Higher order sliding mode based control scheme for air path of diesel engine

Abstract

This paper proposes a Higher Order Sliding Mode (HOSM) based control algorithm for air intake circuit of diesel engine. The current diesel engine is a complex system that has mechanisms like Variable Geometry Turbo charger (VGT), Exhaust Gas Recirculation (EGR) to limit the amount of exhaust emissions. Since both VGT and EGR flows are driven by the exhaust gases, there is a strong coupling between them. A nonlinear reduced order model is used for coordinated control development for VGT and EGR actuators. The proposed scheme uses Supertwisting algorithm which ensures robustness against the modeling errors and parameteric uncertainities and at the same time reducing the high frequency chattering. Simulation results have been shown on a validated full order diesel engine model to illustrate the efficacy of the scheme.