Field tests on current carrying performances of 1000 kV GIS

Field tests on 1000 kV (UHV) gas insulated switchgear (GIS) substation equipment have been conducted. This paper presents mainly the results of a temperature rise test which demonstrates the mechanical reliability of the GIS. The specified value of induced current of the enclosure and shunt bars among phases is set as much as 100% of rated normal current. The average temperature of four points defined on GIS enclosure surface is adopted as the base temperature for evaluation of thermal expansion and thermal stress of the enclosure. The limit of temperature rise for the GIS enclosure is as high as 65 K according to the revised specification.