POWER CONVERTER, DC SUBSTATION, DC POWER TRANSMISSION SYSTEM AND CONTROL METHOD OF POWER CONVERTER

摘要

PROBLEM TO BE SOLVED: To suppress and prevent blowout of a conductor wire and arc generation, by reducing a current flowing from a DC capacitor into an IGBT leg upon short circuit of a semiconductor leg.SOLUTION: In the power converter having an arm configured of one or a plurality of unit converters in cascade connection, the unit converter has a main circuit of chopper configuration where semiconductor legs are connected with a DC capacitor. At least some semiconductor legs have a semiconductor module, and a pressure thyristor is connected in parallel with the DC capacitor. Inductance (LS) of a discharge path from the DC capacitor via the pressure thyristor is small and satisfies the following conditions, so that a current having a current rise rate higher than the current rise rate tolerance of the pressure thyristor can be fed when the pressure thyristor is turned on. LS