A torque limiting method, computer equipment, readable storage medium and motor vehicle

Abstract

The present invention discloses a torque limiting method, a computer device, a readable storage medium and a motor vehicle, and relates to the field of automobile technology. A motor controller limits the output torque of a motor through the torque limiting method, and includes the following steps: obtaining the water inlet temperature, the water pump gear position and the battery voltage, and obtaining the initial output current limit value according to the method; obtaining the opening of the accelerator pedal at the current moment, and judging whether it is necessary to limit the current initial output current limit value according to the method, when the opening is greater than or equal to the preset opening, the initial output current limit value is maintained, and when the opening is less than the preset opening, the initial output current limit value is reduced to form a process output current limit value; the current torque limit value is determined according to the motor speed and the initial output current limit value or the process output current limit value. The torque limiting method provided by the present invention can dynamically adjust the output of the torque according to the timely conditions of the whole vehicle.

Description

Technical Field

[0001] The present invention relates to the field of automobile technology, and in particular to a torque limiting method, a computer device, a readable storage medium and a motor vehicle. Background Art

[0002] With the implementation of the national dual-carbon strategy, the emission policy of motor vehicles has become increasingly tightened. In addition, with the national policy supporting new energy vehicles, more and more automakers have launched hybrid electric vehicles, plug-in hybrid electric vehicles, extended-range electric vehicles and pure electric vehicles. These vehicles are equipped with motors, battery packs that provide energy for the motors, and motor controllers that control the motors.

[0003] The vehicle controller (VCU) collects the position signal of the accelerator pedal operated by the driver, analyzes it, and issues a torque command to the motor controller (MCU). The battery pack provides DC power to the motor controller, and the output voltage changes with the battery voltage and the remaining power SOC. After receiving the torque command, the motor controller controls the output of the three-phase current to the drive motor, thereby controlling the output torque value of the drive motor. However, the fixed controller output current limit is used, and the peak output of the motor controller is not dynamically adjusted according to the timely conditions of the vehicle. Under certain extreme conditions, the motor poses a threat to the safety of the controller power module. Summary of the invention

[0004] In order to solve the above-mentioned problems, the present invention provides a torque limiting method, which dynamically adjusts the torque output according to the timely conditions of the whole vehicle.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A torque limiting method, wherein a motor controller limits the output torque of a motor through the torque limiting method, comprises the following steps:

[0007] Initial setting: Get the water inlet temperature of the coolant flow channel at the motor controller, the coolant pump gear and the battery voltage at the current moment, and get the current initial output current limit value according to the water inlet temperature, the water pump gear and the battery voltage;

[0008] Determination: obtaining the opening of the accelerator pedal at the current moment, judging whether the current initial output current limit needs to be limited according to the opening of the accelerator pedal; when the opening of the accelerator pedal is greater than or equal to the preset opening, the current initial output current limit is adopted; when the opening of the accelerator pedal is less than the preset opening, the current initial output current limit is reduced to form a process output current limit;

[0009] Limitation: The current torque limit is determined based on the current motor speed and the initial output current limit or process output current limit.

[0010] The technical solution provided by the present invention can determine the available maximum output peak current under current conditions, and dynamically limit the current peak output by the motor controller to control the torque output by the motor. The capability of the motor controller is maximized under the premise of meeting system safety and reliability. At the same time, the accelerator pedal is used as a driver's intention judgment. When there is no strong power performance requirement, the current of the motor controller is again limited to a certain extent to ensure hardware safety.

[0011] Optionally, in the initial determination step, the water inlet temperature, the water pump gear, and the battery voltage are respectively provided with gear boundary values, and the gear boundary values ​​are provided with a first hysteresis coefficient.

[0012] Optionally, in the determination step, the preset opening is provided with a second hysteresis coefficient.

[0013] The hysteresis coefficient is used to prevent the motor controller from fluctuating when the aforementioned physical quantities change.

[0014] Optionally, after determining the current torque limit, the driver's required torque is determined according to the current motor speed and the opening of the accelerator pedal at the current moment, and the coolant pump gear is adjusted according to the required torque.

[0015] Optionally, the driver's required torque is the product of the opening of the accelerator pedal and the maximum torque limit, and the maximum torque limit is obtained by the speed of the motor.

[0016] Optionally, adjusting the gear position of the coolant pump according to the required torque includes:

[0017] If the required torque is greater than or equal to the current torque limit, the gear of the coolant water pump is increased by one gear, otherwise the gear of the coolant water pump is maintained.

