Fuzzy modelling, control, and bifurcation-based stability analysis of a gasoline direct injection engine

Abstract

This paper presents an advanced model and control structure of a non-linear hybrid system: a gasoline direct injection (GDI) engine. The engine management system proposed in the paper is based on a hierarchical structure that uses Takagi—Sugeno fuzzy models of the engine to define piecewise linear controllers. Thanks to the hierarchical controller structure, engine idle speed regulation is tackled as a high-level requirement and therefore no specific low-level controller is needed. Moreover, the two combustion modes are correctly handled to optimize the engine efficiency. A global stability analysis of the GDI engine working either in homogeneous mode or in stratified mode is also presented, based on bifurcation analysis. Bifurcation analysis can be applied to a wide range of different controllers (even close-to-production), and therefore it can be of significant practical value.