Effect of gear shift and engine start losses on energy management strategies for hybrid electric vehicles

摘要

In this study, the energetic loss models involved with gear shift and engine start in a parallel passenger hybrid electric vehicle (HEV) will be introduced, and their effects on energy management strategies will be analysed. The simulation results disclose a superior fuel efficient property of the powershift-automated manual transmission (PS-AMT) HEV over the AMT one. However, by reducing the interruption time in the gear shift process of the AMT as much as possible, its fuel deficiency, when compared to the PSAMT, can be reduced noticeably. Furthermore, with an assumption of given preview route information, a model predictive control (MPC) algorithm is applied to investigate an achievable fuel saving with respect to the prediction horizon. It reveals a minimum prediction horizon of 5 s is required for the MPC-based controller to get the possible maximum fuel economy under the impact of the engine start loss.