A Single-Phase Single-Stage Three-Level AC/DC Resonant Converter Operating with a Wide Output Voltage Range

In this paper, a single-phase single-stage three-level AC/DC converter with a wide output voltage control range is presented. It integrates a PFC converter and a three level DC/DC converter. The proposed converter operates with a fixed frequency and provides a wide controllable output voltage (200VDC~430VDC) with high efficiencies over a wide load range. The input boost inductors operate in a discontinuous mode to improve the converter's power factor. In addition, all the switching devices operate with ZVS, and the converter's THD is small at full load. The feasibility of the proposed converter is verified with experimental results of a 1.5kW prototype.