AMT gear shift control strategy for parallel hybrid electric urban buses

Abstract:

To reduce the time of torque gap during gear shift and realize the quick gear shift for hybrid electric urban bus, based on the mass-spring-damping model, the kinematics models of parallel hybrid transmission system are established. To damp driveline oscillation when picking gear neutral, a controller is designed by LQG/LTR theory. And to minimize engine torque pulsation and satisfy the uncertainty of clutch states in variety of hybrid operate mode, an electric machine torque regulator is also designed based on MPC realizing quick synchronization. The above hybrid AMT gear shift control strategies are verified by simulation and road test, and the results show that the gear shift time is limited to 1 second and the jerk is also kept within a reasonable range. The comfort of urban bus is enhanced and the industrialization process of hybrid electric urban bus AMT system is promoted by applying the above gear shift control strategy.