Control of I.C. Engines for Emissions and Idle Speed Regulation

Abstract

Abstract Presented in this paper is a controller design methodology for simultaneously regulating engine idle speed and air-fuel ratio in the presence of an external non-measurable torque load disturbance. Hammerstein type models are used to characterize the nonlinear dynamics associated with the air and the fuel entrainment process. A feedback and feedforward control approach based on describing functions is used to achieve the performance goal of maintaining the engine idle speed within a prespecified output tolerance while limiting excursions in the air-fuel ratio.