Research On Parameter Design And Shifting Schedule Of Pure Electric Vehicle

Due to environmental pollution and other issues,governments have begun to limit the use of traditional cars,and the internal combustion engine industry has been hit.At the same time,although the performance and cruising range of electric vehicles have reached the level of availability,they still cannot meet the needs of consumers,and the performance of all aspects needs to be further improved.With the advancement of technology,transmission-free electric vehicles have been replaced by multi-speed electric vehicles.The research in this paper is based on a pure electric vehicle development,and the design parameters of the vehicle transmission system are set with the goal of low energy consumption and low cost.Based on this,three different performance-bias shifting rules are formulated.The content is as follows:(1)In order to obtain the most suitable parameter design for the target pure electric vehicle,the energy consumption and cost analysis of the single-speed,two-speed,thirdspeed and more-speed shifting systems are respectively performed to determine the most suitable gear position.An alternative on-board motor database was established,and then the cost of matching each motor in the database to different speed ratios was compared and analyzed to obtain the most economical design.(2)Characterize the current state of the vehicle with the speed of the vehicle,characterize the driver’s intention with the accelerator pedal opening degree,and formulate the optimal dynamic shifting rule of the vehicle power priority and the optimal economic shifting rule of the vehicle economy priority,and according to The actual performance of the vehicle is biased,combined with the optimal dynamic shifting law and the best economic shifting rules to optimize,and finally develop a comprehensive shifting law that meets the driver’s performance bias.(3)Based on the traditional pure electric vehicle slope identification method,optimize its shortcomings and develop a more usable slope identification method;analyze the dynamic calculation parameters in the slope identification process to analyze the possible impact on the recognition results.It is found that the vehicle quality fluctuation will cause the slope recognition result to deviate greatly from the true slope value.A quality correction method is proposed for this problem.The simulation results show that the quality correction greatly improves the accuracy of the slope recognition.