can optimize and adjust the heating power consumption of the power battery pack while meeting the output torque required by the current motor, thereby improving the heating efficiency of the power battery pack. In addition, it avoids the need to add an additional heating device to heat the power battery pack, facilitates the miniaturization and high-integration design of the powertrain, and reduces the cost of the electric vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic diagram of a heating device for a power battery pack provided by the prior art;

[0052] Figure 2 A schematic diagram of an exemplary electric vehicle drive system provided in an embodiment of the present application;

[0053] Figure 3 A schematic diagram of a motor controller provided in an embodiment of the present application;

[0054] Figure 4 A schematic diagram of a cooling circuit provided in an embodiment of the present application;

[0055] Figure 5 A flowchart of a method for heating a power battery pack provided in an embodiment of the present application;

[0056] Figure 6 A schematic diagram of a powertrain provided in an embodiment of the present application;

[0057] Figure 7 A schematic diagram of an electric vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0058] In order to enable those skilled in the art to more clearly understand the technical solutions provided by the embodiments of the present application, the application scenarios of the technical solutions provided by the present application are first introduced below.

[0059] See also Figure 2 , which is a schematic diagram of an exemplary electric vehicle drive system provided in an embodiment of the present application.

[0060] The drive system includes a power battery pack, a motor controller 20 , a motor 30 , a DC (Direct Current) / DC converter 40 , a battery management system 60 and an on-board charger 70 .

[0061] Among them, the power battery pack 10 of the electric vehicle is used to provide high-voltage direct current. Part of the direct current is converted into alternating current through the motor controller 20 and provided to the motor 30, and the other part of the direct current is provided to the low-voltage battery 50 and the low-voltage system of the electric vehicle through the DC / DC converter 40.

[0062] When the electric vehicle is charging, the onboard charger 70 is connected to an external power source to charge the power battery pack 10 .

[0063] In some embodiments, the on-board charger 70 can also charge the low-voltage battery 50 at the same time.

[0064] The battery management system 60 is a functional unit that monitors and manages the charge and discharge of the power battery pack 10 , and is used to ensure that the power battery pack 10 is in a safe and controllable state.

[0065] The battery management system 60 may have functions such as battery state estimation, battery balancing, safety monitoring, thermal management, charge and discharge management, and information recording.

[0066] The state estimation refers to a functional unit that estimates the current capacity, state of charge (SOC), available power, and available energy of the power battery pack 10 .

[0067] Battery balancing refers to balancing the charge of each battery module by controlling the balancing circuit.

[0068] Safety monitoring refers to monitoring the power battery pack 10 for overvoltage, overcurrent, undervoltage, overtemperature, low temperature, and faults (short circuit, open circuit, etc.).

[0069] Thermal management refers to assisting in controlling the temperature of the power battery pack 10 to be within a preset temperature range, so as to improve the charge and discharge efficiency of the power battery pack 10 and extend the life of the power battery pack 10 .

[0070] Charge and discharge management refers to ensuring that the charge level is maintained within a reasonable range to prevent overcharging or overdischarging from damaging the power battery pack 10 .

[0071] Information logging refers to recording collected data and fault conditions.

[0072] In addition, electric vehicles also include a power management system (PMS), which can control the output power of the power battery pack and the power of the motor.

[0073] The technical solutions provided in the embodiments of this application primarily involve thermal management of the power battery pack 10, specifically the BMS and PMS described above. When an electric vehicle is started in a low-temperature environment (e.g., a cold winter), the power battery pack 10 is in a low-temperature state, resulting in poor discharge performance. Therefore, heating the power battery pack is necessary to improve its electrochemical performance.

[0074] Generally speaking, the power battery pack is heated before the electric vehicle begins driving. During driving, the power battery pack continues to supply power, and the heat generated by itself can be used to maintain the temperature. In some extremely cold environments, such as extremely low temperatures, or when the vehicle is running at low speeds, the power battery pack generates less heat, so heating is still necessary.

[0075] The existing technology can use a heating device to heat the power battery pack, but this method requires adding an additional heating device and then using the principle of positive temperature coefficient resistance heating to achieve heating, which takes up space in the electric vehicle and increases costs.

[0076] To address the aforementioned issues, this application provides a motor controller, a method for heating a power battery pack, a powertrain, and an electric vehicle. The solution provided by this application heats the power battery pack by reusing the motor controller and motor of the electric vehicle, eliminating the need for additional heating equipment for the power battery pack, reducing space usage and lowering costs. Furthermore, the three-phase current output by the motor controller to the motor can be adjusted based on the motor torque and required motor heating power, thereby optimizing the heating effect and improving the heating efficiency of the power battery pack.

