The Open Mechanical Engineering Journal

2015, 9 : 351-360
Published online 2015 June 25. DOI: 10.2174/1874155X01509010351
Publisher ID: TOMEJ-9-351

Braking Method of Electric Vehicle Based on Direct Drive Electro- Hydraulic Brake Unit

Xiaoxiang Gong , Siqing Chang , Lichen Jiang and Xiaopan Li
School of Mechanical Engineering, Nanjing University of Science & Technology, China.

ABSTRACT

For the characteristics of full electric propulsion, a novel kind of brake-by-wire unit is designed for electric vehicle to improve braking performance. A comprehensive brake-by-wire system including this unit is set up after its structure and principle are introduced. Then, a multi-layer fuzzy controller is proposed to regulate decelerate and wheel slip rate, and an optimal regenerative strategy is proposed to recover braking energy. At last, the experiment of brake unit is completed to verify that this novel unit is technologically feasible, and an electric vehicle co-simulation model based on MATLAB/Simulink and AMESim is established to prove that this novel unit is able to significantly improve braking performance of electric vehicle. The simulation result shows braking distance and time are shorten by 12.19% and 15.54% respectively compared with conventional ABS system in the same braking condition, and the recovery efficiencies in light and heavy braking are 53% and 28% respectively.

Keywords:

Direct drive electro-hydraulic brake unit, electric vehicle, electromagnetic linear actuator, fuzzy system, regenerative, slip rate.