功率分流式混合动力系统发动机起动平顺性控制研究

Engine Start Control Study of Power-split Hybrid Electrical System

为改善功率分流式混合动力系统纯电动至混合动力模式切换性能设计了一套控制算法。通过发动机曲轴位置和拖转扭矩预估行星架输入端的阻力,在转矩分配时将该扭矩作为输入条件,从而消除因发动机拖转扭矩波动导致的整车抖动;根据整车动力学模型设计状态观测器,以输出轴转速和轮边转速之差为反馈进行闭环控制,以减少输出轴转速波动。通过模型仿真和实车试验对该控制算法的有效性进行验证。

In order to improve the switching performance from electric mode to hybrid mode in power-split hybrid system, a control algorithm was designed. Planetary carrier input end resistance was estimated according to engine crankshaft position and dragging torque, which was used as input condition in torque distribution, thus eliminating vehicle trembling caused by engine dragging torque fluctuation; according to vehicle dynamic model design state observer, the difference between output shaft speed and wheel speed was used as feedback for closed-loop control, thus to reduce output shaft speed fluctuation. Validity of this control algorithm was verified through model simulation and vehicle test.