Computation of parameter dependent robust invariant sets for LPV models with guaranteed performance. (May 2023)

• Record Type: Journal Article
• Authors: Gupta, Ankit; Mejari, Manas; Falcone, Paolo; Piga, Dario
• Is Part Of: Automatica. Volume 151(2023)
• Publication Date: 2023-05
• Subjects: Linear matrix inequality -- Invariant set -- Semi-definite program -- Linear parameter-varying systems; Automatic control -- Periodicals; Automation -- Periodicals; 629.805
• DOI: 10.1016/j.automatica.2023.110920
• Languages: English
• ISSNs: 0005-1098

Abstract

Abstract: This paper presents an iterative algorithm to compute a Robust Control Invariant (RCI) set, along with an invariance-inducing control law, for Linear Parameter-Varying (LPV) systems. As real-time measurements of the scheduling parameters are typically available, we allow the RCI set description and the invariance-inducing controller to be scheduling parameter dependent. Thus, the considered formulation leads to parameter-dependent conditions for the set invariance, which are replaced by sufficient Linear Matrix Inequalities (LMIs) via Polya's relaxation. These LMI conditions are then combined with a novel volume maximization approach in a Semidefinite Programming (SDP) problem, which aims at computing the desirably large RCI set. Besides ensuring invariance, it is also possible to guarantee performance within the RCI set by imposing a chosen quadratic performance level as an additional constraint in the SDP problem. Using numerical examples, we show that the presented iterative algorithm can generate RCI sets for large parameter variations where commonly used robust approaches fail.