Motor control method and device, electronic equipment and readable medium

Abstract

The invention provides a motor control method and device, electronic equipment and a readable medium. The method comprises the steps that the initial voltage and the target heating value of a driving motor of the vehicle are obtained, the working torque of the driving motor is determined, and the initial voltage is lower than or equal to the voltage of a power battery of the vehicle; if the target calorific value is higher than the calorific value threshold value, the boost voltage of the driving motor is determined according to the working torque of the driving motor, the vehicle speed of the vehicle and a boost voltage relation table, the boost voltage is higher than the voltage of a power battery, and the boost voltage relation table comprises the corresponding relation between the vehicle speed and the motor torque and the boost voltage; determining a target working voltage according to the boosting voltage of the driving motor and the target heating value; and outputting the target working voltage to the driving motor. The method can ensure the working temperature of the power battery and improve the use experience of the vehicle.

Description

Technical Field

[0001] The present application relates to the field of new energy vehicles, and in particular to a motor control method, device, electronic device and readable medium. Background Art

[0002] The performance degradation of batteries in new energy vehicles in low temperature environments has always been a difficulty faced by the new energy vehicle field. Therefore, how to maintain the temperature of power batteries in new energy vehicles in low temperature environments has become an important problem to be solved.

[0003] In the related art, the thermal management water circuit is connected in series with the water circuit of the drive motor, and the thermal energy generated by the drive motor during parking and driving is recovered through a thermal management integrated module to heat the power battery or the passenger compartment.

[0004] However, in this type of solution, the heat generation capacity of the drive motor is limited. In low-temperature environments, insufficient heat generation may occur, resulting in reduced heating effect, so that the battery cannot be heated to the predetermined temperature and performance is reduced, affecting the vehicle's user experience. Summary of the invention

[0005] Based on the above technical problems, the present application provides a motor control method, device, electronic device and readable medium to ensure the operating temperature of the power battery and improve the vehicle's user experience.

[0006] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0007] According to one aspect of an embodiment of the present application, there is provided a motor control method, comprising:

[0008] Obtaining an initial voltage and a target heat value of a driving motor of the vehicle and determining a working torque of the driving motor, wherein the initial voltage is lower than or equal to a voltage of a power battery of the vehicle;

[0009] If the target heating value is higher than the heating value threshold, the boost voltage of the drive motor is determined according to the working torque of the drive motor, the vehicle speed, and a boost voltage relationship table, wherein the boost voltage is higher than the voltage of the power battery, and the boost voltage relationship table includes a correspondence between the vehicle speed, the motor torque, and the boost voltage;

[0010] Determining a target operating voltage according to the boost voltage of the drive motor and the target heating value;

[0011] The target operating voltage is output to the driving motor.

[0012] According to one aspect of an embodiment of the present application, there is provided a motor control device, comprising:

[0013] A data acquisition module, configured to acquire an initial voltage and a target heating value of a driving motor of the vehicle and determine a working torque of the driving motor, wherein the initial voltage is lower than or equal to a voltage of a power battery of the vehicle;

[0014] a boost module, configured to determine a boost voltage of the drive motor according to the working torque of the drive motor, the speed of the vehicle, and a boost voltage relationship table if the target heat value is higher than a heat value threshold, wherein the boost voltage is higher than the voltage of the power battery, and the boost voltage relationship table includes a correspondence between the vehicle speed and the motor torque and the boost voltage;

[0015] A voltage determination module, configured to determine a target operating voltage according to the boost voltage of the drive motor and the target heating value;

[0016] A voltage output module is configured to output the target operating voltage to the drive motor.

[0017] In some embodiments of the present application, based on the above technical solution, the voltage determination module is specifically configured to: determine the quadrature-axis current and the direct-axis current under the boost voltage according to the boost voltage and the motor speed of the drive motor; determine the target operating voltage according to the current torque curve and the mapping relationship between the quadrature-axis current and the direct-axis current under the boost voltage, and the current torque curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current of the drive motor at the operating torque.

[0018] In some embodiments of the present application, based on the above technical solution, the data acquisition module is specifically configured to: obtain the current vehicle speed and accelerator pedal opening of the vehicle; obtain the wheel-end required torque corresponding to the current vehicle speed and the accelerator pedal opening according to the pedal characteristic mapping, and the pedal characteristic mapping is used to represent the mapping relationship between the wheel-end required torque and the accelerator pedal opening; determine the working torque of the drive motor according to the wheel-end required torque and the transmission efficiency of the vehicle.

