Analysis of novel phase-shifted full-bridge converters with wide ZVS range reduced filter requirement

In this paper, some novel converters are proposed to solve the drawbacks of traditional phase-shifted full-bridge (PSFB) converter. In the primary side of proposed converters, the FB inverter is divided into two half-bridge inverters and the large-sized transformer is replaced by two small-sized transformers. By employing this structure, the zero voltage switching range can be extended and the primary circulating current existing in the additional PSFB converter is removed. In the secondary side, various rectifiers can be adopted to suit for different applications. Moreover, the primary power can be continuously transferred to secondary side in the proposed converters, which contributes to the reduction of output filter requirement. The circuit configuration, operational principle and relevant analysis of proposed converters are introduced in this paper. Experimental results on two typical prototype converters are built to validate the theoretical analysis.