Publications
Detailed Information
A Multi-Segmented LED Driver with LUT-Based Control using Background Calibration
DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | 김재하 | - |
dc.contributor.author | 이현승 | - |
dc.date.accessioned | 2017-10-31T07:38:00Z | - |
dc.date.available | 2017-10-31T07:38:00Z | - |
dc.date.issued | 2017-08 | - |
dc.identifier.other | 000000146632 | - |
dc.identifier.uri | https://hdl.handle.net/10371/137403 | - |
dc.description | 학위논문 (석사)-- 서울대학교 대학원 공과대학 전기·정보공학부, 2017. 8. 김재하. | - |
dc.description.abstract | Light-emitting diode (LED) lighting is becoming a major illumination method with supports from global energy institutions such as department of energy (DOE) in the United States. It is because LED replacement can save a lot of global energy consumption due to its superior efficacy over conventional light sources. However, for a rapid adoption of LED lighting, lower cost and reliable driver is required.
This thesis presents an AC-powered, boost-converter-based multi-segmented LED driver that maintains a high-power factor (PF) and accurate input current level, using a novel look-up table (LUT)-based digital control with a simple predictive duty-cycle control scheme and background calibration. The presented multi-segmented LED driver aims to reduce the costs of high-voltage capacitors and high-inductance inductor by segmenting the load LEDs into multiple strings and switching the number of LED strings which are connected in series for line regulation and power-factor correction. However, the increased number of power switches calls for a sophisticated control scheme that responds quickly to the switching mode changes and adapts properly to the operating condition changes. The presented LED driver addresses this by employing a LUT that can provide a pre-programmed, arbitrarily fast response to the periodic 220-V AC input, supplemented by a periodic background calibration and optimal switching mode selection to track any unexpected changes in the input, load, and environment conditions. A prototype 220-V AC LED driver with 6-segment LED strings demonstrates a 98.4% power factor (PF), 91% conversion efficiency, 26 mArms input current error, and 67% reduction of discrete component costs while delivering 38.3-W to the load. | - |
dc.description.tableofcontents | Contents
1. Introduction………………………………………………….1 1.1. AC-powered LED Driver ………………………………………......1 1.2. Thesis Organization ………………………………………………3 2. Multi-Segmented LED Driver Architecture ………………4 2.1. Multi-Segmented Boost Converter Topology ………………………4 2.2. LUT-Based Digital Control ………………………………………...6 2.3. Optimizing Component Cost …………………………………….8 3. Switching Scheduling …………………………………….10 3.1. Switching Mode in N-Segmented LED Driver …………………...10 3.2. Time Multiplexing Scheme in N-Segmented LED Driver ………12 3.3. Switch Schedule Allocation ……………………………………....13 4. Duty-Cycle Control ……………………………………….16 4.1. Analysis on Optimal Duty-Cycle Ratio …………………………...16 4.2. Effect on Non-Idealities …………………………………………...20 4.3. Current Feedback Compensation …………………………………22 5. Experimental Results ……………………………………29 6. Conclusion ………………………………………………….36 Bibliography ………………………………………………....37 Abstract(Korean) …………………………………………….40 | - |
dc.format | application/pdf | - |
dc.format.extent | 2836198 bytes | - |
dc.format.medium | application/pdf | - |
dc.language.iso | en | - |
dc.publisher | 서울대학교 대학원 | - |
dc.subject | AC-powered LED Driver | - |
dc.subject | Predictive Control | - |
dc.subject | Lookup-table (LUT) | - |
dc.subject | Boost Converter | - |
dc.subject | Segmentation | - |
dc.subject.ddc | 621.3 | - |
dc.title | A Multi-Segmented LED Driver with LUT-Based Control using Background Calibration | - |
dc.type | Thesis | - |
dc.contributor.AlternativeAuthor | Hyunseung Lee | - |
dc.description.degree | Master | - |
dc.contributor.affiliation | 공과대학 전기·정보공학부 | - |
dc.date.awarded | 2017-08 | - |
- Appears in Collections:
- Files in This Item:
Item View & Download Count
Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.