An adaptive sliding mode controller for air-fuel ratio control of spark ignition engines

Abstract

An adaptive dynamic sliding mode fuel injection control algorithm based on the measurement of a binary oxygen sensor to reduce the exhaust gas emissions is proposed. The controller suggested in this paper is designed on the basis of the two-state dynamic engine model developed in the crank angle domain, and it is composed of an adaptation law for fuel delivery model parameters and measurement bias in mass air flowrate. The control algorithm is mathematically compact enough to run in real time, and it is robust to modelling errors as well as to rapidly changing manoeuvres of the throttle. The simulation and experimental results show that this algorithm can substantially reduce the transient peaks in air-fuel ratio (AFR) while maintaining robustness to model errors and measurement delay.