| Title |
Relay Setting Guidelines for Single-Line Ground Fault Detection in Ungrounded Distribution Systems within High-Voltage Customer Premises |
| Authors |
구대현(Dae-Hyun Koo) ; 김종빈(Jong-Bin Kim) ; 박광재(Kwang-Jae Park) ; 이민구(Min-Goo Lee) ; 김재언(Jae-Eon Kim) |
| DOI |
https://doi.org/10.5370/KIEE.2024.73.3.637 |
| Keywords |
Guidelines; Phase-to-ground capacitance; Relay setting; SGR; SLGF; Ungrounded distribution systems |
| Abstract |
Most high-voltage distribution systems within the premises adopt the ungrounded method. However, in the case of multiple branch lines to which the ground fault protection method of ‘GPT+OVGR+ZCT+SGR’ is applied, the voltage value that is detected at GPT tertiary side in the event of a single-line ground fault decreases due to entire phase-to-ground capacitances along all distribution lines, thereby preventing a stable ground fault. There are many difficulties in setting the correction value of SGR for protection. In this paper, we presented a method to accurately and easily set the correction value of SGR in the field by engineers. The accuracy of the proposed method was proven through PSCAD/EMTDC modeling and simulation. |