Closed Loop Control of Spark Advance Using a Cylinder Pressure Sensor

The objective of the spark advance control technique discussed in this paper is to provide a schedule which is optimum in the presence of changing engine and environmental conditions. The paper shows the benefits of adaptable spark control, describes the ability of a cylinder pressure based system to adapt to optimum spark on a single cylinder laboratory engine and describes the transient performance of a controller mechanized in the laboratory. Averaged over the entire engine speed-load operating regime, the closed loop system yields average brake horsepower within 0.1 percent of optimum based solely on the cylinder pressure information. The system has demonstrated a transient settling time of 0.1 second.