Symbolic analysis of bifurcation in switching power converters : a practical alternative viewpoint of border collision

摘要

In this letter, a symbolic method is proposed for analyzing the bifurcation in switching power converters. This method focuses on the cyclic operation of the system which characterizes its bifurcation behavior. The concept of block switching sequence is introduced, which, in conjunction with the waveform periodicity of the system, can be used to distinguish the various types of bifurcation behavior, e.g. "smooth" period doubling and "nonsmooth" border collision. This concept explicitly exposes the mechanism of border collision from a circuit operational view-point and leads to a direct detection criterion for this global bifurcation. The proposed method is applied, as an illustrative example, to develop two-dimensional bifurcation diagrams for a voltage-mode controlled buck converter.