Composite nonlinear feedback control for SISO singular systems with input saturation

This paper studies the technique of the composite nonlinear feedback (CNF) control for a class of singular systems with input saturation. The aim of a CNF control law is to improve the transient performance of the closed-loop system such that the closed-loop system has perfect transient performances, e.g., quick response and small/no overshoot. Because of the special features of the singular systems, the classical CNF control technique for normal systems cannot be applied to singular systems directly. To guarantee the impulsive freeness, a pre-linear feedback law is firstly designed to make the singular system impulsive free. Then, a CNF control law is designed based on the slow subsystem of the impulsive free singular system. Furthermore, a deductive result is concluded for non-strictly proper systems. Finally, the design procedure is demonstrated by an illustrative example.