《A New Single-Phase Single-Stage Three-Level》.pdf

IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 60, NO. 9, SEPTEMBER 2013 3731 A New Single-Phase Single-Stage Three-Level Power-Factor-Correction AC–DC Converter With Phase-Shift Modulation Mehdi Narimani, Student Member, IEEE, and Gerry Moschopoulos, Senior Member, IEEE Abstract—A new three-level ac–dc single-stage converter that Several single-stage ac–dc full-bridge current-fed converters can operate with standard phase-shift pulsewidth modulation is have been proposed [2]; these converters have a boost inductor proposed in this letter. In this letter, the operation of the converter connected to the input of the full-bridge circuit. Although is explained, and its feasibility is confirmed with experimental re- sults obtained from a prototype converter. Finally, the efficiency of they can achieve a near-unity input power factor, they lack an the new converter is compared with that of a previously proposed energy-storage capacitor across the primary-side dc bus, which converter of the same type, and it is shown that the new converter can result in the appearance of high voltage overshoots and has better efficiency, particularly for light-load operation. ringing across the dc bus. It also causes the output voltage Index Terms—AC–DC power factor correction, phase-shift to have a large low-frequency 120-Hz ripple that limits their modulation (PSM), single-stage converters, three-level (TL) applications. converters. The most common type of single-stage ac–dc full-bridge