Utilization of an Active-Clamp Circuit to Achieve Soft Switching in Buck Converters

• Main Authors: Kuang-Yuan Liu, 劉光轅
• Other Authors: Ming-Chieh Tsai
• Format: Others
• Language: en_US
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/61222071571941757618

碩士 === 大同大學 === 電機工程研究所 === 88 === Abstract: Zero-voltage-switched converters can absorb all major parasitic components into the resonant circuit, including transistor output capacitor, diode junction capacitor, but it has high peak voltage stress across the power switch that has caused more switching losses in the high frequency switching. A method of improving the performance of zero-voltage-switched buck converter is proposed, based on clamping the drain-to-source voltage of the power switch using an active clamp network. The addition of the active clamp circuit can reduce the power dissipation to attain high efficiency that has clamped peak voltage across the switching transistor. Principle of operation, simulation and experimental results are presented in this thesis. It can achieve zero cross switching and clamp peak voltage to reduce the power losses in the power converters.