[0077] The terms "first" and "second" in the following description of this application are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0078] In the following description of this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integrated connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0079] See also Figure 3 , which is a schematic diagram of a motor controller provided in an embodiment of the present application.

[0080] As shown, the input of the motor controller 20 is connected to the power battery pack 10, and the output is connected to the motor 30. The motor controller 20 is used to output three-phase current to the motor 30. That is, the three output ports of the motor controller 20 are respectively connected to a phase of the motor winding of the motor 30. The three phases of the motor 30 are represented by U phase, V phase, and W phase in the figure.

[0081] The motor controller 20 includes an inverter 201 and a controller 202 .

[0082] The inverter 201 is used to convert the direct current input from the power battery pack into a three-phase current and transmit it to the motor 30 .

[0083] The controller 202 controls the working state of the inverter 201 according to the currently required motor heating power and the currently required output torque of the motor, so as to adjust the three-phase current input by the inverter 201 to the motor 30 .

[0084] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the principle of using a motor and a motor controller to generate heat to heat a power battery pack will be first described below.

[0085] For the motor 30 , the utilized losses generally include copper loss and permanent magnet loss.

[0086] The copper loss of the motor refers to the heat generated by the current passing through the copper conductor. Where I1 is the current flowing through the copper conductor, and R1 is the resistance of the copper conductor.

[0087] The permanent magnet loss is caused by the electrical conductivity of the permanent magnet material of the motor, which will induce eddy current in the alternating magnetic field, thereby generating corresponding eddy current loss. The heat power of the permanent magnet loss is Where I2 is the current induced by the permanent magnet material, and R2 is the resistance of the eddy current circuit.

[0088] When the motor controller inputs DC power, the inverter of the motor controller includes power switching devices, such as Figure 3 The power switches T1-T6 in the motor generate heat. This is also known as the motor controller. When the motor controller inputs three-phase current to the motor, the motor generates heat due to the above losses.

[0089] Currently, electric vehicles are provided with a cooling system, which is used to cool the motor controller, the motor and the power battery pack. The following describes one implementation of the cooling system.

[0090] See also Figure 4 , which is a schematic diagram of a schematic cooling circuit provided in an embodiment of the present application.

[0091] The cooling system includes the following two cooling circuits: a first cooling circuit 401 and a second cooling circuit 402 .

[0092] The first cooling circuit 401 is used to exchange heat with the motor 30. Specifically, the motor 30's housing, shaft, and rotor core are provided with a cavity that communicates with the first cooling circuit 401. A cooling medium circulates within the first cooling circuit 401 to absorb heat generated by the motor. A pump device 403 is used to drive the cooling medium through the first cooling circuit 401.

[0093] The second cooling circuit 402 is used to exchange heat between the motor controller 20 and the power battery pack 10. Heat exchange can be performed between the second cooling circuit 402 and the first cooling circuit 401 via a heat exchanger 404. The heat exchanger 404 can also be referred to as a heat exchanger. The interfaces represented by A and B can be connected to the cooling system of the electric vehicle.

[0094] In some embodiments, the above cooling circuits can be used to cool the motor controller 20, the motor 30, and the power battery pack 10. However, when the temperature of the power battery pack 10 is significantly lower, the cooling medium in the second cooling circuit 402 first absorbs the heat of the motor controller 20, and then absorbs the heat of the cooling medium in the first cooling circuit 401 through the heat exchanger 404. The heat can then be transferred to the power battery pack 10, thereby heating the power battery pack 10. Therefore, the idea of the present application is to make full use of the heat generated by the motor controller 20 and the motor 30 to heat the power battery pack, and by adjusting the three-phase current input to the motor 30, change the heating power of the motor, thereby changing the heating speed of the power battery pack.

[0095] The above is merely an example of a possible implementation of the cooling system, and does not constitute a limitation on the technical solution of the present application.

[0096] The following describes the principle of changing the three-phase current input to the motor 30 to change the motor heating power.

[0097] Currently, a commonly used analysis method for the three-phase current input to the motor 30 is Park Transformation, which transforms the stationary three-phase coordinates into rotating dq-axis coordinates, thereby simplifying the analysis.

[0098] Among them, the d-axis (direct axis), also known as the direct axis, is parallel to the motor's rotation axis (magnetic pole axis). For a permanent magnet synchronous motor, the d-axis current is the excitation current.

[0099] The q-axis (quadrature axis), also known as the quadrature axis, is perpendicular to the magnetic pole axis of the motor, that is, perpendicular to the d-axis. The q-axis current is the torque current.

[0100] The formula of the motor electromagnetic torque Te is as follows:

[0101]

[0102] Where P is the number of pole pairs of the motor, Ψ f is the magnetic flux of the rotor, i d is the d-axis current, iq is the q-axis current, L d is the d-axis inductance, L q is the q-axis inductance.

