Two Q-ZSCs with Efficient Buck-Boost Gain

Two variant DC-DC q-ZSCs were recently proposed. These converters along with the previously presented four topologies, own buck and boost properties when their duty ratios are varied from 0 to 1. The advantages of these proposed topologies over the existing q-ZSC topologies include continuous gain curve and buck-boost converter gain. This paper found additional advantages of buck-boost capability at the efficient duty ratio range of 0.35 to 0.65 contrary to the buck only or boost only capability for the existing topologies at this duty ratio range. The circuits were analyzed and mathematical relationships derived to arrive at these findings. Operations of these two converters were compared using identical components to further verify the findings. Result of the comparison shows that their gains and operations are identical therefore can be grouped as a class to extend the family of non-isolated DC-DC q-ZSCs from four to six topologies.