ANTI-WINDUP SYNTHESIS FOR NONLINEAR DYNAMIC INVERSION CONTROLLERS

An anti-windup compensation method is proposed for a class of constrained nonlinear systems which, in the absence of saturation, are controlled by certain types of nonlinear dynamic inversion controllers. The anti-windup compensation scheme shares a similar architecture to that proposed by the authors in prior work for linear systems subject to saturation constraints. An encouraging aspect of the proposed scheme is that for globally exponentially stable systems, a particularly simple choice of anti-windup compensator exists and, moreover, this could be regarded as a “nonlinear„ internal model control based anti-windup compensator. More generally, a framework for synthesising optimal anti-windup compensators is suggested, based on nonlinear partial differential matrix inequalities. Finally, a simple example illustrates the effectiveness of the scheme.