Control method of dual-motor drive system, storage medium and new energy vehicle

Abstract

The application discloses a control method of a double-motor driving system, a storage medium and a new energy vehicle. The double-motor driving system comprises a first motor and a second motor, and the method comprises the following steps: obtaining a target torque of the double-motor driving system, and obtaining a first temperature of the first motor and a second temperature of the second motor; distributing the torque of the first motor and the second motor according to the first temperature, the second temperature and the target torque; obtaining a torque output curve of the first motor and / or the second motor through optimization calculation according to a torque distribution result and an efficiency MAP graph of the first motor and / or the second motor; and controlling the first motor and / or the second motor to output torque according to the torque output curve. The method can improve the operation efficiency of the double-motor system when the working condition changes, and simultaneously avoids the limitation of energy accumulation on the output of the motor.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle technology, and in particular to a control method, storage medium, and new energy vehicle for a dual-motor drive system. Background Technology

[0002] The powertrain systems of new energy vehicles employing dual-motor independent output systems can fully leverage the optimal matching under various road conditions and improve the utilization rate of the motor system's high-efficiency range. In particular, for dual-motor systems using synchronous and asynchronous motors, the advantages of the synchronous motor's low-speed, high-efficiency range distribution and the asynchronous motor's high-speed range distribution can be fully utilized. Energy diversion control can be implemented for different vehicle operating conditions, improving the operating efficiency of the electric drive system and reducing overall vehicle energy consumption.

[0003] Due to their inherent characteristics, the drive motor system of new energy vehicles generates a high amount of energy accumulation during acceleration and deceleration. Frequent acceleration and deceleration can cause the motor temperature to rise too quickly, easily triggering the motor temperature alarm and resulting in power output limitation. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this invention is to provide a control method for a dual-motor drive system, a storage medium, and a new energy vehicle, to avoid energy accumulation limiting the motor output.

[0005] A second objective of this invention is to provide a computer-readable storage medium.

[0006] The third objective of this invention is to propose a new energy vehicle.

[0007] To achieve the above objectives, a first aspect of the present invention provides a control method for a dual-motor drive system, the dual-motor drive system including a first motor and a second motor, the method comprising: acquiring a target torque of the dual-motor drive system, and acquiring a first temperature of the first motor and a second temperature of the second motor; performing torque distribution on the first motor and the second motor according to the first temperature, the second temperature and the target torque; obtaining a torque output curve of the first motor and / or the second motor through optimization calculation based on the torque distribution result and the efficiency MAP of the first motor and / or the second motor; and controlling the first motor and / or the second motor to output torque according to the torque output curve.

[0008] To achieve the above objectives, a second aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described method.

[0009] To achieve the above objectives, a third aspect of the present invention provides a new energy vehicle, comprising: a dual-motor drive system, the dual-motor drive system including a first motor and a second motor; a dual-motor controller, the dual-motor controller being connected to the first motor and the second motor respectively, the dual-motor controller including a memory, a processor and a computer program stored in the memory, wherein when the computer program is executed by the processor, the above-described method is implemented.

[0010] The control method, storage medium, and new energy vehicle of the dual-motor drive system of this invention can acquire the target torque of the dual-motor drive system and the first temperature of the first motor and the second temperature of the second motor. Based on the first and second temperatures, the target torque is allocated to the first and second motors. After allocation, the torque output curves of the first and / or second motors are obtained based on the allocation results and an efficiency MAP table. The motors are then controlled to output torque using these torque output curves. This allows for adjustment of motor output based on motor temperature, thereby reasonably controlling motor temperature, reducing the probability of temperature alarms, and preventing energy accumulation from limiting motor output without reducing the overall output of the dual-motor drive system.

[0011] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0012] Figure 1 This is a flowchart of a control method for a dual-motor drive system according to an embodiment of the present invention;

[0013] Figure 2 This is a structural block diagram of a new energy vehicle according to an embodiment of the present invention. Detailed Implementation

[0014] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0015] The control method, storage medium, and new energy vehicle of the dual-motor drive system according to embodiments of the present invention are described below with reference to the accompanying drawings.

[0016] Figure 1 This is a flowchart of a control method for a dual-motor drive system according to an embodiment of the present invention.

