A motor controller pre-torque control method and system

Abstract

The application discloses a motor controller pre-torque control method, comprising the following steps: outputting a pre-torque target instruction based on a pre-torque loading curve according to a current operation mode of a vehicle and an accelerator pedal opening degree; executing torque output according to the pre-torque target instruction and monitoring a torque loading process; comparing an actual torque value output with a torque target value in the pre-torque target instruction, and adjusting the pre-torque target instruction according to a comparison result. The application discloses a motor controller pre-torque control system, comprising a torque instruction pre-judgment module, a pre-torque starting execution module and an output torque monitoring module. Through a pre-torque loading curve based on a vehicle operation mode and a driver's intention, the torque output process is actively and smoothly intervened, and a real-time monitoring and feedback mechanism is utilized for dynamic fine adjustment, so that the predictive and smooth output of torque is realized under various complex working conditions, and the driving quality and riding comfort of the whole vehicle are greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicles, and particularly relates to a motor controller pre-torque control method and system. BACKGROUND

[0002] The motor controller is a control unit of an electric vehicle, and its basic task is to receive an instruction torque from a vehicle controller VCU and drive the motor to accurately output the torque.

[0003] However, in the traditional control strategy, the motor controller is often designed to output completely according to the received instruction torque. This control performs well in ideal working conditions, but in actual complex vehicle operating environments, when the driver quickly steps on or releases the accelerator pedal, or the vehicle driving condition changes suddenly, the step change of the torque instruction will be directly transmitted to the power transmission system. Due to the existence of elastic clearance and inertia of the transmission system itself, the sudden torque input is easy to cause torsional vibration of the transmission system, and ultimately is transmitted to the driver and passenger through the vehicle body, making them feel obvious jerk, shaking and other discomfort.

[0004] To solve the above technical problems, the technical personnel in the field propose a motor pre-torque correction method, device and electric vehicle. In the vehicle starting condition, the motor pre-torque is adjusted dynamically based on the analysis of the relationship between the specific sampling points to identify or estimate the shaking information by collecting motor speed and other signals, so as to actively suppress the shaking in the starting process. However, the control essence is a "reactive" or "compensation" control, that is, the correction is only made after the shaking information or its signs are detected, and the predictive control ability is weak. In addition, the application condition coverage range is narrow, and it is mainly designed for the single state of vehicle starting. For the jerk and shaking problems in the complex dynamic conditions such as acceleration and deceleration frequently occurring in the vehicle driving process, no effective solution is provided. SUMMARY

[0005] To solve the above technical problems, the present application provides a motor controller pre-torque control method and system.

[0006] To have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not a general review, nor is it intended to determine key / important components or delineate the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a prelude to the detailed description that follows.

[0007] The present application adopts the following technical solutions:

[0008] The present application provides a motor controller pre-torque control method, comprising:

[0009] According to the current operation mode of the vehicle and the accelerator pedal opening degree, a pre-torque target instruction is output based on a pre-torque loading curve, wherein the pre-torque loading curve is a curve of pre-torque changing with time;

[0010] The torque output is performed according to the pre-torque target instruction, and the torque loading process is monitored;

[0011] The actual torque value output is compared with the torque target value in the pre-torque target instruction, and the pre-torque target instruction is adjusted according to the comparison result.

[0012] Further, the pre-torque loading curve includes a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve.

[0013] Further, the process of outputting the pre-torque target instruction based on the driving and coasting process pre-torque loading curve and the process of outputting the pre-torque target instruction based on the driving and power generation switching process pre-torque loading curve both include the following steps:

[0014] In the pre-torque loading process at 0-t1, the pre-torque target instruction is that the torque jumps from 0 to Tr1 and then linearly increases to Tr2, Tr1 is a pre-torque starting value, Tr2 is a pre-torque ending value, and t1 is a preset value;

[0015] In the normal torque loading process after t1, after the pre-torque loading process is completed, the pre-torque target instruction is that the motor increases by a step, and the step time interval is 2 ms, Step is a preset value, and Tr3 is a target torque;

[0016] In the torque reduction process at t2-t3, i.e., the process of detecting that the accelerator pedal is released, the pre-torque target instruction is that a proportional reduction method is used in the torque reduction process, and the proportional reduction method is that the next beat torque is the current beat torque x a reduction proportionality coefficient, and each beat is 2 ms;

