Benefits of Silicon Carbide Schottky Diodes in Boost APFC Operating in CCM

Boost derived Active Power Factor Correction (APFC) imposes high stress on the main diode and main switch due to the high reverse voltage which may result in a very high reverse current. This study analyses the engineering requirements of the diode and transistor in APFC applications and compares a design that uses a fast silicon diode plus lossless snubber to a design with a Silicon Carbide (SiC) diode without snubber. The theoretical considerations where verified by comparing the performance of an ultra fast diode (MUR860, ON Semiconductor) with a lossless snubber to that of a SiC diode (SDP06S60, Infineon) without a snubber, in 1kW Boost APFC stage. The experiments confirm the conclusions of the theoretical prediction that the SiC is an excellent technological solution to Boost APFC stage operating under CCM conditions.