| Title |
Effects of Ground Faults on the Safety of Persons and Low-voltage Installations in 22.9 ㎸-Y Distribution Systems |
| Authors |
Han-Su KIm ; Jae-Hee Chung ; Kae-Myung Kang |
| Keywords |
IEC standard ; Grounding systems ; Ground faults ; Safety of persons ; Protection of equipment ; Touch voltage ; Step voltage |
| Abstract |
This paper presents experimental results on the safety of persons and protection of low-voltage equipments of the sub-station due to a single-phase ground fault in 22.9 ㎸-Y distribution system. In order to evaluate the hazard voltages and the stress voltage of the low-voltage(LV) equipment due to faults between high-voltage systems and earth based on the newly prescribed KS C IEC 60364 standard series, the verification tests in a 22.9[㎸] neutral multiple grounding system were carried out. From the experimental results, we introduce serious problems causing some discomfort when applying KS C IEC 60364 standard series to the existing domestic distribution system, and the effective protective treasures against temporary overvoltages due to a ground fault in the common grounding which is combined the 22.9 ㎸-Y grounding and the customer"s installation grounding are proposed. As a consequence, it was found that the equipotential bonding is an important prerequisite for the effectiveness of the protective treasures for the safety of persons and LV equipment in the combined 22.9 ㎸-Y and low-voltage grounding system. |