gas insulated substation full report
Thread Rating:
  • 1 Vote(s) - 2 Average
  • 1
  • 2
  • 3
  • 4
  • 5
project report tiger
Active In SP
**

Posts: 1,062
Joined: Feb 2010
#1
19-02-2010, 11:46 AM



.pptx   GAS INSULATED SUBSTATION.pptx (Size: 4.78 MB / Downloads: 2,714)

GAS INSULATED SUBSTATION

INTRODUCTION

Conventional substations requires, small installation size, protection against atmospheric pollution and moisture, noiseless operation, nonexplosive and flame resistant, reduced maintenance, minimal radio interference, but totally enclosed substations using SF6 gas as insulation that are also known as GIS is now in widespread use in the electrical power industry .
It consist of
¢ Bus bars
¢ Circuit breakers
¢ Disconnecting switches
¢ Earthing switches
¢ Current transformers
¢ Voltage transformers
¢ Densimeter
¢ Cable and boxes
¢ Gas supply and gas monitoring equipment
¢ Local control

Circuit Breaker

Under short circuit conditions, however, the current may reach tens of thousands of amperes at a power factor as low as 0.1. It is duty of a circuit breaker to interrupt such currents as soon as possible to avoid equipment damage.

Disconnectors

¢ Disconnectors or isolators are used for electrical isolation of circuit parts
¢ They are slow acting and operating at off load
¢ Disconnectors must be carefully designed and tested to be able to break small charging current without generating too-high over voltage,

Local Control Cubicles LCC

LCC is the interface cubicles to all secondary systems of a substation which are represent a station control and protection.
LCC includes control and alarm functions as well as the correct distribution of auxiliary power supply for the relevant GIS bay.

Earthing Switch

Slow-operating earthing switch are used for protection purpose when work is being done in the substation, but are operated only when it is certain that the high-voltage system is not energized. The fast-closing earthing switch can close against full voltage and short circuit power. The high speed earthing switch is achieved by means of a spring-closing device.

Voltage Transformer

Variable location on feeder and busbars.
¢ Integrated disconnecting facility for GIS and power cable testing without dismantling and gas handling.
¢ Flexible gas compartment allocation for optimal service oriented gas supervision.

Current Transformer

¢in the single phase enclosed Core of CT is located outside the enclosure$inside for three phase
¢ Gas compartment to reduce access of moisture and to suppress gas-tight bushings for secondary connections.

Cables Compartment

1. Optimized solution for plug-in type power cable connection.
2. Adjustable support structures for minimum requirements for the GIS floor.
3. Fixation to the GIS floor by cemented anchor bolts, no need for special foundation (steel beams¦.etc)

PROPERTIES OF SF6


¢ SF6 does not harm to
the ozone layer.
¢ Sf6 gas is chemically stable
¢ Non poisonous
¢ Colourless&heavier than air
¢ Almost water insoluble
¢ Non inflammable

ADVANTAGES

¢ Gis have no risks for fire&explosion due to leakage of oil
¢ They generate no noise&have no radio interference
¢ Located closure to load centers there by reducing transmission&distribution s\ms
¢ It offer solutions including
-In industrial areas where space&pollution problems
-Mountain areas where ice&snow are major problems

DISADVANTAGES

GIS installations tend to be much more expensive that air-insulated installations with the same rating.
VFTO during switching operations or earth faults and transient enclosure voltages and particle contamination

APPLICATIONS

¢ High voltage installations (above 115kv)
¢ Urban installations
¢ Indoor installations

GAS INSULATED TRANSFORMER

Use SF6 Gas as the insulating and cooling medium instead of insulating oil.
First units produced in 1967.
Transformer applications: Distribution class units up to 400 MVA, 345 kV.
¢Primarily used in substations located in urban areas (including inside buildings, underground) due to safety benefits.

