Heat-Transfer Network Analyses of Ballast-Integrated Compact Fluorescent Lamps

Abstract

Ballast-integrated compact fluorescent lamps (BCFLs) have been widely used to replace incandescent lamps for saving energy. Most of the BCFLs in recent years have internal electronic circuits and are smaller and much more efficient, compared with old magnetic ballasted types. Accordingly, the thermal reliability of the electronic circuits is more important in new lamps. In addition, the BCFLs covered with outer globes generally have a problem with slow luminous run-up which is strongly concerned with the temperature of amalgam. These two issues seem independent, but the both are linked technologically from the viewpoint of a heat analysis. Although software for computational fluid dynamics (CFD) is often utilized to treat heat problems, here we focus on the heat-transfer network analysis that solves the steady and nonsteady-state problems for BCFLs with and without outer globes. This analysis is proved to be valid for calculating the temperatures and heat flux of many kinds of BCFLs, in which the temperatures calculated for steady problems are in accordance with the measured one less than 10 K difference.

Keywords:

• compact fluorescent lamp
• electronic circuit
• heat-transfer
• luminous run-up characteristic