Class-E Inverter with Frequency Modulation Control

This paper proposes the frequency-modulation control strategy on the load-independent class-E inverter based on careful observation of the inverter characteristics. The proposed inverter is aimed to have the robustness to the load variations and component tolerances in the output-resonant filter. The main idea is to apply the FM control of the output voltage regulation to the load-independent inverter. The proposed inverter maintains the rated output voltage and high-efficiency operation at high frequencies despite the load variations and the component tolerances in the output-resonant filter. An experimental prototype of the inverter was implemented. The effectiveness of the proposed idea was experimentally validated. The implemented inverter achieved 95% efficiency with the 5.7W output and 1 MHz frequency at the nominal operation.