State Feedback Linearizing Control: Application to a Car Engine

Abstract This work is concerned with the improvements which can be brought to a spark ignition engine using a great deal of automatic control. Attention is paid in particular to fast transient phases, by acting simultaneously on the throttle and the electronic fuel injection device. The objective is to guarantee better performances for the regulation of the air/fuel ratio, so as to improve engine efficiency and exhaust emissions during the transient phases. An average dynamic model of the intake part, validated on engine test bench, is first presented. Next, a closed loop control of the average pressure in the intake manifold is developped, which governs the evolution of the air supply by limiting its rate of variation. A feedback linearization technique is used for tracking a chosen model of reference, with closed loop dynamic error compensation. This control of air supply is associated to a predictor in order to compensate for time delays of the injection procedure. Finally, the results obtained by means of simulation are compared with those obtained experimentally from the engine.