REQUIREMENTS FOR DETERMINING A SELF-IMPLEMENTED DIRECTOR

摘要

A voltage-source converter is connected on its ac-voltage side to a three-phase electric power network via a transformer and on its dc-voltage side to capacitor equipment. The transformer has on its secondary side a first, a second, and a third phase winding, each one with a first and a second winding terminal. Resistor equipment is arranged at the transformer for limiting the current through the converter when connecting the transformer to the power network. The resistor equipment includes a first resistor, connected to the first winding terminal of the second phase winding, and switching equipment is adapted, in an initial position, to block current through the phase windings, in a transition position to form a current path which includes at least the first and the second phase windings and, in series therewith, the first resistor, which current path, when the converter is connected to the transformer, closes through the converter and the capacitor equipment, and, in an operating position, to interconnect all the first winding terminals for forming the common neutral point.