Research On Efficient Regenerative Braking And Anti-lock Braking Control For Electric-wheel Vehicle

Regenerative Braking is a unique technology of Electric Vehicle(EV). It can recycle the kinetic energy and increase the travel distance of EV significantly. Electric-wheel Vehicle, which has the advantages of low noise, no pollution, high-efficiency energy conversion and high precision torque control, become a hot area of the research of vehicle. The current regenerative braking technology research almost focused on hybrid or two-wheel drive EV. However, the research of Electric-wheel Vehicle is very little. Therefore, research of regenerative braking system for Electric-wheel Vehicle has important practical and theoretical significance. This paper is dedicated to how to recycle baking energy efficient, assign relations between the friction brake and the regenerative braking reasonable and prevent wheels from locking in braking process of electric-wheel vehicle. The main research contents is as follows:1. In this paper, based on the structure difference of the Electric-wheel Vehicle and the ordinary EV or hybrid EV, regenerative braking system for electric vehicle is presented. Firstly, functional requirements and constraints of regenerative braking system is analyzed. And then, a composite regenerative braking system that suitable for EV driven by in-wheel motors is presented based on the simplification of the original hydraulic brake system. Then the software design project of the system is introduced in this paper.2. According to braking force distribution theory and dynamics analysis of braking process, the front/rear axle braking force distribution for electric-wheel vehicle is still based on β line of the original car. The distribution control strategy of motor braking force and hydraulic braking force was proposed based on fuzzy control theory, whose input variables were brake pedal travel l and battery SOC values, whose output variable was the ratio of motor regeneration baking force to total demand baking force. And then fuzzy controller was designed and fuzzy logic inference rules were made to coordinate and control of their assignment proportion. In this paper, Anti-lock Braking control strategy was also put forward to preventing wheels from locking.3. In this paper, 15 DOF Electric-wheel vehicle, regenerative braking system and hydraulic brake system simulation model were established based on AMESim software. Baking energy regeneration and Anti-lock Braking control strategy simulation model were established based on Matlab/Simulink software. And then braking performance, braking energy recovery and anti-lock braking ability of the composite regenerative braking system were validated and analyzed according to the AMESim-Simulink co-simulation. The simulation results show that the proposed composite regenerative braking system can not only ensure basic braking performance and recycle braking energy efficiently under low, middle or high braking strength condition but also prevent wheels from locking under emergency braking condition no matter road friction coefficient is low, middle or high. It also indicate that the control strategies proposed in this paper have a good feasibility and rationality.