Development of 420 kV gas insulated switchgear with one–break spring operated gas circuit breaker

Reduction of life-cycle cost of high-voltage electric equipment including installation and maintenance costs is an increasing need for electric power utilities. In general, gas insulated switchgear (GIS), which is one of the high-voltage electric equipment, should be compact and have high-reliability that enables the reduction of installation period and maintenance work. 420 kV GIS with one-break spring operated gas circuit breaker (GCB) has been developed to meet the growing demand for substation construction together with the demand for reduced installation and maintenance costs. The paper presents key benefits and their supporting technologies applied to the developed GIS.