Research On Matching Design And Control Strategy Of Power System Of A Pure Electric Light Bus

With the increasingly severe energy and environmental issues,efficient and clean pure electric vehicles are attracting more and more attention.The technical core of pure electric vehicle is power transmission system and control system.In this paper,the power system and drive control strategy of pure electric vehicle were studied.Through the structural analysis of the power system of pure electric vehicle,the structure selection of the power system was determined.According to the performance index of the vehicle,the component parameters of the power system were calculated,and the simulation model of the vehicle was built in Cruise for verification.The power system parameters were optimized with multiple objectives.The response surface model was established and the transmission ratio was optimized by non-dominant sorting genetic algorithm(NSGA-II).The optimization target is range and 100km/h acceleration time,and the vehicle performance before and after optimization was compared.The drive control strategy was formulated according to the power transmission system,which includes driving condition identification,torque demand analysis and auxiliary ramp control system for ramp starting condition.An optimal torque control strategy based on fuzzy control is proposed to solve the problem of insufficient power in ramp running of pure electric vehicles.Matlab/Simulink simulation model was established for simulation analysis.The results show that the optimal torque control strategy can effectively identify the driver’s driving intention and improve the dynamic performance and economy of the vehicle.Finally,the simulation model of vehicle hardware in loop(HIL)test was built and the HIL test of the drive control strategy was performed to verify the performance of the vehicle.The results show that the vehicle’s acceleration performance,climbing performance,and cruising range all meet the design indicators.It is shown that the drive control strategy formulated is reasonable and effective,which can meet the requirements of vehicle dynamic economy.