[0017] In this embodiment of the invention, the dual-motor drive system includes a first motor and a second motor.

[0018] like Figure 1 As shown, the control method for the dual-motor drive system includes:

[0019] S11, obtain the target torque of the dual-motor drive system, and obtain the first temperature of the first motor and the second temperature of the second motor.

[0020] Specifically, during vehicle operation, such as acceleration and deceleration, the vehicle controller collects information from the accelerator or brake pedals, current drive system torque, and other data. Based on this information, it analyzes the driver's intentions, calculates the target torque, and sends the result to the dual-motor controller. This target torque is the total output target torque value of the two motors. The dual-motor controller collects information on motor operating status and motor temperature, among other data.

[0021] The aforementioned accelerator pedal or brake pedal information includes the accelerator pedal or brake pedal opening degree; the aforementioned motor operating status information includes the current speed and torque of the first motor and the current speed and torque of the second motor; the aforementioned motor temperature information includes the current first temperature of the first motor and the current second temperature of the second motor.

[0022] S12, based on the first temperature, the second temperature and the target torque, performs torque distribution to the first motor and the second motor.

[0023] Specifically, the dual-motor controller determines whether the first temperature and the second temperature meet the preset temperature balance requirements. If they do, the target torque is allocated to the first motor and the second motor according to the preset program of the dual-motor drive system. If they do not meet the requirements, the difference between the first temperature and the second temperature is calculated, and the torque is allocated to the first motor and the second motor according to the difference and the target torque.

[0024] Specifically, the dual-motor controller can first determine whether both the first and second temperatures are less than a preset temperature threshold. If so, it determines that the first and second temperatures meet the preset temperature balance requirement. The preset temperature threshold is a value set according to actual conditions, for example, 90% of the alarm temperature. If both the first and second temperatures are less than the preset temperature threshold, it indicates that both the first and second motors are currently in normal operation, and the target torque can be allocated to the first and second motors according to the decomposed torque target of the dual-motor drive system. If at least one of the first and second temperatures is greater than or equal to the preset temperature threshold, it indicates that a motor has excessive energy accumulation. In this case, it is necessary to first calculate the difference between the first and second temperatures, and then determine whether the difference exceeds a preset difference threshold. The preferred range of this preset difference threshold is 20–30°C, for example, 25°C. If it exceeds, the target torque is allocated to the motor corresponding to the lower of the first and second temperatures, i.e., the motor in better condition outputs the target torque. If it does not exceed, the target torque is allocated to the first and second motors according to the torque allocation ratio in the preset program.

[0025] S13. Based on the torque distribution results and the efficiency MAP of the first motor and / or the second motor, the torque output curves of the first motor and / or the second motor are obtained through optimization calculation.

[0026] Specifically, if the target torque is allocated to the first motor, the torque output curve of the first motor is obtained based on the efficiency MAP of the first motor; if the target torque is allocated to the second motor, the torque output curve of the second motor is obtained based on the efficiency MAP of the second motor; if the target torque is allocated to both the first and second motors, the torque output curve of the first motor is obtained based on the efficiency MAP of the first motor, and the torque output curve of the second motor is obtained based on the efficiency MAP of the second motor.

[0027] Specifically, for the first motor, the current speed and current torque of the first motor can be obtained, and the allocated torque of the first motor can be obtained; based on the current speed, current torque and allocated torque of the first motor, at least two transformation path curves are obtained on the efficiency MAP of the first motor; based on the at least two transformation path curves, the torque output curve of the first motor is obtained.

[0028] Specifically, an efficiency MAP table for the first motor can be pre-set. This efficiency MAP table can, for example, represent the correspondence between motor speed, motor torque, and efficiency. That is, after obtaining a motor speed and a motor torque, the efficiency corresponding to that motor speed and motor torque can be obtained by looking up the table. Furthermore, after obtaining the current speed, current torque, and allocated torque of the first motor, the current position of the first motor in the first motor efficiency MAP table is determined based on the current speed and current torque. The possible positions of the first motor in the first motor efficiency MAP table are determined based on the allocated torque. From the possible positions, the target position is determined. For example, the allocated torque can be determined first, and then the maximum motor speed that the current torque or allocated torque can support can be determined. Thus, the target position is determined based on the motor speed and allocated torque. For example, if the current vehicle is uphill, the motor speed at the target position will be lower; if the current vehicle is downhill, the motor speed at the target position will be higher. Then, at least two transformation path curves with the starting point being the current position and the ending point being the target position are drawn on a rectangular coordinate system with the horizontal and vertical axes being the motor speed and the motor torque, respectively, according to preset rules. The transformation path curves include linear curves and nonlinear curves, and the efficiency at each point on the transformation path curve can be obtained. The nonlinear curves include at least one of exponential curves and quadratic curves.

