Reliability Assessments Using Stochastic Degradation Process for Cumulative Damage Models in Failure Time Analysis

The failure-time data analysis and testing methods are unsuitable for reliability analysis of such highly reliable products. Degradation data can particularly in applications in which few or no failures are expected, provide considerably more reliability information than would be available from traditional censored failure-time data. High – power white light – emitting diodes (HPWLEDs) have attracted much attention in the lighting market. However, as one of the highly reliable electronic products with may be not likely to fail under the traditional life test or even accelerated life test. In this paper, the general degradation – data – driven method (DDDM).Which is based on the general degradation path model, was used to predict the reliability of HPWLED through analyzing the lumen maintenance data collected from the IES LM-80-08 lumen maintenance test standard. It is a big challenge to obtain sufficient amount of time-to-failure data by testing such products under the normal operating environments and sometimes even under harsher conditions.