Study On Power System Matching Of Pure Electric City Bus Based On In-wheel Motor

With energy shortage and environmental pollution becoming increasingly prominent,high-efficiency,energy-saving and environmentally-friendly electric vehicle have become the focus of research and development in countries around the world.In order to alleviate the environmental problems of the city,new energy city buses have gradually emerged with the support of the policy.At present,the driving configuration of pure electric city buses is mainly based on centralized driving and wheel-side driving.The distributed drive configuration of the in-wheel motor is less.Compared with the traditional centralized driving pure electric city bus,the city bus driven by the in-wheel motor has many advantages such as high efficiency,comfort,low floor and wide channel,which is the application trend in the future city bus.Therefore,this paper takes the four in-wheel motor-driven city bus as the research object.In view of the problem of lack of endurance and low efficiency of the pure electric city bus,the research on the matching of the pure electric city bus power system based on the in-wheel motor is carried out,aiming at satisfying the power base and improving the economy of the whole bus.Firstly,based on the matching method and theory of electric vehicle power system,with the restriction of power requirement and driving mileage requirement,the total demand parameters of driving motor and power battery are calculated by MATLAB programming matching,and the parameters of four in-wheel motors are allocated and the power battery is selected reasonably.Secondly,the energy-saving mechanism of distributed drive configuration is studied.The dynamic matching research of four in-wheel motors driving power is carried out.The optimal torque distribution control is proposed to realize the flexible deployment of four motors drives according to working conditions.Power,and the development of the corresponding control strategy and the Simulink strategy model;Finally,the simulation software AVL-CRUISE is used to build the whole vehicle model,set the parameters of each component,connect the signal and set the simulation task of the pure electric city bus driven by in-wheel motor,so as to verify the power performance and economic performance of the whole vehicle,and compare the performance with that of the single motor-driven city bus driven by the same power drive system.The simulation results show that(1)The parameters matching of the power system of the pure electric city bus based on in-wheel motor is reasonable and can meet the performance requirements of the design.(2)The optimal efficiency-based torque control allocation strategy for dynamic matching of driving power in this paper can improve the vehicle’s economic performance to a certain extent.The efficiency of CCBC is 4.06% higher than that of average torque allocation,and that of CHTC-B is 5.54% higher than that of average torque allocation.(3)Under the same conditions of power drive system,the efficiency of the matched in-wheel motor drive configuration and single motor drive configuration in CCBC and CHTC-B conditions is increased by 9.38% and 11.7%,respectively.Therefore,the matched in-wheel motor drive pure electric city bus power system in this paper has better energy-saving advantages.