[0017] In the medium-high speed zero torque or small torque coasting process at t3-t4, when it is detected that the motor coasting speed is greater than a medium-high speed threshold value, if the VCU request torque is greater than Tr4, the pre-torque target instruction is to execute the VCU request torque, and if the VCU request torque is less than Tr4, the pre-torque target instruction is to execute the Tr4 torque, and when it is detected that the motor coasting speed is less than a low speed threshold value, the low speed zero torque or small torque coasting process is entered, the low speed threshold value is a keep torque switching speed threshold value x a keep torque switching speed hysteresis coefficient, and Tr4 is a medium speed keep torque.

[0018] Further, the process of outputting the pre-torque target instruction based on the driving and coasting process pre-torque loading curve further includes:

[0019] In the low-speed zero-torque or small-torque coasting process at t4-t5, when it is detected that the motor coasting speed is less than the low-speed threshold, if the VCU requested torque is greater than Tr1, the pre-torque target instruction is to execute the VCU requested torque, and if the VCU requested torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque.

[0020] Further, the process of outputting the pre-torque target instruction based on the pre-torque loading curve in the driving and coasting process further comprises:

[0021] t5 is the pre-torque zero time, and the pre-torque target instruction is pre-torque zero when the following three conditions are met simultaneously:

[0022] Condition one: the VCU issues 0 torque;

[0023] Condition two: it is detected that the current speed is less than the pre-torque exit speed threshold;

[0024] Condition three: in the process of switching the driving mode to the power generation / braking mode, the difference between the minimum torque output by the motor and the starting torque does not exceed 5% of the starting torque.

[0025] Further, the process of outputting the pre-torque target instruction based on the pre-torque loading curve in the driving and power generation switching process further comprises: in the low-speed zero-torque or small-torque coasting process at t4-t5, when it is detected that the motor coasting speed is less than the low-speed threshold, if the VCU requested torque is greater than Tr1, the pre-torque target instruction is to execute the VCU requested torque, if the VCU requested torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque, and when the VCU requested torque is braking, when it is detected that the real-time torque is less than Trmin, the process is directly switched to Tr1.

[0026] Trmin is the minimum torque at the time of power generation switching.

[0027] Further, when it is detected that the vehicle is in D gear and the accelerator pedal opening degree is the first opening degree threshold, the pre-torque loading process is executed.

[0028] When it is detected that the vehicle is in D gear and the accelerator pedal opening degree is the second opening degree threshold, the normal torque loading process is executed.

[0029] When it is detected that the vehicle is in D gear and the accelerator pedal opening degree changes from the second opening degree threshold to the first opening degree threshold, the torque reduction process / small-torque coasting process is executed.

[0030] When it is detected that the vehicle is in D gear and the accelerator pedal is released, the high-speed zero-torque process / low-speed zero-torque process is executed.

[0031] Further, the first opening degree threshold is that the accelerator pedal reaches 20% opening degree, and the second opening degree threshold is that the accelerator pedal reaches 70% opening degree.

[0032] A motor controller pre-torque control system is provided, comprising:

[0033] A torque instruction pre-judgment module is configured to output a pre-torque target instruction based on a pre-torque loading curve according to a current operation mode of the vehicle and an opening degree of the accelerator pedal, wherein the pre-torque loading curve is a curve of pre-torque changing with time.

[0034] A pre-torque starting execution module is configured to execute torque output according to the pre-torque target instruction.

[0035] An output torque monitoring module is configured to monitor the torque loading process, compare an actual torque value output with a torque target value in the pre-torque target instruction, and adjust the pre-torque target instruction according to a comparison result.

[0036] Further, the pre-torque loading curve comprises a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve.

