Designing a 1kW GaN PFC stage with over 99% efficiency and 155W/in3 power density

Stringent requirements on higher power density and efficiency for power electronics converters in applications such as server/telecom power systems and industrial motor drives necessitate transformative changes in power electronic architecture as well as replacement of Si based FETs with wide bandgap devices. For power-factor-correction (PFC) circuits, the path for greater power density necessitates the transition from Si based dual-boost to GaN based totem pole (TP) structure, which enables designers to reach over 99% efficiency at twice the power density of Si based converters. This paper compares GaN based TP PFC with conventional Si based topologies, and details design steps for above 99% efficiency and 155W/in³ power density in the switching network.