High-Speed Earthing Switch in Gasinsulated Metal-Enclosed Switchgear

A high-speed earthing switch (HSES) can be permanently installed in the switching apparatus in gas-insulated metal-enclosed switchgear (GIS). A new spring-drive driven HSES has been developed and tested in one-phase and three-phase synthetic test circuits. The USES rated voltages, 245 kV and 300 kV, enabled closing (making) operation on the peak value of short-circuit current of 100 kA two times without maintenance, was used. This article presents the main task of HSES at application in GIS, design characteristics, and two different test procedures. Wide searching throughout standards was performed in order to define the real status of this apparatus.