Dynamical effects of missed switching in current-mode controlled DC-DC converters

Abstract

Past investigations on nonlinear phenomena in DC-DC converters assume ideal switching and ignore the practical issue of switching ripples, for which the sampled data models yield piecewise smooth but continuous maps. In this brief, we show that the unavoidable nonidealities in the switching result in discontinuity in the map, which drastically changes the bifurcation structures. We demonstrate these effects experimentally, and develop simple one-dimensional models that account for switching delay and transients, and can predict the bifurcations in such systems with reasonable accuracy. Using the recent developments in bifurcation theory, we derive the limiting conditions for a reliable period-1 operation when these effects are considered.