Stackable 270V SiC Regulated Transformer Rectifier Unit (RTRU)

The intent of this SBIR submission is to propose an alternate converter topology for a Regulated Transformer Rectifier Unit (RTRU), using SiC semiconductors, which offers improved performance and reliability while also reducing system volume and mass below what is commonly used today. The effort will pursue a scalable design, specifically via a hot-swappable “N+1” architecture using 5kW modules employing SiC power FETs. The “N+1” architecture provides enhanced reliability, allowing replacement of a single repairable unit while keeping the remaining units online for uninterrupted power. Firmware control strategies will be used to facilitate load sharing between the modules without requiring the modules to be networked together across a communication bus. An initial trade study will compare a system consisting of an active rectifier followed by an isolated two-switch forward converter, referred to as a two-stage system, and a second configuration consisting of a three-phase transformer followed by an active rectifier, referred to as a one-stage system.