Abstract: In this paper ,the problem of decentralized control is studied for a class of time-varying nonlinear large-scale systems with interconnect-delay , in which both unmatched uncertainties and matched uncertainties are considered by norm bounding functions . Based on the state observer, a delay-independent dynamic output feedback controller is presented to the controlled systems, With the stabilization theory , a sufficient condition for the closed-loop system’s stability is derived. Finally, a numerical example is provided to illustrate the effectiveness of the paper’s result. it not only shows close-loop stability but also illustrate the system are unaffected when uncertainties and delay are present in the subsystems and interconnections.

Key words: nonlinear large-scale systems, decentralized control, dynamic output feedback, state observer, interconnect-delay.