Design and Implementation of a Novel Retrofit LED Lamp

• Main Authors: Zih-SiangHuang, 黃子湘
• Other Authors: Tsorng-Ju Liang
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/jxvm55

碩士 === 國立成功大學 === 電機工程學系 === 104 === In this thesis, a novel retrofit LED is proposed to replace the T8/40W fluorescent lamp. The proposed retrofit LED lamp contains a frequency sensing circuits, driving circuit and LED module, which is suitable for AC grid, electromagnetic ballast, and electronic ballast applications. The advantages of the proposed retrofit LED lamp are small size and easy to design. The frequency sensing circuits is constructed of a low-pass filter, peak detector circuit, and voltage comparator to clarify the input voltage frequency of the retrofit LED lamp. When the input voltage is low frequency, the switch S1 series connected with LED is turned off. The switch of flyback converter S2 is used to regulate LED current at high frequency switching. When the input voltage is high frequency, the switch of flyback converter S2 is turned off. The switch S1 series connected with LED is used to regulate LED current linearly. The operational principles of the proposed retrofit LED is analyzed and the key parameters of the proposed retrofit LED are designed. Then, the simulation software is used to verify the feasibility of the proposed retrofit LED lamp. Finally, a 22 W retrofit LED prototype is built in the laboratory for both ballasts and universal AC grid voltage applications.