Practical active traction control for independent‐wheel‐drive electric vehicle based on slip‐ratio threshold determination

Abstract

The traditional traction control system (TCS) based on hydraulic braking only works when the wheels are slipping, which will cause the problem of slow response to extreme slip. In addition, the TCS of four‐wheel‐independent‐drive electric vehicle (4WIDEV) is often based on road adhesion characteristics identification or optimal slip ratio identification to implement active control, which is difficult to achieve in engineering. Aiming at this problem, a practical active TCS is proposed in this paper. Firstly, according to the wheel slip state of the front and rear axles, the dynamic transfer of torque between axles is realized to maintain the vehicle propulsion power. Second, the adhesion conditions between road and tire are classified, and two sets of target slip ratio thresholds are formulated for high and low adhesion pavement, respectively. Then the current road adhesion coefficient is estimated by using the advantage that the in‐wheel motor torque can be obtained in real‐time. Thirdly, the overall framework of the control strategy is established, the logic threshold control algorithm is adopted for tracking the wheel target slip ratio. Finally, the simulation results show that the proposed active TCS can improve the vehicle power and avoid excessive wheel slipping.

The Electric Traction Motors Balancing for Load Transfer Effects Compensation

“…Regarding the independent tractive axle drive, a practical active traction control system is proposed, according to the wheel slip state of the front and rear axles, and the dynamic transfer of torque between axles is realised to maintain the vehicle propulsion power (Wang et al, 2023). From the papers involved in independent axle driving, it can be mentioned the analysis of Nussupbek et al, (2023), regarding a proposed phenomenon of redistribution of a 4x4 vehicle traction forces, by considering front and rear drive wheels separately as modular ones with reduction of all parameters to equation for each wheel separately.…”