[0029] Furthermore, the average efficiency of each transformation path curve is calculated separately; the transformation path curve with the highest average efficiency is taken as the torque output curve of the first motor. This allows full utilization of the motor's high-efficiency range, achieving optimal motor output efficiency.

[0030] Specifically, for the second motor, its current speed and torque can be obtained. Based on the current speed, current torque, and the distributed torque of the second motor, at least two transformation path curves are obtained on the efficiency MAP of the second motor. Based on the at least two transformation path curves, the torque output curve of the second motor is obtained. The specific method is the same as that described above for the first motor, and will not be repeated here.

[0031] S14, according to the torque output curve, control the first motor and / or the second motor to output torque.

[0032] Specifically, after obtaining the torque output curves of the first motor and / or the second motor, the dual-motor controller can control the corresponding motor to output according to the curve until the motor torque reaches the allocated torque.

[0033] In summary, the control method for the dual-motor drive system of this invention can obtain the target torque of the dual-motor drive system, and obtain the first temperature of the first motor and the second temperature of the second motor. Then, based on the first and second temperatures, the target torque is allocated to the first and second motors. After allocation, the torque output curves of the first motor and / or the second motor are obtained based on the allocation results and an efficiency MAP table, and the motors are controlled to output torque using these torque output curves. Therefore, the output of the motors can be adjusted according to their temperatures, thereby reasonably controlling the motor temperatures, reducing the probability of temperature alarms, and avoiding energy accumulation that could limit the motor output without reducing the overall output of the dual-motor drive system. Furthermore, after obtaining the torque allocation results, the conversion path curve with the highest average efficiency corresponding to each motor can be obtained from the efficiency MAP table, thereby improving the efficiency of the dual-motor drive system, reducing overall vehicle energy consumption, and increasing driving range.

[0034] Furthermore, the present invention proposes a computer-readable storage medium.

[0035] In this embodiment of the invention, a computer program is stored on a computer-readable storage medium, which, when executed by a processor, implements the above-described method.

[0036] The computer-readable storage medium of this invention, when a computer program stored thereon is executed by a processor, can acquire the target torque of a dual-motor drive system, acquire the first temperature of the first motor and the second temperature of the second motor, and then allocate the target torque to the first and second motors based on the first and second temperatures. After allocation, the torque output curves of the first and / or second motors are obtained based on the allocation results and an efficiency MAP table, and the motors are controlled to output torque based on these torque output curves. This allows for adjustment of motor output based on motor temperature, thereby reasonably controlling motor temperature, reducing the probability of temperature alarms, and avoiding energy accumulation that could limit motor output without reducing the overall output of the dual-motor drive system. Furthermore, after obtaining the torque allocation results, the conversion path curve with the highest average efficiency corresponding to each motor can be obtained from the efficiency MAP table, thereby improving the efficiency of the dual-motor drive system.

[0037] Furthermore, this invention proposes a new energy vehicle.

[0038] Figure 2 This is a structural block diagram of a new energy vehicle according to an embodiment of the present invention.

[0039] like Figure 2 As shown, the new energy vehicle 100 includes a dual-motor drive system 200 and a dual-motor controller 300.

[0040] Specifically, the dual-motor drive system 200 includes a first motor 201 and a second motor 202; the dual-motor controller 300 is connected to the first motor 201 and the second motor 202 respectively, and the dual-motor controller 300 includes a memory, a processor and a computer program stored in the memory. When the computer program is executed by the processor, it implements the above-described method.

