New energy automobile wheel anti-slip control method and device and computer program product

Abstract

The invention discloses a new energy automobile wheel anti-slip control method and device and a computer program product. Automobile CAN signals are processed, and the target torque of a whole automobile, the actual rotating speed of a motor, the wheel speed of a driving left wheel and the wheel speed of a driving right wheel are analyzed; based on the actual rotating speed of the motor, the wheel speed of the driving left wheel and the wheel speed of the driving right wheel, the absolute value of the rotating speed fluctuation quantity and the absolute value of the wheel speed difference are calculated and obtained, the absolute value of the wheel speed difference serves as input of a PI controller, and anti-slip torque is output through the PI controller; a torque correction database is established, the torque correction database contains a plurality of sets of absolute values of the rotating speed fluctuation quantity, the absolute value of the wheel speed difference and anti-slip torque correction coefficients corresponding to the absolute values, and the corresponding anti-slip torque correction coefficients are obtained through the torque correction database; and based on the obtained anti-slip torque correction coefficient, the anti-slip torque is corrected, and the target torque of the whole vehicle and the corrected anti-slip torque are accumulated to obtain the target torque of a motor torque ring.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and particularly relates to a control method, device and computer program product for preventing wheel skidding of new energy vehicles. Background Art

[0002] With the rapid development of electric vehicle technology, vehicle torque control has become one of the core technologies affecting vehicle power performance, safety and driving experience. As the center of the power system, the vehicle control unit (VCU) calculates the target torque by collecting parameters such as the throttle pedal opening, motor speed, battery state of charge (SOC), etc. in real time, and dynamically limits it to achieve the balance between power output and system safety. However, in actual operation, there is often a dynamic deviation between the target torque output by the vehicle control unit (VCU) and the torque actually executed by the motor control unit (MCU). This difference will cause insufficient torque correction of the motor control unit (MCU), and the wheel-end torque may instantaneously exceed the road adhesion, resulting in tire skidding and threatening driving safety. Summary of the Invention

[0003] Aiming at the deficiencies of the above-mentioned prior art, the technical problem to be solved by the present invention is: how to provide a control method for preventing wheel skidding of new energy vehicles that can improve the cooperative control of the vehicle control unit and the motor control unit and enhance vehicle safety.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A control method for preventing wheel skidding of a new energy vehicle, which processes the vehicle's CAN signals, analyzes the vehicle's target torque VCUTqReq, the actual motor speed MotSpd, the driving left wheel speed LeftWheelSpd, and the driving right wheel speed RightWheelSpd; based on the actual motor speed MotSpd, the driving left wheel speed LeftWheelSpd, and the driving right wheel speed RightWheelSpd, calculates the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff, and uses the absolute value of the wheel speed difference WhlSpdDiff as the input of the PI controller, and uses the PI controller to output the anti-skid torque AntiSlipTq; establishes a torque correction database, in which there are several groups of the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff and the corresponding anti-skid torque correction coefficient AntiSlipFactor, and the corresponding anti-skid torque correction coefficient AntiSlipFactor can be obtained through the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff in the torque correction database, and corrects the anti-skid torque AntiSlipTq based on the obtained anti-skid torque correction coefficient AntiSlipFactor, accumulates the vehicle's target torque VCUTqReq and the corrected anti-skid torque ReAntiSlipTq to obtain the target torque TqLoopTrq of the motor torque loop.

[0006] As an optimization, establish a PI controller anti-skid parameter database, in which there are several groups of the absolute value of the wheel speed difference WhlSpdDiff and the corresponding anti-skid proportional coefficient P and anti-skid integral coefficient I of the PI controller, and obtain the anti-skid proportional coefficient P and anti-skid integral coefficient I of the PI controller based on the absolute value of the wheel speed difference WhlSpdDiff.

[0007] As an optimization, use a high-pass filter HPF to filter out the low-frequency interference signal of the actual motor speed MotSpd, use a low-pass filter LPF to suppress the high-frequency noise of the actual motor speed MotSpd, and obtain the effective fluctuation signal of the actual motor speed MotSpd through the combination of the high-pass filter HPF and the low-pass filter LPF.

[0008] As an optimization, the actual motor speed MotSpd is used as the input of the PI controller, and the anti-shake torque MotDampTq is output by the PI controller. There are also several groups of the absolute value of the rotational speed fluctuation deltaSpd, the absolute value of the wheel speed difference WhlSpdDiff, and the corresponding anti-shake torque correction coefficient DampFactor in the torque correction database. The corresponding anti-shake torque correction coefficient DampFactor can be obtained through the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff in the torque correction database. The anti-shake torque MotDampTq is corrected based on the obtained anti-shake torque correction coefficient DampFactor, and the vehicle target torque VCUTqReq, the corrected anti-slip torque ReAntiSlipTq, and the corrected anti-shake torque ReMotDampTq are accumulated to obtain the motor torque loop target torque TqLoopTrq.

