Transformer arrangement and multilevel converter

摘要

The present invention is concerned with a transformer arrangement comprising at least two transformer units, each with primary and secondary windings and a transformer core structure. The latter are merged into one shared transformer core comprising at least one return limb that is part of the closed magnetic flux paths of the at least two transformer units. Sharing return limbs among individual transformer units, in particular when fed with primary voltage signals that have a certain phase shift between each other, helps to reduce the volume and weight as compared to an individual transformer core structure for each of the transformer units. The transformer arrangement is beneficially used in multilevel converters, in particular in railway traction applications.