[0103] The motor generally adopts a control method of maximum torque per ampere (MTPA) control or maximum torque per voltage (MTPV) control.

[0104] MTPA control requires generating maximum electromagnetic torque with minimum motor current. MTPV requires outputting maximum electromagnetic torque under existing bus voltage and speed conditions. The two control methods above determine the optimal q-axis and d-axis currents.

[0105] When the power battery pack needs to be heated, specifically in combination with formula (1), the d-axis current (i.e., i d The absolute value of the q-axis current increases, reducing the q-axis current. At this point, the d-axis and q-axis currents are no longer optimal, increasing motor power consumption and even increasing motor heat generation. The heat generated by the extra motor power consumption is then used to heat the battery pack.

[0106] The controller 202 controls the working state of the inverter 201 according to the currently required motor heating power and the current output torque required by the motor to adjust the three-phase current input by the inverter 201 to the motor, that is, adjusts the q-axis current and d-axis current of the motor at this time, changes the power consumption of the motor, and thus changes the heat generation of the motor.

[0107] The controller 202 in this embodiment can be an application specific integrated circuit (ASIC), a programmable logic device (PLD), a digital signal processor (DSP), or a combination thereof. The PLD can be a complex programmable logic device (CPLD), a field programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof, and is not specifically limited in this embodiment of the application.

[0108] Among them, the inverter 201 includes a power switching device, which can be an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET) or a silicon carbide metal oxide semiconductor (SiC MOSFET), etc., and the embodiment of the present application does not make specific limitations on this.

[0109] The controller 202 sends a pulse width modulation (PWM) signal to the power switch device of the inverter 201 to control the working state of the controllable switch. For example, the controller 202 changes the duty cycle of the control signal to change the on-time of the controllable switch.

[0110] The embodiment of the present application does not specifically limit the type of the inverter 201. Figure 3 In addition to the three-phase two-level inverter shown, a three-phase three-level inverter can also be used.

[0111] In summary, the solution provided by this application reuses the motor controller and motor windings of an electric vehicle to heat the power battery pack, eliminating the need for additional heating equipment for the power battery pack, reducing space usage and lowering costs. Furthermore, the controller controls the three-phase current output by the inverter to the motor based on the current required motor heating power and the current required output torque of the motor. This adjusts the current flowing into the three-phase motor windings of the motor, changes the heating power of the motor windings, and thus changes the overall heating power of the motor. Specifically, the controller can optimize the heating power consumption of the power battery pack while meeting the current required output torque of the motor, thereby improving the heating efficiency of the power battery pack.

[0112] Continue to see Figure 3 , the following is an explanation based on the specific working principle of the controller.

[0113] The following first describes how the controller 202 determines the currently required motor heating power and the currently required output torque of the motor.

[0114] In one possible implementation, the controller 202 determines the currently required motor heating power and the currently required output torque of the motor according to the acquired torque command.

[0115] The torque command may be sent by a vehicle control unit (VCU) or a PMS, and is not specifically limited in the embodiment of the present application.

[0116] The torque instruction is used to indicate the output torque required by the current motor. The correspondence between the output torque required by the current motor and the current required motor heating power is pre-calibrated and stored in the storage module of the controller 202 in the form of a data table, and is called when the controller is used.

[0117] The data table is in the form of a one-to-one correspondence between the output torque required by the current motor and the current required motor heating power, for example (T1, P1), (T2, P2), (T3, P3), ..., (Tn, Pn), where T1-Tn is the output torque required by the current motor, and P1-Pn is the current required motor heating power.

[0118] Among them, the storage module of the controller can be a non-volatile memory (NVM), such as a read-only memory (ROM), specifically an electrically erasable programmable read-only memory (EEROM) or an erasable programmable read-only memory (EPROM).

[0119] In some embodiments, referring to formula (1), when the motor is at the current required motor heating power, it can provide the maximum heating power for the power battery pack. At this time, increasing the d-axis current (i.e., i d The absolute value of the motor current increases), the q-axis current is reduced, and the total motor current is increased to the maximum value by redistributing the current, so that the motor power consumption is increased to the maximum value. At this time, the heating rate of the power battery pack is the fastest, and the temperature of the power battery pack can be increased in the shortest time.

[0120] In another possible implementation, the controller 202 determines the currently required motor heating power and the currently required output torque of the motor according to the torque command and the temperature information.

[0121] The controller 202 may obtain a torque instruction from the VCU or PMS, and obtain temperature information from the BMS or VCU, which is not specifically limited in the embodiment of the present application.

[0122] The torque command indicates the current motor output torque, and the temperature information indicates the current battery pack temperature. The correspondence between the current motor output torque, the current motor heating power, and the battery pack temperature is pre-calibrated and stored in the storage module of controller 202 in the form of a data table, which is then retrieved when the controller is used.

