Dimmable AC LED Driver Based on Series Drive

• Main Authors: Po-Hung Chiang, 江柏宏
• Other Authors: 胡國英
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/n2s692

碩士 === 國立臺北科技大學 === 電機工程系所 === 102 === In this thesis, a dimmable AC LED driving circuit with high power factor (PF) and low total harmonic distortion (THD) is presented, which takes series driving. Via the basic unit constructed by the base of the BJT connected with the drain of the MOSFET. And then, several basic units are connected in series to drive several LED strings. By doing so, the problem in floating driving can be removed, i.e., no additional isolated gate drivers are needed. By doing so, the redundant input voltage across the BJT current source can be reduced, thereby reducing undesired power dissipation and improving overall efficiency. Finally, a prototype circuit is established and is controlled by the Field Programmable Gate Array (FPGA). Via simulated and experimental results, the feasibility and effectiveness of the proposedtopology can be demonstrated.