METHOD FOR CONTROLLING A MODULAR MULTI-LEVEL CONVERTER, CONTROL DEVICE FOR A MODULAR MULTI-LEVEL CONVERTER, AND MODULAR MULTI-LEVEL CONVERTER HAVING SAID CONTROL DEVICE

摘要

The invention relates to a method for controlling a modular multi-level converter (4) having sub-modules (9), wherein each sub-module (9) has semiconductor switches (T1,T2), wherein the semiconductor switches (T1,T2) are controlled using a switching frequency (f) in order to provide an alternating voltage (16) as the output voltage of the converter (4), characterised in that an operating state of the converter (4) is determined and the switching frequency (f) of the semiconductor switches (T1,T2) is set according to the operating state, such that an operating aspect of the converter (4) is optimised. The invention also relates to a control device for a modular multi-level converter and to a modular multi-level converter having said control device.