关键词: 道路坡度, 车辆载重, 纯电动物流车, 三挡变速系统, 综合性能换挡规律

Abstract: In order to improve the adaptability of the PELV to the dynamic driving conditions, a comprehensive gear shift schedule for three-speed powertrain was proposed with the consideration of road gradient and vehicle loads, as well as dynamic and economic performance of the vehicles. The influences of road gradients and vehicle loads on vehicle’s moment of resistance were analyzed. The dynamic and economic shift schedule with dynamic adaptability were established. Then an optimization model of comprehensive shift schedule under different driving conditions was formulated to take the minimum acceleration time of 0~50km/h and minimum energy consumption as optimization objectives, which was solved via a hierarchical gravitational search algorithm. With the proposed optimization model and algorithm, the comprehensive gear shift schedule was obtained. Finally, MATLAB/Simulink simulation platform was used for comparative analysis of three shift schedule. The results show that the energy consumption per kilometer of comprehensive gear shift schedule is close to economic shift schedule under CHTC-LT driving cycle and has better dynamic performance. Moreover, the comprehensive gear shift schedule eliminates the shifting cycle under different road gradients and vehicle loads, which shows great adaptability to driving conditions.

Key words: road gradient, vehicle load, pure electric logistic vehicle (PELV), three-speed powertrain, comprehensive gear shift schedule