混合动力汽车模式切换转矩协调策略研究

Study of Torque Coordination Strategy for Hybrid Vehicle Mode Switching

混合动力汽车在运行中有多种模式可以切换,但在切换过程中,电动机和发动机两个动力源结合时由于转矩的不同会产生一定的波动,影响驾乘的舒适感。文中以并联式混合系统为对象,首先进行动力学分析并建立等效模型,然后通过优化的模型预测控制算法策略,主要将其系数矩阵优化,设计以电动机单独驱动的目标转速和跟踪目标转速能力为基础的目标函数,设计约束条件保证其有可行解。最后,通过预测误差进行反馈校正,利用仿真模型对策略进行验证。结果表明,与传统策略相比,在模型预测控制策略协调转矩下,车辆冲击度和离合器的滑磨损失被有效地降低,提升了模式切换的平顺性和驾驶性能。

Hybrid vehicles have multiple modes to switch in operation,but in the switching process,the combination of two power sources,the motor and the engine,the difference in torque may cause certain fluctuations,which affects the driving comfort.This paper takes the parallel hybrid system as the object,firstly performs the dynamics analysis and establishes the equivalent model,then uses the optimized model prediction control algorithm strategy to optimize its coefficient matrix,design the objective function based on the motor driving alone target speed and the ability to track the target speed,and design the constraints to ensure that it has a feasible solution.Finally,the strategy is validated by feedback correction through prediction errors and using simulation models.The results show that,compared with the conventional strategy,the vehicle shock degree and clutch slip wear loss are effectively reduced,the smoothness of mode switching is improved,and the driving performance is enhanced under the coordinated torque of the model prediction control strategy.