Driving electric vehicles by electric motors can result in many unique advantages for dynamic control of electric vehicles. With the superior fast and accurate torque control performance of electric motors, electric vehicles, in particular, can achieve higher levels of safety and handling performance. A simple, effective and efficient anti-skid control method specified for electric vehicles is proposed in this paper by considering the real-world resistance factors. This method is developed on the basis of sensing and regulating a newly defined parameter, namely the ratio of the drive motor torque to the angular acceleration of the wheels, both of which can be easily obtained for electric motors. The monotonic relationship between the slip ratio and the ratio of the drive motor torque to the angular acceleration of the wheels is proved under both acceleration conditions and deceleration conditions, by considering the real-world resistance factors. The simulations and the experimental results show that the ratio of the drive motor torque to the angular acceleration of the wheels can be efficiently used, instead of the slip ratio, in anti-skid control. The results indicate that electric vehicles can achieve high-performance vehicle motion control with more flexible and simplified configurations by using in-wheel electric motors.
A sliding mode algorithm for antilock braking/traction control of EVs
