Interleaved auxiliary resonant snubber for high-power, high-density applications

Abstract

Power density has become increasingly important for applications where weight and space are limited. New wide-bandgap (WBG) devices, combined with soft-switching, now allow inverters to shrink in size by pushing to higher switching frequencies while maintaining efficiency. This paper proposes a novel interleaved auxiliary resonant snubber for high-frequency soft-switching to reduce volume while maintaining efficiency. The design of an auxiliary resonant snubber is discussed; this allows the main GaN MOSFETs to achieve zero voltage switching (ZVS). The auxiliary switches and SiC diodes achieve zero current switching (ZCS). While soft-switching minimizes switching loss, conduction loss is simultaneously reduced for high-power applications by interleaving two high frequency legs.