Very fast electromagnetic transients in air insulated substations and gas insulated substations due to disconnector switching

Very fast electromagnetic transients (VFT) in air insulated substations (AIS) and gas insulated substations (GIS) caused by switching operation of disconnectors are investigated. Results obtained from very extensive field tests and from digital simulations as well as a comparison between field tests and calculation results of VFT in AIS and GIS due to disconnector switching are presented. Field tests of disconnector switching in 220 kV air insulated substations Grabovica and Kakanj as well as test circuit of 110 kV GIS section are performed. Digital simulation of VFT for different models of power network are performed using EMTP-ATP.