A New High-Efficiency Single- Stage AC/DC Converter with Power Factor Correction

• Main Authors: Jen-HaoWang, 王任浩
• Other Authors: Hong-Tzer Yang
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/91398282924183916256

碩士 === 國立成功大學 === 電機工程學系 === 102 === The thesis proposes a new high-efficiency, single-stage power factor correction (PFC) AC/DC converter by integrating a buck-boost power factor corrector with a flyback DC/DC converter. By replacing the inductor of PFC semi-stage with a transformer, the proposed converter not only achieves PFC, but low DC-bus voltage by providing a direct power transfer (DPT) path from the input side to output load directly. On the other hand, an energy-recycling path is designed to recycle the energy and suppress the voltage spike caused by the leakage inductance on the power switch to achieve electric isolation and to avoid the damage on power switch, as turned off in the flyback DC/DC converter. The operation principles, steady-state analysis, design guidelines of the proposed converter are presented in the thesis. To verify the effectiveness of the proposed converter, a 100 W prototype circuit with 85 Vrms to 265 Vrms line inputs and output voltage of DC 48 V has been implemented. The experimental results show that the voltage spike on the power switch can be suppressed effectively and the reverse recovery current from diodes can also be alleviated. Moreover, close-to-unity PF and maximum DC-bus voltage of well below 150 V can be obtained with the maximum circuit efficiency of 94 %.