[0123] At this point, the current required motor heating power is determined by the current motor output torque and the power battery pack temperature. The data table format is, for example, (T1, t1, P11), (T1, t2, P12), ... (T1, tm, P1m), (T2, t1, P21), (T2, t2, P22), ..., (Tn, tm, Pnm), where T1-Tn is the current motor output torque, t1-tm is the power battery pack temperature, and P11-Pmn is the current required motor heating power.

[0124] The storage module of the controller 202 may be an NVM, such as a ROM, specifically an EEROM or an EPROM.

[0125] At this time, the output torque required by the different current motors and the temperature of the power battery pack jointly determine the current required motor heating power, which is equivalent to jointly determining the heating rate of the power battery pack, realizing the optimized adjustment of the heating rate of the power battery pack while taking into account the control of the motor power consumption.

[0126] In another possible implementation, the controller 202 determines the output torque currently required by the motor based on the torque instruction, and determines the currently required motor heating power based on the obtained heating instruction, where the heating instruction is used to indicate the magnitude of the currently required motor heating power.

[0127] Controller 202 receives torque commands from the VCU or PMS, and also receives heating commands from the VCU. In some embodiments, the driver can determine the heating level for the power battery pack (a higher heating level results in a faster heating rate) or adjust the heating time for the power battery pack based on demand (a shorter heating time corresponds to a higher heating level). In response to the driver's input, the VCU determines the corresponding heating command based on the current power battery pack temperature information and sends the heating command to the controller. The heating command indicates the current required motor heating power.

[0128] The principle of how the controller controls the working state of the inverter 202 is described below.

[0129] After the controller 202 determines the currently required motor heating power and the currently required output torque of the motor through the above implementation method, it determines the excitation current and torque current of the motor based on the currently required motor heating power and the currently required output torque of the motor, see formula (1), and determines the amplitude and phase of the input current of each phase motor winding based on the excitation current and the torque current. The excitation current is the d-axis current, and the torque current is the q-axis current.

[0130] Determine the magnitude and phase of the input current to each motor winding phase.

[0131] The controller 202 then determines the magnitude and phase of the input voltage to each phase of the motor winding based on the magnitude and phase of the input current to each phase of the motor winding and the impedance of each phase of the motor winding.

[0132] The input voltage of each phase motor winding is equal to the product of the input current of each phase motor winding and the impedance of each phase motor winding.

[0133] The impedance of each phase motor winding is an inherent parameter of the motor winding, which can be determined and stored in advance and called when the controller is used.

[0134] The controller 202 then determines the duty cycle of the control signal of the inverter according to the amplitude of the input voltage, and determines the sending time of the control signal according to the phase of the input voltage, and further controls the working state of the inverter 201 through the control signal.

[0135] The following describes two common application scenarios.

[0136] First, the electric vehicle is at rest.

[0137] Continuing to refer to formula (1), when the electric vehicle is stationary and the power battery pack is heated, the output torque required by the current motor is zero, that is, the electromagnetic torque Te is zero, the control torque current is zero, and the control excitation current is a preset current. This allows the power battery pack to be heated without the motor outputting torque.

[0138] The embodiment of the present application does not specifically limit the preset current. In a preferred implementation, when the excitation current of the motor is the preset current, the maximum heating power can be provided for the power battery pack. At this time, the d-axis current has a maximum value of the preset current, so that the power consumption of the motor increases to the maximum value. At this time, the heating rate of the power battery pack is the fastest, and the temperature of the power battery pack can be increased in the shortest time.

[0139] The second type is that the electric vehicle is in driving state.

[0140] At this time, in order to achieve heating of the power battery pack, part of the motor power is used to provide the currently required output torque, and the other part is used for heat generation. Under the premise of maintaining the same output torque, the motor current is redistributed through the relevant methods in the above embodiments so that i d The absolute value increases, i q If it decreases, the total motor current increases, which in turn increases the heat generated, thereby heating the power battery pack.

[0141] In summary, the solution provided by this application reuses the motor controller and motor windings of an electric vehicle to heat the power battery pack, eliminating the need for additional heating equipment for the power battery pack, reducing space usage and lowering costs. Furthermore, the controller controls the three-phase current output by the inverter to the motor based on the current required motor heating power and the current required output torque of the motor. This adjusts the current flowing into the three-phase motor windings of the motor, changes the heating power of the motor windings, and thus changes the overall heating power of the motor. Specifically, the controller can optimize the heating power consumption of the power battery pack while meeting the current required output torque of the motor, thereby improving the heating efficiency of the power battery pack.

[0142] Based on the motor controller provided in the above embodiments, an embodiment of the present application further provides a method for heating a power battery pack. This method controls the motor controller provided in the above embodiments to achieve heating of the power battery pack, which is described in detail below with reference to the accompanying drawings.