[0037] The present application has the following beneficial effects: the present application actively and smoothly intervenes in the torque output process by using a pre-defined pre-torque loading curve based on the vehicle operation mode and the driver's intention, and dynamically fine-tunes by using a real-time monitoring and feedback mechanism, so as to realize the predictability and smoothness of torque output in various complex working conditions, such as starting, accelerating, coasting, energy recovery switching, etc., and greatly improve the driving quality and riding comfort of the vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0039] Figure 1 is a schematic diagram of the driving and coasting process pre-torque loading curve of the present application;

[0040] Figure 2 is a schematic diagram of the driving and power generation switching process pre-torque loading curve of the present application;

[0041] Figure 3 is a schematic diagram of a motor controller pre-torque control system of the present application. DETAILED DESCRIPTION

[0042] The embodiments of the present application will be described in detail below with reference to the drawings. It should be noted that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0043] The existing compensation type control mode such as start-up condition jitter correction can only respond after the jitter occurs, and the applicable working condition is single, and cannot cover the complex scene of frequent acceleration and deceleration in driving. Therefore, the present application provides a motor controller pre-torque control method, comprising the following steps:

[0044] According to the current running mode and the accelerator pedal opening degree of the vehicle, a pre-torque target instruction is output based on a pre-torque loading curve.

[0045] The running mode, such as driving, coasting and braking, and the accelerator pedal opening degree are direct input factors for judging the driver's intention and the working condition that the vehicle will enter. Based on the above input, the present application calls a preset pre-torque loading curve. As shown in the figure, Figures 1-2 The pre-torque loading curve is a curve of the change of pre-torque with time. The pre-torque loading curve includes a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve.

[0046] As shown in the figure, Figure 1 The driving and coasting process pre-torque loading curve covers the complete positive power process of the vehicle from starting, accelerating driving to releasing the accelerator for coasting, and avoids step change through multi-stage torque gradual change. As shown in the figure, Figure 2 The driving and power generation switching process pre-torque loading curve introduces a torque threshold Trmin to ensure smooth transition and prevent switching impact for the critical working condition that the vehicle switches from driving mode (motor output positive torque) to power generation / braking mode (motor output negative torque) which is prone to jerk.

[0047] Unlike the passive reaction mode of the prior art which only corrects after detecting jitter, the present application selects a smooth torque output path according to the working condition type in real time, which is a kind of active planning, and can avoid the excitation source that causes vibration from the source.

[0048] Then, torque output is performed according to the pre-torque target instruction, and the torque loading process is monitored. Specifically, after receiving the pre-torque target instruction, the drive motor performs torque output according to the instruction, and simultaneously monitors the torque loading process in real time to obtain the actual torque value of the motor output.

[0049] The actual output torque value is compared with the torque target value in the pre-torque target instruction, and the pre-torque target instruction is adjusted according to the comparison result.

[0050] The torque value actually output by the motor is collected in real time, which can be directly measured by a sensor or estimated based on a motor model and an observer. Meanwhile, the torque target value in the pre-torque target instruction is obtained, which is calculated according to the vehicle operating mode and the accelerator pedal opening degree in combination with the pre-torque loading curve. The actual output torque value is compared with the target torque value, and the instantaneous error is calculated.

[0051] The calculated instantaneous error is input into a PID controller, and the PID controller calculates a real-time correction instruction according to the numerical value, change trend and duration of the instantaneous error. The correction instruction is sent to an actuator (such as an inverter), and the actuator adjusts the motor voltage vector according to the correction instruction, so as to control the output torque of the motor. Through continuous instantaneous error calculation and PID control, the system can realize real-time sensing of the deviation between the actual output torque value of the motor and the torque target value and dynamic correction, so as to ensure that the output torque of the motor always remains near the torque target value.

[0052] The present application actively and smoothly intervenes in the torque output process based on the pre-torque loading curve defined in advance based on the vehicle operating mode and the driver's intention, and dynamically fine-tunes by using the real-time monitoring and feedback mechanism, so as to realize the predictable and smooth output of torque in various complex working conditions such as starting, accelerating, coasting and energy recovery switching, and greatly improve the driving quality and riding comfort of the vehicle.

[0053] As shown in Figure 1 The process of outputting the pre-torque target instruction based on the driving and coasting process pre-torque loading curve includes the following steps:

[0054] Pre-torque loading process:

[0055] In the pre-torque loading process at 0~t1, the pre-torque target instruction is that the torque jumps from 0 to Tr1 and then linearly increases to Tr2, Tr1 is the pre-torque starting value, Tr2 is the pre-torque ending value, and t1 is a preset value.

