Application of 24V/20A LLC resonant converter for OLED TVs

Abstract

This study aims to come out with a double transformer resonant converter design that is serially connected in the primary part and parallel connected in the secondary part while using LLC topology. With the help of serial resonance characteristics, the power MOSFETs are conducted at zero voltage switching, therefore the switching power losses on the semiconductor devices are minimized. In the recommended converter, the primary part of two transformers are connected in series in order to transmit the load currents to output in a balanced manner. In the secondary part, the transformers are parallel connected in order to provide equal distribution of load currents. This, in return, decreased the current stresses on the secondary part of the transformers and on the output rectifying diodes. This study provides the working principle of the series resonant LLC converter topologies by designing the PSIM simulation model and laboratory prototype with 24V/20A output for OLED TV power source.