Two-Transformer Active-Clamping Forward and Flyback Converters

• Main Authors: Jing-Yuan Lin, 林景源
• Other Authors: Yu-Kang Lo
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/51865094129966986322

博士 === 國立臺灣科技大學 === 電子工程系 === 95 === This paper presents a two-transformer active-clamping zero-voltage-switching (ZVS) forward converter and a two-transformer active-clamping zero-voltage-switching flyback converter. Each proposed topology is mainly composed of two active-clamping counterparts. By utilizing two separate transformers, the proposed converter allows a low-profile design to be readily implemented while retaining the merits of a conventional single-transformer topology. Only two switches are required. The circuit complexity and cost are thus reduced. The leakage inductance of the transformer or an additional resonant inductance is employed to achieve ZVS during the dead times, and therefore the converter efficiency are improved. Like the conventional active-clamping converter, the duty cycles of the two switches for the proposed two-transformer topology are complementary. Thus the ranges of the output voltage and the load variation are not affected.