[0018] Through adjustment, the current vehicle condition can be judged in a timely manner, and the coolant pump gear can be adjusted according to the vehicle condition, so that the cooling level is more matched with the current heat dissipation, while also improving the torque limiting effect.

[0019] Optionally, if the coolant water pump gear is raised by one gear, the initialization step, the determination step and the limiting step are re-executed according to the adjusted water pump gear.

[0020] After adjusting the coolant water pump gear, since the water pump gear has changed, the initial output current limit is readjusted according to the changed gear, so that the limit is more accurate and the whole adjustment method forms a closed loop.

[0021] In addition, the present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor implements any of the torque limiting methods described above when executing the computer program.

[0022] At the same time, the present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, any of the torque limiting methods described above is implemented.

[0023] Furthermore, the present invention also provides a motor vehicle having a motor and a motor controller, wherein the motor controller controls the motor by the torque limiting method described in any one of the preceding claims.

[0024] or the motor vehicle has the aforementioned computer device;

[0025] Or the motor vehicle has the aforementioned computer-readable storage medium, and when the computer program is executed by a processor, any of the aforementioned torque limiting methods is implemented.

[0026] These features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. The best embodiments or means of the present invention will be described in detail in conjunction with the drawings, but they are not intended to limit the technical solutions of the present invention. In addition, there are multiple features, elements, and components that appear in each of the following texts and drawings, and different symbols or numbers are marked for convenience, but they all represent components with the same or similar structures or functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below in conjunction with the accompanying drawings:

[0028] Figure 1 It is a schematic diagram of a flow chart in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The technical solutions of the embodiments of the present invention are explained and described below in conjunction with the drawings of the embodiments of the present invention, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

[0030] References in this specification to "one embodiment" or "an example" or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment itself may be included in at least one embodiment of the present patent disclosure. The appearance of the phrase "in one embodiment" in various places in the specification does not necessarily refer to the same embodiment.

[0031] Example:

[0032] like Figure 1As shown, this embodiment provides a torque limiting method. The torque limiting method provided in this embodiment is used for hybrid electric vehicles, plug-in hybrid electric vehicles, extended-range power vehicles and pure electric vehicles. The above types of vehicles are equipped with a motor, a battery pack to provide energy for the motor, and a motor controller to control the motor. At the same time, it is also equipped with a water pump and a cooling water channel for dissipating heat for the battery, motor and motor controller. The motor controller limits the output torque of the motor through the torque limiting method provided in this embodiment, including the following steps:

[0033] Initial determination: Obtain the water inlet temperature of the coolant flow channel at the motor controller, the coolant water pump gear and the battery voltage at the current moment, and obtain the current initial output current limit according to the water inlet temperature, water pump gear and battery voltage. In this step, the water inlet temperature, water pump gear and battery voltage are respectively provided with gear boundary values. After obtaining the water inlet temperature, the coolant water pump gear and the battery voltage, determine the gear interval in which each physical quantity is currently located according to each gear boundary value, and determine the initial output current limit by looking up the table. Specifically in this embodiment, the relationship between the water inlet temperature, water pump gear and battery voltage and their respective gear boundary values ​​and the initial output current limit is as follows:

[0034]

[0035] For example, if the current water inlet temperature is 45°C, the water pump gear is L3, that is, the coolant flow rate is 12L / min, and the battery voltage is 350V, then the initial output current limit is 590A.

[0036] It should be noted that the vehicle model targeted by this implementation is a compact vehicle, including a compact sedan and a compact SUV. When facing other different vehicle models such as mid-sized vehicles, medium and large vehicles, the initial output current limit value can be adaptively adjusted by technical personnel in this field according to the actual vehicle model during debugging and calibration. The adjustment method can adopt the current capacity bench calibration method of the comprehensive electric and thermal coupling working condition module, which is a prior art known in the art and is not limited here. Those skilled in the art should know that the initial output current limit value in the table is only a preferred method specific to this embodiment, and is not a limitation of the technical solution.

[0037] Through the initial steps, the motor controller's capabilities are maximized while meeting the system's safety and reliability requirements. When the vehicle's conditions are relatively friendly, that is, when the water temperature is low, the flow rate is large, and the voltage is low, a larger current can be output to give full play to the hardware characteristics. When the vehicle's conditions are relatively harsh, that is, when the water temperature is high, the flow rate is small, and the voltage is high, the output current is limited to ensure hardware safety and reliability.

