지락고장시 중성선 전위상승에 따른 저압기기 스트레스 전압

In this paper we propose multi-grounded neutral design method which was considered of transferred transient overvoltage when line to neutral fault occurs. Specially, In order to confirm the actual transient overvoltage magnitude which occurs on neutral line, we considered some screening(shielding) effects. The screening coefficient was deducted from field test results and calculation in a distribution line which is identical with an actual power line. The purpose of this paper is to attempt to suggest the guidance for grounding skystem design considering limitation of overvoltage for LV side in IEC 61936. The result is based on EMTP simulation and real field faults situation in distribution lines.