Design Optimization and Performance Evaluation of Class Φ2 VHF DC/DC Converter

The class Φ2 resonant converter is one of the most promising very-high-frequency (VHF) power converter topologies. It comprises a class Φ2 resonant inverter, which provides low switch voltage stress compared to other resonant inverter topologies, and a class E resonant rectifier. In this paper, a design optimization and performance evaluation of the class Φ2 VHF dc/dc converter are presented. Two different topologies are considered. Due to the complexity of the converter operation, the design is performed in several iterations aided by Simplis simulations. The design procedure is illustrated on a 90-W, 160-170-V input and 33-V output voltage class Φ2 dc/dc converter operating at 30 MHz. The experimental circuit is described in details and measurement results are presented. Practical issues with the currently available GaN devices are also discussed.