Nonlinear feedback switching rule design for sector-bounded switched systems

This article presents a robust switching rule design technique for a class of nonlinear and uncertain switched systems. The approach is based on a state transformation that allows for nonlinear state feedback. The results are given in terms of linear matrix inequality problems and they guarantee global asymptotic stability of the closed-loop system even if sliding modes occur on any switching surface. The class of systems considered is general enough to include multiple time varying sector-bounded nonlinearities associated with real-time changes in the operation point. The potential of the method is illustrated through photovoltaic systems, in which the nonlinear I-V characteristic of the modules is treated as a sector-bounded function. As the slope of the sectors depend on the environmental conditions, robust sectors containing the nonlinearities for any uncertain uniform operation condition are derived.