[0038] At the same time, a first hysteresis coefficient is set for each gear demarcation value. When the vehicle is running, the water inlet temperature, the water pump gear and the battery voltage will jump into the next gear after rising and reaching the corresponding gear demarcation value. Each physical quantity is changing in real time, so the water inlet temperature, the water pump gear and the battery voltage may all drop. Once it drops to the gear demarcation value, it will jump back to the previous gear. If the physical quantity fluctuates near the gear demarcation value, it will jump between gears. This will cause the initial output current limit output by the motor controller to fluctuate. In this embodiment, the first hysteresis coefficient is set for the water inlet temperature, the water pump gear and the battery voltage. The first hysteresis coefficient makes the difference between the gear demarcation values ​​reached when rising and when falling. The actual value of the gear demarcation value reached when falling is less than the actual value of the gear demarcation value reached when rising, so that it can jump back to the previous gear. This can avoid gear jumping caused by fluctuations in the physical quantity near the gear boundary value, thereby keeping the initial output current limit output by the motor controller stable and preventing fluctuations.

[0039] Determination: Get the opening of the accelerator pedal at the current moment, and determine whether the current initial output current limit needs to be limited according to the opening of the accelerator pedal. When the opening of the accelerator pedal is greater than or equal to the preset opening, the current initial output current limit is used. When the opening of the accelerator pedal is less than the preset opening, the current initial output current limit is reduced to form a process output current limit. The opening of the accelerator pedal is used as a judgment of the driver's intention. When non-strong power performance is required, the current output of the motor controller is further restricted to ensure hardware safety. Specifically in this embodiment, the preset opening is 80% of the maximum opening of the accelerator pedal. In other embodiments, the preset opening can be flexibly set by technicians in this field during calibration and adjustment, and is not limited here. When the accelerator pedal opening is less than 80%, the initial output current limit is reduced from 590Arms to 540Arms to form a process output current limit. When the accelerator pedal opening is ≥80%, no further reduction is made, and the aforementioned initial output current limit of 590Arms continues to be used. The reduction range of the current initial output current limit value can be flexibly set by those skilled in the art according to vehicle type, motor model, battery capacity and other conditions, which will not be described in detail here. In this step, the second hysteresis coefficient is also set for the preset opening. When the opening of the accelerator pedal drops back to the preset opening, due to the setting of the second hysteresis coefficient, when the actual value of the preset opening reached when the opening of the accelerator pedal drops is less than the actual value of the preset opening reached when it rises, it can return to the initial output current limit value before the reduction, so that the initial output current limit value output by the motor controller remains stable to prevent fluctuations.

[0040] The first hysteresis coefficient and the second hysteresis coefficient may also be flexibly set by those skilled in the art according to vehicle type, motor model, battery capacity and other conditions.

[0041] Limitation: The current torque limit is determined based on the current motor speed and the initial output current limit or the process output current limit. After the two physical quantities of speed and current limit are obtained, the interval gear position where the obtained speed and current limit are located is determined according to the interval gear position divided by the two physical quantities, and then the torque limit is determined by looking up the table. Because the current output by the motor controller is positively correlated with the torque output by the motor, limiting the maximum torque of the motor controller can limit the output current, thereby protecting the hardware safety. Specifically in this embodiment, the relationship between the gear range of the speed and current limit and the torque limit is as shown in the following table:

[0042]

[0043] It should also be noted that the vehicle model targeted by this implementation is a compact vehicle, including a compact sedan and a compact SUV. When facing other different vehicle models such as mid-sized vehicles and medium-to-large vehicles, the torque limit can be adaptively adjusted by those skilled in the art according to the actual vehicle model during debugging and calibration. The specific adjustment method is the prior art known in the art and is not limited here. Those skilled in the art should know that the torque limit in the table is only a preferred method specific to this embodiment, and is not a limitation of the technical solution.

[0044] After determining the current torque limit, the driver's required torque is determined according to the current motor speed and the current accelerator pedal opening. The driver's required torque is the product of the accelerator pedal opening and the maximum torque limit. The maximum torque limit is obtained by the motor speed and obtained by table lookup. Specifically in this embodiment, the relationship between the motor speed acquisition and the maximum torque limit is as follows:

[0045]

[0046] It should also be noted that the vehicle model targeted by this implementation is a compact vehicle, including a compact sedan and a compact SUV. When facing other different vehicle models such as mid-sized vehicles and medium-to-large vehicles, the maximum torque limit can be adaptively adjusted by those skilled in the art according to the actual vehicle model during debugging and calibration. The specific adjustment method is the prior art known in the art and is not limited here. Those skilled in the art should know that the maximum torque limit in the table is only a preferred method specific to this embodiment, and is not a limitation of the technical solution.

