What is GIS (Gas Insulated Switchgear)

Answer Posted / hanupowergrid

It is very much required to establish an electrical substation at load center. Since, establishing a substation at load center is quite economical and profitable in many aspects. As it reduces length of feeders and due to short length feeders, the quality of voltage regulation improves. But the main obstruction of establishing a substation at load center is space. Generally main load center of any place is situated at very congested place where, sufficient land for establishing conventional electrical substation is very hardly available.

his problem can be solved by using gas insulated switchgear technology. In this type of switchgear, all the necessary components of switchgear can be assembled in very limited space. GIS is a kind of metal enclosed switchgear. That means, all the equipments of the electrical switchgear are enclosed by gas tight metal enclosure and SF6 gas is used as insulation between live parts of the equipments and earthed metal enclosure. This type of switchgear, means, gas insulated switchgear is available from 12 KV system to 800 KV system. For establishing electrical substation in very limited place this type of SF6 insulated electrical switchgear plays the major role.

Gas insulated components of substation are generally,

Electrical bus bars.

Electrical isolators or disconnectors.

Circuit breakers.

Current transformers.

Voltage transformers.

Earth switches.

Surge arrestors or lightning arresters.

The substation, assembled by gas insulated switchgear, is popularly known as gas insulated metal enclosed substation (GIMES). GIMES technology is not very recent invention, it is successfully running for over thirty years. In gas insulated medium voltage switchgear, vacuum technology is used as interrupting purpose and SF6 gas is used as insulation material. Although for both interruption and insulation, SF6 gas is used in many medium voltage GIS system. But for such equipments rated SF6 gas pressures are different for interruption and insulation. SF6 gas pressure for insulating purpose is generally kept below 2.5 bar whereas SF6 gas pressure for interrupting purpose is ranged from 5 bar to 7 bar. As vacuum technology is not available for high voltage, so for GIS or gas insulated switchgear system above 72.5 KV, only SF6 is used both for interruption medium and insulation. There are different types of gas insulated metal enclosed switchgears available depending upon their constructional feature.

Is This Answer Correct ?    2 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

ow can i get certificate of competency as electrical supervisor and my diploma in electrical engineering from jalgaon.

1865


What is the differance between 2 dc motors of armature voltage 660 v and 440 v?

1553


What happen when neutral point connected to core balance current transformer? (Neutral point of an alternator of a 180KVA DG. Neutral point connected to CBCT means enter to the CBCT)

1839


Do closed loops systems require manual input?

638


Motor,transformers,capacitor tubelight etc....

1212






State The Difference Between Generator And Alternator?

667


i want to put single phase load on scott connected transformer,eventhough how to balance the transformer.

1412


Which device of PlC does share load between DG sets when DG are running in perallel?

1553


what questions will be asked for 11/33KV licence interview APSEB hyderabad. Can any one share question and answers.

17399


what is resver in electrical enginnering with answer

1202


A 11KV, 1200 A breaker combination fixed in a cubicle for HT motor.Is normally for 11 KV motor fuse is using? if Yes, What range fuse is required?

1519


How generator NPS(NEGATIVE PHASE SEQUENCE TEST)TEST WAS DONE? PROCEDURE WITH DETAILS?

1724


briefly explain principle of resistance welding

1413


What is meant by analogous system?

764


What will happen if the d.c. Shunt motor opened accidentally running on no-load has its shunt field winding?

885