Dual-Output LLC Resonant Converter with Series Connection in Primary Side and Parallel Connection in Secondary Side

A dual-output LLC resonant converter for LCD-TV applications is presented in this paper. Based on the LLC resonant behavior, the power MOSFETs are turned on at Zero voltage switching (ZVS) and secondary rectifier diodes are turned of, fat zero currents-witching (ZCS). In the proposed converter, the primary windings of two transformers are connected in series so that the primary currents of two ran formers are equal. In the secondary side of tran, formers, two full-wave rectifiers with dual-output configuration are connected in parallel to share the load current and to reduce the current stresses of the secondary windings of tran, formers. The principle of operation, steady state analysis and design consideration of the proposed converter are provided in detail. Experimental results based on a laboratory prototype with 12V/14A and - 12V/14A outputs with 92.7% efficiency for LCD-TV applications, were provided to verify the effectiveness of the proposed converter. Copyright (C) 2009 Praise Worthy, Prize S.r.l. - All rights reserved.