Multilevel converter comprising an active AC-DC converter and a resonant DC-DC converter and a control method for operating a multilevel converter

摘要

The present invention relates to a converter (1) comprising: - an active stage (2) for converting an AC input voltage (u in ) at an AC input into an intermediate DC voltage (U Z ); - a DC/DC converter (3) for transforming the intermediate DC voltage (U z ) into an output DC voltage (U out ) at an DC output, wherein the DC/DC converter (2) has a resonant transformer (32, 33), in particular being formed by a resonant circuit (32) and a transformer (33), - a control unit (5) configured - to actively operate the active stage (2) only based on an output DC voltage (U out ) of the DC/DC converter (3), an input voltage (u in ) and an input current of the converter (1), and - to operate the DC/DC converter (3) in an open loop mode.