GAS INSULATED SWITCH GEAR

The space occupied by switch gear is greatly reduced
Totally unaffected by atmospheric conditions
Provides high degree of operational reliability
Easier to install in difficult site conditions

GAS INSULATED SHUNT REACTOR

Features
¢ Suitable for installation
¢ Excellent history of reliability and safety
¢ Fine radial core
¢ Circular yoke and circular tank
¢ Low loss
¢ Easy maintenance
Manufacturing Range
¢ Voltage-13.8 ~ 138kV
¢ Frequency-50 or 60Hz
¢ Capacity-5 ~ 60Mvar

FUTURE TRENDS IN GAS INSULATED SUBSTATIONS

Compact design of switch gear by using three phase modules
Use of vacuum circuit breaker cells in the medium high voltage GIS and fewer brakes per pole in high voltage circuit breakers
Optimization of GIS design to allow easier maintenance

CONCLUSION

GIS are necessary for EHV&UHV and some important areas to be studied include more conservative designs better particle control&improved gas handling&decomposition product management techniques
Achieving&maintaining high levels of availability requires a more integrated approach to quality control by both users and manufactures
Reply
dineshyepuru
Active In SP
**

Posts: 1
Joined: Mar 2010
#2
02-03-2010, 01:38 PM

THNK U
Reply
project topics
Active In SP
**

Posts: 2,492
Joined: Mar 2010
#3
21-04-2010, 03:39 PM


.doc   Gas Insulated Substation.doc (Size: 54.5 KB / Downloads: 761)

Gas Insulated Substation
Gas Insulated Substations(GIS) is a compact, multicomponent assembly enclosed in a ground metallic housing which the primary insulating medium is compressed sulphur hexaflouride(SF6) gas. It generally consists components Of
a) Bus bars
b) Circuit Breakers
c) Disconnecting switches
d) Earthing switches
e) Current transformers
f) Voltage transformers
g) Cable and boxes
h) Gas supply and gas monitoring equipment
i) Densimeters and
j) Local control
Why we need GIS1) Gas insulated Substations have found a broad range applications in power systems over the last three decades because of their high reliability Easy maintenance, small ground space requirements etc.,. 2) In our country also few GIS units have been in operation and a large number of units are under various stages of installation. 3) Although GIS has been in operation in several years, some of the problems are needful attention4) These problems include VFTO during switching operations or earth faults and transient enclosure voltages and particle contamination.
Advantages of GIS:
a) Because of the entire equipment being enclosed in enclosures, filled with pressurized SF6 gas, installation is not subject to environmental pollutions, as experienced along coastal areas or certain types of industries. b) Such installations are preferred in cosmopolitan cities, industrial townships, etc., where cost of land isveryhighand higher cost of SF6 insulated switchgear is justified by saving due to reduction in floor area requirement. It is not necessary that high voltage or extra high voltage switchgear to be installed out doors. c) Since most of the construction is modular and the assembly is done in the works, one site erection time both for supporting structures and switchgear is greatly reduced.

Disadvantages with Air Insulated Substations:
a) It requires huge amount of area .
b) Each and every component of substation is exposed to air and pollution.
c) Particularly in coastal area all the insulators are exposed to air and saline contamination.
d) Frequent flashovers and breakdown occurs.
e) Maintenance cost is more.
f) Installation time is also more.
g) More concrete work is necessary.

