Design of compensators for second order sliding modes

Abstract

In this paper, compensators for the Twisting and Sub-Optimal algorithms are designed. The compensation is aimed at the increase of the open-loop gain of the system with respect to the averaged variables (at low frequencies) achieved through the mechanism of the increase of the equivalent gains kn of the controller nonlinearities. The describing function method is used for the development of the system model. An example of design and simulations are presented.