Medium Voltage DC Bus Enabled by Series Connection of SiC Mosfet Based Three Port DC-DC Converters

Abstract

This paper presents development of Medium Voltage(MV) DC bus using series connection of Modular DC-DC Converter blocks. The MVDC bus is developed using Three Port Triple Active Bridge(TAB) DC-DC converter, which integrate Renewable Energy Sources(RES) and Energy Storages(ES). The TAB DC-DC converter units are three port high frequency transformer isolated phase shifted converters which integrate RES and ES with an output dc bus. Multiple of this DC-DC converter output dc buses can be connected in series to obtain a Medium Voltage DC Bus. The three port TAB converters for this series connection of converters, use 1200V & 1700V SiC Mosfets as switching devices with a three port high frequency transformer providing galvanic isolation among the three ports. In this paper, two laboratory prototypes of the three port TAB converters are connected in series to demonstrate MVDC bus(>2kV). Three port TAB converter, Gate Drivers for TAB converters, Three Port High Frequency transformer, along with independent power & voltage control for three port TAB Converter is discussed here in this paper with experimental verification.