HCCI燃烧应用于实际车辆,面临燃烧闭环控制、动态过程控制及HCCI/SI模式过渡控制等难点问题.本文针对这些问题展开研究,基于GT—power软件建立了四缸HCCI/SI复合模式汽油机模型及轿车动力学模型,采用Simulink软件建立了HCCI/SI复合模式汽油机分层闭环控制器.通过典型驾驶过程以及NEDC循环的仿真,对HCCI/SI发动机闭环控制器的动态控制能力和模式切换控制能力进行了研究,详细考察了HCCUSI复合模式汽油机轿车的燃油经济性的改善效果.仿真结果表明,HCCI/SI复合模式汽油机及其控制器可以实现驾驶过程中HCCI与SI模式的比较平滑的过渡,满足车辆行驶的动力需求,并显示出良好的经济性,在整个NEDC循环中比原机节油12.2%.
There are some problems of HCCI combustion used in the automobile such as closed-loop control of combustion, control of dynamic processes, and control of HCCI/SI mode transition. In this paper, a 4-cylinder HCCI/SI gasoline engine model, a passenger car model and a multilayer closed-loop controller model were established with GT-power and Simulink. The capabilities of control in the dynamic process and the mode transition were investigated, and the closed-loop control strategies of the HCCI/SI engine were evaluated in typical driving processes and NEDC cycles, in order to test the improvement of fuel economy of the HCCI/SI engine. The simulation results show that the HCCI/SI engine can achieve a smooth transition from HCCI mode to SI mode during driving, and meet the requirement of driving performance. Compared with the original engine, the fuel consumed during the whole NEDC cycle reduces by 12.2%.