Contactless DC connector concept for high-power-density 380-V DC distribution system

Abstract

A contactless DC connector concept has been proposed for next-generation 380-V DC distribution systems in data centers. An LLC resonant DC-DC converter topology with gallium nitride (GaN) power transistors has been applied to realize a highly efficient inductively coupled contactless connector. A prototype of a 1.2-kW 384 V-192 V contactless connector has been fabricated. An efficiency of over 95% and an ideal power density of over 5.0 W/cm3 have been confirmed experimentally under 500-kHz operation. Design considerations for the proposed connector have been also conducted, and the approach for achieving a higher power density of 10 W/cm3 has been presented. The proposed concept contributes to realizing a high-power-density DC distribution system because the functions for both the isolated DC-DC converter and conventional connector are integrated in a single instrument.