Power density design of SiC and GaN DC-DC converters for 380 V DC distribution system based on series-parallel circuit topology

The power density for SiC and GaN isolated DC-DC converters were estimated, taking the series-parallel circuit topology and novel device characteristics into account. Design consideration for a 300 W 48 V-48 V LLC converter using GaN-FET and a 4800 W 384 V-384 V converter using SiC-MOSFET were conducted by using the power converter exact loss simulator. The power density of a low-power low-voltage GaN converter was higher than that of single SiC high-power high-voltage converter, and the potential of the series-parallel circuit topology was shown. Standardized high power density converters are attractive for future DC distribution system. This design contributes to realizing highly efficient and space-saving DC distribution system.