Vacuum switchgear

A Greenwood, Vacuum Switchgear, Institution of Electrical Engineers, 1994. 

Blower, R.W., Cornick, K.J. and Reece, M.P. Use of vacuum switchgear for the control of motors and transformers in industrial systems. Electric Power Appliciitions. 2. No. 3. June(1979)... 

Switchgear is frequently described by the medium used in the interrupting device and method of mounting. The principal types of medium presently in operation are bulk oil, minimum oil, air, sulfur hexafluoride gas (SFg) and vacuum. The most common mounts for indoor industrial switchgear are cubicle and metal clad. The main features of and the perceived advantages and disadvantages of the different types of medium are reviewed below, while international standards applicable to switchgear are listed in Table 16.2. 

The primary switchgear is Powell metal-clad 4-bay switchgear that uses vacuum breakers for generator output and primary utility feed and contains generator and utility protective relays as well as synchronizing controls for generator/utility grid interconnect. 

The switchgear where PT was connected was of kind of metal-enclosed and was composed of 11 panels of 13.8 kV with a current capacity of 2,000 A. Nine of the panels were vacuum switches with their auxiliary equipment. One of the panels was used exclusively for measurement. The remaining panels, was empty because it could not be restored after the failure of one of the PT s occurred three years ago. One of the feeders of the switchgear was connected to one of the generators of the plant. 

Use air-insulated, vacuum or SFe-insulated switchgear and control gear instead of oil-insulated equipment. 

Another precaution against the risks associated with the use of oil-filled switchgear is to replace it with switchgear that uses an alternative insulating medium. Options include sulphur hexafluoride (SFe) gas-filled enclosures, air insulation, and vacuum circuit breakers. The SFe variety is beginning to lose favour because of the environmental and toxic hazards that the gas poses, so vacuum and air-insulated gear is now preferred by most high... 

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