Abstract: A method of short-circuiting a faulty submodule for a voltage-source power converter is disclosed. The submodule is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches with anti-parallel freewheeling diodes and optionally non-controllable semiconductor valves. The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode. The method further includes selecting a minimum number of power semiconductor switches suitable to provide a bypass path through the submodule depending on the identified faulty semiconductor device and the determined failure mode and driving the selected power semiconductor switches by a modified driving voltage compared to normal operation to cause them to break down in order to provide a durable, stable, low impedance short-circuit path between the AC voltage terminals of the submodule.

Abstract: A method (36) of short-circuiting a faulty submodule (12, 12?, 12?) for a voltage-source power converter (8) is disclosed. The submodule (12, 12?, 12?) is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches (T1-T4) with anti-parallel freewheeling diodes (D1-D4) and optionally non-controllable semiconductor valves (D1?-D4?). The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode.