A Single-Stage Three-Level AC/DC Converter for Wireless Power Transfer

In this paper we present a single stage AC/DC resonant converter with application in electric vehicles, that can transfer power through an air gap of 10cm and operates over a wide output voltage range. The proposed single-stage AC/DC converter for wireless power transfer system integrates a PFC converter and a three level resonant converter into one. The proposed converter operates at a fixed frequency and provides a wide controllable output voltage (200Vdc~400Vdc) with high efficiencies over a wide load range due to a phase shift control. Moreover, all the switching devices operate with ZVS, and the converter's THD at full load is small. The feasibility of the proposed single-stage converter is verified with experimental results of a 2kW prototype for wireless power transfer system.