Comparative evaluation of bidirectional buck-type PFC converter systems for interfacing residential DC distribution systems to the smart grid

This paper discusses three-phase bidirectional high-power factor mains interfaces for application in smart-houses featuring a local DC distribution grid. The DC grid demanded power can be supplied by local DC generators, such as renewable power sources, and/or by the public three-phase AC mains, which gives the option of feeding back power into the mains in case of a low local power consumption. In order to generate a local 400V DC bus, bidirectionally connected to the European three-phase low voltage AC mains rated at 400V line-to-line, buck-type converter topologies are required. Several possible converter concepts are initially presented and further comparatively evaluated based on the following performance indices: total required semiconductor chip area, overall efficiency, overall passive components volume, and required EMI filter damping. As result of the comprehensive evaluation, the Bidirectional 3^rd Harmonic Injection Active Filter Type Rectifier with DC/DC Output Stage is identified as most advantageous topology for the realization of a bidirectional buck-type PFC rectifier in the considered power range of 5 to 10 kW.