Identification and idle speed control of internal combustion engines

This paper presents an integrated approach for the identification and control of internal combustion engines in idle-speed conditions. The inputs of the nonlinear identification model are the position of the idle speed air actuation system and the spark advance, while its outputs are the pressure inside the air intake manifold and the crank shaft speed. The estimated model is then used to synthesize an idle speed controller with the linear quadratic technique. The design procedure outlined here is currently being used by Magneti Marelli for the synthesis of commercial idle-speed regulators. Some identification and control results obtained by applying this method to a 1400 cm3 commercial engine are reported to witness the effectiveness of the proposed approach.