A Lossless Passive Snubber Circuit for Three-Port DC–DC Converter

In this article, a soft-switched nonisolated high step-up three-port dc-dc converter is presented for hybrid energy system applications. In the proposed converter, the soft-switching condition is provided for semiconductor elements by a passive lossless snubber without adding any extra active switch or adding any additional semiconductor element in the main power path. The proposed converter is a high integration of single-stage power conversion with multiple input sources and battery port, while the voltage stress of the main switch is kept low. All these benefits have led to high efficiency in comparison to other converter counterparts. Operating principles of the proposed converter are discussed in detail, and design considerations are presented. Finally, experimental verifications are provided to illustrate the feasibility and effectiveness of the proposed converter.