Lifetime prediction of fluorescent lamps used in photovoltaic systems

Abstract

This paper approaches lifetime prediction of fluorescent lamps in photovoltaic systems by means of an analytical model. This can assist in improving ballast design and extending the lifetime of fluorescent lamps. As a result of our work, the temporal integral of the glow current to starting and the lamp voltage during normal operation normalised to nominal voltage appear to be the two independent variables that describe the influence of startup and continuous operation on lamp lifetime with an acceptable degree of accuracy. The analytical expression found explains 92.4% of the variability in lifetime. Model agreement with original data and its range of application and limitations are also analysed.