| Title |
An Analysis Method for the Transient Ground Impedance Using Variable Frequency and Lightning Impulse Current |
| Authors |
Ju-Hong Eom ; Sung-Cheol Cho ; Tae-Hyung Lee |
| Keywords |
Transient Ground Impedance ; Effective Impulse Impedance ; Grounding System |
| Abstract |
The transient ground impedance depending on configuration, size, and material of grounding electrodes as well as the shapes of impulse currents, has a significant affect on the performance of the grounding system. This paper presents experimental results in regard to the analysis method of transient ground impedance using the lightning impulse and variable frequency currents. Also a new estimation method to replace the effective surge impedance for transient ground impedance was proposed. The ground electrodes used in this experiment are virtual ground electrodes including both resistance and inductance components, carbon ground electrode with 1[m] length, copper electrode with 9[m] length and counterpoise with 40[m] length. Ground impedances using the proposed method were measured respectively. Comparing with the ground impedance using variable frequency current, the conventional ground impedance(Z₁) calculated from the peak values of impulse voltage and impulse current is observed more correct method for evaluating the performance of ground electrode than the effective surge impedance. |