[0019] In some embodiments of the present application, based on the above technical solution, the voltage determination module is specifically configured to: determine the current torque curve of the drive motor according to the working torque of the drive motor, and the current torque curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current of the drive motor at the working torque; determine the voltage limit curve of the vehicle according to the boost voltage and the motor speed of the drive motor, and the voltage limit curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current under the boost voltage; determine the target working voltage according to the voltage limit curve and the current torque curve of the drive motor.

[0020] In some embodiments of the present application, based on the above technical solution, the voltage limit curve is an elliptical curve, and the voltage determination module is specifically configured to: determine the current limit curve of the vehicle according to the maximum allowable current of the drive motor, wherein the current limit curve is a circular curve and is used to represent the mapping relationship between the cross-axis current and the direct-axis current of the drive motor at the maximum allowable current; if the voltage limit curve and the current limit curve are in an intersecting relationship, then determine the target operating voltage according to the current limit curve and the current torque curve of the drive motor.

[0021] In some embodiments of the present application, based on the above technical solution, the voltage determination module is further configured as follows: if the current limit curve contains the voltage limit curve, then in the current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor, according to the intersection of the voltage limit curve and the current torque curve in the current coordinate system, the target operating current of the drive motor is determined; the voltage corresponding to the target operating current is determined as the target operating voltage

[0022] In some embodiments of the present application, based on the above technical solution, the voltage determination module is specifically configured as follows: in the current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor, according to the intersection of the current limit curve and the current torque curve in the current coordinate system, the target operating current of the drive motor is determined; the voltage corresponding to the target operating current is determined as the target operating voltage

[0023] According to one aspect of an embodiment of the present application, an electronic device is provided, comprising: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to execute a motor control method as in the above technical solution by executing the executable instructions.

[0024] According to one aspect of an embodiment of the present application, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the motor control method in the above technical solution is implemented.

[0025] In the embodiments of the present application, the operating voltage of the drive motor is increased by step-up and transformation of the drive motor, thereby widening the range of the heat generated by the drive motor, thereby improving the heat generation capacity of the drive motor and avoiding insufficient heat generation in a low temperature environment and resulting in reduced heating effect, which is beneficial to ensuring the operating temperature of the power battery and improving the vehicle's user experience.

[0026] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] In the attached picture:

[0029] Figure 1 The system architecture of a motor control solution applied to a drive motor system according to an embodiment of the present application.

[0030] Figure 2 A schematic diagram of the energy flow relationship in this architecture is shown in FIG.

[0031] Figure 3 A flow chart of a motor control method according to an embodiment of the present application is shown.

[0032] Figure 4 Schematic diagram of the current curve before voltage boost in the embodiment of the present application.

[0033] Figure 5 Schematic diagram of the current curve after voltage boost in the embodiment of the present application.

[0034] Figure 6 The block diagram schematically shows the composition of the motor control device in the embodiment of the present application.

[0035] Figure 7 A schematic diagram of the structure of a computer system suitable for implementing an electronic device of an embodiment of the present application is shown. DETAILED DESCRIPTION

[0036] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more comprehensive and complete and fully convey the concept of the example embodiments to those skilled in the art.

[0037] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0038] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0039] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0040] It should be understood that the solution of this application can be applied to the field of thermal management of new energy vehicles, and specifically to the development of electric drive self-heating control strategies. Electric drive self-heating refers to a function that controls the drive motor to generate more heat during parking and driving, which is used to increase the heat generation of the electric drive at low temperatures, and connect the thermal management water circuit in series with the electric drive water circuit, and recover the heat energy generated by the drive motor through the thermal management integrated module, which can be used to heat the battery pack or the passenger compartment.

[0041] The decline in working performance of batteries of new energy vehicles in low temperature environments has always been a difficulty faced by the new energy vehicle field. Therefore, how to maintain the temperature of the power battery of new energy vehicles in low temperature environments has become an important problem to be solved. In related technologies, the thermal management water circuit is connected in series with the water circuit of the drive motor, and the heat energy generated by the drive motor during parking and driving is recovered through the thermal management integrated module, thereby heating the power battery or the passenger compartment. However, in such solutions, the heating capacity of the drive motor is limited. In low temperature environments, insufficient heat generation may occur, resulting in reduced heating effect, so that the battery cannot be heated to the predetermined temperature and performance is reduced, affecting the vehicle's user experience.