[0143] See also Figure 5 , which is a flow chart of a method for heating a power battery pack provided in an embodiment of the present application.

[0144] The method comprises the following steps:

[0145] S501: Determine the currently required motor heating power and the currently required output torque of the motor.

[0146] S502: Control the working state of the inverter according to the currently required motor heating power and the currently required output torque of the motor, so as to adjust the three-phase current inputted by the inverter to the motor.

[0147] The specific implementation of S501 is first described below.

[0148] In a possible implementation, the currently required motor heating power and the currently required output torque of the motor are determined based on the acquired torque command.

[0149] The torque instruction can be sent by the VCU or PMS, and is not specifically limited in this embodiment of the application.

[0150] The torque command is used to indicate the output torque required by the current motor. The corresponding relationship between the output torque required by the current motor and the current required motor heating power is pre-calibrated and removed in the form of a data table and called when needed.

[0151] The data table is in the form of a one-to-one correspondence between the output torque required by the current motor and the current required motor heating power, for example (T1, P1), (T2, P2), (T3, P3), ..., (Tn, Pn), where T1-Tn is the output torque required by the current motor, and P1-Pn is the current required motor heating power.

[0152] In some embodiments, referring to formula (1), when the motor is at the current required motor heating power, it can provide the maximum heating power for the power battery pack. At this time, increasing the d-axis current (i.e., i d The absolute value of the motor current increases), the q-axis current is reduced, and the total motor current is increased to the maximum value by redistributing the current, so that the motor power consumption is increased to the maximum value. At this time, the heating rate of the power battery pack is the fastest, and the temperature of the power battery pack can be increased in the shortest time.

[0153] In another possible implementation, the currently required motor heating power and the currently required output torque of the motor are determined based on the torque command and the temperature information.

[0154] The torque command can be obtained from the VCU or PMS, and the temperature information can be obtained from the BMS or VCU, which is not specifically limited in the embodiment of the present application.

[0155] The torque command indicates the current motor output torque, and the temperature information indicates the current battery pack temperature. The correspondence between the current motor output torque, the current motor heating power, and the battery pack temperature is pre-calibrated and stored in a data table for later use.

[0156] At this point, the current required motor heating power is determined by the current motor output torque and the power battery pack temperature. The data table format is, for example, (T1, t1, P11), (T1, t2, P12), ... (T1, tm, P1m), (T2, t1, P21), (T2, t2, P22), ..., (Tn, tm, Pnm), where T1-Tn is the current motor output torque, t1-tm is the power battery pack temperature, and P11-Pmn is the current required motor heating power.

[0157] At this time, the output torque required by the different current motors and the temperature of the power battery pack jointly determine the current required motor heating power, which is equivalent to jointly determining the heating rate of the power battery pack, realizing the optimized adjustment of the heating rate of the power battery pack while taking into account the control of the motor power consumption.

[0158] In another possible implementation, the output torque currently required by the motor is determined based on the torque instruction, and the currently required motor heating power is determined based on the obtained heating instruction, where the heating instruction is used to indicate the magnitude of the currently required motor heating power.

[0159] The torque command is obtained from the VCU or PMS, and the heating command is obtained from the VCU. In some embodiments, the driver can determine the heating level for the power battery pack based on demand (a higher heating level means a faster heating rate) or adjust the heating time for the power battery pack (a shorter heating time means a higher heating level). In response to the driver's input, the VCU combines the current power battery pack temperature information to determine the corresponding heating command, which indicates the current required motor heating power.

[0160] The specific implementation of S502 is described below.

[0161] After determining the current required motor heating power and the current required output torque of the motor through S501, the excitation current and torque current of the motor are determined based on the current required motor heating power and the current required output torque of the motor, referring to formula (1). Based on the excitation current and torque current, the amplitude and phase of the input current of each phase motor winding are determined. The excitation current is the d-axis current, and the torque current is the q-axis current.

[0162] Determine the magnitude and phase of the input current to each motor winding phase.

[0163] Then, the amplitude and phase of the input voltage of each phase motor winding are determined according to the amplitude and phase of the input current of each phase motor winding and the impedance of each phase motor winding.

[0164] The input voltage of each phase motor winding is equal to the product of the input current of each phase motor winding and the impedance of each phase motor winding.

[0165] The impedance of each phase motor winding is an inherent parameter of the motor winding and can be determined and stored in advance and called when needed.

[0166] The duty cycle of the control signal of the inverter is determined according to the amplitude of the input voltage, and the sending time of the control signal is determined according to the phase of the input voltage, and the working state of the inverter 201 is controlled by using the control signal.

