A Family of Class EF Resonant Inverters With Constant AC Voltage Output and Load-Independent Characteristics

A family of Class EF resonant inverters with constant ac voltage output and load-independent characteristics is proposed in this article. Moreover, the design principle of Class EF resonant topologies and their load-independent characteristics are concluded. The low voltage or current stress across the switch can be achieved by the second-order resonant network. Furthermore, the common-ground Class E/F resonant inverter and its load-independent design procedure are introduced. Constant ac voltage output and zero-voltage switching can be achieved by the proposed inverter for a wide load range. To validate the theoretical analysis, the 1-MHz experimental prototype is built and the peak efficiency is 93.4%.