[0009] As an optimization, an anti-shake parameter database for the PI controller is established. There are several groups of motor speeds, the vehicle target torque VCUTqReq, and the corresponding anti-shake proportional coefficient P and anti-shake integral coefficient I of the PI controller in the anti-shake parameter database for the PI controller. The anti-shake proportional coefficient P and anti-shake integral coefficient I of the PI controller are obtained based on the actual motor speed MotSpd and the vehicle target torque VCUTqReq.

[0010] A computer-readable storage medium stores a computer program thereon. When the computer program is executed by a computer, the method described above is implemented.

[0011] A computer program product includes a computer program. When the computer program is executed by a computer, the method described above is implemented.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] (1) The present invention improves the torque precise cooperative control between the vehicle control unit (VCU) and the motor control unit (MCU), thereby suppressing the wheel slip phenomenon of electric vehicles and significantly improving the vehicle power safety and handling stability;

[0014] (2) The present invention improves the coordination between torque control accuracy and NVH performance. By real-time analyzing the vehicle target torque and the actual motor speed in the CAN bus, combining with the PI controller to dynamically generate anti-shake torque, and matching the torque correction coefficient based on the rotational speed fluctuation amount, it effectively compensates for the motor dynamic response lag and algorithm error, can suppress the high-frequency fluctuation amplitude, avoids the resonance of the transmission chain, and significantly improves the vehicle NVH performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1This is a schematic diagram of the control flow of the present invention. Detailed implementation manners

[0016] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. Components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0017] As Figure 1 shown, in the control method for preventing wheel skidding of a new energy vehicle in this detailed implementation manner, the automotive CAN signal is processed to analyze the vehicle target torque VCUTqReq, the actual motor speed MotSpd, the driving left wheel speed LeftWheelSpd, and the driving right wheel speed RightWheelSpd; based on the actual motor speed MotSpd, the driving left wheel speed LeftWheelSpd, and the driving right wheel speed RightWheelSpd, the absolute value deltaSpd of the rotational speed fluctuation amount and the absolute value WhlSpdDiff of the wheel speed difference are calculated, and the absolute value WhlSpdDiff of the wheel speed difference is used as the input of the PI controller, and the anti-skid torque AntiSlipTq is output by the PI controller; a torque correction database is established, and the torque correction database has several groups of the absolute value deltaSpd of the rotational speed fluctuation amount, the absolute value WhlSpdDiff of the wheel speed difference, and the corresponding anti-skid torque correction factor AntiSlipFactor. The above data are obtained through several tests. The corresponding anti-skid torque correction factor AntiSlipFactor can be obtained through the absolute value deltaSpd of the rotational speed fluctuation amount and the absolute value WhlSpdDiff of the wheel speed difference in the torque correction database. The anti-skid torque AntiSlipTq is corrected based on the obtained anti-skid torque correction factor AntiSlipFactor, and the vehicle target torque VCUTqReq and the corrected anti-skid torque ReAntiSlipTq are accumulated to obtain the motor torque loop target torque TqLoopTrq.

[0018] In this specific embodiment, a database of anti-slip parameters for the PI controller is established. The database of anti-slip parameters for the PI controller contains several sets of the absolute value of the wheel speed difference WhlSpdDiff and the corresponding anti-slip proportional coefficient P and anti-slip integral coefficient I of the PI controller. The above data is obtained through several tests, and the anti-slip proportional coefficient P and anti-slip integral coefficient I of the PI controller are obtained based on the absolute value of the wheel speed difference WhlSpdDiff.

[0019] In this specific embodiment, a high-pass filter HPF is used to filter out the low-frequency interference signal of the actual motor speed MotSpd, and a low-pass filter LPF is used to suppress the high-frequency noise of the actual motor speed MotSpd. The effective fluctuation signal of the actual motor speed MotSpd is obtained through the combination of the high-pass filter HPF and the low-pass filter LPF.

[0020] In this specific embodiment, the actual motor speed MotSpd is used as the input of the PI controller, and the anti-shake torque MotDampTq is output by the PI controller. The torque correction database also contains several sets of the absolute value of the rotational speed fluctuation deltaSpd, the absolute value of the wheel speed difference WhlSpdDiff, and the corresponding anti-shake torque correction coefficient DampFactor. The corresponding anti-shake torque correction coefficient DampFactor can be obtained through the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff in the torque correction database. The anti-shake torque MotDampTq is corrected based on the obtained anti-shake torque correction coefficient DampFactor, and the vehicle target torque VCUTqReq, the corrected anti-slip torque ReAntiSlipTq, and the corrected anti-shake torque ReMotDampTq are accumulated to obtain the target torque TqLoopTrq of the motor torque loop.

