부산대학교 도서관

This paper proposes a zero-voltage-switching (ZVS) Buck/Boost converter (BBC). In addition, an auxiliary circuit based on a coupled inductor is introduced to realize ZVS for the main MOSFETs. The magnetic coupling inductor plays the role of filtering and provides ZVS conditions for the main MOSFETs. Since all of the switches can achieve soft switching conditions, and the conduction loss of the auxiliary circuit is small, the conversion efficiency for the overall system is improved. When compared with the traditional ZVS implementation methods based on magnetic coupling inductors used in Buck, Boost, and Buck/Boost converters, the proposed topology can prevent current notches on the current waveform of the input source. Since there are no notches on the input source current, when the proposed ZVS implementation method is applied to an interleaved parallel BBC structure, it has a smaller current ripple of the input source. Finally, experimental results are given and analyzed. Based on these results, both the ZVS conditions and efficiency improvement are verified.