Nonisolated Bidirectional DC–DC Converters With Negative-Coupled Inductor

A novel solution for nonisolated bidirectional dc-dc converters (NI-BDCs) with advantages of simple topology, high efficiency, and high reliability is proposed. A small negative-coupled inductor (NCI) is employed to split the switch branch in the NI-BDC into two power flows clearly and prevent the freewheeling current from flowing through the body diode of MOSFET. As a result, the reverse-recovery problem of the MOSFET's body diode is alleviated. The topology method is presented and a family of NI-BDCs with NCI is proposed. The idea is further extended to a positive-coupled-inductor (PCI) solution by merging the NCI and the filter inductor into a PCI. And a family of NI-BDCs with PCI is proposed. The key operational principle and design consideration are presented with experimental results given.