Analysis of effective factors on transient ground potential rise in gas insulated substations

This study presents the manner in which transient modeling concepts, which are fully analyzed in the referred standards, are implemented, for the purpose of evaluating the Transient Ground Potential Rise (TGPR). This is a phenomenon of 10–100kV voltages with up to 10µs duration on the grounded enclosure of Gas Insulated Substations (GIS), which may cause concern for personnel safety and problems for protection and control circuits in substations. This article summarizes the results of the investigation for influential factors on TGPR, such as, different contingency conditions and grounding system models. This article focuses on the TGPR study of "Siah-bishe" 400kV gas insulated substation. The study was carried out by modeling all pieces of equipment in the ElectroMagnetic Transients Program (EMTP)-RV, with careful consideration of different modeling guidelines and instructions described in the available standards.