[0056] Tr1, Tr2 and t1 are all preset values, and the specific values are related to the driving form and power requirement of the vehicle. Among them, Tr2 needs to be maintained between 1.8-2.5 times of Tr1, and the setting time range of t1 is between 0.1s and 0.4s.

[0057] The setting of the pre-torque starting value Tr1 can quickly eliminate the gear clearance in the transmission system, such as the half shaft and the reducer, and provide a non-impact mechanical basis for subsequent linear loading, and can directly solve the gear impact problem. After the clearance is eliminated, the torque is linearly increased at a fixed slope, which can avoid the impact caused by the torque directly stepping from zero to a larger value, and further make the vehicle start or accelerate more smoothly, and inhibit the generation of shaking.

[0058] Normal torque loading process:

[0059] In the normal torque loading process after the t1 moment, after the pre-torque loading process is completed, the pre-torque target instruction is increased by a step Step for the motor until Tr3 is reached, the step time interval is 2 ms, Step is a preset value, and Tr3 is a target torque. Tr3 is an actual target torque, and Step is a torque loading step, both of which are obtained according to a calibration result.

[0060] After the pre-torque phase is completed, the system executes a step-by-step loading phase. Compared with continuous linear loading, the step-by-step loading mode of every 2 ms of Step is more in line with the discrete characteristics of the digital control system, is convenient for the MCU to accurately calculate and execute, and can ensure the smoothness of the torque rise until the driver's final target torque Tr3 is reached.

[0061] Torque reduction process:

[0062] In the torque reduction process at the t2-t3 moment, that is, the process of detecting that the accelerator pedal is released, the pre-torque target instruction adopts a proportional reduction mode in the torque reduction process. The proportional reduction mode refers to that the next beat torque is the current beat torque multiplied by a reduction proportional coefficient, and each beat is 2 ms.

[0063] When the driver releases the accelerator, if the torque is instantaneously zero, a strong jerk will be caused. The proportional reduction mode is adopted in the present application, that is, when the reduction starts, Trq1=Tr3×reduction proportional coefficient, and the next beat Trq2=Trq1×reduction proportional coefficient, and so on. The torque is smoothly attenuated according to an exponential law, which greatly improves the comfort and predictability of driving.

[0064] Medium and high speed zero torque / small torque coasting process:

[0065] In the medium and high speed zero torque or small torque coasting process at the t3-t4 moment, when it is detected that the motor coasting speed is greater than a medium and high speed threshold value, if the VCU request torque is greater than Tr4, the pre-torque target instruction is to execute the VCU request torque, if the VCU request torque is less than Tr4, the pre-torque target instruction is to execute the Tr4 torque, when it is detected that the motor coasting speed is less than or equal to the medium and high speed threshold value, the t4-t5 running process is executed, and when it is detected that the motor coasting speed is less than a low speed threshold value, the low speed zero torque or small torque coasting process is entered.

[0066] Wherein, the medium-high speed threshold is the speed threshold when the torque is maintained, the low speed threshold is the speed threshold when the torque is maintained, and the low speed threshold is the speed threshold when the torque is maintained x the speed hysteresis coefficient when the torque is maintained.

[0067] Tr4 is the medium speed maintained torque. Tr4 and the low speed threshold are both preset values, which are set according to the maintained torque when the actual jitter occurs and the current speed, and Tr4 is required to be ≥ the jitter maintained torque, and the value is fixed according to the actual calibration.

[0068] When the medium-high speed coasting / small torque coasting occurs, there is still some friction and wind resistance in the transmission system, and maintaining the medium speed maintained torque Tr4 can maintain the slight pre-tightening force of the transmission system, so as to avoid the gap feeling or impact when the driver steps on the accelerator again because the system enters the tension state from the completely relaxed state.

[0069] Low speed zero torque / small torque coasting process:

[0070] In the low speed zero torque / small torque coasting process at t4~t5, when it is detected that the motor coasting speed is less than the low speed threshold, if the VCU requested torque is greater than Tr1, the pre-torque target instruction is to execute the VCU requested torque, and if the VCU requested torque is less than Tr1, the pre-torque target instruction is to execute Tr1 torque.

[0071] When the low speed zero torque / small torque coasting occurs, the gap of the transmission system is more significant, and maintaining Tr1 can make good instant and non-impact preparation for the next possible acceleration or braking.

