Backstepping Control with Integral Action Applied to Air-to-Fuel Ratio Control for a Turbocharged Diesel Engine

The problem of controlling the air-to-fuel ratio of a diesel engine by utilizing the potential of a variable geometry turbine is addressed in this paper. The proposed control law is derived from a backstepping procedure and ensures a local optimal performance close to the operating point. Accurate air-to-fuel ratio is important for emission reduction in diesel engines, therefore is integral action included in the control law to mitigate the effects of constant disturbance inputs or parameter (model) errors. The performance is illustrated by an analytical example.