66/77kV C-GIS Using Composite Insulation in SF₆ Gas

Abstract

High-voltage SF₆ gas-insulated switchgear was at first introduced as a power supply facility.
As its reliability and safety come to be recognized in service, the gas-insulated switchgear has evolved into a power receiving facility. This switchgear consists of a cubicle enclosure sealed with a low pressure SF₆ insulating gas and a long-life vacuum circuit breaker installed therein with devices and circuits integrated at higher density, the switchgear has achieved a substantial volume reduction of some 50% from the conventional one.
This paper introduced fundamental technologies such as low-pressure SF₆ gas insulation, gas-solid composite insulation and gas monitoring, and also gas-insulated vacuum switchgear for 66/77kV power receiving facilities.