20kHz 30kW SiC Converter has 99% Efficiency

June 11, 2015 by Jeff Shepard

Princeton Power Systems has demonstrated for the first time a grid-tied bi-directional power converter intended for commercial use based on a silicon-carbide switching technology platform. The converter operates at 30kW power throughput and 480-Vac, using junction field effect transistor (JFET) devices provided by United Silicon Carbide (USCi) and Princeton Power Systems trigger cards integrated in a unique architecture. The converter demonstrated peak efficiency greater than 99% and sustained 100% power overloads.

The specifications for a commercial GTIB-30-SiC converter using silicon-carbide technology will include a CEC weighted efficiency of 97.5% in a double-conversion bi-directional architecture and will be compatible with advanced batteries over a wide dc voltage range, 208/480 Vac output, and UL-compliant. The companies are planning to introduce a 100kW SiC-based product in 2016.

Wide band-gap Silicon-Carbide devices have a number of advantages over their silicon counterparts. They can handle higher voltages, currents, and power, operate over a broader temperature range, and switch faster with lower losses. These lead to a converter that is smaller, lighter, quieter, more efficient, and with simpler cooling requirements. The power density and conversion efficiency of a commercialized product will be significantly improved over silicon-based converters.

"Technology innovation in power conversion has been at the core of our mission since day one," said Ken McCauley, President & CEO of Princeton Power Systems. "This product demonstration shows that silicon-carbide technology can play a role in highly-efficient and cost-effective commercial products in the very near future, and we intend to expand its use to higher power levels and ultimately across our product line."

The power stage at the heart of the converter was jointly developed by USCi and Princeton Power, using JFET devices from USCi and triggers and controls developed by Princeton Power Systems. The integrated product was designed and tested at Princeton Power's Nationally Recognized Test Lab in Lawrenceville.

"USCi is at the forefront of designing and delivering active switches based on silicon-carbide. Our JFET and Cascode technology deliver the only standard gate drive SiC switch solution, while having the lowest specific on resistance in the industry. These advantages enable the most cost effective SiC solution in the world," said Chris Dries, President & CEO of USCi. "The demonstration at Princeton Power represents a breakthrough in operating an integrated power block using commercially-available silicon-carbide devices."