225kV A FAULT LOCATION ESTIMATION APPARATUS AND METHOD OF NEUTRAL LINE DRAW OUT TYPE MAIN TRANSFORMER AND UNBALANCED AUTOTRANSFORMER IN AC 225kV FEEDING SYSTEM

摘要

The present invention relates to a fault localization apparatus of a neutral wire-drawn main transformer and an unbalanced autotransformer of an alternating current (AC) 2x25 kV feed device and a method thereof. The present invention includes: auxiliary devices installed in a segment and a sub-segment of a line; and a main device installed in a substation. When a fault occurs due to a short circuit fault or a ground fault between the line and an electric car line, the auxiliary devices provide, to the main device, neutral point current information and impedance information of an autotransformer provided on the line. The main device uses the neutral point current information and the impedance information to calculate an accident occurrence section and a fault point in the accident occurrence section. According to the present invention, the fault localization apparatus of a neutral wire-drawn main transformer and an unbalanced autotransformer of an AC 2x25 kV feed device and the method thereof are efficient and precise and reduce construction costs by complementing an existing circuit analysis method using boost current and line impedance.