[0042] Based on this, the technical solution of the embodiment of the present application proposes a motor control solution. In this solution, when the vehicle needs to heat the battery in a low-temperature environment, the boost circuit is controlled to output a corresponding voltage, and the working voltage of the motor is increased through boost control, so that the vehicle can select a larger working current as needed, and further reduce the motor efficiency to improve the motor's heating capacity, thereby widening the power range of electric drive heating. In general, the present application first obtains the wheel-end required torque by looking up the table based on the current vehicle speed and accelerator pedal opening, and then determines whether there is a heating demand. If there is no heating demand, the dual-motor high-efficiency drive mode or the sports mode is selected according to the driver's operation; otherwise, the electric drive heating mode is selected, and the current motor's operating point is selected according to the heat generation, and the boost circuit is controlled to output the corresponding voltage. Please refer to Figure 1According to the system architecture of the motor control solution applied to the drive motor system of the embodiment of the present application, the overall system architecture may include two drive motors and a corresponding motor controller Inv, a transformer, and a power battery Battery. The two drive motors respectively drive corresponding tires to drive the vehicle under the power supply of the power battery. Figure 2 A schematic diagram of the energy flow relationship in this architecture is shown in FIG. Figure 2 As shown, the battery supplies energy to two motor controllers Inv through a step-up and voltage conversion circuit, and the motor controllers drive corresponding drive motors respectively, and the drive motors drive the wheels through a transmission device.

[0043] The following is a detailed description of the implementation details of the technical solution of the embodiment of the present application: Figure 3 , Figure 3 A flow chart of a motor control method according to an embodiment of the present application is shown. The motor control method can be specifically executed by a vehicle control system, for example, by a computer, a vehicle terminal or a controller where the vehicle control system is located. Figure 1 As shown, the motor control method at least includes steps S310 to S360, which are described in detail as follows:

[0044] Step S310, obtaining an initial voltage and a target heating value of a driving motor of the vehicle and determining a working torque of the driving motor, wherein the initial voltage is lower than or equal to a voltage of a power battery of the vehicle.

[0045] In this embodiment, the vehicle is in a started state, which can be a parking state or a driving state. The initial voltage of the drive motor is the current voltage of the drive motor when the scheme is executed. The target heating value is the heating value to be achieved by the drive motor determined by the control system of the vehicle. The target heating value can be determined based on the current ambient temperature and the demand for heating value. For example, the required heating value is determined as the target heating value based on the current ambient temperature, the target temperature to be achieved, and data such as thermal conductivity and heating rate. The working torque of the drive motor refers to the torque required by the drive motor in the current or target working state, which is affected by factors such as vehicle speed and transmission efficiency. In this application, in the process of controlling the heating value of the motor, the working torque is generally considered to be constant or approximately constant. The initial voltage of the drive motor is lower than or equal to the voltage of the power battery of the vehicle. The voltage of the power battery is the maximum voltage that the power battery itself can output.

[0046] In some optional embodiments of the present application, in the process of determining the working torque of the drive motor, the vehicle will obtain the wheel-end required torque of the vehicle, and then determine the working torque of the drive motor according to the wheel-end required torque and the transmission efficiency of the vehicle. Specifically, in the process of obtaining the wheel-end required torque of the vehicle, the vehicle will first obtain the current vehicle speed and accelerator pedal opening of the vehicle, and then obtain the wheel-end required torque corresponding to the current vehicle speed and the accelerator pedal opening according to the pedal characteristic mapping, and the pedal characteristic mapping is used to represent the mapping relationship between the torque of the drive motor and the accelerator pedal opening.

[0047] Step S320, if the target heating value is higher than the heating value threshold, the boost voltage of the drive motor is determined according to the working torque of the drive motor, the vehicle speed and the boost voltage relationship table, wherein the boost voltage is higher than the voltage of the power battery, and the boost voltage relationship table contains the correspondence between the vehicle speed and the motor torque and the boost voltage.

