Design Challenges of High Frequency High Step Ratio PCB-Based Planar Transformer for GaN Based Dual Active Bridge Converter

Printed copper board (PCB) based planar transformers are a feasible option for dc-dc bidirectional power conversion applications due to their benefits over traditional wire wound transformers. However, they pose challenges when operating at higher frequencies and power levels. These challenges become more pressing when coupled with a high step transfer ratio. The drawbacks make it difficult to employ PCB-based planar transformers for high step conversion applications. In this article, a 5 kW, 1:29, 200 kHz prototype was designed to investigate these challenges linked with PCB-based high step ratio, high frequency, and high power planar transformers. The development of the loss profile and performance assessment have both been done using finite element analysis (FEA) based simulations.