Physical Modeling and Control of Homogeneous Charge Compression Ignition (HCCI) engines

Due to the possibility of increased efficiency and reduced emissions, homogeneous charge compression ignition (HCCI) is a promising alternative to conventional internal combustion engines. Ignition timing in HCCI is highly sensitive to operating conditions and lacks direct actuation, making it a challenging subject for closed-loop control. This paper presents results on model-based control of ignition timing and work output using a cycle-resolved physical model including cylinder wall temperature dynamics. The model was used to design model predictive controllers for simultaneous control of the ignition timing and the indicated mean effective pressure by varying the inlet valve closing and the intake temperature. The performance of the resulting controller was evaluated in simulation and two possible extensions were developed. An extended controller was validated on a real engine.