Composite Control Design for In-Wheel Drive Electric Vehicle with Unknown Disturbances and Input Delay

This paper focuses on lateral motion stability con-trol of an in-wheel drive electric vehicle while accounting for un-known external disturbances and input time delay. A predictive sliding mode control using super twisting techniques is designed to mitigate the consequences of input time delay, tracking inac-curacy, and chattering phenomenon. Further, to degrade the lumped disturbances, a disturbance observer (DOB) is empha-sized to estimate unknown disturbances and facilitate feedfor-ward compensation for control. Then, a composite control structure combining predictive super-twisting sliding mode control (STSMC) and DOB is proposed to realize precise tracking uti-lizing appropriate disturbance estimation. To prove the closed-loop stability, a Lyapunov function-based analysis is performed. Simulation is carried out in MATLAB/Simulink to validate the proposed control, and two critical maneuvers are presented to demonstrate its effectiveness.

I. Introduction

Recently, in-wheel drive electric vehicle (IWD-EV) has gained much more attention due to their advantages, such as actuation flexibility, fast response and high efficiency. In addition, it is also feasible to develop an extra yaw moment by controlling the forces (driving or braking forces) at each in-wheel motor [1]. Although IWD-EV is more effective, it is undeniable that fast-moving electric vehicles (EVs) on slippery roads may include phenomena such as flick, sideslip, and sharp turns that are prone to traffic accidents. Therefore, lateral motion stability control of EVs is essential to prevent accidents and ensure vehicle safety. On the other hand, the IWD-EV is an over-actuated system that inherently consists of a non-linear dynamic with solid coupling, leading to a challenging vehicle stability control task [2].