Although the linear control theory has a wide range of applicability, some 'nonlinearities' must be taken into account in practice when a control system is designed. One of the most important nonlinearities that should be taken care of is the nonlinearity of actuators. In particular, saturation of an actuator exists practically in all systems and may deteriorate the control system performance if not considered in the design stage.
In this thesis, a predictive control scheme for a plant with saturating actuators is proposed. In the proposed scheme, future plant outputs and control inputs over a long-range horizon are first calculated and then the control input is recalculated by means of limiting the incremental rate of the calculated control inputs when actuator saturation occurs. By using the proposed algorithm, the control input can be obtained which renders the performance of control system better than known conventional optimized controllers. Simulation results are included to show that the proposed control scheme gives the improved performance.
