Solid State Transformers: An Overview of Applications and Challenges

The concept of Solid State Transformers (SST) has been around for a few decades. The SST has gained new importance as a component of the smart grid. The SST is capable of integrating many smart functions into the role of a traditional transformer. The major components of the SST are the power electronic converters and the medium frequency transformer. The power electronic converters have to be designed with innovations in topology as well as device characteristics to enable the full functionality of the SST. The design of the medium frequency transformer is also fraught with challenges when compared with that of traditional transformers, namely in core material selection, winding configuration and cooling. This paper presents an overview of the applications as well as the challenges in design of the SST with primary focus on the medium frequency transformer.