AMT驱动构型对纯电动客车综合性能影响研究

Influence of Drivetrain Topology Configuration with AMT on Comprehensive Performance of Pure Electric Bus

为研究自动机械式变速器(AMT)驱动构型对纯电动客车综合性能的影响,以12 m电机直驱纯电动城市客车为研究对象,装备3挡AMT并对驱动电机重新选型,利用NSGA-Ⅱ多目标优化算法以0~50 km·h-1加速时间最短和中国典型城市工况(普通道路和快速道路)下行驶能耗最低为目标对变速箱传动比进行优化,并制定基于车速和加速踏板开度的双参数动力性与经济性换挡规律,在中国典型城市工况不同道路下,采用2种换挡规律对整车驱动能耗与制动能量回收进行仿真,并利用最大爬坡度及加速时间对整车动力性能进行分析。研究结果表明:与原电机直驱构型下整车性能相比,AMT驱动构型在将驱动电机峰值转矩降低68.4%后,最大爬坡度从20.07%提高到20.3%,0~50 km·h-1加速时间从14.19 s增加到18.69 s,整车动力性虽满足要求,但加速时间增加了31.7%;其驱动能耗有所降低,但制动能量回收能力有所减弱,且二者都受行驶工况和换挡规律的影响,普通道路行驶时,经济性和动力性换挡规律百公里驱动能耗分别降低了1.55%和0.55%,百公里制动能量回收分别减少了1.35%和1.53%,百公里综合能耗分别降低了-0.12%和1.62%,快速道路行驶时,经济性和动力性换挡规律百公里驱动能耗分别降低4.78%和3.72%,百公里制动能量回收分别减少了1.53%和5.1%,百公里综合能耗分别降低了5.63%和3.35%。可见,纯电动客车采用AMT驱动构型时,需综合考虑车辆设计要求及行驶工况与换挡规律的影响。

In order to study the influence of drivetrain configuration with an automatic mechanical transmission(AMT)on the comprehensive performance of a pure electric bus,a 12 m direct-drive pure electric city bus was taken,equipped with a three-speed AMT and rematched the drive motor.Based on the NSGA-Ⅱmulti-objective optimization algorithm,the gearbox transmission ratio was optimized for the purpose of minimizing the acceleration time of 0 to 50 km·h-1 and the energy consumption of China’s typical urban cycles(normal roads and throughways).Then,the two-parameter dynamic and economic gearshift schedules were formulated based on vehicle ve-locity and accelerator pedal opening.Finally,driving energy consumption and braking energy re-covery simulations were conducted with different gear shift schedules in normal roads and throughways for China’s typical urban cycles.Meanwhile,the dynamic performance was analyzed through the maximum gradeability and acceleration time.From comparison with the direct-drive pure electric bus,it can be shown that when the bus is equipped with an AMT,the maximum gradeability increases from 20.07%to 20.3%,the peak torque of the drive motor decreases by 68.4%,and the acceleration time of 0 to 50 km·h-1 rises from 14.19 s to 18.69 s.Although the dynamic performance of the vehicle can meet the design requirements,the acceleration time in-creased by 31.7%.At the same time,the driving energy consumption decreased but the capacity of the braking energy recovery weakens.Both are affected by the vehicle driving cycles and AMT shift schedules.When driving on normal roads,the driving energy savings can reach 1.55%and 0.55%for 100 kilometers,compared with 4.78%and 3.72%on throughways,using the economic and dynamic gear shift schedule,respectively.However,the braking energy recovery decreased by 1.35%and 1.53%on normal roads and 1.53%and 5.1%on throughways.Thus,the comprehensive energy consumption for 100 kilometers will decrease by-0.12%and 1.62%on normal roads compared with 5.63%and 3.35%on throughways when using the dynamic and economic gear shift schedules,respectively.Therefore,it is necessary to comprehensively consider the influence of vehicle design requirements,driving conditions,and shift schedules when adopting the AMT drivetrain configuration to an electric bus.