Research On Fuzzy Control Of Regenerative Braking For Electric Vehicles

When EV operated in the processing of deceleration or braking,most of the traction energy generated by the motor were consumed by friction,which would lead to the low energy utilization rate of electric vehicle,therefore,the energy utilization had become the research focus of electric vehicle at home and abroad.This paper provided a realization method for the vehicle application of electromechanical compound regenerative braking based on the intensive study of the electromechanical compound regenerative braking of electric vehicles.The paper mainly focused on the optimization of fuzzy controller for electromechanical compound regenerative braking allocation of electric vehicle and the establishment of the simulation model of electromechanical composite braking force distribution for electric vehicle,the braking characteristics of Brushless DC motor also were considered simultaneously.On these bases,the electromechanical compound regenerative brake test bench was built and tested.The details of the work were as follows:Firstly,the structure of the electro hydraulic composite brake system and the current typical electro-hydraulic braking coordination control strategy had been analyzed,and deduced the feedback process of braking energy of electric vehicle and obtained the main factors that affect the regenerative energy of braking.Secondly,on the premise of satisfying the safety braking range of the electric vehicle and the constraint factors that affected the regenerative braking energy,with the large proportion of regenerative braking distribution as the objective function,optimized the fuzzy controller(the vehicle speed V,braking strength Z and the battery SOC as the input,the regenerative braking distribution ratio as the output)by genetic algorithm,and built the simulation model of electromechanical composite braking force distribution for electric vehicle and regenerative braking energy model by MATLAB/Simulink.Through simulation,higher regenerative braking force and recoverable braking energy were obtained.Finally,the main modules of the electromechanical compound regenerative brake would be built to ensure the safety and scalability of the test bench.The control of regenerative braking torque and hydraulic braking torque could be realized on the basis of Lab VIEW;Meanwhile,according to the electromechanical compound feedback braking control strategy proposed in the previous chapter:the voltage control signal of the hydraulic braking torque and the feedback braking torque could be deduced,the mechanical and electrical compound feedback braking experiment would be completed.The experimental platform could fully realize the control of the regenerative braking torque and the hydraulic braking torque,and recover some of the braking energy,verifying the feasibility of the implementation scheme of electromechanical composite feedback braking.