H∞control of interconnected nonlinear sampled-data systems with parametric uncertainty

Abstract

This paper studies the problem of robust control design for a class of interconnected uncertain systems under sampled measurements. The class of system under consideration is described by a state space model containing unknown cone bounded nonlinear interaction and time-varying norm-bounded parameter uncertainties in both state and output equations. Our attention is focused on the design of linear dynamic output feedback controllers using sampled measurements. We address the problem of robust H∞ control in which both robust stability and a prescribed H∞ performance are required to be achieved irrespective of the uncertainties and nonlinearities. The H∞ performance measure involves both continuous-time and discrete-time signals. It has been shown that the above problems can be recast into H∞ syntheses for related N decoupled linear sampled-data systems without parameter uncertainties and unknown nonlinearities, which can be solved in terms of Riccati differential equations with finite discrete jumps. A numerical example is given to show the potential of the proposed technique.