Experimental Study on the Relationship between Transient Enclosure Voltage and Very Fast Transient Overvoltage

Transient enclosure voltage (TEV), generated during gas insulated switchgear (GIS) disconnector operations, may raise the issue of shock hazard and electromagnetic interference to secondary equipment. Malfunctions of SF6 gas density relay caused by TEV have been reported in switching tests of ultra-high voltage substation in China. Previous studies generally defined TEV as the voltage wave which is created by the voltage collapse across disconnector contacts at striking, then propagates on the enclosure, and regarded it as a special case of very fast transient overvoltage (VFTO). However, whether there is a quantitative relationship between TEV and VFTO is still controversial. Moreover, less work has been done on TEV experimental study compared with modelling and simulation study, because…