[0167] When heating the power battery pack while the electric vehicle is stationary, the current motor output torque is zero, meaning the electromagnetic torque Te is zero, the torque control current is zero, and the excitation current is controlled to a preset current. This allows heating the power battery pack without the motor outputting torque. In a preferred implementation, when the motor excitation current is at a preset current, maximum heating power is provided to the power battery pack. At this time, the d-axis current reaches its maximum value, increasing the motor power consumption to its maximum value. This results in the fastest heating rate for the power battery pack, raising the power battery pack temperature in the shortest possible time.

[0168] The division of the above steps in the embodiment of the present application is only for the convenience of explanation and does not constitute a limitation to the present application.

[0169] In summary, the method provided by this application reuses the motor controller and motor windings of an electric vehicle to heat the power battery pack, eliminating the need for additional heating equipment for the power battery pack, reducing space usage and lowering costs. Furthermore, this method controls the three-phase current output by the inverter to the motor based on the current required motor heating power and the current required output torque of the motor. This adjusts the current flowing into the three-phase motor windings of the motor, thereby changing the heating power of the motor windings and, in turn, the overall heating power of the motor. This allows for optimal regulation of the power battery pack's heating power consumption while maintaining the current required output torque of the motor, thereby improving the heating efficiency of the power battery pack.

[0170] Based on the motor controller provided in the above embodiments, the embodiments of the present application further provide a powertrain for an electric vehicle, which will be described in detail below with reference to the accompanying drawings.

[0171] See also Figure 6 , which is a schematic diagram of a powertrain provided in an embodiment of the present application.

[0172] The powertrain 600 includes the motor controller 10 provided in the above embodiment and a motor 20. The output of the motor controller 10 is connected to the input of the motor 20. The motor 20 is used to convert electrical energy into mechanical energy to drive the electric vehicle.

[0173] The specific working principle of the motor controller 10 can be found in the description of the above embodiments, which will not be repeated here.

[0174] For further information, see Figure 4 The powertrain may further include: a first cooling circuit 401 , a second cooling circuit 402 , a pump device 403 and a heat exchanger 404 .

[0175] The following describes in detail the heating process of the power battery pack by the powertrain.

[0176] The circulation of the coolant in first cooling circuit 401 is shown by the dashed arrows in the figure. By performing heat exchange with motor 30, the coolant in first cooling circuit 401 absorbs the heat generated by the motor. The heat generation principle and process of the motor can be found in the relevant description of the above embodiments, and will not be repeated here in this embodiment of the present application. The coolant in first cooling circuit 401 then transfers the heat to the coolant in second cooling circuit 402 through heat exchanger 404.

[0177] The coolant in the second cooling circuit 402 flows in from point A, first absorbing heat from the motor controller 20. Then, while passing through the heat exchanger 404, it absorbs heat transferred from the coolant in the first cooling circuit 401, thereby sufficiently raising its temperature. The coolant then passes through the power battery pack 10, effectively heating the power battery pack 10. After heating the power battery pack 10, the coolant reaches point B. In some embodiments, points A and B can be connected to the radiator, cooling system, or other heat exchanger of the electric vehicle to form a circuit, which is not specifically limited in this embodiment of the present application.

[0178] In summary, the powertrain provided by the embodiment of the present application utilizes the motor controller provided by the above embodiment. The controller of the motor controller controls the three-phase current output by the inverter to the motor based on the current required motor heating power and the current required output torque of the motor. That is, the current flowing into the three-phase motor windings of the motor is adjusted, the heating power of the motor windings is changed, and the heating power of the motor as a whole is changed. That is, the controller can also optimize and adjust the heating power consumption of the power battery pack while meeting the output torque required by the current motor, thereby improving the heating efficiency of the power battery pack. In addition, it avoids the need for an additional heating device to heat the power battery pack, reduces the cost of the powertrain, and facilitates the design of a miniaturized and highly integrated powertrain.

[0179] Based on the motor controller and powertrain provided in the above embodiments, the embodiments of the present application further provide an electric vehicle, which will be described in detail below with reference to the accompanying drawings.

[0180] See also Figure 7 , which is a schematic diagram of an electric vehicle provided in an embodiment of the present application.

[0181] The electric vehicle 700 includes the powertrain 600 provided in the above embodiment, and also includes a power battery pack 10 .

[0182] The specific working principles of the powertrain 600 and the motor controller can be found in the relevant descriptions in the above embodiments, which will not be repeated here in this embodiment.

[0183] When heating the power battery pack when the electric vehicle is stationary, the output torque required by the current motor is zero, that is, the electromagnetic torque is zero at this time. The motor controller controls the torque current of the motor to be zero, and controls the excitation current to be a preset current. It is possible to heat the power battery pack without the motor outputting torque.

