Global output feedback regulation of time-varying delay nonlinear systems and application in chemical reactor system

This article focuses on the global output feedback control for a class of time-delay nonlinear systems with multiple uncertainties. The main motivation lies in the question of whether time-varying and unbounded gains are able to dominate the ever-growing system nonlinearities on the hypothesis that the system is perturbed by the unknown parameters. Under the proposed scheme which is derived by entailing both dual gain method and full-order state observer, an output feedback regulator defined on the whole-time horizon is constructed to ensure the existence of the solution of the closed-loop system as well as the asymptotical convergence of the state. The proposed scheme is superior to the existing output feedback strategies, which not only achieves the domination of uncertain growth rates, but also unifies the design of the systems with or without sensor sensitivity to a certain extent. Finally, the validity of the given approach is verified via practical/numerical examples.