[0048] Specifically, the heat generation threshold is the heat generation that can be achieved by the drive motor under the maximum current that can be achieved when the power battery outputs the maximum voltage to the drive motor. If the target heat generation is higher than the heat generation threshold, it means that even the maximum output capacity of the power battery cannot meet the current vehicle's demand for heat generation, and the vehicle needs to continue to boost the voltage of the drive motor to allow the drive motor to operate at a higher current. The voltage after boosting becomes a boost voltage, which is higher than the voltage of the power battery. The boost voltage relationship table contains the correspondence between the vehicle speed and motor torque and the boost voltage. The relationship table is usually pre-determined and configured in the vehicle. The vehicle can directly obtain the table when needed, and obtain the corresponding boost voltage by looking up the table according to the vehicle speed and working torque.

[0049] Step S330, determining a target operating voltage according to the boost voltage of the drive motor and the target heating value.

[0050] Specifically, based on the step-up voltage and the target heating value, the operating voltage required for the motor to reach the target heating value can be determined. The operating voltage is usually less than or equal to the step-up voltage, and the operating voltage is usually also subject to the maximum operating current of the drive motor. Based on such constraint information, the vehicle can determine the voltage required for actual operation. The determination process can provide a pre-configured function calculation or directly determine through a corresponding relationship pre-stored on the vehicle.

[0051] In some embodiments, in the process of determining the target working voltage according to the boost voltage of the drive motor and the target heat generation, the vehicle can determine the quadrature axis current and the direct axis current under the boost voltage according to the boost voltage and the motor speed of the drive motor, and then determine the target working voltage according to the current torque curve and the mapping relationship between the quadrature axis current and the direct axis current under the boost voltage, wherein the current torque curve is used to indicate the mapping relationship between the quadrature axis current and the direct axis current of the drive motor at the working torque. In this embodiment, the working torque is considered to be constant, and therefore, the current torque curve is a constant torque curve, and its curve data is mainly related to data such as the inductance parameters of the motor itself.

[0052] In some embodiments, in the process of determining the target operating voltage based on the boost voltage of the drive motor and the target heating value, the vehicle determines the current torque curve of the drive motor based on the working torque of the drive motor, and the current torque curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current of the drive motor at the working torque; then, the voltage limit curve of the vehicle is determined based on the boost voltage and the motor speed of the drive motor, and the voltage limit curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current under the boost voltage; and then the target operating voltage is determined based on the voltage limit curve and the current torque curve of the drive motor.

[0053] The voltage limit curve is used to represent the mapping relationship between the quadrature axis current and the direct axis current under the step-up voltage. For this curve, when the step-up voltage remains unchanged, the higher the motor speed, the smaller the selectable range of the quadrature axis current and the direct axis current. Taking the elliptical voltage limit curve as an example, when the step-up voltage remains unchanged, the higher the motor speed, the smaller the elliptical area of ​​the voltage limit curve. The motor speed of a vehicle can usually be determined based on parameters such as the vehicle speed and tire radius.

[0054] The intersection of the voltage limit curve and the current torque curve can be considered as the optional range of the working current of the drive motor. Within this range, the determined current operating point can determine the working voltage accordingly. The magnitude of the working current can determine the heat generated by the drive motor. Therefore, according to the target heat generated, the corresponding current operating point can be determined in the intersection of the voltage limit curve and the current torque curve, and then the corresponding target working voltage can be determined according to the current operating point.

[0055] In an optional embodiment of the present application, the voltage limit curve is an elliptical curve, and the above step of determining the target operating voltage according to the voltage limit curve and the current torque curve of the drive motor includes:

[0056] Determining a current limit curve of the vehicle according to the maximum allowable current of the drive motor, wherein the current limit curve is a circular curve and is used to represent a mapping relationship between a quadrature-axis current and a direct-axis current of the drive motor at the maximum allowable current;

[0057] If the voltage limit curve and the current limit curve are in an intersecting relationship, the target operating voltage is determined according to the current limit curve and the current torque curve of the drive motor.

