Modelling and Control of DC-DC Switching Converters: A Tutorial Perspective

Basic concepts of modelling and control of DC-to-DC switching converters are presented in a tutorial approach. After defining Power Electronics and its application domain, DC-DC switching conversion is presented as the basic core of the domain, and power converters are classified as variable structure systems. The notion of switching regulator is subsequently introduced and the operation of a pulse width modulator is described to eventually derive a continuous-time model from the averaged converter dynamics. Using the converter continuous-time model, a dynamic model of the switching regulator is obtained and both one-loop and cascaded linear controllers are described. Non-linear control of switching converters is studied through the induction of sliding regimes in power converters. Equivalences between sliding systems and those employing a pulse width modulator are established and some applications are described. Finally, a compilation of techniques for the non-linear dynamics analysis in switching converters is introduced by means of a generalized description based on a discrete-time model that predicts the resulting bifurcations and allows controlling the chaos. Copyright (C) 2009 CEA.