| 摘要 |
PROBLEM TO BE SOLVED: To suppress charge influx from a ground tank to a metal foreign object, while suppressing partial discharge on the periphery of the metal foreign object, even if the metal foreign object is deviated positionally when the ground tank of a gas-insulated switchgear vibrated.SOLUTION: A gas-insulated switchgear includes a ground tank 2 filled with insulation gas, a central conductor 3 arranged in the ground tank 2 and applied with a voltage, a high-resistance insulation 5 arranged on the inner surface on the lower side of the ground tank 2, and composed of an insulation material of high resistivity, and a low resistance insulation 6 arranged on at least a partial surface of the high-resistance insulation, and composed of a low resistivity material. A time constant represented by multiplication of the electrical resistivity of the low resistance insulation 6, the relative permittivity of the low resistance insulation 6, and the permittivity of vacuum is set smaller than the discharge delay time until partial discharge is generated in a metal foreign object 7 mixed into the ground tank 2.SELECTED DRAWING: Figure 1 |
