| Title |
Active-Clamp AC-DC Converter with Direct Power Conversion |
| Authors |
Yong-Won Cho ; Bong-Hwan Kwon |
| DOI |
10.6113/TKPE/2012.17.3.230 |
| Keywords |
active-clamp circuit; zero-voltage switching; zero-current switching |
| Abstract |
This paper proposes an active-clamp ac-dc converter with direct power conversion that has a simple structure and achieves high efficiency. The proposed converter is derived by integrating the step-down ac chopper and the output-voltage doubler. The proposed converter provides direct ac-dc conversion and dc output voltage without using any full-bridge diode rectifier. The step-down ac chopper using an active-clamp mechanism serves to clamp the voltage spike across the main switches and provides zero-voltage turn-on switching. The resonant-current path formed by the leakage inductance of the transformer and the resonant capacitor of the output-voltage doubler achieves the zero-current turn-off switching of the output diodes. The operation principle of the converter is analyzed and verified. A 500W prototype is implemented to show the performance of the proposed converter. The prototype provides maximum efficiency of 95.1% at the full load. |