New 1000V SiC MOSFETs enable improved efficiency, density, and cost tradeoff space for PFCs

This paper presents an improved design space for AC/DC converters utilizing 1,000V SiC MOSFETs by taking advantage of their low conduction and switching losses in a simple and cost-effective two-level topology. An efficiency- and cost-optimized 20 kW hardware prototype Power Factor Correction (PFC) is designed, implemented, tested, and compared against similarly rated AC/DC converter topologies with primary emphasis on the Vienna rectifier using SJ MOSFETs. The paper shows that the proposed two-level 20 kW SiC-based AC/DC converter achieves an efficiency/power density/cost point not presently reachable using Si Supper Junction MOSFETs or IGBTs. The prototype has demonstrated a full-load efficiency of 98.2%, an estimated power density of 3.9kW/dm
³
and THD
_I
of 2.4% @ V
_GRID
= 480V, V
_LINK
= 800V, and F
_sw
= 48 kHz.