ROBUST CONSTRAINED PREDICTIVE CONTROL OF A MAGNETIC LEVITATION SYSTEM

This paper concerns the implementation of a robust predictive state regulator for a second order nonlinear model of the vertical dynamics in a magnetic levitation system. The predictive control law uses feedback linearization and ensures constraint satisfaction, when external disturbances are present, by tightening the original operational constraints. For comparison, an implementation based on an approximate prediction model obtained by Taylor linearization is also considered. Simulation results show the advantages of using exact feedback linearization, as robust feasibility is not guaranteed when the prediction model is only an approximation of the nonlinear plant.