Experimental evaluation of predictive combustion phasing control in an HCCI engine using fast thermal management and VVA

This paper presents experimental results on model predictive control of the combustion phasing in a Homogeneous Charge Compression Ignition (HCCI) engine. The controllers were based on linearizations of a previously presented physical model of HCCI including cylinder wall temperature dynamics. The control signals were the inlet air temperature and the inlet valve closing. A system for fast thermal management was installed and controlled using mid-ranging control. The resulting control performance was experimentally evaluated in terms of response time and steady-state output variance. For a given operating point, a comparable decrease in steady-state output variance was obtained either by introducing a disturbance model or by changing linearization point. The robustness towards disturbances was investigated as well as the effects of varying the prediction and control horizons.