A Hamiltonian viewpoint in the modeling of switching power converters

In this paper we show how, using the Hamiltonian formalism, we can systemat ically derive mathematical models that describe the behaviour of a large cl ass of switching power converters, including the "Boost", "Buck", "Buck-Boo st", "Cuk" and "Flyback" converters. We follow the approach proposed by van der Schaft and Maschke and extract from the basic (energy-conserving) LC-c ircuit the remaining elements, i.e., resistors, switches, diodes and transf ormers, which we treat as external ports. This method naturally yields a Ha miltonian system with two additional conjugated sets of port variables. Thi s procedure, besides being systematic and very general, has the additional advantage of resulting in equations of a form appropriate for simulation an d design of the highly succesful passivity-based controllers. (C) 1999 Else vier Science Ltd. All rights reserved.