Reliability Prediction of Integrated LED Lamps with Electrolytic Capacitor-Less LED Drivers

Abstract

This chapter investigates the reliability of the integrated LED lamps with electrolytic capacitor-less LED drivers. Firstly, the impact of the interaction between the degradations of the LED light source and the driver on the lumen depreciation is studied. The electronic-thermal simulation was carried out to obtain the history of temperatures of LED and driver, the driver's output current, and the luminous flux considering the variations of temperature and current throughout the operation life. It is found that the ultimate lamp's lifetime is significantly less than the individual lifetimes of the preselected LED and driver. It is concluded that it is necessary to apply the electronic-thermal simulations to predict the lifetime of LED lamps when driver's lifetime is comparable to the LED's lifetime. Secondly, this chapter focuses on predicting the catastrophic failure of an electrolytic capacitorfree LED driver during the lumen depreciation process. Electronic-thermal simulations are utilized to obtain the lamp's dynamic history of temperature and

Research Control Devices for LED Light Sources under Their Operating Conditions at Elevated Temperatures

“…Structurally, such circuits are built on integral current stabilizers, have small dimensions, and are relatively low-cost [16,17]. Their wide application is explained by the fact that current stabilization does not require such accuracy as voltage stabilization on an LED.…”