Posts: 1,061
Threads: 613
Joined: Feb 2010
[attachment=2362]
INTRODUCTION
Composed of pipes that houses conductors in SF6
Invented in 1974
Both overhead & underground system
Drawbacks of XLPE lead to GIL
Most economic, environment friendly & maintenance free alternative
WHY GIL
Installation expense is less
XLPE needs extra cooling arrangement
Allowed conductors to be larger in cross-section
Construction of large capacity transmission link
SUPERIOR PROPERTIES OF SF6 GAS
High dielectric strength at lower cost
Regeneration capacity following a breakdown
Low pressure-increase following a breakdown
High load transfer capacity
INSTALLATION
Ground level
Elevated above ground
Below grade in an open or covered trench
Directly buried underground
Vertically in tunnels, shafts or towers
Suspended from existing substation structures
MAIN COMPONENTS
Conductors & enclosures
Insulators & particle traps
Plug in contacts
Aluminum bellows
Enclosure joints
HOW TO REDUCE THE COST OF GIL
Standardization of components
Optimization of pipeline
Introduction of N2
ADVANTAGES OF SF6-N2 MIXTURE
Less harm to atmosphere
Reduced cost for GIL
Useful for long distance power transmission
Insulating property is improved
H-GIL
Large capacity.
For long distance power transmission line.
Structure between that of GIL & XLPE.
Uses 3 sub-conductors.
Covered with solid dielectric polyethylene.
Insulated with SF6.
More flexible.
Withstands voltage same or more than GIL.
ADVANTAGES
High current carrying capacity
Limited working space
High efficiency
Low resistive & capacitive loss
Good appearance
No interference with communication circuits
No extra cooling is required
High reliability
DISADVANTAGES
Length of is each GIL section is limited.
Particle contamination lower the insulating reliability of GIL.
Breakdown of insulator.
Earthquake resistant design must be considered.
SF6 gas is harmful to ozone.
APPLICATIONS
Installation in tunnels
Ideal for environments that are sensitive to electro-magnetic fields.
Suitable for metropolitan areas where high energy rate is required.
Well suited for high power transmission.
CONCLUSION
One of the best transmission system in the world
Safe and reliable for more than 20 years
Researches are still going on to improve efficiency
Posts: 1
Threads: 0
Joined: Aug 2010
sir ,with due respect it is to state that i am not getting full report and ppt of GIS please plz send me the thread regarding this seminar plz
thank you so much in adv.
Posts: 5,362
Threads: 2,998
Joined: Feb 2011
superior technology and excellentknowhow ensure quality and reliability
Siemens GIL systems are based on thesuccessful SF6 tubular conductor technology,which has been around for severaldecades. GIL consist of a central aluminumconductor with a typical electrical crosssection of up to 5,300 mm2. The conductorrests on cast resin insulators, which centerit within the outer enclosure. This enclosureis formed by a sturdy aluminum tube,which provides a solid mechanical andelectrotechnical containment for the system.To meet up-to-date environmentaland technical aspects, GIL are filled withan insulating gas mixture of mainly nitrogenand a smaller percentage of SF6. Forincreased lifetime, the “performance line”product series has a longitudinal particletrap installed over the entire horizontalroute section. An automated orbitalwelding procedure, accompanied bytailored ultrasonic inspection techniques,ensures perfect gastightnessof the aluminum tubes.During service, the fully encapsulateddesign fully protects the GIL againstenvironmental influences. Thanks to thetechnologically clear-cut, logical designand the use of high-quality materials,an absolutely maintenance-free productis achieved which requires externalinspection only. And at the end of itsservice life, the issue of de-installationis solved. The GIL tubular system withall its components and the insulationgas mixture are 100 percent recyclable.These factors help to minimize lifetimecosts.
Impressive practical record: GIL systemin Germany’s Wehr power plant
Siemens installed a GIL in a tunnel inthe Wehr pumped-storage power stationin the Black Forest as long ago as 1975.With a single-phase length of almost 4 kmthis installation is still a significant referenceamong worldwide GIL projects. Notwithstandingits service time, an inspectionafter 30 years showed that all componentswere still in top condition, and assuredthe customer that GIL will provide manymore years of reliable operation.
download full report
http://energy.siemenshq/pool/hq/power-tr.../GIL_e.pdf
Posts: 1
Threads: 0
Joined: Jan 2012
pls send me thic presentation which will helps me alot.......
Posts: 6,566
Threads: 1,107
Joined: Jul 2011
Posts: 7,939
Threads: 421
Joined: Jun 2012
