基于模型预测控制的混合动力汽车模式切换中的转矩协调控制策略

Hybrid electric vehicle (HEV) has multiple working modes and due to the features of system discontinuity, the problems such as poor smoothness arise during mode switching. Accordingly, taking dual-mode series-parallel electromechanical compound transmission system as object, with improving mode switching quality as objective, the control strategy for clutch engagement process is emphatically studied in this paper. Firstly, the overall structure and characteristics of electromechanical compound transmission are analyzed, and the equivalent model for power coupling system is established. Then, a model predictive control-based control strategy for torque coordination is proposed with reducing vehicle jerk and the sliding-friction work of clutch as objective. Finally, the torque coordinated control strategy is verified with simulation model. The results indicate that with the mode switching control strategy proposed, the electromechanical compound transmission system can effectively reduce the torque ripple of output shaft and vehicle jerk, decrease the sliding friction loss of clutch, and hence greatly improve the quality of mode switching, while ensuring faster response of mode switching, having a certain reference value for engineering practice.