Current-fed GaN front-end converter for ISOP-IPOS converter-based high power density dc distribution system

A current-fed ac-dc converter using Gallium Nitride (GaN) power devices has been proposed to realize high power density ISOP (Input Series and Output Parallel)-IPOS (Input Parallel and Output Series) converter-based dc distribution system. The current-fed converter becomes the strong candidate in the ISOP-IPOS converter-based dc distribution system because this system expands the possibility of the ac-dc converter design without taking the converter I/O voltages and its output power into account. An 1 kW prototype with the efficiency of 95.5% has been developed by using GaN-HEMTs to show the feasibility. Design consideration for the GaN converter has been also conducted quantitatively taking the low on-resistance, the high-speed switching behavior and its own device structure into account. The ISOP-IPOS converter-based dc distribution system takes full advantage of the current-fed converter and the converter using GaN devices contributes to realizing higher power density dc distribution system.