Next-Generation Electrical Transformer Helps Lay Foundation for Smart Grid

Achievement date: 

Researchers have developed a fast, small, super-efficient power transformer that greatly exceeds the performance of earlier designs. This second-generation (Gen-II), solid-state transformer (SST), is rated for 15kV electric distribution systems and sits on a silicon-carbide, metal oxide semiconductor field effect transistor (SiC MOSFET).


The technology behind the Gen-II SST will help usher in the many benefits of the smart grid, including distributed generation and the expanded use of renewable power. The device was conceived and built by the Future Renewable Electric Energy Delivery and Management Systems (FREEDM) Center, an NSF Engineering Research Center (ERC),  headquartered at North Carolina State University.


The SST has garnered considerable attention in the research community and in popular technology media for its potentially revolutionizing impact on the power grid. The objective would be to have SST devices replace electromagnetic transformers, which have been around for about a century. The result would be better power quality and efficient integration and control of distributed power generation (such as renewables) and energy storage.

Unlike today’s one-way electric utility model, consumers on a grid equipped with SSTs could engage more interactively with the system. It would allow them to monitor their usage in real time and manage it to better fit their needs.

The FREEDM ERC had previously built a Gen-I SST device as a benchmark, and that model was able to achieve 90% efficiency. The Gen-I SST was named as one of the “Top 10 Emerging Technologies” by MIT’s Technology Review. The Gen-II device leapfrogs its predecessor by delivering close to 98% efficiency, and with a reduced size.