Investigating Mode Switch from SI to HCCI using Early Intake Valve Closing and Negative Valve Overlap

Summary, in English

This study investigates mode switching from spark ignited operation with early intake valve closing to residual gas enhanced HCCI using negative valve overlap on a port-fuel injected light-duty diesel engine. A mode switch is demonstrated at 3.5 bar IMEPnet and 1500 rpm. Valve timings and fuel amount have to be selected carefully prior to the mode switch. During mode transition, IMEPnet deviates by up to 0.5 bar from the set point. The time required to return to the set point as well as the transient behavior of the engine load varies depending on which control structure that is used. Both a model-based controller and a PI control approach were implemented and evaluated in experiments. The controllers were active in HCCI mode. The model-based controller achieved a smoother transition and while using it, the transition could be accomplished within three engine cycles. The initial deviation in load is unacceptable but can most likely be improved with a predictive mode transition model compared to empirically selected mode transition parameters. Changing the fuel injection method to direct injection instead of port injection is another possible improvement.

• Author: Anders Widd; Patrick Borgqvist; Per Tunestål; Rolf Johansson; Bengt Johansson
• Department/s: Department of Automatic Control; Combustion Engines; ELLIIT: the Linköping-Lund initiative on IT and mobile communication
• Publishing year: 2011
• Language: English
• Publication/Series: SAE technical paper series
• Document type: Journal article
• Publisher: Society of Automotive Engineers
• Topic: Control Engineering; Other Mechanical Engineering
• Conference name: 2011 JSAE/SAE International Powertrains, Fuel & Lubricants
• Conference date: 2011-08-30
• Conference place: Kyoto, Japan
• Status: Published
• Project: Competence Centre for Combustion Processes
• Research group: LCCC
• ISBN/ISSN/Other: ISSN: 0148-7191