Proportional-integral-plus (PIP) control of non-linear systems

A control design procedure is proposed for a large class of discrete-time non-linear systems which combines exact linearization by feedback techniques with an established linear controller design methodology. The combined system thus inherits many of the characteristics of the linear system with regards to tracking, disturbance rejection and robustness. The design both of the linearizing feedback and of the overall linear controller is analyzed and example systems are used to illustrate the design method and demonstrate the performance characteristics of the closed-loop system. Special consideration is given to the effect of the non-linear feedback components on the performance of the controlled system under disturbance conditions and in the case of model mismatch