Analysis and design of a two-transformer active-clamping ZVS isolated inverse-SEPIC converter

摘要

This paper presents a two-transformer active-clamping zero-voltage-switching (ZVS) isolated inverse-SEPIC converter, which is mainly composed of two active-clamping ZVS isolated inverse-SEPIC converters. The proposed converter allows a low-profile design for liquid crystal display TVs and servers. The presented two-transformer active-clamping ZVS isolated inverse-SEPIC converter can equally share the total load current between two secondaries. Therefore, the output inductor copper loss and the output diode conduction loss can be decreased. Detailed analysis and design of this new two-transformer active-clamping ZVS isolated inverse-SEPIC converter are described. Experimental results are recorded for a prototype converter with an AC input voltage ranging from 85 to 135 V, an output voltage of 12 V and a rated output current of 13.5A, operating at a switching frequency of 65 kHz.