Bidirectional three-phase buck-+boost-type PFC rectifier for bipolar DC distribution systems

This paper presents new three-phase high power factor ac grid interface circuits appropriate for future bipolar dc active distribution networks. The ac-to-dc power converter concept is constructed by combining a six-switch buck-type PFC converter and a bipolar dc-dc boost-type inverting-link circuit. The characteristics of this concept, including an appropriate modulation and control structure, are described in this paper. Simulation results validate the circuit operation.