Continuous gain scheduled h-infinity observer for uncertain nonlinear system with time-delay and actuator saturation

Abstract

In this paper, we propose a method for designing continuous gain scheduled H-infinity observer for uncertain nonlinear continuous stirred-tank reactor system subject to time-delay and actuator saturation. Initially, gradient linearization procedure is applied to describe such nonlinear system into several linear systems. Next, a convex hull set is investigated in order to transform the actuator constraints into several linear constraints, and then, a set of H-infinity observers is designed for these linear models, which guarantees the system states belong to an ellipsoid invariant set. Finally, continuous gain-scheduled approach is employed to design continuous nonlinear observer on the entire uncertain nonlinear system. A simulation example is given to illustrate the effectiveness of developed techniques. © 2012.