Interleaved Flyback Converters with Zero-Voltage Switching

• Main Authors: Peng-Yu Su, 蘇鵬宇
• Other Authors: Hung-Liang Cheng
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/20305064192950453900

碩士 === 義守大學 === 電機工程學系 === 102 === This thesis proposes a novel dc-to-dc converter that consists of two interleaved flyback converters with zero-voltage switching-on characteristic. Both flyback converters use power MOSFETs as the active switches. With no need to use any components for active-clamping circuit or snubber circuit, both active switches can operate at zero-voltage switching-on(ZVS) by freewheeling the converter current through the body diode of the MOSFET. The switching losses can be effectively reduced, thus improving the overall circuit efficiency. As compared with traditional flyback converter, the interleaved converter has the advantages of lower current and voltage ripples. It helps to reduce the voltage and current stresses on the circuit components, leading to increase the circuit reliability. The steady-state analyses for different operation modes are provided and the mathematical equations for designing circuit components are conducted in this thesis. Finally, a 200-W prototype circuit was built and tested to verify the feasibility of the proposed circuit. Base in the experimental results, both active switches actually operate at ZVS. The proposed circuit is with satisfactory performance and the measured circuit efficiency is 91.3%.