Stability Control Using Adaptive Integral SMC Applicable to Variable Speed EV

This paper presents an Adaptive Sliding Mode Controller (ASMC) for enhancing stability in four-wheel independent drive electric vehicles (4WID EVs) under variable-speed conditions. The vehicle model includes key dynamic parameters like cornering stiffness, longitudinal tyre forces, velocity, steering angles, and moment of inertia. The controller aims to maintain stability during uncertainties, such as actuator failure in one wheel, by dynamically adjusting the remaining wheels to keep the vehicle stable. Slip angle (SA) and yaw rate (YR) are critical control parameters, with adaptive proportional-integral (PI) sliding surfaces utilized to modify the control strategy through equivalent and switching controls. The proposed ASMC is compared with PID and Conventional Sliding Mode Control (CSMC) methods. Matlab-based simulations validate the approach, using the Integral Absolute Error (IAE) as a metric for evaluating control accuracy. Results show that ASMC outperforms other methods in managing uncertainties and ensuring vehicle stability.