Patent ID: 8314602

Claim:
A single phase converter cell module for a voltage source converter system, which converter cell module comprises two switching elements, a capacitor and an autotransformer, wherein the switching elements comprise insulated gate bipolar transistors connected in an H-bridge configuration having a first and a second terminal, characterized in that the autotransformer has a first end terminal, an intermediate terminal, and a second end terminal, wherein the first and the second terminal of the H-bridge configuration are connected to the intermediate terminal and the second end terminal, respectively, wherein the second end terminal of the autotransformer is an output terminal of the converter cell module connectable to another converter cell module, and wherein the first end terminal of the autotransformer is an input terminal of the converter cell module, whereby the autotransformer bypasses said converter cell module in the case of failure occurring in the converter cell module.