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Summary This paper focuses on the synthesis of sampled‐data linear parameter‐varying (LPV) control laws. In particular, the problem of L2 disturbance attenuation for continuous‐time LPV systems under aperiodic sampling is addressed. It is explicitly assumed that the LPV controller is updated only at the sampling instants while the plant parameter can evolve continuously between two sampling instants. The proposed approach is based on a polytopic model for the LPV system and the use of a parameter‐dependent looped‐functional to deal with the aperiodic sampling effects. From these ingredients, conditions in a quasi‐LMI form (ie, they are LMIs provided a scalar parameter is fixed) are derived to compute a stabilizing control law ensuring an upper bound on the closed‐loop system L2‐gain. These conditions are then incorporated to convex optimization problems aiming at either minimizing the L2‐gain upper bound or maximizing the allowable sampling interval for which stability is ensured. Numerical examples illustrate the proposed methodology.

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This paper addresses the problem of tracking periodic references for uncertain linear systems subject to control saturation. Accordingly to the internal model principle, a control loop containing the modes of both the references and additive disturbances is considered. From this structure, conditions in a "quasi" LMI form are proposed to simultaneously compute a stabilizing state feedback gain and an anti-windup gain. Provided that the references and disturbances belong to a certain admissible set, these gains guarantee that the trajectories of the closed-loop system starting in a certain invariant ellipsoidal set contract to the linearity region of the closed-loop system, ensuring therefore the perfect reference tracking. Based on these conditions, an optimization problem aiming at the maximization of the invariant set of admissible states and/or the maximization of the set of admissible references/disturbances is proposed. Numerical examples to illustrate the method are provided.

This paper addresses the problem of tracking and rejection of periodic signals for linear multi-input, multi-output systems subject to control saturation. To ensure the periodic tracking/rejection, a modified state-space repetitive control structure is considered. Conditions in a "quasi" linear matrix inequality form are proposed to simultaneously compute a stabilizing state feedback gain and an anti-windup gain. Provided that the references and disturbances belong to a certain admissible set, these gains guarantee that the trajectories of the closed-loop system starting in a certain ellipsoidal set contract to the linearity region of the closed-loop system, where the presence of the repetitive controller ensures the periodic tracking/rejection.

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