Research on vehicle starting control based on reflux power condition

Abstract

Based on a detailed introduction of the working principle and starting process of a new power-cycling continuously variable transmission (PCVT), a starting dynamic model of the system is established. According to its special structure and the characteristics of power reflux, pure-throttle and first-gear-clutch starting controls are proposed. Pure-throttle starting control of PCVT can realize accurate throttle control in stages, by using start time and jerk as control objectives and combining them with driver starting intentions. The clutch-starting control takes the jerk, friction work, and starting time as control objectives. Furthermore, its control strategy of the clutch-oil pressure change rate is formulated in stages, combined with driver starting intentions. To achieve the optimal starting performance, an optimization method is proposed, based on the analytic hierarchy process and genetic algorithm. Simulation results show that the two strategies can effectively guarantee the quality of vehicle starting with consideration of driver intentions. After optimization, the starting jerk is effectively reduced by 36.6% in the pure-throttle starting mode and 34.2% in the first-gear-clutch starting mode.