Fuzzy adaptive control of a variable geometry turbocharged diesel engine

Abstract

A fuzzy control approach for the adjustment of the boost pressure of a variable geometry, turbine (VGT) supercharged diesel engine is proposed. The VGT adapts the boost pressure to the target reference for different engine speeds by adjusting the turbine blades, resulting in a reduction of both fuel consumption and gas emissions, while preserving efficiency. We design an adaptive fuzzy control law according to the following steps: first, a standard PI controller is devised, then an equivalent fuzzy controller is built, finally the fuzzy controller is made nonlinear by tuning its input/output parameters using an optimization algorithm. Further, modification of the membership functions is investigated. A large number of simulations on a zero-dimensional model of the engine prove the effectiveness of the proposed control strategy with reference to stability and transient performance in comparison with standard PI techniques.