| Title |
An Analysis of the Ground Potential Rises and Dangerous Voltages Associated with the Frequency of Ground Currents |
| Authors |
Jong-Hyuk Choi ; Yong-Seung Cho ; Bok-Hee Lee |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2011.25.4.097 |
| Keywords |
Ground Surface Potential Rise ; Dangerous Voltage ; Touch Voltage ; Step Voltage ; Grounding Impedance |
| Abstract |
The most important object of grounding systems is to protect human being from electric shock. Touch and step voltages are measured to evaluate the performances of grounding systems. Dangerous voltages have been largely studied by the power frequency fault currents, on the other hand, the ground current containing the high frequency components and surge currents haven"t been considered. Many attempts about the grounding impedances reported in these days show that the performance of the grounding systems in high frequency range is very different with the ground resistance. It is necessary to analyze the dangerous voltages formed by the ground currents containing high frequency components. In this paper, the ground surface potential rises near the vertical and horizontal grounding electrodes are measured at the frequency of 100[Hz], 30[kHz], and 100[kHz]. Dangerous voltages are investigated with the frequency-dependent grounding impedance. As a result, the ground surface potential rise is increased as the grounding impedance increases. Touch and step voltages near the grounding electrode whose impedance increases with the frequency are sharply raised. |