Series Resonant Converter with Volume Optimization and Efficiency Balance

• Main Authors: CHUN-LIN CHEN, 陳俊霖
• Other Authors: Huang-Jen Chiu
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/63925247887804145077

碩士 === 國立臺灣科技大學 === 電子工程系 === 102 === This thesis presents a series resonant converter (SRC) with volume optimization and efficiency balance. The front stage is a CCM buck converter. The output voltage of the post-stage SRC is sensed and can be regulated under full-range load conditions by adjusting the duty cycle of the buck converter. The SRC is operated around the first resonant frequency to reduce the volume of the magnetic components. Zero-voltage switching and synchronous rectification are adopted to improve the efficiency and increase the power density. In addition, a novel feedback controller is proposed in this thesis to lower the switching frequency at light loads, while raise the switching frequency at heavy loads. A DC-DC power converter with an input voltage of 380 V, an output voltage of 12 V, and rated output current of 25 A is implemented. The switching loss at light load can be reduced with the presented control scheme. The load regulation is within 1%. Also the experimental results are provided to confirm the theoretical analysis.