Improved active input current shapers for converters with symmetrically driven transformer

This paper deals with the analysis of new implementations of the recently p roposed active input current shaper (AICS), Using these implementations, th e size of the AICS inductors used in ac-to-dc converters based on "symmetri cally driven" de-to-de topologies (e,g,, half bridge, push-pull, or full br idge) can be reduced and even integrated in only one magnetic core. As in t he 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 de-to-de c onverters (e.g,, fast transient response). Finally, the four proposed imple mentations of the AICS have been experimentally tested.