Study and Implementation of High Efficiency LLC Half Bridge Series Resonant Converter with Variable Frequency

碩士 === 國立臺灣海洋大學 === 電機工程學系 === 99 === This thesis focuses on the study and implementation of a LLC series resonant converter with synchronous rectification which is to develop high-efficiency for power converters. Among many switching power supply topologies, there are many advantages in LLC resonan...

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Bibliographic Details
Main Authors: Chieh-Liang Chen, 陳玠良
Other Authors: Jung-Chien Li
Format: Others
Language:zh-TW
Published: 2011
Online Access:http://ndltd.ncl.edu.tw/handle/50458932591818571809
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Summary:碩士 === 國立臺灣海洋大學 === 電機工程學系 === 99 === This thesis focuses on the study and implementation of a LLC series resonant converter with synchronous rectification which is to develop high-efficiency for power converters. Among many switching power supply topologies, there are many advantages in LLC resonant converters. It makes full use of parasitic components and technologies to achieve zero voltage resonant switching to reduce switching losses and reduce the adverse effects caused by parasitic components. It can be obtained by variable frequency mode to increase the output gain when the input voltage drops. However, for LLC resonant converter, the output voltage drift is caused by voltage instability when there is no load or light load.Therefore, the subject of article comprises converters which are operating at light load or no load. The combination of burst mode is to improve the system characteristics. At the same time, it will reduce the standby losses. This thesis is for describing the LLC structure operations and design. MATHCAD software was used to simulate the voltage frequency response and to understand the influence quality factor Q and the K factor of circuit. Finally, a 120W prototype converter with input 220 VAC and output 12VDC is implemented to verify the theoretical analysis and control strategies. Experimented results show that LLC resonant converter with synchronizer rectifier can provide power to a computer or LED lighting and suitable for energy-saving concept in the future.