Zero-voltage switching phase shift full-bridge step-up converter with integrated magnetic structure

A zero-voltage switching (ZVS) phase shift full-bridge (PSFB) step-up converter with integrated magnetic structure is proposed. In order to improve ZVS ranges, an external inductor is imposed. Especially, to save the volume of the magnetic core of external inductor, the external inductor and transformer are integrated into one magnetic core and then the coupling is formed. Furthermore, coupling coefficients are analysed and can be adjusted by the gaps in the three legs of magnetic core. Besides, the fluxes and the maximum flux density in the three legs of magnetic core are also analysed. Finally, a 100 W prototype converter is made and the experimental results are given to verify the analysis.