A new architecture for high-frequency variable-load inverters

Abstract

Efficient generation and delivery of high-frequency (HF, 3-30 MHz) power into variable load impedances is difficult, resulting in HF inverter (or power amplifier) systems that are bulky, expensive and inefficient. This paper introduces a new inverter architecture and control approach that directly addresses this challenge, enabling radio-frequency power delivery into widely variable loads while maintaining efficient zero-voltage switching operation. We model the proposed architecture, develop design and control guidelines for it and analyze the range of load admittances over which it can efficiently operate and deliver a specified output power. The opportunities posed by the proposed approach are illustrated through time-domain simulations of an example HF inverter system.