[0072] Pre-torque zeroing:

[0073] t5 is the pre-torque zeroing time, and when the following three conditions are met at the same time, the pre-torque target instruction is pre-torque zeroing:

[0074] Condition one: the VCU issues 0 torque;

[0075] Condition two: it is detected that the current speed is less than the pre-torque exit speed threshold;

[0076] Condition three: the difference between the minimum torque output by the motor and the starting torque during the process of switching the driving mode to the power generation / braking mode is not more than 5% of the starting torque.

[0077] When the VCU requests zero torque, extremely low speed, and extremely low output torque, the pre-torque is cleared to zero, ensuring that the pre-torque is only canceled in a stable state where the vehicle is completely stationary and has no power demand. When switching from drive mode to generator / braking mode, if the torque change is too rapid or too large, it can easily cause severe mechanical shock to the transmission system, resulting in vehicle jerking or vibration. Condition three, by limiting the difference between the minimum torque and the starting torque to no more than 5%, ensures the smoothness of torque changes during the switching process, thus avoiding the discomfort caused by sudden torque changes. This avoids the discomfort caused by the sudden disappearance of pre-torque just before the vehicle stops, while also ensuring that the motor does not continuously output unnecessary micro-torque after the vehicle has come to a complete stop, balancing comfort, safety, and energy efficiency.

[0078] like Figure 2 As shown, the process of outputting the pre-torque target command based on the pre-torque loading curve during the drive and generation switching process includes:

[0079] Pre-torque loading process:

[0080] During the pre-torque loading process from time 0 to t1, the target pre-torque command is for the torque to jump from 0 to Tr1, and then increase linearly to Tr2. Tr1 is the initial value of the pre-torque, Tr2 is the final value of the pre-torque, and t1 is the preset value.

[0081] Setting the initial pre-torque value Tr1 can quickly eliminate backlash in the transmission system, such as in the half-shafts and reducers, providing a shock-free mechanical basis for subsequent linear loading and directly solving the gear impact problem. After eliminating backlash, the torque increases linearly with a fixed slope, avoiding the impact caused by the torque jumping directly from zero to a large value, thus making the vehicle start or accelerate more smoothly and suppressing the generation of vibration.

[0082] Normal torque loading process:

[0083] During the normal torque loading process after time t1, after the pre-torque loading process is completed, the pre-torque target command is for the motor to increase by step size Step until it reaches Tr3. The step size interval is 2ms, Step is a preset value, and Tr3 is the target torque.

[0084] After the pre-torque phase is completed, the system executes the step loading phase. Compared with continuous linear loading, the step loading method with a step every 2ms is more in line with the discrete characteristics of the digital control system, which facilitates accurate calculation and execution by the MCU, and can ensure the smoothness of torque increase until the driver's final target torque Tr3 is reached.

[0085] Torque reduction process:

[0086] In the torque reduction process at t2~t3, i.e. the process of detecting the accelerator pedal release, the pre-torque target instruction is in a proportional reduction mode in the torque reduction process. The proportional reduction mode refers to that the next beat torque is the current beat torque x the reduction proportionality coefficient, and each beat is 2ms.

[0087] When the driver releases the accelerator, if the torque instantaneously returns to zero, it will cause a strong jerk. The present application adopts the proportional reduction mode, i.e. when starting to reduce, Trq1=Tr3x reduction proportionality coefficient, and the next beat Trq2=Trq1x reduction proportionality coefficient, and so on. The torque is smoothly attenuated according to the exponential law, which greatly improves the driving comfort and predictability.

[0088] Medium-high speed zero torque / small torque coasting process:

[0089] In the medium-high speed zero torque or small torque coasting process at t3~t4, when the detected motor coasting speed is greater than the medium-high speed threshold, if the VCU requested torque is greater than Tr4, the pre-torque target instruction is to execute the VCU requested torque, and if the VCU requested torque is less than Tr4, the pre-torque target instruction is to execute the Tr4 torque, and when the detected motor coasting speed is less than the low speed threshold, the low speed zero torque or small torque coasting process is entered, the low speed threshold is the speed threshold at the time of maintaining torque switching x the speed hysteresis coefficient at the time of maintaining torque switching, and Tr4 is the medium speed maintaining torque.

