A reflex-charging based bidirectional DC charger for light electric vehicle and DC-microgrids

This study proposes a novel reflex-charging-based bidirectional DC charger (RC-BDC) with the aim of enhancing light electric vehicle (LEV) battery charging efficiency within a DC-microgrid. The proposed charger topology mainly consists of an unregulated level converter (ULC) and a two-phase interleaved buck-boost charge pump converter (IBCPC), which features low ripple and a high voltage conversion ratio. The RC-BDC can charge the EV battery with a reflex charging current profile, achieving a high battery charging efficiency and a prolonged battery life cycle. In particular, the negative pulse energy of the reflex charging current profile is recovered to reduce the EV battery charge dissipation. A prototype with a power rating of 500-W is also designed and tested to verify the feasibility of the developed RC-BDC concept.