Mobile QR Code QR CODE : The Korean Institute of Power Electronics
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
Page pp.230-237
ISSN 1229-2214
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.