Improved active input current shapers for converters with symmetrically driven transformer

Abstract

This paper deals with the analysis of new implementations of the recently proposed active input current shaper (AICS). Using these implementations, the size of the AICS inductors used in AC-to-DC converters based on “symmetrically driven” DC-to-DC topologies (e.g., half bridge, push-pull, or full bridge) can be reduced and even integrated in only one magnetic core. As in the case of other converters with the AICS, the new implementations allow us to reduce the line current harmonics in order to comply with the IEC 1000-3-2 specifications, maintaining all the features of the standard DC-to-DC converters (e.g., fast transient response). Finally, the four proposed implementations of the AICS have been experimentally tested