GaN Based Class DE Inverter Operating Up to 40.68MHz with Dead Time Optimization

Abstract:
Class DE inverters are becoming more attractive in Very high Frequency (VHF) power conversion with the continuous improvements of semiconductors and the increasing availability of Wide Band Gap (WBG) switches. They tend to be easier to design, with fewer passive components than other VHF topologies and enhanced efficiency. We discuss key parameters involved in the design of a class DE inverter, as well as practical challenges and how to overcome them. To this end, a modular inverter has been de-signed and tested at 13.56 MHz and 40.68 MHz. It provides an experimental Radio Frequency (RF) output power of 33.59 W into a 50 Ohm load at 40.68 MHz with 90% efficiency. The RF power measurement method is also discussed, and losses distribution evaluated.