Matching And Optimization For The Parameters Of Electric Vehicle Powertrain

Due to the lack of oil resources, the traditional vehicle exhaust emissions for atmospheric pollution and human health hazards, electric vehicles become the main researchful object of each company, and the driving range of electric vehicles is an important factor restricting the development of electric vehicles, so matching and optimization of dynamic parameters has become a major research project for developing high index of electric vehicles.This paper takes the electric vehicle power system as object, calculates the peak power of the motor, rated power,the peak speed of the motor, rated speed of the motor according to the maximum speed,the maximum gradeability and the maximum acceleration performance; this paper adds the transmission device due to the limitations of the motor torque range, calculates the minimum transmission ratio based on the maximum speed, calculates the maximum transmission ratio based on maximum gradeability, calculates the number of stalls with formula; calculates the number of battery and battery pack arrangement according to the maximum output power and the driving range.This paper analyses the working principle and characteristics of the motor and builds the model based on CRUISE; analyses the working principle and characteristics of the power battery and establishes the model; studies for the shift schedule of pure electric vehicles, builds the model according to the dynamic shift schedule; studies for the principle of electric vehicle’s regenerative braking, builds model according to the best braking energy recovery; analyses and simulates the electric vehicle power(maximum speed, maximum climbable gradient acceleration time)and economic (each of the100Km of power consumption).This paper designs the optimization variables, the objective functions and the constraints according to the really instance, then makes the optimization calculation with ISIGHT and CRUISE, the results of analysis show that the optimized vehicle economic performance increases8.34%, maximum speed increases17%in comparison with the last one, and acceleration time and the maximum gradeability are decline, but optimized vehicle performance is closer to designed.The result is proved the feasibility of this matching and optimization method.