Mode Transition Coordination Control for PHEV Based on Cascade Predictive Method

Abstract

In terms of parallel hybrid electric vehicles (PHEVs), adverse effects resulting from jerk and clutch frictional loss during mode transition operating could damage the ride comfort of passengers and clutch lifespan. To tackle these issues, a coordination control strategy based on cascade predictive control method is presented in this paper. Firstly, dynamic models of PHEV during different mode transition periods are discussed based on characteristics of power sources and clutch states. Secondly, based on the proposed transition models at different stages, model predictive control is considered based on multi-constraints including jerk restriction and physical constraints of dynamic components aiming to reduce the vehicle jerk and clutch frictional loss. Thirdly, in order to realize an accurate and fast response to engine torque, a cascade PID-based controller with high sampling frequency is employed to compensate the engine torque, and further to achieve a smooth mode transition process. Finally, the proposed control strategy is simulated and verified by co-simulation with Matlab/Simulink and Cruise, whose results show that the proposed methods can reduce the vehicle jerk and clutch frictional loss effectively.

Keywords

• PHEV
• mode transition
• cascade predictive control
• vehicle jerk
• clutch frictional loss