| Title |
Effects of Soil Discharges on the Impulsive Ground Impedance of Ground Rod with Needles |
| Authors |
Yang-Woo Yoo ; Sung-Chul Cho ; Bok-Hee Lee |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2014.28.5.098 |
| Keywords |
Soil Discharge ; Ground Potential Rise ; Ground Rod with Needles ; Lightning Impulse Voltage ; Transient Ground Impedance ; Conventional Ground Impedance |
| Abstract |
Soil discharges near the ground rod play an important role to reduce the ground potential rise and the ground impedance and to help the fault current to spread into the earth. This paper presents the effects of soil discharges on the transient and conventional ground impedances when the lightning impulse voltage was applied to a ground rod with radial needles. The current-voltage (I-V)curves and transient ground impedance curves were calculated based on the measured current and potential traces. Soil discharge behaviors related to I-V curves and transient ground impedance curves were analyzed as a function of the magnitude of lightning impulse voltages. As a result, the soil discharges occurred near the ground electrode contribute to the reduction of conventional ground impedance and limits the ground potential rise effectively under lightning impulse voltages. |