Title :
Transient impedance of GIS grounding grid
Author :
Karaki, S. ; Yamazaki, T. ; Nojima, K. ; Yokota, T. ; Murase, H. ; Takahashi, H. ; Kojima, S.
Author_Institution :
Tokyo Electr. Power Co. Inc., Japan
fDate :
4/1/1995 12:00:00 AM
Abstract :
The transient impedance of a grounding grid for a commercial 550 kV gas-insulated substation (GIS) was measured on site using steep front currents with rise time from 100 ns to 2 μs. From the measured results, it was found that the transient impedance of the measured grid for those currents is simulated by a series circuit with an inductance 1 μH and a resistance 3 Ω. Applying the obtained impedance to the lightning surge analysis, it is pointed out that the grounding condition at an arrester tank end has a remarkable influence on the protecting performance of a surge arrester
Keywords :
arresters; digital simulation; earthing; electric impedance; equivalent circuits; gas insulated substations; lightning protection; power system analysis computing; power system measurement; power system protection; software packages; 100 ns to 2 mus; 3 ohm; 550 kV; EMTP; GIS; arrester tank end; computer simulation; gas-insulated substation; grounding grid; inductance; lightning surge analysis; performance; power systems; protection; resistance; rise time; series circuit; steep front currents; surge arrester; transient impedance; Arresters; Current measurement; Electrical resistance measurement; Geographic Information Systems; Grounding; Impedance measurement; Inductance measurement; Substations; Surge protection; Time measurement;
Journal_Title :
Power Delivery, IEEE Transactions on