[0058] The current limit curve is a current curve under the constraint of the maximum allowable current that the drive motor can reach. It is a circular curve and is used to represent the mapping relationship between the quadrature axis current and the direct axis current of the drive motor at the maximum allowable current. When the voltage limit curve and the current limit curve are mapped to the coordinate system established according to the quadrature axis current and the direct axis current, there are usually two relationships between the two, namely, an intersection relationship and an inclusion relationship. Usually, without boosting, the current limit curve contains the voltage limit curve. Therefore, the selection of the working current is mainly constrained by the voltage limit curve, that is, it can only be selected within the voltage limit ellipse. After boosting, the elliptical area of ​​the voltage limit curve increases as the voltage increases, and it will intersect with the current limit curve. At this time, the current maximum value of the voltage limit curve will exceed the maximum allowable current that the drive motor can reach, and the working current will be constrained by the current limit curve. Therefore, the vehicle will determine the target working voltage based on the current limit curve and the current torque curve of the drive motor. The determination method is similar to the process of determining the target working voltage based on the voltage limit curve and the current torque curve.

[0059] In some optional embodiments of the present application, if the current limit curve contains a voltage limit curve, it means that although the drive motor is boosted, and the constraint of the boosted voltage on the current optional range is greater than the constraint range of the maximum output voltage of the power battery on the current, it is still less than the constraint range of the maximum allowable current. Therefore, in the current coordinate system of the quadrature axis current and the direct axis current of the drive motor, the vehicle still determines the target working current of the drive motor according to the intersection of the voltage limit curve and the current torque curve in the current coordinate system, and determines the voltage corresponding to the target working current as the target working voltage. However, it should be noted that the current value range of the boosted voltage limit curve is greater than the current value range of the voltage limit curve of the maximum output voltage of the power battery. The area of ​​the boosted voltage limit ellipse will be greater than the area of ​​the voltage limit ellipse of the maximum output voltage of the power battery. For the current value within the exceeded area range, the heat generation of the drive motor can also be further increased compared to the heat generation of the maximum output voltage of the power battery, thereby obtaining a higher heat generation and heating effect.

[0060] In some optional embodiments, in the process of determining the target operating voltage according to the current limit curve and the current torque curve of the drive motor, the vehicle will determine the target operating current of the drive motor in the current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor according to the intersection of the current limit curve and the current torque curve in the current coordinate system, and then determine the voltage corresponding to the target operating current as the target operating voltage. Specifically, the intersection of the current limit curve and the current torque curve in the current coordinate system is usually the maximum current that can be selected under the current torque, thereby obtaining the maximum current that can be achieved under the current working torque.

[0061] Step S340: outputting the target operating voltage to the drive motor.

[0062] The output end of the power battery is connected to a step-up and transformation device, such as a transformer. The vehicle controls the transformer to increase the voltage outputted by the power point to a target operating voltage and then outputs it to the drive motor, so that the current of the drive motor can reach the current required for the target heat generation.

[0063] In the embodiments of the present application, the operating voltage of the drive motor is increased by step-up and transformation of the drive motor, thereby widening the range of the heat generated by the drive motor, thereby improving the heat generation capacity of the drive motor and avoiding insufficient heat generation in a low temperature environment and resulting in reduced heating effect, which is beneficial to ensuring the operating temperature of the power battery and improving the vehicle's user experience.

[0064] In the embodiments of the present application, the operating voltage of the drive motor is increased by step-up and transformation of the drive motor, thereby widening the range of the heat generated by the drive motor, thereby improving the heat generation capacity of the drive motor and avoiding insufficient heat generation in a low temperature environment and resulting in reduced heating effect, which is beneficial to ensuring the operating temperature of the power battery and improving the vehicle's user experience.

[0065] The scheme of the present application is introduced below in conjunction with a specific embodiment. In the scheme of the present application, the vehicle determines the operating voltage through the following steps: Step 1: According to the accelerator pedal opening and the actual vehicle speed, query the pre-stored table to obtain the driver's wheel end required torque; Step 2: According to the current temperature, determine the heat generation of the current motor required for thermal management; Step 3: According to the heat generation, choose whether to boost the voltage, and calculate the working current point of the motor after boosting; Step 4: Based on the calculation result, select the current working point, and control the transformer to output the corresponding voltage.

