Robust stability analysis of interconnected systems with uncertain time-varying time delays via IQCs

This paper presents a general modeling framework for interconnected LPV systems, that includes model classes like decomposable systems as special cases. The framework allows to consider arbitrary dynamic interconnection operators in the model. We propose to use integral quadratic constraints (IQCs) for robust stability analysis of such interconnected systems and provide convex sufficient conditions for the practically relevant case when communication between subsystems is delayed by an uncertain time-varying time delay. For that purpose, a survey of results on IQCs for time delay operators is presented. When analyzing robust stability, we distinguish between dynamic interconnection in- and output operators of the subsystems and a time-varying real valued interconnection topology, which may be switching arbitrarily fast under certain conditions.