Research On Key Control Technology Of Electric Drive System In Pure Electric Urban Logistics Vehicle

With environmental pollution and energy crisis increasingly serious,pure electric vehicles with high efficiency,low energy consumption and zero emissions are gradually being valued at home and abroad and have become the development trend of the automobile industry.The control technology of the electric drive system is one of the key technologies of electric vehicles,and the quality of the control technology has a direct impact on the vehicle performance.In this paper,the pure electric logistics vehicle equipped with a two-speed automated manual transmission was taken as the research object.And the drive control strategy,braking energy recovery control strategy and shift process control strategy of the pure electric logistics vehicle were emphatically studied.The main content are as follows:(1)The key parameters of powertrain system were matched.According to basic parameters and vehicle performance requirements,the key parameters of the powertrain system were matched,including drive motor power,torque,speed,transmission ratio,battery capacity.And the vehicle parameter model built in AVL Cruise soft was used to verify whether the matching results meet the vehicle basic requirements.(2)Research on drive control strategy.The conventional drive control strategy was analyzed.The influence of accelerator pedal opening change rate on output torque was considered,and the compensation torque drive control strategy based on fuzzy control algorithm was developed on the basis of linear pedal control strategy.(3)Research on braking energy recovery control strategy.The typical braking energy recovery control strategy was analyzed.Combined with the structural characteristics of the braking system of the electric logistics vehicle,the regenerative braking force of the drive motor was determined based on the ideal braking force distribution curve,and the optimal parallel braking energy recovery control strategy was formulated.(4)Research on shifting process control strategy.The dynamic model of the transmission system was established,and the various stages of the shifting process was analyzed according to the model.Considering the limitation of shifting impact on the torque adjusting rate of the driving motor,the control strategy of shifting process was developed,which could realize cooperative control of the driving motor and the shifting actuator.(5)Simulation and test verification.It was verified that the compensation torque control strategy based on fuzzy control algorithm could enhance the acceleration performance,and the optimal parallel braking energy recovery control strategy could improve braking energy recovery efficiency by the co-simulation of MATLAB/SIMULINK and AVL CRUISE.And the good quality of the shifting process control strategy was verified by road tests of the real vehicle.