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 problem...

Gas Insulated Switchgear (GIS) has been widely used in substations. The insulating medium used in GIS is sulfur hexafluoride (SF6) gas. However, the internal insulation defect existed in GIS would inevitably lead to partial discharge (PD), and cause the composition of SF6 to SOF2, SO2F2 and SO2 and other characteristic component gases. The decomposition phenomenon would greatly reduce the insul...

Latent insulation defects introduced in manufacturing process of gas-insulated switchgears can lead to partial discharge during long-time operation, even to insulation fault if partial discharge develops further. Monitoring of decomposed components of SF₆, insulating medium of gas-insulated switchgear, is a feasible method of early-warning to avoid the occurrence of sudden fault. Polyaniline th...

OVERVIEW: Hitachi has developed smaller and more reliable gas-insulated switchgear (GIS) in response to demands for lower costs and stable power supplies. Reliability of this GIS was improved and the enclosure diameter was reduced in order to minimize the installation space by using new analysis techniques and rationalization in insulation design and in temperature rise criteria. Furthermore, t...