[0184] The embodiment of the present application does not specifically limit the preset current. In a preferred implementation, when the excitation current of the motor is the preset current, the maximum heating power can be provided for the power battery pack. At this time, the d-axis current has a maximum value of the preset current, so that the power consumption of the motor increases to the maximum value. At this time, the heating rate of the power battery pack is the fastest, and the temperature of the power battery pack can be increased in the shortest time.

[0185] When the electric vehicle is in motion, in order to heat the power battery pack, part of the motor power is used to provide the currently required output torque, and the other part is used for generating heat. Under the premise of maintaining the same output torque, the motor current is redistributed through the relevant methods in the above embodiments, so that the absolute value of the d-axis current increases, the q-axis current decreases, and the total motor current increases, thereby increasing the heat generation and heating the power battery pack.

[0186] In summary, the electric vehicle powertrain utilizes the motor controller provided in the above embodiments. This motor controller controls the three-phase current output by the inverter to the motor based on the currently required motor heating power and the current output torque required by the motor. This adjusts the current flowing into the three-phase motor windings of the motor, changes the heating power of the motor windings, and thus changes the overall heating power of the motor. This means the controller can also optimize the heating power consumption of the power battery pack while meeting the current output torque required by the motor, thereby improving the heating efficiency of the power battery pack. Furthermore, the need for an additional heating device to heat the power battery pack is avoided, facilitating a miniaturized and highly integrated design of the powertrain and reducing the cost of the electric vehicle.

[0187] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0188] Each embodiment in this specification is described in a progressive manner. Similar parts between the embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments. In addition, some or all of the units and modules can be selected according to actual needs to achieve the purpose of the embodiment. Those of ordinary skill in the art can understand and implement the present invention without inventive work.

[0189] The above is only a specific implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A motor controller, characterized in that: The input end of the motor controller is used to connect to the power battery pack, and the output end of the motor controller is used to connect to the motor. The motor controller includes an inverter and a controller. The inverter is used to convert the direct current input from the power battery pack into a three-phase current and transmit it to the motor; the input end of the inverter is used to connect to the input end of the motor controller, and the output end of the inverter is used to connect to the output end of the motor controller. The controller sends a pulse width modulation (PWM) signal to the inverter to control the working state of the inverter. The heat generated by the motor controller and the heat generated by the motor is used to transfer to the power battery pack to achieve heating of the power battery pack; The cooling system of the motor is used to communicate with the first cooling circuit of the vehicle, and the cooling medium of the first cooling circuit is used to absorb the heat generated by the motor and transfer it to the power battery pack for heating; The cooling system of the motor controller is used to communicate with the second cooling circuit of the vehicle, and the cooling medium of the second cooling circuit is used to absorb the heat generated by the motor controller and transfer it to the power battery pack for heating; The controller is configured to control the inverter to input a three-phase current to the motor to increase the heating rate of the power battery pack, wherein: When the vehicle is at rest, the controller controls the torque current to be zero and controls the excitation current to be equal to a current that can maximize the heat dissipation of the motor when the vehicle is at rest, the excitation current being the d-axis current and the torque current being the q-axis current; When the vehicle is in a driving state, the controller controls the absolute value of the excitation current to increase and the torque current value to decrease, controls the total current of the motor to increase, and controls the output torque of the motor to remain unchanged; The temperature of the power battery pack is lower than a preset temperature, and the second cooling circuit is used to absorb heat from the motor controller and heat from the first cooling circuit and transfer the heat to the power battery pack for heating.

2. The motor controller according to claim 1, characterized in that: The controller is specifically configured to determine the amplitude and phase of the input current of each phase motor winding according to the excitation current and the torque current; determining the amplitude and phase of the input voltage of each phase of the motor winding according to the amplitude and phase of the input current of each phase of the motor winding and the impedance of each phase of the motor winding; determining a duty cycle of a control signal of the inverter according to the amplitude of the input voltage, and determining a sending time of the control signal according to the phase of the input voltage; The control signal is used to control the working state of the inverter.

3. The motor controller according to claim 2, characterized in that: The controller determines the excitation current and torque current of the motor according to the currently required motor heating power and the currently required output torque of the motor.

4. The motor controller according to any one of claims 2 to 3, characterized in that: The controller is specifically used to determine the currently required motor heating power and the currently required output torque of the motor according to the acquired torque instruction.

5. The motor controller according to claim 4, characterized in that: The controller obtains the torque instruction from the vehicle controller VCU or the energy management system PMS.

6. The motor controller according to any one of claims 2 to 3, characterized in that: The controller is specifically used to determine the currently required motor heating power and the currently required output torque of the motor according to the torque command and temperature information, and the temperature information is used to indicate the current temperature of the power battery pack.

7. The motor controller according to claim 6, characterized in that: The controller obtains the torque instruction from a vehicle controller (VCU) or a power management system (PMS), and obtains the temperature information from a battery management system (BMS) or the VCU.

