Abstract

One of the key issues in control engineering is to find conditions to assure global stability for the operating point. It is usual to assume that such a point is at the origin of the mathematical model representing the real system. After linear models, a more realistic approach is to consider the nonlinearities induced by the saturation of actuators. The analysis of saturated linear systems, even with only one equilibrium at the origin, is far from being completely finished. Recently, it appeared a paper by Moreno and Suárez (Systems & Control Letters 51, 2004, 293-309) where the authors show that stable periodic orbits can coexist with the stable equilibrium at the origin, which represents an warning call for practitioners. The talk is strongly related with the three-dimensional system considered in the paper, and we will show some new aspects of the problem.