Reliability prediction and analysis of LED luminaires

LED (Light Emitting Diode) lighting systems (commonly known as LED luminaires) are beginning to experience widespread use in many lighting applications and are slowly becoming accepted as the norm for domestic, commercial and industrial lighting systems. However the reliability of LED luminaries is still unclear due to the long reliability test times. These long test times have become a barrier to research and development which further impacts the market uptake on new LED lighting technology. The proposed research here aims to reduce the reliability test times of LED luminaires from a minimum of 6000 hours to a more practical time frame of 500 to 1000 hours without compromising the reliability standards. The research involved testing of LED Luminaries that are currently on the market. Testing will utilise common techniques that are practiced in the electronics industry to predict suitable life times for LED Luminaries. The test results generated were analysed to determine reliability acceleration factors allowing realistic lifetime predictions into the future. With the results of the tests, further analysis of the LED luminaire failure modes followed. The results indicate that it is possible to move to a reliability prediction based test methodology where the times required (500 to 1000 hours) would be far less than the minimum of 6,000 hours currently being sought and more importantly provide a path for reliability improvement. This will in terms of reliability, enable designers of new LED technologies to rapidly create smart reliable LED light sources that can match market demand.