Design and optimization of a GaN GIT based PFC boost converter

The advent of GaN power devices brings the possibility of pushing up frequencies of power electronics system beyond the capacity of conventional Si counterparts. To harvest the high frequency operation benefits of GaN technology, not only GaN devices should be used optimally by providing proper switching and conduction conditions to best accommodate parasitic elements inherent with the devices, other components should also be capable of facilitating high frequency operation. In this paper, PFC boost converter is used as a platform to harvest the benefits of GaN technology and, at the same time, to uncover the limitations in pushing power electronics systems up. A 600W PFC boost converter with a maximum switching frequency of 3MHz is designed and implemented, which reached an average efficiency of 98.5%. The results indicate that, when properly used, a GaN PFC boost converter could operate at a frequency that is beyond the reach of conventional Si ones. As well, with availability of GaN devices, high frequency operation of power electronics systems is no longer limited by the lack of switching devices but by practical issues e.g. high frequency magnetic materials, high frequency controllers, etc.