NONLINEAR CONTROL OF A SPARK-IGNITION ENGINE

This paper describes the improvements which can be made to a spark-ign ition engine by extensive use of automatic control. Particular emphasi s is placed on fast transient phases produced by simultaneous action o n the throttle and the electronic fuel injection device. The aim is to achieve better performance for the fuel/air ratio regulation system, thereby improving engine efficiency and exhaust emission during these transient phases, The authors begin by presenting an average dynamic m odel of the intake manifold validated on an engine test bench and goes on to develop a closed-loop system controlling average pressure in th e intake manifold using the reference tracking model method. The air s upply control system is combined with a predictor to compensate for de lays in the injection procedure, The paper concludes with a comparison between the results obtained using simulation and those obtained expe rimentally from the engine.