What is insulated switchgear?
Gas-insulated high-voltage switchgear (GIS) is a compact metal encapsulated switchgear consisting of high-voltage components such as circuit-breakers and disconnectors, which can be safely operated in confined spaces.
What is gas insulated substation GIS?
A gas insulated substation (GIS) is a high voltage substation in which the major conducting structures are contained within a sealed environment with a dielectric gas known as SF6, or sulfur hexafluoride gas as the insulating medium.
What is the use of gas insulated substation?
SF6 has two to three times the insulating ability of air at the same pressure. SF6 is about 100 times better than air for interrupting arcs. It is the universally used interrupting medium for high voltage circuit breakers, replacing the older mediums of oil and air.
What is gas insulated substation PPT?
3 Introduction Gas Insulated Substation (GIS) is a compact, multicomponent assembly enclosed in a ground metallic housing in which the primary insulating medium is compressed SF6 gas. …
Why is switchgear gas insulated?
Gas-insulated switchgear saves space compared with air-insulated equipment, although the equipment cost is higher. Oil insulated switchgear presents an oil spill hazard. Switches may be manually operated or have motor drives to allow for remote control.
What is meant by switchgear?
Switchgear is a general term used to refer to a range of switches, circuit breakers, fuses, etc., which are used in an electric power system to control, regulate and switch the circuit on and off.
What is air insulated substation?
An air-insulated substation (AIS) is one where the main circuit potential is insulated from the ground by air using porcelain or composite insulators and/or bushings. AIS is the most common type of substation, accounting for more than 70% of substations all over the world.
What is the purpose of HV switchgear?
HV transmission switchgear is used within substations to control the flow of large quantities of electric power within an electrical network. It may operate at rated voltages of 145–800 kV, with normal load currents of up to 4 kA and short-circuit currents of up to 80 kA.
