A New Current-Doubler Rectifier Based on Three-State Switching Cell for Buck Derived DC-DC Converters

This paper presents a new current-doubler rectifier for application on buck derived DC-DC converters, such as, push-pull, half-bridge, full-bridge, dual-bridge, NPC three-level, and others. This new proposal, named as Three-State Rectifier (TSR), is generated using the three-state switching cell. The proposed rectifier is similar to the Center Tapped Rectifier (CTR), and to the current-doubler rectifier named Interleaving Rectifier (IR). The new rectifier circuit is an alternative to substitute the previous rectifiers topologies, operating with rectifier diodes only, or with synchronized switches depending on the output voltage rating. Advantages of such a new proposal are: the current through the components of the converter are less pulsated which reflects in the conduction losses reduction and the current in the secondary winding of the transformer reaches maximum half of the output average current. The disadvantage of the proposed converter is that the sizes of the autotransformer and the inductor, both equals, are 20% higher than the sizes of the inductors of the IR rectifier. In order to verify the theoretical analysis and compare its performance with similar ones proposed in literature, experimental results consisting of relevant waveforms and curves from a full-bridge phase-shift control DC-DC converter with TSR rectifier and IR rectifier are presented, for a 1.5kW output power prototype, an input voltage of 400V and output voltage of 60V.