A) The necessity of this study :
Extremely high dielectric properties of SF6 have long been recognized. Compressed SF6 has been used as an insulating medium as well as arc quenching medium in electrical apparatus in a wide range of voltages.
Gas Insulated Substations (GIS) can be used for longer times without any periodical inspections. Conducting contamination (i.e. aluminum, copper and silver particles) could, however, seriously reduce the dielectric strength of gas-insulated system
B) The origin of these particles :
Metallic particles in GIS have their origin mainly from the manufacturing process or they may originate from moving parts of the system, such as breakers and disconnectors.
Metallic particles can be either free to move in the GIS or they may be stuck either to an energized electrode or to an insulator surface (spacer, bushing etc.). 1) Different metallic contamination viz Cu, Al and Ag have been considered for the above study. Typically a GIB of inner and outer dia 102/292mm have been considered for a 245KV system. used for simulation. Co-efficient of restitution and pressure have been varied from 0.1 to 0.9 and 0.1Mpa to 1Mpa respectively. 3) Typical results show that for a variation of copper particles of radii from 0.2 to 5mm, the maximum radial movement reduces from 6mm to 1mm. 4) Whereas in the case of variation of length from 1mm to 16mm the radial movement increases from 1mm to 9.8mm. With the change of pressure the movement is found to be almost same for majority of particles consider If a metallic particle crosses the gap and comes into contact with the inner electrode or if a metallic particle adheres to the inner conductor, the particle will act as protrusion on the surface of the electrode, and the voltage required for breakdown of the GIS will be dramatically decreased.
A metallic particle stuck on an insulator surface in a GIS will also cause a significant reduction of the breakdown voltage
Depending on the shape of the particles, as well as the geometry and voltage levels of the system, the particles get more or less influenced by the electric field which, in turn, makes them hazardous to the electrical system, in terms of partial discharges and breakdown.
1. The introduction of SF6 gas has revolutionized not only the technology of circuit breakers but also the layout of substations. 2. The dielectric strength of SF6 gas at atmospheric pressure is approximately three times that of air. 3. It is incombustible, non toxic, colourless and chemically inert. 4. It has arc-quenching properties 3 to 4 times better than air at equal pressure. 5. This enables the substation to be laid in a much lesser space.
6. Space requirement is only 10 to 25 percent of what is required is a conventional substation. 7. Thus where creation of a substation becomes necessary but adequate space is not available, such as in big cities or otherwise highly populated areas, GIS is the solution
reference:
ayyarao.blog.co.in
google.com
wikipedia.com
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
project topics
Active In SP
**

Posts: 2,492
Joined: Mar 2010
#4
23-04-2010, 02:43 PM


.pdf   gas insulated substation presentation.pdf (Size: 764.73 KB / Downloads: 814)

Design Features

GIS technology: compact, low-life cycle cost and
modular for indoor and outdoor applications
Modular design, factory pre-assembled and tested units
Space requirement less than 20 % of comparable AIS
Safety (enclosed energized components)
Continous monitoring of SF6 densitity
Sealed for operating life > 50 years
Major inspection: not before 25 years 1)
GIS Pressure Systems
Closed pressure systems:
The closed pressure system uses isolated

apparatus compartments with o-ring

sealed bolted flanges.
The tightness characteristic of a closed

pressure system stated by the

manufacturer shall be consistent with a

minimum maintenance and inspection

philosophy.
The leakage rate from any single

compartment of GIS to atmosphere and

between compartments shall not exceed

0.5 % per year for the service life of

the equipment.*
Practical experiences to the today's

design of GIS show as low as 0.2 % per

year.
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
scorpiongeo
Active In SP
**

Posts: 1
Joined: Apr 2010
#5
27-04-2010, 09:24 AM

Huge thanks, helped a lot
Reply
kavehjee
Active In SP
**

Posts: 1
Joined: Apr 2010
#6
12-05-2010, 12:05 PM

hi i have a seminar and presentation in my distribution system and i have emergency information from Gas insulated susbstation specially distribution substation
please help me
Sad
my mail : kavehjee@yahoo.com
Reply
Sidewinder
Active In SP
**

Posts: 171
Joined: May 2010
#7
15-05-2010, 08:37 PM

Hey ,
I didn't understand you. Is it that you need report on distribution system? Or is it that you want more info on gas insulated substations?
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
computer science topics
Active In SP
**

Posts: 610
Joined: Jun 2010
#8
28-06-2010, 05:49 PM


.zip   GAS INSULATED SUBSTATION.zip (Size: 5.45 MB / Downloads: 368)
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
projectsofme
Active In SP
**

Posts: 1,124
Joined: Jun 2010
#9
16-10-2010, 09:41 AM


.pptx   Single Phase and three Phase Distribution Substation.pptx (Size: 5.65 MB / Downloads: 178)
This article is presented by:
P. Ashis Ku. Patra
Single Phase and three Phase Distribution Substation


