汽油机电液式可变气门正时系统响应性能仿真与试验

Experiment and Simulation on Response Performance of Electro-hydraulic VVT System for Gasoline Engine

摘要:

汽油机电液式可变气门正时系统(VVT)的响应性能对发动机燃烧、排放均有重要影响,汽油机瞬态过程中电液式VVT应根据发动机工况快速调整到目标相位，但由于电液VVT的响应性能受到多方面因素的影响，其速度尚有进一步提升的空间。基于试验和仿真分析，对影响电液VVT响应性能的发动机转速、机油温度、机油压力等因素进行了分析，并详细分析了VVT阶跃响应过程各阶段的影响因素，提出了基于MAP查表的VVT前馈控制算法，试验结果表明，该算法能够实现VVT快速响应，同时保证稳定性。

Abstract:

The response performance of electr-hydraulic VVT technology has significant influence on combustion and emission of gasoline engine. Actual valve timing value should be quickly adjusted to target value on transient operation conditions for gasoline engine. Response speed of electro-hydraulic VVT can be further improved since it has constraints for breakthrough. Factors which have influence on the response speed of electr-hydraulic VVT were studied by both experiment and simulation. Step response process was divided into several sub-process and analyzed. Feed forward control algorithm was designed and applied in VVT control. Experiment results showed that the proposed method could achieve rapid response of VVT and assure the stability at the same time.