Review of Dual-Active-Bridge Converters With Topological Modifications

Dual active bridge (DAB) converters inherit favorite features including zero voltage switching (ZVS) capability, wide voltage range, and natural bidirectional power flow. Facing different applications and high market requirements, conventional DAB topologies with various modulations are gradually inadequate, so topological modifications are emerged in literature to deal with these situations. Based on their characteristics of these modified DAB topologies, this paper provides a comprehensive review and classification, and the methodology to modify DAB topologies is proposed. Firstly, basic cells including input/output types, active bridges, transformers, and auxiliary high-frequency networks are introduced. Next, by combining these cells flexibly, modified DAB converters are derived, and they are classified in terms of structural characteristics and discussed in detail. Finally, the characteristics, merits, and demerits of the modified DAB converters are concluded. Evolvement history, future trends, and derivation of new topologies are also analyzed. This paper aims to present a clear picture of the general law and framework of the modified DAB topologies and give the inspiration to derive new DAB topologies to address specific requirements.