Abstract：A two-speed, automatic mechanical transmission (AMT) is developed for electric vehicles with a planetary gear system, a centrifugal clutch and a belt brake. The transmission shifts seamlessly between the two gears to eliminate the power interruption problem during gear shifting in conventional AMT. The electric vehicle driveline is modeled to get the optimal control method using dynamic programming and convex optimization. The optimal control variables and optimal control system minimize vehicle jerk and frictional losses. A normal sectional control method is also used during gear shifting for comparison in simulations. The simulations indicate that the optimal control method significantly improves the gear shift comfort while maintaining the dynamic performance as well as vehicle acceleration with decreases of frictional losses in the clutch and brake.
方圣楠, 宋健, 宋海军, 台玉琢, TRUONG Sinh Nguyen. 基于最优控制理论的电动汽车机械式自动变速器换档控制[J]. 清华大学学报（自然科学版）, 2016, 56(6): 580-586.
FANG Shengnan, SONG Jian, SONG Haijun, TAI Yuzhuo, TRUONG Sinh Nguyen. Shifting control of automatic mechanical transmissions for electric vehicles based on optimal control theory. Journal of Tsinghua University(Science and Technology), 2016, 56(6): 580-586.
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2016, Vol. 56 