[0047] After determining the driver's required torque, adjust the coolant pump gear according to the driver's required torque, including:

[0048] If the required torque is greater than or equal to the current torque limit, the coolant pump gear is raised by one gear, otherwise the coolant pump gear is maintained. Through adjustment, the current vehicle condition is judged in time, and the coolant pump gear is adjusted according to the vehicle condition, so that the cooling level is more matched with the current heat dissipation, and the torque limit effect is also improved.

[0049] If the coolant water pump gear is adjusted up one gear, the initial determination step, the determination step and the amplitude limiting step are re-executed according to the adjusted water pump gear. Since the water pump gear has changed, the initial output current limit is re-adjusted according to the changed gear, so that the amplitude limiting is more accurate, and the whole set of adjustment methods forms a closed loop.

[0050] The torque limiting method provided in this embodiment can determine the maximum output peak current available under the current conditions, and dynamically limit the current peak output by the motor controller to control the torque output by the motor. Under the premise of meeting the system safety and reliability, the capabilities of the motor controller are maximized. At the same time, the accelerator pedal is used as a judge of the driver's intention. When there is no strong power performance requirement, the current of the motor controller is again limited to a certain extent to ensure hardware safety.

[0051] At the same time, this embodiment also provides a computer device, including a memory and a processor, the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the above-mentioned point cloud semantic segmentation method.

[0052] It will be appreciated by those skilled in the art that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. Accordingly, the computer program can be stored in a non-volatile computer-readable storage medium, and the computer program can implement the method of any of the above-mentioned embodiments when executed. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0053] Furthermore, this embodiment further provides a motor vehicle having a motor and a motor controller, wherein the motor controller controls the motor by the aforementioned torque limiting method.

[0054] or the motor vehicle has the aforementioned computer equipment;

[0055] Or the motor vehicle has the aforementioned computer-readable storage medium, and the aforementioned torque limiting method is implemented when the computer program is executed by the processor.

[0056] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification that does not deviate from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

1. A torque limiting method, characterized in that: The motor controller limits the output torque of the motor by the torque limiting method, including the following steps: Initial setting: Get the water inlet temperature of the coolant flow channel at the motor controller, the coolant pump gear and the battery voltage at the current moment, and get the current initial output current limit value according to the water inlet temperature, the water pump gear and the battery voltage; Determination: obtaining the opening of the accelerator pedal at the current moment, judging whether the current initial output current limit needs to be limited according to the opening of the accelerator pedal; when the opening of the accelerator pedal is greater than or equal to the preset opening, the current initial output current limit is adopted; when the opening of the accelerator pedal is less than the preset opening, the current initial output current limit is reduced to form a process output current limit; Limitation: The current torque limit is determined based on the current motor speed and the initial output current limit or process output current limit.

2. The torque limiting method according to claim 1, characterized in that: In the initial determination step, the water inlet temperature, the water pump gear, and the battery voltage are respectively provided with gear boundary values, and the gear boundary values ​​are provided with a first hysteresis coefficient.

3. The torque limiting method according to claim 1, characterized in that: In the determination step, the preset opening is provided with a second hysteresis coefficient.

4. The torque limiting method according to any one of claims 1 to 3, characterized in that: After the current torque limit is determined, the driver's required torque is determined according to the current motor speed and the opening of the accelerator pedal at the current moment, and the coolant water pump gear is adjusted according to the required torque.

5. The torque limiting method according to claim 4, characterized in that: The driver's required torque is the product of the accelerator pedal opening and the maximum torque limit, and the maximum torque limit is obtained by the motor speed.

6. The torque limiting method according to claim 4, characterized in that: Adjusting the water pump gear position of the coolant according to the required torque includes: If the required torque is greater than or equal to the current torque limit, the gear of the coolant water pump is increased by one gear, otherwise the gear of the coolant water pump is maintained.

7. The torque limiting method according to claim 6, characterized in that: If the coolant water pump gear is raised by one gear, the initialization step, the determination step and the limiting step are re-executed according to the adjusted water pump gear.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the torque limiting method according to any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the torque limiting method according to any one of claims 1 to 7 is implemented.

10. A motor vehicle, characterized in that: The motor vehicle has a motor and a motor controller, and the motor controller controls the motor by the torque limiting method according to any one of claims 1 to 7; or the motor vehicle has the computer device according to claim 8; Or the motor vehicle has the computer-readable storage medium of claim 9, and the computer program implements the torque limiting method of any one of claims 1 to 7 when executed by a processor.

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