Introduction:


* Requirement of Substation
* What is a Substation

Classification:
1. In accordance with the service
a. Static
b. Converting
2. In accordance with the service voltage
a. Extra high voltage transmission Substation
b. Step-down or Distribution Substation
c. Industrial Substation
d. Substation for power factor correction

3. In accordance with mounting
a. Pole-mounted Substation
b. Foundation-mounted Substation
Single phase Distribution Substation

Ratings:
25 kVA
11/0.433 kV
1.31/33.34 Amp
Delta-Star Core type transformer
% impedance voltage=4


Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#10
10-03-2011, 09:55 AM


.docx   INTRODUCTION.docx (Size: 14.07 KB / Downloads: 125)
INTRODUCTION
Conventional substations requires, small installation size, protection against atmospheric pollution and moisture, noiseless operation, nonexplosive and flame resistant, reduced maintenance, minimal radio interference, but totally enclosed substations using SF6 gas as insulation that are also known as GIS is now in widespread use in the electrical power industry .
It consist of :
It consist of Bus bars Circuit breakers Disconnecting switches Earthing switches Current transformers Voltage transformers Densimeter Cable and boxes Gas supply and gas monitoring equipment Local control
Circuit Breaker :
Circuit Breaker Under short circuit conditions, however, the current may reach tens of thousands of amperes at a power factor as low as 0.1. It is duty of a circuit breaker to interrupt such currents as soon as possible to avoid equipment damage.
Disconnectors :
Disconnectors Disconnectors or isolators are used for electrical isolation of circuit parts They are slow acting and operating at off load Disconnectors must be carefully designed and tested to be able to break small charging current without generating too-high over voltage,
Local Control Cubicles “LCC” :
Local Control Cubicles “LCC” LCC is the interface cubicles to all secondary systems of a substation which are represent a station control and protection. LCC includes control and alarm functions as well as the correct distribution of auxiliary power supply for the relevant GIS bay.
Earthing Switch :
Earthing Switch Slow-operating earthing switch are used for protection purpose when work is being done in the substation, but are operated only when it is certain that the high-voltage system is not energized. The fast-closing earthing switch can close against full voltage and short circuit power. The high speed earthing switch is achieved by means of a spring-closing device.
Voltage Transformer :
Voltage Transformer Variable location on feeder and busbars. Integrated disconnecting facility for GIS and power cable testing without dismantling and gas handling.• Flexible gas compartment allocation for optimal service oriented gas supervision.•
Current Transformer :
Current Transformer in the single phase enclosed Core of• CT is located outside the enclosure$inside for three phase Gas compartment to reduce access of moisture and to suppress gas-tight bushings for secondary connections.•
Cables Compartment :
Cables Compartment 1. Optimized solution for plug-in type power cable connection. 2. Adjustable support structures for minimum requirements for the GIS floor. 3. Fixation to the GIS floor by cemented anchor bolts, no need for special foundation (steel beams….etc)
PROPERTIES OF SF6 :
PROPERTIES OF SF6 SF6 does not harm to the ozone layer. Sf6 gas is chemically stable Non poisonous Colourless&heavier than air Almost water insoluble Non inflammable
ADVANTAGES :
ADVANTAGES Gis have no risks for fire&explosion due to leakage of oil They generate no noise&have no radio interference Located closure to load centers there by reducing transmission&distribution s\ms It offer solutions including -In industrial areas where space&pollution problems -Mountain areas where ice&snow are major problems
DISADVANTAGES :
DISADVANTAGES GIS installations tend to be much more expensive that air-insulated installations with the same rating. VFTO during switching operations or earth faults and transient enclosure voltages and particle contamination
APPLICATIONS :
APPLICATIONS High voltage installations (above 115kv) Urban installations Indoor installations
Comparison b\w gis&ais :
LAY OUT OF GIS :
GAS INSULATED TRANSFORMER :
GAS INSULATED TRANSFORMER Use SF6 Gas as the insulating and cooling medium instead of insulating oil. First units produced in 1967. Transformer applications: Distribution class units up to 400 MVA, 345 kV. •Primarily used in substations located in urban areas (including inside buildings, underground) due to safety benefits.
GAS INSULATED SWITCH GEAR :
GAS INSULATED SWITCH GEAR The space occupied by switch gear is greatly reduced Totally unaffected by atmospheric conditions Provides high degree of operational reliability Easier to install in difficult site conditions
GAS INSULATED SHUNT REACTOR :
GAS INSULATED SHUNT REACTOR Features Suitable for installation Excellent history of reliability and safety Fine radial core Circular yoke and circular tank Low loss Easy maintenance Manufacturing Range Voltage-13.8 ~ 138kV Frequency-50 or 60Hz Capacity-5 ~ 60Mvar
FUTURE TRENDS IN GAS INSULATED SUBSTATIONS :
FUTURE TRENDS IN GAS INSULATED SUBSTATIONS Compact design of switch gear by using three phase modules Use of vacuum circuit breaker cells in the medium high voltage GIS and fewer brakes per pole in high voltage circuit breakers Optimization of GIS design to allow easier maintenance
Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#11
11-03-2011, 04:21 PM