[0090] In the medium-high speed coasting / small torque coasting, there is still some friction and wind resistance in the transmission system, and maintaining the medium speed maintaining torque Tr4 can maintain the slight pre-tightening force of the transmission system, avoiding the gap feeling or impact when the driver steps on the accelerator again due to the system from the completely relaxed state to the tense state.

[0091] Low speed zero torque / small torque coasting process:

[0092] In the low speed zero torque or small torque coasting process at t4~t5, when the detected motor coasting speed is less than the low speed threshold, if the VCU requested torque is greater than Tr1, the pre-torque target instruction is to execute the VCU requested torque, and if the VCU requested torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque.

[0093] In the low speed zero torque / small torque coasting, the gap of the transmission system is more significant, and maintaining Tr1 can prepare for the next possible acceleration or braking instantaneously and without impact.

[0094] Moreover, when the VCU requested torque is braking, when the detected real-time torque is less than Trmin, it is directly switched to Tr1; Trmin is the minimum torque at the time of electric motor / generator switching.

[0095] The switching from driving (positive torque) to power generation (negative torque) needs to cross the zero point of the torque curve. If the torque is directly switched from a large positive torque to a negative torque, the torque step will cause severe vehicle pitching and jerk. The present application is designed to first decay the torque to a value close to zero, Trmin, and then to Tr1, which can be understood as a small pre-braking torque in the power generation mode. The above design ensures the continuity and smoothness of the torque at the zero crossing point, and solves the impact when switching between driving and braking.

[0096] When the vehicle is detected to be in D gear and the accelerator pedal opening is the first opening threshold, the pre-torque loading process is performed; when the vehicle is detected to be in D gear and the accelerator pedal opening is the second opening threshold, the normal torque loading process is performed; when the vehicle is detected to be in D gear and the accelerator pedal opening changes from the second opening threshold to the first opening threshold, the torque reduction process / small torque coasting process is performed; when the vehicle is detected to be in D gear and the accelerator pedal is released, the medium-high speed zero torque process / low speed zero torque process is performed.

[0097] The first opening threshold is that the accelerator pedal reaches 20% opening, and the second opening threshold is that the accelerator pedal reaches 70% opening.

[0098] The pre-torque loading at 20% opening can quickly eliminate the transmission system gap and prepare for subsequent power output; while the normal torque loading at 70% opening indicates that the driver has a strong acceleration demand, and the system quickly increases the torque to meet the power requirement. When the accelerator opening decreases from 70% to 20%, the system enters the torque reduction or small torque coasting process to achieve smooth torque decay. This segmented control not only improves the flexibility of power response, but also optimizes energy utilization efficiency, especially in the process of coasting and energy recovery, which can more accurately match the driver's intention and system state.

[0099] By combining the accelerator opening threshold with the D gear state, the driver's intention is recognized and switched to the corresponding torque control mode. For example, when the accelerator is released, the medium-high speed / low speed zero torque process is entered, which is suitable for coasting or scenarios where the vehicle is about to stop; while the accelerator is kept at about 20%, the system maintains small torque output to respond to possible acceleration demand. This switching mechanism improves the adaptability of the system to complex driving scenarios, so that the vehicle can maintain good control under different driving habits and road conditions.

[0100] As shown in Figure 3 The present application provides a motor controller pre-torque control system, which comprises:

[0101] The torque instruction pre-judgment module is configured to output a pre-torque target instruction based on a pre-torque loading curve according to a current operation mode of the vehicle and an accelerator pedal opening degree, wherein the pre-torque loading curve is a curve of pre-torque changing with time, and the pre-torque loading curve comprises a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve.

[0102] The pre-torque starting execution module is configured to execute torque output according to the pre-torque target instruction.

[0103] The output torque monitoring module is configured to monitor the torque loading process, compare an actual torque value output with a torque target value in the pre-torque target instruction, and adjust the pre-torque target instruction according to a comparison result.

[0104] The torque instruction pre-judgment module is configured to output a pre-torque target instruction based on a pre-torque loading curve according to a current operation mode of the vehicle and an accelerator pedal opening degree, wherein the pre-torque loading curve is a curve of pre-torque changing with time, and the pre-torque loading curve comprises a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve.

