Decentralized Control of Large-Scale Uncertain Nonlinear Systems by Linear Output Feedback

Abstract

This paper studies the problem of global decentralized control by output feedback for large-scale uncertain systems whose subsystems are interconnected not only by their outputs but also by their unmeasurable states. We show that under a linear growth condition, there is a decentralized output feedback controller rendering the closed-loop system globally exponentially stable. This is accomplished by extending an output feedback domination design that requires only limited information about the nonlinear system. We will apply our design to lower, upper, and non-triangular nonlinear systems. The significance of our results is that we do not need to have prior information about the nonlinearities of the system. Furthermore, we need to only employ a linear observer in combination with a linear controller to stabilize the system. A time-varying output feedback controller is also constructed for use with large-scale systems that have unknown parameters.