[0066] Specifically, when the motor is running, the motor controller controls the electric power input of the motor, converting the electric energy into mechanical energy to drive the transmission system. The motor will generate heat in the above process, among which the copper loss varies quadratically with the stator current. The ohmic loss formula is given by the following formula: W c =mI 2 Rc , where m is the number of phases of the permanent magnet synchronous motor; I is the effective value of the coil current, in A; R c is the resistance value of each phase winding, in Ω. The vehicle will then determine whether there is a heating demand at the current power management. If there is no heating demand, it will select the dual-motor high-efficiency driving mode or sports mode according to the driver's needs; otherwise, it will select the electric drive heating mode. In the electric drive heating mode, the first step is to obtain the wheel end torque requirement T DrvReq , the vehicle speed is V Spd , the tire radius is r. Assume that the transmission efficiency of the vehicle is η Trans , the transmission ratio is i Motor , then the total required torque of the motor is Torque required for a single motor Motor speed The constant torque curve T of the motor Motor =P×[ψ f ×I q +(L d -L q )×I q ×I d ], where I d ,I q are the d-axis and q-axis currents, I max It is the maximum allowable current of the electric control. d , L q are the d-axis and q-axis inductances, ψ f is the permanent magnet flux linkage, and P is the number of pole pairs in the permanent magnet synchronous motor. The constant torque curve of the motor is as follows: Figure 4 As shown, in the high efficiency mode, the current at the high efficiency point will be selected, i.e. is the minimum, that is Figure 4 Step 2: When there is a need for heating at low temperature, the intersection of the voltage limit ellipse and the current limit circle is recorded as the current optional area. Assume that the motor is a built-in permanent magnet synchronous motor and the battery pack voltage is U dc , before boosting, the current and voltage constraint equations are:

[0067] Current limit circle:

[0068] Voltage limit ellipse:

[0069] Before boosting, at a certain speed, the maximum current that can be selected is Figure 4 Selectable inefficiency points in . Figure 4 It can be seen that the current is constrained by the voltage limit ellipse.

[0070] Step 3: When the heat generation is insufficient, the area of ​​the voltage limit ellipse is increased by boosting the voltage. Assume that the battery pack voltage after boosting is U dc_up, then the voltage limit ellipse after boost is as follows:

[0071] Voltage limit ellipse (after boost):

[0072] This method can increase the effective current of the motor and increase the heat generation. The maximum current that can be selected is Figure 5 The selectable inefficient point in the figure shows that the current after boosting is not constrained by the voltage limit ellipse but by the current limit circle. The maximum current is larger than that before boosting, so the heat generated by the motor will increase.

[0073] Finally, in actual applications, the actual vehicle can calibrate the boost point according to the specific vehicle speed, torque and heat generation to improve the speed of heating response. For example, the calibration table can be as follows:

[0074] 1000-3000 3000-5000 5000-7000 7000-9000 9000-11000 10-30 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> 30-50 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> 50-70 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> 70-90 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> 90-110 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> 110-130 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> 130-150 <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]> <![CDATA[U dc_up ]]>

[0075] It should be noted that although the steps of the method in the present application are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0076] The following introduces the device implementation of the present application, which can be used to execute the motor control method in the above embodiments of the present application. Figure 6 The block diagram of the motor control device in the embodiment of the present application is schematically shown. Figure 6 As shown, the motor control device 600 may mainly include:

[0077] A data acquisition module 610 is configured to acquire an initial voltage and a target heat value of a driving motor of a vehicle and determine a working torque of the driving motor, wherein the initial voltage is lower than or equal to a voltage of a power battery of the vehicle;

[0078] The boost module 620 is configured to determine the boost voltage of the drive motor according to the working torque of the drive motor, the vehicle speed and a boost voltage relationship table if the target heat value is higher than the heat value threshold, wherein the boost voltage is higher than the voltage of the power battery, and the boost voltage relationship table includes a correspondence between the vehicle speed and the motor torque and the boost voltage;

[0079] A voltage determination module 630 is configured to determine a target operating voltage according to the boost voltage of the drive motor and the target heat generation;

[0080] The voltage output module 640 is configured to output the target operating voltage to the driving motor.

[0081] In some embodiments of the present application, based on the above technical solution, the voltage determination module 630 is specifically configured to: determine the quadrature-axis current and the direct-axis current under the boost voltage according to the boost voltage and the motor speed of the drive motor; determine the target operating voltage according to the current torque curve and the mapping relationship between the quadrature-axis current and the direct-axis current under the boost voltage, and the current torque curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current of the drive motor at the operating torque.

[0082] In some embodiments of the present application, based on the above technical solution, the data acquisition module 610 is specifically configured to: obtain the current vehicle speed and accelerator pedal opening of the vehicle; obtain the wheel-end required torque corresponding to the current vehicle speed and the accelerator pedal opening according to the pedal characteristic mapping, and the pedal characteristic mapping is used to represent the mapping relationship between the wheel-end required torque and the accelerator pedal opening; determine the working torque of the drive motor according to the wheel-end required torque and the transmission efficiency of the vehicle.

