Closed-loop Combustion Control of Homogeneous Charge Compression Ignition (HCCI) Engine Dynamics

Summary, in English

Homogeneous charge compression ignition (HCCI) is a hybrid of the sparkignition and compression ignition engine concepts. As in a sparkignition engine, a homogeneous fuel-air mixture is created in theinlet system. During the compression stroke the temperature of themixture increases and reaches the point of auto ignition, just as in acompression ignition engine (or Diesel). One challenge with HCCI engines isthe need for good timing control of the combustion. Auto ignition of ahomogeneous mixture is very sensitive to operating condition. Evensmall variations of the load can change the timing from too early totoo late combustion. Thus a fast combustion timing control isnecessary since it sets the performance limitation of the loadcontrol. As measurement for combustion timing feedback, the crank angleof 50% burnt has been used. This paper performs a comparative studyof different cylinder-pressure based methods for estimating the crankangle of 50% burnt. The estimates are compared in terms of accuracy,robustness and feasibility for cycle-to-cycle real-time control.Dynamic models of CA50 are estimated using system identification asa means to find models relevant to engine control.

• Author: Johan Bengtsson; Petter Strandh; Rolf Johansson; Per Tunestål; Bengt Johansson
• Department/s: Department of Automatic Control; Combustion Engines
• Publishing year: 2004
• Language: English
• Pages: 167-179
• Publication/Series: International Journal of Adaptive Control and Signal Processing
• Volume: 18
• Issue: 2
• Links: http://dx.doi.org/10.1002/acs.788
• Document type: Journal article
• Publisher: John Wiley & Sons Inc.
• Topic: Other Mechanical Engineering; Control Engineering
• Keywords: closed-loop combustion control; HCCI; combustion engine; subspace-based identification
• Status: Published
• Project: HCCI Control
• ISBN/ISSN/Other: ISSN: 0890-6327