Family of Hybrid dc-dc Converters for Connecting DC Current Bus and DC Voltage Bus

Along with the development of current source converter (CSC) and dc microgrid (DCM), it is foreseeable that topologies which can connect the dc current bus (DCB) and the dc voltage bus (DVB) will become urgently needed in the future grid system, such as the dc grid and electric vehicle with current source terminals. In order to meet this demand, family of hybrid dc-dc converters is proposed for realizing the bidirectional power flowing ability between the DCB and the DVB in this paper, and the potential hybrid dc-dc converters without or with electric isolation are analyzed in this paper. Moreover, for these hybrid dc-dc converters, the basic principle for the modulation operation is presented, and by using a hybrid dual-active-bridge (HDAB) dc-dc converter as an example, the modulation methods for bidirectional transferred power are illustrated, especially for implementing power transferred from the DCB to the DVB. Finally, simulation and experiment results will be used to verify the effectiveness of the HDAB dc-dc converters and the corresponding modulation methods.