Title :
Control scheme for decoupling auxiliary power supply in dimmable LED drivers
Author :
Liang Jia ; fang, dagang ; Yan-Fei Liu
Author_Institution :
LED Syst., Global Design Center, Philips Electron. North America, Rosemont, IL, USA
Abstract :
Integrating an auxiliary (AUX) power supply into LED drivers is a popular trend to facilitate LED luminaire system design and reduce system cost and complexity. This AUX power supply can be used to power LED fixture cooling, lighting controller or other suitable electronic devices. In this paper, a cost effective architecture based on Flyback topology is proposed for both constant current (CC) output for LED drive and constant voltage (CV) output for AUX supply. A novel nonlinear ramp based control scheme is invented to decouple the main CC power train from the CV AUX supply and avoid LED output flickering. Small signal modeling is presented to highlight the advantages of this control scheme over conventional peak current mode control. This scheme has been implemented successfully for a 40W dimmable LED driver with a 12V 3W AUX supply.
Keywords :
driver circuits; light emitting diodes; network topology; power control; power supply circuits; AUX power supply; CC power train; auxiliary power supply; constant current; constant voltage; dimmable LED drivers; flyback topology; lighting controller; nonlinear ramp based control scheme; power 3 W; power 40 W; power LED fixture cooling; voltage 12 V; Equations; Light emitting diodes; Lighting; Logic gates; Mathematical model; Power supplies; Windings; Active Cooling Power Supply; Dimmable LED Drivers; Flyback Converter Modeling; Nonlinear Ramp Control; Small Signal Model;
Conference_Titel :
Energy Conversion Congress and Exposition (ECCE), 2014 IEEE
Conference_Location :
Pittsburgh, PA
DOI :
10.1109/ECCE.2014.6954122
