Converter with Multifunction Output Protection Circuit and Method

A method for protecting power networks, comprising:

• providing a converter comprising a conversion stage and an output protection circuit;
• wherein the output protection circuit comprises:
• a first input terminal and a second input terminal;
• a first output terminal and a second output terminal;
• wherein the first input terminal and the first output terminal are disposed at a first voltage level, and wherein the second input terminal and the second output terminal are disposed at a second voltage level;
• providing a switch connected between the first input and output terminals or between the second input and output terminals;
• and
• providing a freewheeling circuit disposed between the first output terminal and the second output terminal, the freewheeling circuit comprising an interruptible freewheeling path including a freewheeling switch and a freewheeling diode;
• and a voltage clamping device disposed in parallel circuit connection to at least the freewheeling switch;
• operating in a normal conduction mode, in which the switch is turned on continuously;
• detecting a fault in the power network, and upon detecting the fault in the power network, entering a current limiting mode by activating the interruptible freewheeling path by turning on the freewheeling semiconductor switch and repeatedly turning on and turning off the semiconductor switch.