A Reduced Switch Multiport AC-DC Converter with Galvanically Isolated Auxiliary DC Port

In this paper, a new reduced switch multiport AC-DC converter with a galvanically isolated auxiliary DC port is proposed for hybrid microgrid applications. The proposed single-stage architecture is formed by merging a bidirectional four-switch three-phase AC-DC voltage source converter (VSC) with two dual active half-bridge (DAHB) DC-DC converters, the primary side switches of which are shared with the VSC. The proposed bidirectional multiport converter is able to manage the power flow among three ports by adjusting the modulation index of sinusoidal pulse width modulation (SPWM) and the phase-shift angle. The converter achieves power factor correction (PFC) at the AC Port and all its switches can achieve soft-switching in continuous conduction mode (CCM). The proposed converter's operation, control and analysis are presented in this paper. Experimental results from a prototype that confirm the converter's viability are shown as well.