Two global regulators for systems with measurable nonlinearities and unknown sinusoidal disturbances

Abstract

The class of nonlinear observable systems with known output dependent nonlinearities affected by disturbances generated by an unknown linear exosystem is considered. The output feedback set point regulation problem is addressed by adaptively generating the reference input on line when the exosystem is unknown. Two global solutions to this problem are provided, when only an upper bound on the exosystem order is known: the first one is simpler but is restricted to minimum phase systems while the second one can handle non-minimum phase systems as well and identify the exosystem parameters. © 2008 Springer-Verlag.