Enabling DC Microgrids with Direct MV DC Interfacing DAB Converter based on 15 kV SiC IGBT and 15 kV SiC MOSFET

The 15kV SiC IGBT and 15kV SiC MOSFET have been recently developed to enable non-cascaded high-frequency (HF) MV converters. Such direct MV DC interfacing Dual Active Bridge (DAB) converter is getting popular for DC micro-grid application due to higher efficiency, higher power-density and higher MTBF over the cascaded DAB topology. The high dv/dt in these devices on hard-switching with their inherent parasitics, causes increased EMI and switching loss. The suitability of the two family of SiC devices for an application, depends on the switching frequency, load range and magnitude of power, operating temperature and converter power density. This paper compares the two devices for a MV DAB application for dc micro-grid based on simulation and also with supporting MV side converter experiments up to 10kV DC bus and under 5-20kHz switching frequencies.