Studies of Routes to Chaos for Current-Programmed DC/DC Converters

This paper reports two distinct types of bifurcation paths exhibited by current-programmed dc/dc converters, which are distinguished by the ability or inability to undergo repeated period-doublings. In particular, this paper focuses on the open-loop converters, i.e., ones that do not contain an output feedback loop. It is shown that for the case of the boost converter, the two different types of bifurcation paths can be viewed as part of another bifurcation in which a quasi-periodic sequence transmutes into a period-doubling sequence. For the buck converter, however, period-doubling routes to chaos are found not possible, and in this case, the bifurcation patterns essentially comprise quasi-periodic regions with windows of periodicity. With the range of one bifurcation parameter fixed, the bifurcation diagrams contain more scaled-down replicas, as another bifurcation parameter increases, which are arranged in a manner similar to the period-doubling cascade.