Study On LED Power Supply Reliability And Life Assessment Of Lamps

Thanks to such advantages as high lighting efficiency,long life,no stroboflash and energy conservation,LED light sources are gradually replacing traditional lamps.Therefore,the study on power supplies for LED lamps has become a hot topic of research in the power electronics industry.As the reliability of LED power supplies determines the quality and service life of LED lamps,it is of great significance to enhance the reliability of LED power supplies.LED lamps are the fourth generation of light sources with a big difference between their actual life and theoretical life.Meanwhile,the problem of imperfect standards and testing systems of LED lamps and the lack of relatively professional testing means and scientific evaluation methods make it necessary to establish a fast and efficient life assessment method.This paper studies the reliability of power supplies for LED lamps,including temperature rise of main components in power supplies,improvement and adjustment of temperature rise in power supplies,analysis of influence weight of electronic components on the output parameters of power supplies by adopting saber software simulation analysis,By adopting a double accelerated life test method,troubleshooting of power supplies.In addition,a fast life assessment method is brought forward,and the data obtained from the test are organized.A relatively proper mathematical statistics method is brought forward.This paper has such main achievements as:(1)For the sample LED lamps,the test is carried out by taking humidity and temperature stress as the accelerated stress in the test and luminous flux attenuation to 70% of the initial luminous flux as the failure criterion,so that the test time is effectively shortened.(2)The reliability of power supplies for LED lamps is analyzed,3D modeling diagrams of power supplies are established,and thermal field simulation analysis is carried out by using simulation software.Thermocouple thermometry is adopted to carry out actualmeasurement of temperature rise of electronic components in power supplies,the simulation results are verified,analyses are made according to the measurement data,and the method of reducing temperature rise in power supplies is brought forward to improve the reliability of LED power supplies.(3)The test data of luminous flux under two different stresses are obtained in the test.Meanwhile,the Weibull distribution is applied to describe the life distribution of tested samples,and the method of least squares and the Arrhenius equation are adopted to carry out statistical analysis of the test data and finally deduce the life of lamps under normal stresses.(4)Analyses of the problems existing in the test and the uncertainties of test results are made to provide reasonable plans and reliable data support for life assessment of LED lamps in the future.