汽油机缸内直喷(GDI)结合均质压燃(HCCI)燃烧的复合燃烧模式，已成为国际内燃机界的研究热点。为充分发挥直喷技术和均质压燃的综合优势，需要对发动机实施精确的燃烧闭环控制。本项目围绕基于离子电流的发动机燃烧循环内闭环控制展开，深入研究GDI发动机在火花点火和压燃燃烧模式下不同典型工况的离子电流特性及其影响因素，结合化学反应路径模拟分析离子电流生成机理及规律，揭示离子电流特征与缸内燃烧信息的内在联系及影响规律，基于DSP设计并优化离子电流信号实时检测及反馈控制系统。以燃烧和排放特性优化为目标，针对GDI发动机冷起动、暖机工况、HCCI燃烧模式瞬态工况以及SI/HCCI模式切换过程开展研究，实现基于离子电流的燃烧循环内闭环控制，可靠应用于失火循环检测与控制、当前失火循环内的补火或补油补火控制、循环间的燃烧与排放控制策略及优化，以及SI/HCCI模式切换过程闭环控制。

Gasoline Direct Injection engine combined with HCCI combustion mode has become a research focus for internal combustion engine all around the world. To effectively extend the comprehensive advantages of direct injection technology and HCCI, it is necessary to implement a precise combustion closed loop control on the engine. This project focus on the closed loop technologies in combustion cycle based on ion current, investigate the ion current characteristics under different typical working conditions at both spark-ignition and compression-ignition combustion modes, as well as its influencing factors. Ion current formation mechanism and its laws will be revealed with the chemical reaction path simulation method, and the relationship between the ion current characteristics and in cylinder combustion information will be explored. An ion current signal real-time detection and feedback control system based on DSP will be designed and optimized. Aim at combustion and emission characteristics optimization, researches will be carried out on cold start and warm up conditions in SI mode, transient operating conditions in HCCI combustion mode, and the SI/HCCI mode transfer process on GDI engine. the in-combustion-cycle closed loop control strategies based on the ion current. Furthermore, reliably apply these strategies to the detection and control of misfire combustion cycle, the control of strategy of re-spark ignition w/o re-injection within current misfire combustion cycle, the control and optimization of cycle by cycle combustion and emission characteristics, as well as the control strategy of SI/HCCI mode transfer process.