| 摘要 |
PURPOSE:To boost the corona discharge starting voltage itself by suppressing emission of electrons from a locally concentrated field part in a gas insulated electric apparatus. CONSTITUTION:Insulating mixture gas 20 is encapsulated, at full pressure of 1.4 atmospheric pressure or higher, in a gas insulated electric apparatus comprising a conductor 3 to be applied with high voltage, and a metallic foreign matter 7 or a triple junction 8 existing in a grounded metallic enclosure 1 for containing an insulating spacer 4 which supports the conductor 3 and the electric field concentrates locally thereat. Partial pressure of SF6 gas is set at 1 atmospheric pressure or higher with the partial pressure ratio being set at 70% or lower and nitrogen gas N2, dry air or carbon dioxide CO2 is employed as a second gas contained in the insulating mixture gas 20. Total number of electrons at the tip of electron avalanche can be reduced drastically by regulating the full pressure of the encapsulated mixture gas and the partial pressure ratio of SF6 gas. |
