Abstract: Aiming at the problem of lacking climbing ability of a pure electric van in mountainous city road,analyzes the parameters matching method of main components of the dynamic system which affects the vehicle performance.Taking the driving distance and the maximum climbing degree as goals,using DOE orthogonal test method to optimize the transmission ratio.The vehicle model is established and the dynamic simulation results of optimization before and after are compared and analyzed by the Cruise software.The results show that after optimization,the climbing ability of the van is significantly enhanced,and the acceleration performance is also slightly improved.

Key words: pure electric van, transmission system, DOE orthogonal test, optimization