NONLINEAR MULTIVARIABLE ROBUST INTERNAL MODEL CONTROL OF A TWO-STAGE TURBOCHARGED DIESEL ENGINE

This paper proposes a new approach to the design of Internal Model Controllers (IMC) for nonlinear systems with emphasis on robustness issues. A nonlinear IMC controller is used which is based on the right inverse of the plant model. As the right inverse is, in general, not realisable, it is combined with a linear filter. The right inverse is constructed using nonlinear geometric control methods for input-affine systems. Robust stability of the closed-loop is investigated for unstructured (multivariable) output uncertainties.The industrial feasibility of the controller and the robustness analysis is shown for the nonlinear IMC control loop of a two-stage turbocharged diesel engine.