Antilock Braking Control of Electric Vehicles with Electric Brake

An electric vehicle is driven by electric motors and it has following three remarkable advantages: (1) Motor torque generation is fast and accurate, (2) Motors can be installed in 2 or 4 wheels, and (3) Motor torque can be known precisely. These advantages enable us easily to realize (1) High performance antilock braking systems, and (2) Estimation of road surface condition. The authors proposed an antilock braking control for a one-wheel vehicle model which has an in-wheel motor. Only electric brake is used in the model to simplify the wheel structure. A sliding mode observer is designed to estimate the friction force and the slip velocity from a wheel speed sensor and a motor current sensor. A sliding mode controller is designed to achieve wheel slip control. The control input is motor applied voltage. A dynamic vehicle model is established in Matlab/Simulink to simulate and verify the performance of the proposed antilock braking control.