[0105] Compared with the prior art, the motor controller pre-torque control method and system have the following advantages:

[0106] The pre-torque loading curve is used to actively plan and execute a smooth output path before the torque demand changes, which fundamentally avoids torque mutation causing vibration and actively adapts.

[0107] The scheme not only optimizes the starting condition, but also covers the pre-torque strategy of driving, coasting, deceleration, driving / power generation switching and other daily driving conditions.

[0108] By designing each stage of torque loading, maintaining, reducing and clearing, such as jump, linear loading, stepwise increase, proportional decrease and multi-level maintenance, the control of the torque change process is realized, so that the torque change rate at any moment is within a controllable range, thereby improving the driving experience.

[0109] The closed-loop feedback mechanism of monitoring, comparing and adjusting is introduced, so that the system can sense the deviation between the actual output and the target instruction in real time and dynamically correct it.

[0110] The above merely illustrates the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method of pre-torque control of a motor controller, characterized by, The method comprises the following steps: outputting a pre-torque target instruction based on a pre-torque loading curve according to a current operation mode of the vehicle and an accelerator pedal opening degree, wherein the pre-torque loading curve is a curve of pre-torque changing with time; performing torque output according to the pre-torque target instruction and monitoring the torque loading process; comparing an actual torque value output with a torque target value in the pre-torque target instruction, and adjusting the pre-torque target instruction according to a comparison result; the pre-torque loading curve comprises a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve; the process of outputting the pre-torque target instruction based on the driving and coasting process pre-torque loading curve and the process of outputting the pre-torque target instruction based on the driving and power generation switching process pre-torque loading curve both comprise the following steps: in a pre-torque loading process at 0-t1, the pre-torque target instruction is that the torque jumps from 0 to Tr1 and then linearly increases to Tr2, Tr1 is a pre-torque starting value, Tr2 is a pre-torque ending value, and t1 is a preset value; in a normal torque loading process after t1, after the pre-torque loading process is completed, the pre-torque target instruction is that the motor increases by a step Step until Tr3 is reached, the step time interval is 2 ms, Step is a preset value, and Tr3 is a target torque; in a torque reduction process at t2-t3, i.e. a process in which the accelerator pedal is detected to be released, the pre-torque target instruction is that a proportional reduction mode is used in the torque reduction process, wherein the next beat torque is the current beat torque multiplied by a reduction proportionality coefficient, and each beat is 2 ms; in a medium-high speed zero torque or small torque coasting process at t3-t4, when the motor coasting speed is detected to be greater than a medium-high speed threshold value, if the VCU request torque is greater than Tr4, the pre-torque target instruction is to execute the VCU request torque, and if the VCU request torque is less than Tr4, the pre-torque target instruction is to execute the Tr4 torque, and when the motor coasting speed is detected to be less than a low speed threshold value, a low speed zero torque or small torque coasting process is entered, wherein the low speed threshold value is a speed threshold value at the time of holding torque switching multiplied by a speed hysteresis coefficient at the time of holding torque switching, and Tr4 is a medium speed holding torque; in a low speed zero torque or small torque coasting process at t4-t5, when the motor coasting speed is detected to be less than the low speed threshold value, if the VCU request torque is greater than Tr1, the pre-torque target instruction is to execute the VCU request torque, and if the VCU request torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque; in the low speed zero torque or small torque coasting process at t4-t5, when the motor coasting speed is detected to be less than the low speed threshold value, if the VCU request torque is greater than Tr1, the pre-torque target instruction is to execute the VCU request torque, and if the VCU request torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque, and when the VCU request torque is braking, when the real-time torque is detected to be less than Trmin, the process is directly switched to Tr1; and Trmin is a minimum torque at the time of electric power generation switching. t5 is a pre-torque zero time, and the pre-torque target instruction is pre-torque zero when the following three conditions are met simultaneously: Condition one: the VCU issues 0 torque; Condition two: the current speed is detected to be less than a pre-torque exit speed threshold; Condition three: the difference between the minimum torque output by the motor and the starting torque does not exceed 5% of the starting torque during the process of switching the driving mode to the power generation / braking mode.