8. The motor controller according to any one of claims 2 to 3, characterized in that: The controller is specifically used to determine the output torque currently required by the motor according to the torque instruction, and to determine the currently required motor heating power according to the obtained heating instruction, wherein the heating instruction is used to indicate the magnitude of the currently required motor heating power.

9. The motor controller according to claim 8, characterized in that: The controller obtains the torque instruction from a vehicle controller (VCU) or a power management system (PMS), and obtains the heating instruction from the VCU.

10. The motor controller according to claim 1, characterized in that: The inverter is a three-phase two-level inverter or a three-phase three-level inverter.

11. A method for heating a power battery pack, for heating the power battery pack by controlling a motor controller, wherein the input end of the motor controller is connected to the power battery pack, the output end of the motor controller is connected to the motor, the input end of an inverter included in the motor controller is connected to the input end of the motor controller, and the output end of the inverter is connected to the output end of the motor controller, and the inverter is used to convert the direct current input from the power battery pack into a three-phase current and transmit it to the motor; characterized in that: The method comprises: When the vehicle is at rest, the torque current is controlled to be zero, and the excitation current is controlled to be equal to a current that can maximize the heat dissipation of the motor when the vehicle is at rest, the excitation current being the d-axis current and the torque current being the q-axis current; When the vehicle is in a driving state, controlling the absolute value of the excitation current to increase and the torque current value to decrease, controlling the total current of the motor to increase, and controlling the output torque of the motor to remain unchanged; According to the torque current and the excitation current, the inverter is controlled to input a three-phase current to the motor to increase the heating rate of the power battery pack. The controller sends a pulse width modulation (PWM) signal to the inverter to control the working state of the inverter. The heat generated by the motor controller and the heat generated by the motor are used to be transferred to the power battery pack to achieve heating of the power battery pack; the cooling system of the motor is used to be connected to the first cooling circuit of the vehicle, and the cooling medium of the first cooling circuit is used to absorb the heat generated by the motor and transfer it to the power battery pack for heating; the cooling system of the motor controller is used to be connected to the second cooling circuit of the vehicle, and the cooling medium of the second cooling circuit is used to absorb the heat generated by the motor controller and transfer it to the power battery pack for heating; the temperature of the power battery pack is lower than the preset temperature, and the second cooling circuit is used to absorb the heat of the motor controller and the heat of the first cooling circuit and transfer them to the power battery pack for heating.

12. The method for heating a power battery pack according to claim 11, characterized in that: The step of controlling the working state of the inverter according to the torque current and the excitation current to adjust the three-phase current input by the inverter to the motor specifically includes: Determining the amplitude and phase of the input current of each phase motor winding according to the excitation current and the torque current; determining the amplitude and phase of the input voltage of each phase of the motor winding according to the amplitude and phase of the input current of each phase of the motor winding and the impedance of each phase of the motor winding; determining a duty cycle of a control signal of the inverter according to the amplitude of the input voltage, and determining a sending time of the control signal according to the phase of the input voltage; The control signal is used to control the working state of the inverter.

13. The method for heating a power battery pack according to claim 12, wherein: Before determining the amplitude and phase of the input current of each phase motor winding according to the excitation current and the torque current, the method further includes: The excitation current and torque current of the motor are determined according to the currently required motor heating power and the currently required output torque of the motor.

14. The method for heating a power battery pack according to any one of claims 12 to 13, characterized in that: Determining the current required motor heating power and the current required motor output torque includes: The currently required motor heating power and the currently required output torque of the motor are determined based on the obtained torque command.

15. The method for heating a power battery pack according to any one of claims 12 to 13, characterized in that: Determining the current required motor heating power and the current required motor output torque includes: The currently required motor heating power and the currently required output torque of the motor are determined according to the torque command and the temperature information, wherein the temperature information is used to indicate the current temperature of the power battery pack.

16. The method for heating a power battery pack according to any one of claims 12 to 13, characterized in that: Determining the current required motor heating power and the current required motor output torque includes: The output torque currently required by the motor is determined according to the torque instruction, and the currently required motor heating power is determined according to the obtained heating instruction, wherein the heating instruction is used to indicate the magnitude of the currently required motor heating power.

17. A powertrain, characterized in that: The powertrain comprises a motor controller and a motor according to any one of claims 1 to 10, wherein: The output end of the motor controller is connected to the input end of the motor; The motor is used to convert electrical energy into mechanical energy to drive the electric vehicle.

18. An electric vehicle, characterized in that: The electric vehicle comprises the powertrain and power battery pack according to claim 17, wherein: The power battery pack is connected to the input end of the motor controller; The power battery pack is used to provide direct current to the motor controller.

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