Abstract
A HCCI engine control was investigated for a natural gas co-generation system. A 4-cycle 2-cylinder engine was used for HCCI combustion as a test engine. The HCCI engine operations with the spark ignition were controlled by actuating the throttle valve and the fuel valve at a constant intake temperature using an electric heater. The throttle valve position was controlled due to keeping a constant engine speed. The fuel valve position and the ignition timing were controlled by referring their value maps preserved in the engine control unit for the engine speed and the intake pressure. The system was conventional, but cheaper and simpler than those of previous proposals for HCCI control. The control system was successful for HCCI stable control when the engine load changed from start to the rated power.