presented By :
Arupananda Pattanaik


.ppt   gis.ppt (Size: 2.08 MB / Downloads: 389)

.ppt   gis.ppt (Size: 2.08 MB / Downloads: 389)
GAS INSULATED SUBSTATION
Introduction

 It is a one type of switchgear.
 The term switchgear, used in association with the electric power system, or grid, refers to the combination of electrical disconnects.
There are 3 types of switchgear.i.e
1. AIS
2. HYBRIT GIS
 GIS
 Gas Insulated Substations (GIS) is a compact,multicomponent assembly enclosed in a ground metallic housing in which the primary insulating medium is compressedSulphur hexafluoride (SF6)gas.
 SF6acts as an insulation between live parts & the earthed metal closure.
 Gas insulated switchgear is used in industrial areas to fulfil high-energy demands by space saving design with a minimum of cost
 SF6 switchgear installed in Canada in a 550 kV substation with 100 kA
Comparison between AIS &GIS
AIS
 Air-insulated substation:- An electric power substation that has the busbars and equipment terminations generally open to air.
 It utilizes insulation properties of ambient air for insulation to ground.
 Very fast electromagnetic transients (VFT) in air insulated substations (AIS)
 Air Insulated Substation (AIS) makes it possible to install High Voltage substations that take-up less space
 These are more cost-efficient than conventionally designed outdoor infrastructures.
 Image of AIS
 Hybrid Gas Insulated Switchgear
 Small equipment cost.
 It takes less area.
 High reliability similar to GIS substation.
 Easy extension.
 It is a combination of AIS and GIS.
GIS
 Gas Insulated Substations (GIS) is a compact,multicomponent assembly enclosed in a ground metallic housing in which the primary insulating medium is compressedSulphur hexafluoride (SF6)gas.
 SF6acts as an insulation between live parts & the earthed metal closure.
 Gas insulated substations are particularly suitable for underground construction beneath public buildings.
 Gas insulated substation mainly used for a power transmission system or a sub-station system, of which outgoing bus bar is shortened to reduce consumption of the outgoing bus bar
Sulfur Hexafluoride
 A colorless, odorless, non-toxic, liquified gas. Shipped as a liquid under its own vapor pressure.
 Sulfur Hexafluoride gas, which is itself inert.
 It disassociates in the presence of an RF field to form reactive fluorine ions.
 SF6acts as an insulation between live parts & the earthed metal closure.
 The dielectric strength of SF6 gas at atmospheric pressure is approximately three times that of air.
 pace requirement is only 10 to 25 percent of what is required is a conventional substation.
 SF6 can be prepared from the elements through exposure of S8 to F2. This is also the method used by the discoverers Henri Moissan and Paul Lebeau in 1901
 It does not react with molten sodium, but reacts exothermically with lithium.
 Of the 8,000 tons of SF6 produced per year, most (6,000 tons) is used as a gaseous dielectric medium in the electrical industry,
 it has a much higher dielectric strength than air or dry nitrogen.
 This property makes it possible to significantly reduce the size of electrical gear.
Properties
 Molecular formula SF6
 Molar mass 146.06 g/mol,
 Density 6.164 g/L (gas, 1 bar)
1.329 g/ml (liquid, 25 °C)
2.510 g/cm3 (solid, −50.8 °C)
 Melting point- 50.7 °C (triple point)
 Boiling point− 64 °C (209 K) (subl.)
decomp. at ca. 500 °C (773 K)
 Solubility in waterslightly soluble
 Solubility in ethanolsoluble
