| 摘要 |
This invention is concerned with the control and design of a passive or an active LED lighting system that does not need electrolytic capacitors in the entire system and can generate light output with reduced luminous flux fluctuation. The proposal is particularly suitable, but not restricted to, off-line applications in which the lighting system is powered by the ac mains. By eliminating electrolytic capacitors which have a limited lifetime of typically 15,000 hours, the proposed system can be developed with robust electrical components such as inductor and diode circuits, and it features long lifetime, low maintenance cost, robustness against extreme temperature variations and good power factor. The proposed circuits can become dimmable systems if the AC input voltage can be adjusted by external means. |
