Power Conversion Using Silicon Carbide

Silicon carbide (SiC)semiconductors offer revolutionary improvements in power electronics due to much lower conduction and switching losses, higher switching frequencies, higher voltage capability, higher operating temperatures and other superior properties relative to standard silicon. Losses in a converter will be decreased by a factor of ten, frequency will be increased by a factor of ten and size/weight will be reduced by a factor of five. These translate directly to greater mobility for nearly all power sources, including variable speed (VS) gensets, fuel cells, PV cells and nearly all of the scavenging methods being considered by the Army and Navy. After several decades of development, SiC semiconductors are nearing introduction, particularly at low power. Based in part on prior work, the applicant will develop baseline SiC technology for use in a wide variety of Army applications in the 250 watt to 2,000 watt range, and also higher power levels. The initial effort will focus on a SiC converter for a 2 kW MTG with VS capability. The converter will be integrated tightly into the end of the PM generator. Generator/converter integration is possible for the first time due to the high temperature capability of the SiC switch (over 400 degrees C)compared to a standard silicon switch (125 degree C). In the base work, a preliminary design will be completed and assessed. In the optional work, several prototype SiC MOSFETs appropriate for this converter will be fabricated in a TO-220 package.