Análise e projeto de conversores para acionamento de painéis de LED orgânico de baixa potência alimentados por rede elétrica CA

Abstract

This work presents some converter topologies aimed to drive an organic light emitting diode (OLED) panel from the AC power grid. The main objective of this work was to develop a converter that can supply power to this kind of load, properly meeting the requirements described in the current standards. Also, the driver should be compact, lightweight and present a slim profile. The system was designed with switching frequencies higher than 100 kHz aiming the size reduction of the magnetic components. Moreover, topologies were analyzed with high step-down characteristic to proper deal with the voltage level of the power grid of 127 VRMS (180 V peak to peak) and the panel rated voltage (21 V), with the capability of current regulation as well, thus allowing for luminosity control. By using a digital simulation, it was possible to evaluate the application of different converters such as the buck-boost/buck two-stage topology, an integrated double buck with tapped inductor and a conventional integrated double buck topology for power factor correction and current regulation. A prototype of na integrated double buck converter designed to supply an output power of 10 W was implemented in the laboratory, whose results are compared to the theoretical data, yielding a driver with high power factor, low harmonic distortion with up to 79 % efficiency.