Multi-port bidirectional three-phase AC-DC converter with high frequency isolation

This paper proposes the use of the three-phase single-stage bidirectional ac-dc converter with high frequency isolation as a multiport power converter. The presented topology is suitable for the new concept of distributed generation, or smart-grids, interconnecting various sources and loads, controlling the power flow between them, with only one converter. The phase-shift angle between the primary and secondary side controls the power flow of the converter which is based on the three-phase version of the dual active bridge and associated with the three-state-switching cell. Therefore, a center tap is used in the secondary windings as well as a modified modulation in order to avoid the low frequency content in the third port.