缸内直喷式汽油机冷起动控制策略

根据直喷式汽油机(GDI)冷起动的特性和冷起动的基本要求,设计了相应的冷起动控制策略。以前期自主设计的ECU电控系统和试验台架为基础,编写了冷起动控制策略程序,搭建了GDI发动机冷起动试验平台,进行了发动机冷起动控制策略试验研究。结果表明:按照冷起动各阶段的最优参数控制策略起动发动机,3个循环即可起动成功。发动机转速在1 023 r/min上下波动,转速波动率为6%,催化剂的起燃时间为38 s,起燃较快,且HC排放量较低,满足发动机冷起动过程的总体要求。

Cold Start Control Strategy of Gasoline Direct Injection Engine

The control strategy, on the basis of features and demands of cold start conditions, was developed and illustrated thoroughly. The experimental platform was built up and the program of the cold start control strategy was written based on the preliminary work of electronic control system and test bench, and the research on cold start was made. The results show that the engine starts by three cycles successfully with the optimal control parameters for each stage to control cold start process. The engine speed fluctuated around 1023r/min and the speed fluctuation rate was only 6%. The light-off time of the catalyst was 38s and HC emission was at lower lever. The control strategy can meet the general demands for GDI engine cold start.