[0021] In this specific embodiment, a database of anti-shake parameters for the PI controller is established. The database of anti-shake parameters for the PI controller contains several sets of the motor speed and the vehicle target torque VCUTqReq and the corresponding anti-shake proportional coefficient P and anti-shake integral coefficient I of the PI controller. The above data is obtained through several tests, and the anti-shake proportional coefficient P and anti-shake integral coefficient I of the PI controller are obtained based on the actual motor speed MotSpd and the vehicle target torque VCUTqReq.

[0022] A computer-readable storage medium stores a computer program, and when the computer program is executed by a computer, the method as described above is implemented.

[0023] A computer program product includes a computer program, and when the computer program is executed by a computer, the method as described above is implemented.

[0024] Method for correcting anti-slip torque, specifically:

[0025]

[0026] Method for correcting anti-shake torque, specifically:

[0027]

[0028] Wherein the cut-off frequency of the low-pass filter and the cut-off frequency of the high-pass filter are specifically determined by calibration, interp2 is a two-dimensional look-up table function, and abs is an absolute value function.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the technical solutions. Those of ordinary skill in the art should understand that any modifications or equivalent replacements made to the technical solutions of the present invention without departing from the purpose and scope of the present technical solution shall be covered by the scope of the claims of the present invention.

Claims

1. A control method for preventing wheel skidding of a new energy vehicle, characterized in that: Process the automotive CAN signals to parse the vehicle target torque VCUTqReq, the actual motor speed MotSpd, the driving left wheel speed LeftWheelSpd, and the driving right wheel speed RightWheelSpd; Based on the actual motor speed MotSpd, the driving left wheel speed LeftWheelSpd, and the driving right wheel speed RightWheelSpd, calculate the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff, and use the absolute value of the wheel speed difference WhlSpdDiff as the input of the PI controller to output the anti-slip torque AntiSlipTq using the PI controller; Establish a torque correction database, where there are several groups of the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff and the corresponding anti-slip torque correction factor AntiSlipFactor in the torque correction database. The corresponding anti-slip torque correction factor AntiSlipFactor can be obtained through the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff in the torque correction database. Based on the obtained anti-slip torque correction factor AntiSlipFactor, correct the anti-slip torque AntiSlipTq, and accumulate the vehicle target torque VCUTqReq and the corrected anti-slip torque ReAntiSlipTq to obtain the motor torque loop target torque TqLoopTrq.

2. The control method for preventing wheel skidding of a new energy vehicle according to claim 1, wherein: Establish a PI controller anti-slip parameter database, where there are several groups of the absolute value of the wheel speed difference WhlSpdDiff and the corresponding anti-slip proportional coefficient P and anti-slip integral coefficient I of the PI controller in the PI controller anti-slip parameter database. Obtain the anti-slip proportional coefficient P and anti-slip integral coefficient I of the PI controller based on the absolute value of the wheel speed difference WhlSpdDiff.

3. The control method for preventing wheel skidding of new energy vehicles according to claim 1, characterized in that: Use a high-pass filter HPF to filter out the low-frequency interference signals of the actual motor speed MotSpd, use a low-pass filter LPF to suppress the high-frequency noise of the actual motor speed MotSpd, and obtain the effective fluctuation signal of the actual motor speed MotSpd through the combination of the high-pass filter HPF and the low-pass filter LPF.

4. The control method for preventing wheel skidding of a new energy vehicle according to claim 1, characterized in that: The actual motor speed MotSpd is used as the input of the PI controller. The PI controller outputs the anti-shake torque MotDampTq. In the torque correction database, there are also several sets of the absolute value of the rotational speed fluctuation deltaSpd, the absolute value of the wheel speed difference WhlSpdDiff, and the corresponding anti-shake torque correction factor DampFactor. The corresponding anti-shake torque correction factor DampFactor can be obtained through the absolute value of the rotational speed fluctuation deltaSpd and the absolute value of the wheel speed difference WhlSpdDiff in the torque correction database. Based on the obtained anti-shake torque correction factor DampFactor, the anti-shake torque MotDampTq is corrected. The vehicle target torque VCUTqReq, the corrected anti-slip torque ReAntiSlipTq, and the corrected anti-shake torque ReMotDampTq are accumulated to obtain the motor torque loop target torque TqLoopTrq.

5. The control method for preventing motor operation from shaking in a new energy vehicle according to claim 4, characterized in that: A PI controller anti-shake parameter database is established. In the PI controller anti-shake parameter database, there are several sets of motor speeds, the vehicle target torque VCUTqReq, and the corresponding anti-shake proportionality coefficient P and anti-shake integral coefficient I of the PI controller. The anti-shake proportionality coefficient P and anti-shake integral coefficient I of the PI controller are obtained based on the actual motor speed MotSpd and the vehicle target torque VCUTqReq.

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

7. A computer program product, characterized in that: It includes a computer program, and when the computer program is executed by a computer, it implements the method according to any one of claims 1 to 5.

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