| Title |
Impulse Ground Impedances of a Deeply Driven Ground Rod Combined with Different Shape Grounding Electrodes |
| Authors |
Bok-Hee Lee ; Su-Bong Lee ; Keun-Chul Chang |
| Keywords |
Potential rise ; Effective impulse impedance ; Rise time ; Deeply driven ground rod ; Grounding grids ; Counterpoises |
| Abstract |
This paper describes the characteristics of effective impulse ground impedance of deeply driven ground rods combined with grounding grid or counterpoises with needles. The potential rises of the test ground electrodes were measured as a function of the rise time of applied impulse currents and the effective impulse ground impedances were calculated. The impulse ground impedances of deeply driven ground rods strongly depend on the rise time of impulse currents and significantly reduced by the connection of grounding grids in parallel. |