[0083] In some embodiments of the present application, based on the above technical solution, the voltage determination module 630 is specifically configured to: determine the current torque curve of the drive motor according to the working torque of the drive motor, and the current torque curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current of the drive motor at the working torque; determine the voltage limit curve of the vehicle according to the boost voltage and the motor speed of the drive motor, and the voltage limit curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current under the boost voltage; determine the target working voltage according to the voltage limit curve and the current torque curve of the drive motor.

[0084] In some embodiments of the present application, based on the above technical solution, the voltage limit curve is an elliptical curve, and the voltage determination module 630 is specifically configured to: determine the current limit curve of the vehicle according to the maximum allowable current of the drive motor, wherein the current limit curve is a circular curve and is used to represent the mapping relationship between the cross-axis current and the direct-axis current of the drive motor at the maximum allowable current; if the voltage limit curve and the current limit curve are in an intersecting relationship, then determine the target operating voltage according to the current limit curve and the current torque curve of the drive motor.

[0085] In some embodiments of the present application, based on the above technical solution, the voltage determination module 630 is further configured as follows: if the current limit curve contains the voltage limit curve, then in the current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor, according to the intersection of the voltage limit curve and the current torque curve in the current coordinate system, the target operating current of the drive motor is determined; the voltage corresponding to the target operating current is determined as the target operating voltage

[0086] In some embodiments of the present application, based on the above technical solution, the voltage determination module 630 is specifically configured as: in the current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor, according to the intersection of the current limit curve and the current torque curve in the current coordinate system, the target operating current of the drive motor is determined; and the voltage corresponding to the target operating current is determined as the target operating voltage.

[0087] It should be noted that the device provided in the above embodiment and the method provided in the above embodiment belong to the same concept, wherein the specific manner in which each module performs the operation has been described in detail in the method embodiment and will not be repeated here.

[0088] Figure 7 A schematic diagram of the structure of a computer system suitable for implementing an electronic device of an embodiment of the present application is shown.

[0089] It should be noted that Figure 7 The computer system 700 of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0090] like Figure 7 As shown, the computer system 700 includes a central processing unit (CPU) 701, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 702 or the program loaded from the storage part 708 to the random access memory (RAM) 703. In the RAM 703, various programs and data required for system operation are also stored. The CPU 701, the ROM 702 and the RAM 703 are connected to each other through a bus 704. An input / output (I / O) interface 705 is also connected to the bus 704.

[0091] The following components are connected to the I / O interface 705: an input section 706 including a keyboard, a mouse, etc.; an output section 707 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 708 including a hard disk, etc.; and a communication section 709 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to the I / O interface 705 as needed. A removable medium 711, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 710 as needed so that a computer program read therefrom is installed into the storage section 708 as needed.

[0092] In particular, according to an embodiment of the present application, the process described in each method flow chart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer readable medium, and the computer program includes a program code for executing the method shown in the flow chart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication part 709, and / or installed from a removable medium 711. When the computer program is executed by a central processing unit (CPU) 701, various functions defined in the system of the present application are executed.

[0093] It should be noted that the computer-readable medium shown in the embodiment of the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium may be, for example, - but not limited to - an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by an instruction execution system, device or device or used in combination with it. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, wherein a computer-readable program code is carried. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, which may send, propagate, or transmit programs for use by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0094] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the above-mentioned module, program segment or a part of a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flow chart, and the combination of the boxes in the block diagram or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0095] It should be noted that, although several modules or units of the equipment for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into being embodied by multiple modules or units.

[0096] Through the description of the above implementation methods, it is easy for those skilled in the art to understand that the example implementation methods described here can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution according to the implementation methods of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, a server, a touch terminal, or a network device, etc.) to execute the method according to the implementation methods of the present application.

[0097] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary technical means in the art that are not disclosed in the present application.

