Accelerated testing method of LED luminaries

With rapid development of lighting emitting diode (LED) market, more people are focusing on reliability testing method of LED luminaries system. However, it is difficult to use traditional reliability testing method for electronic products to assess LED luminaries with high reliability and long life. In this paper, reliability testing methods applied on LED, LED luminaries and other fields are reviewed shortly, and step stress accelerated life test (SSALT) and step stress accelerated degradation test (SSADT) are selected for exploring reliability testing on commercial available LED systems. According to special characteristic of LED system and advantage of each method, both of methods are combined into one testing plan for evaluating system life. Proposed methods are also conducted on one thermal testing example by focused on commercial available LED bulb and lamp-cup systems. Explored results suggest that step stress accelerated test is an effective accelerated test method for LED luminaries. At the same time, there are still many challenging aspects for system reliability test, such as complicated failure mechanisms, Life gap among subsystems and also product manufacturers and lack of appropriate models to extrapolate. To assess the system reliability in future, an assessment procedure to subsystems is proposed by combining mentioned step stress accelerated test and system statistics analysis methodologies recommended in recent literature.