METHOD AND APPARATUS FOR RESTRICTING NEUTRAL LINE OF ZERO SEQUENCE CURRENT

摘要

PURPOSE: A method and an apparatus are provided to prevent a reverse power flow due to a ground fault malfunction in a distribution system or an unbalanced load by controlling the impedance of a neutral line. CONSTITUTION: A tap controlling unit(660) is connected to a neutral line. The tap controlling unit controls a turns ratio of a secondary winding(640) and a first winding(620). A resistor/reactor unit(650) is connected to the secondary winding. The first winding comprises a A coil part and a B coil part. The both ends of the A coil part are respectively connected to the first grounded side bushing terminal and the tap controlling unit. The both ends of the B coil part are respectively connected to the first power bushing terminal and the tap controlling unit.