High-Power SiC BJTs among Finalists in NASA iTech Challenge

June 19, 2018 by Paul Shepard

Last week, the U.S. Department of Energy (DOE) and NASA held the NASA iTech Cycle II forum, an event devoted to solving tough energy challenges on Earth and in space. DOE's Advanced Research Projects Agency-Energy (ARPA-E) joined NASA in hosting the event, uniting experts from multiple disciplines in the search for new energy technologies with potentially transformative implications for American competitiveness and security, as well as space exploration.

The three finalists included: iFeather, Boulder, Colorado - In-situ Fabrication of Extraterrestrial Aerogels for Transparency, Heat, and Energy Regulation (iFEATHER) for Habitat, Aeronautic and Space Vessel, and Space Suit Applications.

Stanford University, Department of Electrical Engineering, Stanford, California - Two C: Transportation Electrification through Ubiquitous Wireless Charging

WBGlobalSemi, Inc., Lakewood Ranch, Florida - Commercializing High Power Silicon Carbide (SiC) Bipolar Junction Transistors (BJTs) and Power Modules for Power Management and Distributed Power Applications.

WBGlobalSemi, Inc. (WBGS) is seeking to commercialize a new class of high-power SiC BJTs and power modules for use in industrial applications such as aerospace, main grid, micro-grid, traction and military.

WBGS' SiC BJTs claim several price/performance advantages including:

  • High Current: BJTs provide high current and current conductivity modulation with high turn on and turn off speeds and lower cost than IGBT or MOSFET power modules.
  • Lowest Cost: BJTs deliver the lowest cost and lowest conduction loss. In addition, BJTs have low turn on and turn off losses.
  • Smaller Devices: With appropriate drivers BJTs can achieve same frequencies as MOSFETs, or close to, on 1/10th the die on wafer.

Transistor Performance Comparison for the same die size and voltage rating. (click on image to enlarge)

WBGS' current focus is on (a) a 6.5 kV, 50 Amp BJT power module and (b) a 200 V, 3,000 Amp pulsed power module BJT family. These can be manufactured today using the best materials and with tight control over the manufacturing process.

In addition, WBGS has developed optimized driving circuits for various power applications for optimal BJT performance.

10 kHz - 200 kHz, 6.5 kV, 50 Amp BJT, driver, and power module. (click on table to enlarge)

10 Hz, 200 V, 3,000 A pulsed power BJT, driver, and power module. (click on table to enlarge)

"The Department of Energy and NASA represent two of the finest research enterprises in the world, so we were delighted to join NASA in celebrating the importance of innovation in energy technology," said Under Secretary for Science Paul Dabbar, who spoke at the forum Wednesday evening. "Through this collaboration, ARPA-E and NASA have identified critical areas for energy innovation with the possibility of improving life on Earth and in space, and we look forward to future opportunities to collaborate with NASA as we accelerate American innovation."

The forum also served as the final event in the NASA iTech Cycle II Energy challenge. Three innovative energy technology concepts from iFeather, Stanford and WBGS were recognized by a panel of expert judges as finalists in the competition led by NASA and DOE. Technologies under consideration included fuel cells, solar power systems, high capacity batteries, and innovative power management systems.

NASA iTech is an initiative sponsored by NASA's Space Technology Mission Directorate and managed by the National Institute of Aerospace in Hampton, Virginia. ARPA-E lent NASA its expertise in energy technology for this special edition of the iTech challenge, convening a panel of experts from both agencies to evaluate and select the top 10 finalists before the final selections on Thursday.