[0041] The new energy vehicle of this invention, by implementing the above method, can obtain the target torque of a dual-motor drive system, and obtain the first temperature of the first motor and the second temperature of the second motor. Then, based on the first and second temperatures, the target torque is allocated to the first and second motors. After allocation, the torque output curves of the first and / or second motors are obtained based on the allocation results and an efficiency MAP table, and the motors are controlled to output torque using these torque output curves. Therefore, the motor output can be adjusted according to the motor temperature, thereby reasonably controlling the motor temperature, reducing the probability of temperature alarms, and avoiding energy accumulation that limits motor output without reducing the overall output of the dual-motor drive system. Furthermore, after obtaining the torque allocation results, the conversion path curve with the highest average efficiency corresponding to each motor can be obtained from the efficiency MAP table, thereby improving the efficiency of the dual-motor drive system.

[0042] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0043] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0044] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0045] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0048] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0049] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A control method for a dual-motor drive system, characterized in that, The dual-motor drive system includes a first motor and a second motor, and the method includes: Obtain the target torque of the dual-motor drive system, and obtain the first temperature of the first motor and the second temperature of the second motor; Based on the first temperature, the second temperature, and the target torque, torque is distributed between the first motor and the second motor; Based on the torque distribution results and the efficiency MAP of the first motor and / or the second motor, the torque output curves of the first motor and / or the second motor are obtained through optimization calculation. According to the torque output curve, control the first motor and / or the second motor to output torque; Based on the torque distribution results and the efficiency MAP of the first motor and / or the second motor, the torque output curves of the first motor and / or the second motor are obtained, including: If the target torque is allocated to the first motor, the torque output curve of the first motor is obtained according to the efficiency MAP of the first motor. If the target torque is allocated to the second motor, the torque output curve of the second motor is obtained according to the efficiency MAP of the second motor. If the target torque is distributed to the first motor and the second motor, then the torque output curve of the first motor is obtained according to the efficiency MAP of the first motor, and the torque output curve of the second motor is obtained according to the efficiency MAP of the second motor. The step of obtaining the torque output curve of the first motor based on the efficiency MAP diagram of the first motor includes: Obtain the current speed and current torque of the first motor, and obtain the allocated torque of the first motor; Based on the current speed, the current torque, and the distributed torque of the first motor, at least two transformation path curves are obtained on the efficiency MAP of the first motor. Based on the at least two transformation path curves, the torque output curve of the first motor is obtained; The step of obtaining the torque output curve of the first motor based on the at least two transformation path curves includes: Calculate the average efficiency for each of the aforementioned transformation path curves; The transformation path curve with the highest average efficiency is used as the torque output curve of the first motor.

2. The control method for the dual-motor drive system as described in claim 1, characterized in that, The step of distributing torque between the first motor and the second motor based on the first temperature, the second temperature, and the target torque includes: Determine whether the first temperature and the second temperature meet the preset temperature balance requirements; If the conditions are met, the target torque is allocated to the first motor and the second motor according to the torque allocation ratio in the preset program of the dual-motor drive system. If the conditions are not met, the difference between the first temperature and the second temperature is calculated, and torque is distributed between the first motor and the second motor based on the difference and the target torque.

3. The control method for the dual-motor drive system as described in claim 2, characterized in that, The step of determining whether the first temperature and the second temperature meet the preset temperature balance requirement includes: Determine whether both the first temperature and the second temperature are less than a preset temperature threshold. If so, it is determined that the first temperature and the second temperature meet the preset temperature balance requirement.

4. The control method for the dual-motor drive system as described in claim 2, characterized in that, The step of distributing torque between the first motor and the second motor based on the difference and the target torque includes: Determine whether the difference exceeds a preset difference threshold; If the target torque is exceeded, the target torque is allocated to the motor corresponding to the smaller of the first temperature and the second temperature. If the target torque is not exceeded, the target torque is allocated to the first motor and the second motor according to the torque allocation ratio in the preset program.

5. The control method for the dual-motor drive system as described in claim 1, characterized in that, The transformation path curve includes linear curves and nonlinear curves, wherein the nonlinear curve includes at least one of exponential curves and quadratic curves.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1-5.

7. A new energy vehicle, characterized in that, include: A dual-motor drive system, comprising a first motor and a second motor; A dual-motor controller, which is connected to the first motor and the second motor respectively, includes a memory, a processor and a computer program stored in the memory, wherein when the computer program is executed by the processor, it implements the method as described in any one of claims 1-5.

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