Geometrical characterization of robust predictive control strategies

Abstract

This paper reviews three methodologies: Model Predictive Control (MPC), Robust MPC based on LMIs and Desensitized MPC. These are applied for uncertainty LTI models and the necessary tools are provided for their maximal robust invariant set comparison. In the case of a classic MPC design one can consider an explicit controller for the nominal dynamic model (the close loop system becoming PWA polytopic) and compute its robust invariant set. If this set is not finetly determined, a contractive algorithm can be used to obtain an outer approximation. A certain degree of robustness can be added to such a construction by adjusting the cost function. Such a robustified control law can be compared in terms of maximal invariant set with the MPC schemes based on LMIs on one hand and with the desensitized version of MPC on the other hand.
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