A high-frequency-transformer-isolated two-switch three-phase ac-to-dc converter with low harmonic distortion

This paper presents a high-frequency-transformer-isolated, single-stage, fixed-frequency, soft-switching, three-phase ac-to-dc converter with low line-current harmonic distortion. The converter uses only two switches and a simple control circuit without any active control scheme. Various operating modes of the converter are presented and analyzed. Based on the analysis, design curves are obtained and a design example is presented. The performance of the proposed converter is evaluated using PSPICE simulation and a laboratory prototype with 500 W output (using IGBTs as switching devices).