Comparative Analysis of Transients in AIS and GIS With Vacuum Interrupters

Gas-insulated switchgear (GIS), at the medium voltage (MV) level, uses vacuum interrupters for current interruption. They are as compact as GIS while retaining the superior performance of vacuum interrupters. The presence of SF6 influences the transient behavior of the system. As the use of GIS with vacuum interrupters becomes rampant, the knowledge of differential transient behavior is critical for proper application. This article presents a comparative study of the transients in GIS and air-insulated switchgear (AIS) with vacuum interrupters, through simulation and observations during testing of switchgear.