A Dimmable Light-Emitting Diode (LED) Driver With Mag-Amp Postregulators for Multistring Applications

Author

Chen, W. ; Hui, S.Y.R.

Author_Institution

Aero-Power Sci-Tech Center, Nanjing Univ. of Aeronaut. & Astronaut., Nanjing, China

Volume

26

Issue

6

fYear

2011

fDate

6/1/2011 12:00:00 AM

Firstpage

1714

Lastpage

1722

Abstract

Current imbalance should be avoided when multiple LED strings are connected in parallel. In this paper, a dimmable LED driver with magnetic-amplifier postregulators for multistring applications is presented. Powered by a common master source, parallel LED strings are individually regulated by their corresponding adaptive slave sources for current balancing in this proposal. Without linear current regulators, the proposed driver offers relatively high efficiency. Its structure is simpler than multiconverter structures for red, blue, and green LED applications, and is particularly suitable for LEDs with wide parameter variations. The performance of the proposed driver is experimentally verified by a 16.5-W prototype with a load of three 5.5-W LED strings.

Keywords

light emitting diodes; magnetic amplifiers; adaptive slave source; common master source; current balancing; dimmable light emitting diode driver; linear current regulator; mag-amp postregulator; magnetic amplifier postregulator; multiconverter structure; multiple LED string; multistring application; parameter variation; power 16.5 W; power 5.5 W; Converters; Driver circuits; Light emitting diodes; Regulators; Resistors; Voltage control; Windings; Current sharing; light-emitting diode (LED); magnetic amplifier;

fLanguage

English

Journal_Title

Power Electronics, IEEE Transactions on

Publisher

ieee

ISSN

0885-8993

Type

jour

DOI

10.1109/TPEL.2010.2082565

Filename

5593889