An improved zero voltage switching flyback converter topology

An improved zero voltage switching flyback converter topology is presented in this paper. This converter employs an auxiliary circuit that provides ZVS for both the main and auxiliary and it permits the operation of the converter at very high frequencies. Operating principle, steady state analysis, and design procedure for the auxiliary circuit of the proposed converter, are given. A 50 W, 260 kHz prototype converter is built to verify the performance. Experiments of the proposed converter show an improvement of about 2% in the overall efficiency as compared to the previous ZVS flyback converter.

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