Comprehensive chassis control strategy of FWIC‐EV based on sliding mode control

Abstract

Four-wheel independent control electric vehicle has possessed tremendous potentials because the enhancement of driving performance and energy savings can be simultaneously carried out by independent and precise driving/braking/steering control. The study has proposed a comprehensive control strategy aiming at all normal conditions, which employs hierarchical architecture to reach the above-mentioned control. In the high-level controller, sliding mode control scheme is developed to figure out total force and yaw moment. In the low-level controller, energy-efficiency optimisation allocation is presented to reduce motor power losses and obtain energy recovery based on motor efficiency map, and then steering angle allocation is conducted to decrease the lateral force so as to reduce power losses caused by the tyre sideslip. Considering insufficient motor braking torque during large deceleration or even larger, the blended brake control strategy with the motor brake and electric hydraulic brake and further anti-skid brake system control via adopting fuzzy logic method are carried out. The torque and pressure are gained to deliver the corresponding actuators model established according to their physical characteristics. Through CarSim-MATLAB/Simulink-AMEsim co-simulation, results suggest that the developed strategy can boost the vehicle manoeuvrability and reduce energy consumption generated by motors and tyre sideslip under all the conventional occasions.