EXPERIMENTAL STUDY ON CLOSE
LOOP CONTROL OF A FULLY
VARIABLE VALVE ACTUATION

ZHOU Nenghui  XIE Hui WANG  Libiao ZHAO Hua  

(State Key Laboratory of Engines, Tianjin University, Tianjin 300072 )

Abstract: In order to study homogeneous charge compression ignition HCCI combustion, a fully variable valve train is developed. It includes four independent variable parameters of both inlet and exhaust variable valve timing & lift. Meanwhile, with the aim of investigating variable valve actuation (VVA) control strategy, a research platform which includes an AC motor, a 16-bit electronic control unit, avhydraulic system and a PC for experiment management is established to simulate engine operation. VVA control strategy is researched and evaluated detailedly for the platform can simulate engine’s operation. After deep experimental investigation of a close loop control strategy for variable valve timing and variable valve lift is achieved. It can adjust the inlet & exhaust valve lift between 0 mm and 9.7 mm continuously. Furthermore, the valve timing can vary within 60° continuously. Experimental results show that the control strategy can control the dynamic process quickly, precisely and stably, which establishes the foundation of improving gasoline engine’s efficiency and controlling HCCI combustion.

Key words: Variable valve actuation  Electronic control unit  Control strategy  Homogeneous charge compression ignition

CLC No: TK413.4 

国家自然科学基金(50476064)和国家重点基础研究规划(2001CB209204)资助项目. Received 20051008, received in revised form  20060301