[0098] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A motor control method, characterized in that: include: Obtaining an initial voltage and a target heat value of a driving motor of the vehicle and determining a working torque of the driving motor, wherein the initial voltage is lower than or equal to a voltage of a power battery of the vehicle; If the target heating value is higher than the heating value threshold, the boost voltage of the drive motor is determined according to the working torque of the drive motor, the vehicle speed, and a boost voltage relationship table, wherein the boost voltage is higher than the voltage of the power battery, and the boost voltage relationship table includes a correspondence between the vehicle speed, the motor torque, and the boost voltage; Determining a target operating voltage according to the boost voltage of the drive motor and the target heating value; The target operating voltage is output to the driving motor.

2. The motor control method according to claim 1, characterized in that: The step of determining the target operating voltage according to the boost voltage of the drive motor and the target heating value includes: Determining a quadrature-axis current and a direct-axis current under the boosted voltage according to the boosted voltage and the motor speed of the drive motor; The target operating voltage is determined according to the current torque curve and the mapping relationship between the quadrature-axis current and the direct-axis current under the stepped-up voltage. The current torque curve is used to indicate the mapping relationship between the quadrature-axis current and the direct-axis current of the drive motor at the operating torque.

3. The method according to claim 1, characterized in that The determining the working torque of the driving motor comprises: Obtaining the current speed and accelerator pedal opening of the vehicle; Obtaining the wheel end required torque corresponding to the current vehicle speed and the accelerator pedal opening according to a pedal characteristic map, wherein the pedal characteristic map is used to represent a mapping relationship between the wheel end required torque and the accelerator pedal opening; The working torque of the driving motor is determined according to the wheel end required torque and the transmission efficiency of the vehicle.

4. The method according to claim 1, characterized in that: The step of determining the target operating voltage according to the boost voltage of the drive motor and the target heating value includes: Determining a current torque curve of the drive motor according to the working torque of the drive motor, wherein the current torque curve is used to indicate a mapping relationship between a quadrature-axis current and a direct-axis current of the drive motor at the working torque; Determining a voltage limit curve of the vehicle according to the boost voltage and the motor speed of the drive motor, wherein the voltage limit curve is used to represent a mapping relationship between a quadrature-axis current and a direct-axis current under the boost voltage; A target operating voltage is determined according to the voltage limit curve and the current torque curve of the drive motor.

5. The method according to claim 4, characterized in that The voltage limit curve is an elliptical curve, and determining the target operating voltage according to the voltage limit curve and the current torque curve of the drive motor includes: Determining a current limit curve of the vehicle according to the maximum allowable current of the drive motor, wherein the current limit curve is a circular curve and is used to represent a mapping relationship between a quadrature-axis current and a direct-axis current of the drive motor at the maximum allowable current; If the voltage limit curve and the current limit curve are in an intersecting relationship, the target operating voltage is determined according to the current limit curve and the current torque curve of the drive motor.

6. The method according to claim 5, characterized in that The method further comprises: If the current limit curve includes the voltage limit curve, then in the current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor, the target operating current of the drive motor is determined according to the intersection of the voltage limit curve and the current torque curve in the current coordinate system; The voltage corresponding to the target operating current is determined as the target operating voltage.

7. The method according to claim 5, characterized in that The step of determining a target operating voltage according to the current limit curve and the current torque curve of the drive motor comprises: In a current coordinate system of the quadrature-axis current and the direct-axis current of the drive motor, determining a target operating current of the drive motor according to an intersection point of the current limit curve and the current torque curve in the current coordinate system; The voltage corresponding to the target operating current is determined as the target operating voltage.

8. A motor control device, characterized in that: include: A data acquisition module, configured to acquire an initial voltage and a target heating value of a driving motor of the vehicle and determine a working torque of the driving motor, wherein the initial voltage is lower than or equal to a voltage of a power battery of the vehicle; a boost module, configured to determine a boost voltage of the drive motor according to the working torque of the drive motor, the speed of the vehicle, and a boost voltage relationship table if the target heat value is higher than a heat value threshold, wherein the boost voltage is higher than the voltage of the power battery, and the boost voltage relationship table includes a correspondence between the vehicle speed and the motor torque and the boost voltage; A voltage determination module, configured to determine a target operating voltage according to the boost voltage of the drive motor and the target heating value; A voltage output module is configured to output the target operating voltage to the drive motor.

9. An electronic device, characterized in that: include: processor; A memory, configured to store executable instructions of the processor; The processor is configured to execute the motor control method according to any one of claims 1 to 7 by executing the executable instructions.

10. A computer readable medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the motor control method according to any one of claims 1 to 7 is implemented.

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