Mathematical Investigation of the Transient Overvoltages During Disconnector Switching in Gis

This paper investigates the influence of some parameters on the magnitude of the transient overvoltages after disconnector restrike. In case of open-ended GIS the transient overvoltage consists of rectangular pulses due to strictly odd-numbered harmonics. In case of lumped capacitances in the GIS this strict order within the harmonics is changed, which results in higher overvoltages. A large capacitor to ground was found to yield the highest overvoltages.