Natural Oscillation Principle-based Burst-Mode PDM-Controlled Class-D Resonant Converter for Inductive Power Transfer Applications

Abstract

A novel prototype of zero-voltage soft-switching (ZVS) high-frequency resonant converter for inductive power transfer (IPT) applications is presented in this paper. By adopting a natural oscillation-based pulse-density-modulation (PDM) scheme, the resonant current of the sending and receiving coils can be continuously regulated under the condition of soft switching; thereby the parasitic oscillation and ringings inherent to the conventional burst-mode PDM can be eliminated effectively. The essential performances on the output power regulation and soft-switching operations are demonstrated in experiment using a class of the 400 W-500 kHz prototype, whereby the validity is evaluated from the practical point of view.