Abstract: Electric vehicles use conventional friction braking and the regenerative braking of drive motor to achieve antilock braking. In this paper, the advantages and disadvantages of antilock braking system (ABS) are analyzed, and an antilock control system based on PI control is proposed and then verified by real vehicle test. Three different structural configurations for ABS are designed: hydraulic ABS alone, regenerative ABS in front axle only and hydraulic and regenerative ABS in front axle and hydraulic ABS in rear axle, with their braking performances evaluated. Hydraulic ABS is based on rule controllers, while continuous regenerative ABS controls slip ratio through target gain, proportional integral and feedforward/feedback controllers. The results of test on lowadhesion road show that regenerative ABS can accurately track the ideal curve of wheel slip ratio in braking process, reduce the frequency of vehicle body vibration and improve the ride comfort of vehicles.

Key words: EV, ABS, continuous antilock braking, ABS braking rules