Robust stability analysis of MIMO systems with asymmetric nonlinearities

Abstract

The aim of this paper is to study the existence of limit cycles and undesirable equilibrium points in nonlinear, MIMO control systems in the presence of uncertainties. This study is important from the engineering point of view because such limit cycles and equilibria may change the global behaviour of the system, e.g. global stability may be lost. The analysis is performed using the describing function method. This paper extend the results of previous work to the case of asymmetric nonlinearities with the use of the dual describing function. The method is illustrated by means of an example.