2. The method of claim 1, wherein, When it is detected that the vehicle is in D gear and the accelerator pedal opening is a first opening threshold, a pre-torque loading process is performed; When it is detected that the vehicle is in D gear and the accelerator pedal opening is a second opening threshold, a normal torque loading process is performed; When it is detected that the vehicle is in D gear and the accelerator pedal opening changes from the second opening threshold to the first opening threshold, a torque reduction process / small torque coasting process is performed; When it is detected that the vehicle is in D gear and the accelerator pedal is released, a high-speed zero-torque process / low-speed zero-torque process is performed.

3. A method of pre-torque control of a motor controller according to claim 2, characterized in that, The first opening threshold is that the accelerator pedal reaches 20% opening, and the second opening threshold is that the accelerator pedal reaches 70% opening.

4. A motor controller pre-torque control system, characterized by, The method comprises: a torque instruction pre-judgment module, configured to output a pre-torque target instruction based on a pre-torque loading curve according to the current running mode of the vehicle and the accelerator pedal opening, wherein the pre-torque loading curve is a curve of pre-torque changing over time; the pre-torque loading curve comprises a driving and coasting process pre-torque loading curve and a driving and power generation switching process pre-torque loading curve a pre-torque start execution module, configured to perform torque output according to the pre-torque target instruction; an output torque monitoring module, configured to monitor the torque loading process and compare the actual torque value output with the torque target value in the pre-torque target instruction, and adjust the pre-torque target instruction according to the comparison result; the process of outputting the pre-torque target instruction based on the driving and coasting process pre-torque loading curve, and the process of outputting the pre-torque target instruction based on the driving and power generation switching process pre-torque loading curve both comprise the following steps: in the pre-torque loading process at 0-t1, the pre-torque target instruction is that the torque jumps from 0 to Tr1 and then increases linearly to Tr2, Tr1 is a pre-torque starting value, Tr2 is a pre-torque ending value, and t1 is a preset value; in the normal torque loading process after t1, after completing the pre-torque loading process, the pre-torque target instruction is that the motor increases by a step, until Tr3 is reached, the step time interval is 2 ms, Step is a preset value, and Tr3 is a target torque; in the torque reduction process at t2-t3, i.e., the process of detecting that the accelerator pedal is released, the pre-torque target instruction is that a proportional reduction method is used in the torque reduction process, and the proportional reduction method is that the next beat torque is the current beat torque multiplied by a reduction proportionality coefficient, and each beat is 2 ms. In the medium-high speed zero torque or small torque coasting process at t3~t4, when the motor coasting speed is detected to be greater than the medium-high speed threshold, if the VCU requested torque is greater than Tr4, the pre-torque target instruction is to execute the VCU requested torque, if the VCU requested torque is less than Tr4, the pre-torque target instruction is to execute the Tr4 torque, and when the motor coasting speed is detected to be less than the low speed threshold, the low speed zero torque or small torque coasting process is entered, the low speed threshold is the speed threshold at the time of the holding torque switching x the speed hysteresis coefficient at the time of the holding torque switching, and Tr4 is the medium speed holding torque; In the low speed zero torque or small torque coasting process at t4~t5, when the motor coasting speed is detected to be less than the low speed threshold, if the VCU requested torque is greater than Tr1, the pre-torque target instruction is to execute the VCU requested torque, if the VCU requested torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque; In the low speed zero torque or small torque coasting process at t4~t5, when the motor coasting speed is detected to be less than the low speed threshold, if the VCU requested torque is greater than Tr1, the pre-torque target instruction is to execute the VCU requested torque, if the VCU requested torque is less than Tr1, the pre-torque target instruction is to execute the Tr1 torque, and when the VCU requested torque is braking, when the real-time torque is detected to be less than Trmin, the Tr1 is directly switched to; Trmin is the minimum torque at the time of the motor generator switching; t5 is the pre-torque zero time, when the following three conditions are met simultaneously, the pre-torque target instruction is pre-torque zero: Condition one: the VCU issues 0 torque; Condition two: the current speed is detected to be less than the pre-torque exit speed threshold; Condition three: in the process of switching the driving mode to the power generation / braking mode, the difference between the minimum torque output by the motor and the starting torque does not exceed 5% of the starting torque.

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