Slim design of LLC resonant converter for OLED TV by using toroidal transformer

Abstract

LLC resonant converter is used widely in the application of consumer electronics, battery charging, automotive, etc. due to its popularity and ease of control; however, its large footprint size makes it difficult to use in applications that require slim design. In this paper, a slim LLC resonant half-bridge converter is designed by adopting toroidal and EFD type transformers. The components that have a maximum of 15mm height were used in the design. The simulation and experimental designs of a 384W prototype are explained in detail and the simulation and experimental results are shared. Electromagnetic conductivity (EMC) test results are obtained for EFD type core and toroidal type core. The temperature stress test was applied at room condition. The results are as 83° for two pieces EFD type transformer, 81° for toroidal type transformer. The maximum efficiency of the prototype is calculated as 96.5%.