I. MOTIVATION
AC-DC power factor correctors operating with the 380V line are suitable as input stages for high power fun-bridge DC-DC converters. For complying with requirements as IEC 61000-3-2, the DC-link voltage of the corrector has to be substantially increased, thus increasing the voltage stress (equal to the link one) on the switches of the full-bridge converter. In a three-level converter, the voltage stress across the power switches is reduced to half of the input voltage, thus reducing the rating of the switches and the conduction losses. The switching losses can be reduced by turning on/off all the switches under a ZVS condition (not suitable for the inner switches at light load, and not for high power applications using IGBTs), or by switching the leading (outer) switches with ZVS and the lagging switches with ZCS (ZVZCS three-level converters [1]–[3]).