Converter submodule with short-circuit device and power converter having same

A submodule for a power converter, comprising:

• a full bridge circuit comprising at least two power semiconductor branches connected between a first DC voltage node and a second DC voltage node, each power semiconductor branch having a controllable power semiconductor switch with a freewheeling diode connected in anti-parallel thereto;
• a capacitor connected in parallel to the full bridge circuit between the first and second DC voltage nodes;
• and
• a short circuit device comprising at least one selected of the freewheeling diodes anti-parallel to the controllable power semiconductor switches of the full bridge circuit, wherein the controllable power semiconductor switches are not manufactured in press pack design, and wherein the at least one selected freewheeling diode is manufactured in press pack design and rated such that, when a fault occurs in the submodule, the at least one selected freewheeling diode breaks down due to fault conditions and provides a low-impedance short-circuit path between a first AC voltage connection and a second AC voltage connection of the submodule.