Implementation of Flyback Converter for LED Lighting
| Autor: | Cheng-Han Chiang, 江承翰 |
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| Rok vydání: | 2013 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 101 Light-Emitting Diodes (LEDs) are no longer confined to use in commercial signage and now moved firmly, and with unquestioned advantages, into the field of commercial and domestic lightning. However, about 20~22% of electric energy in the world is used for lighting. At present, flyback converter has been widely used because of its relative simplicity and excellent performance in power converters. In this thesis, flyback converter operated in discontinuous conduction mode (DCM) is adopted as an off- line LED driver for applications. This LED driver is suitable for cost sensitive applications due to the minimal component parts and a very simple control circuit. The features consisting of a high performance fixed frequency current mode PWM controller, it offers a cost effective solution with minimal external components, including an oscillator, a temperature compensated reference, high gain error amplifier, current sensing comparator for driving a power MOSFET. Besides, one voltage and current controller IC which is used in the secondary side for controlling the output DC voltage and output current of LED lightning. It also provides a feedback through an optocoupler to the PWM controller IC in the primary side. The main function of the LED drive circuit is to limit the current regardless if input and output conditions across a range of operating conditions. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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