Fault tolerant control of modular multilevel converters by reference modification

摘要

It is described a method for operating a voltage source converter comprising a modular multilevel converter topology with three electrical output lines (100, 200, 300), each assigned to a different electrical path (110, 210, 310), the method comprising: Identifying at least one sub module (400) of the modular multilevel converter topology as to be defective, wherein the at least one defective sub module (410) is assigned to a first electrical path (110); bypassing the at least one defective sub module (410); and adjusting at least one reference waveform for an electrical quantity of at least one of the three electrical paths (110, 210, 310), for compensating at least partially an influence of the at least one defective sub module (410) on an output signal provided by at least one of the three electrical output lines (100, 200, 300).