Integrated vehicle dynamics control for energy recuperation in fully electric vehicles

In most fully electric vehicles a regenerative braking system is exploited to extend the vehicle’s driving range. With the electric motor generally present at the front axle, delivering the demanded braking solely through regenerative braking can impose stability issues on the vehicle. This is particularly true for extreme braking conditions such as braking on split-μ surface or braking while cornering on slippery surface. Maximizing recuperated energy and preserving vehicle stability are thus conflicting objectives. A model predictive controller is proposed to coordinate the relationship between the regenerative braking system and the friction brakes in order to find the optimal compromise. The control objective is to maximize the regenerative braking while delivering the requested braking force, preserving stability and satisfying all system constraints. The suggested approaches prove to adequately balance the regenerative and friction braking forces so as to fulfil the control objective.