 Specification of GIS
 The weight and size of the GIS equipment do not change appreciably with the voltage class.
 The additional insulation required for the next voltage class is achieved by increased gas density.
 Owing to these flexibilities, a few manufacturers offer the same equipment for two voltage classes (like 170/145 kV).
 Even when the GIS equipment is designed for an individual voltage class, the dimensions and weights of the equipment differ marginally.
Component of GIS
 Bus bars.
 Circuit Breakers.
 Disconnecting switches.
 Earthing switches.
 Current transformer.
 Voltage transformers.
 Cable and boxes.
 Gas supply and gas monitoring equipment.
Circuit Breakers
 A circuit breaker is an automatically-operated electrical switch designed to protect from damage caused by overload or short circuit.
 Its basic function is to detect a fault condition and, by interrupting continuity, to immediately discontinue electrical flow.
 Unlike a fuse, which operates once and then has to be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation.
 Current interruption in a high-voltage circuit-breaker is obtained by separating two contacts in a medium, such as SF6, having excellent dielectric and arc quenching properties.
 After contact separation, current is carried through an arc and the arc is interrupted & cooled by a gas blast of sufficient intensity.
Current transformer
 Current transformer (CT) is used for measurement of electric currents.
 Current transformers are also known as instrument transformers.
 Current transformers are commonly used in metering and protective relays in the electrical power industry.
Voltage transformers
 Voltage transformers (VTs), also referred to as “Potential transformers" (PTs), are used in high-voltage circuits.
 They are designed to present a negligible load to the supply being measured, to allow protective relay equipment to be operated at lower voltages, and to have a precise winding ratio for accurate metering
Disconnecting switches
 Disconnector switches are safety devices used to open or to close a circuit when there is no current through them.
 These are used to isolate a part of a circuit, a machine, a part of an overhead line or an underground line so that maintenance can be safely conducted.
 The opening of the line isolator or busbar section isolator is necessary for safety, but not sufficient.
 Life cycle cost AIS GIS
 Planning and engineering 100% 80%
 Real estate 100% 40%
 Primary equipment 100% 120%
 Secondary equipment 100% 100%
 Earthwork, civil work 100% 60%
 Electrical assembly 100% 70%
 Maintenance 100% 50%
 Outage 100% 50%
 Life cycle costs after 10 years 100% 70%
Reply
seminar addict
Super Moderator
******

Posts: 6,592
Joined: Jul 2011
#12
06-02-2012, 10:23 AM

to get information about the topic gas insulated transmission lines full report ,ppt and related topic refer the link bellow

topicideashow-to-gas-insulated-transmission-lines-full-report

topicideashow-to-gas-insulated-transmission-lines-in-railway-galleries?pid=64664#pid64664

topicideashow-to-gas-insulated-substation-full-report?page=3

topicideashow-to-gas-insulated-substation-full-report?pid=40017#pid40017

topicideashow-to-gas-insulated-substation-full-report?pid=27634
Reply
seminar paper
Active In SP
**

Posts: 6,455
Joined: Feb 2012
#13
07-03-2012, 11:05 AM

to get information about the topic gas insulated transmission lines full report ,ppt and related topic refer the link bellow

topicideashow-to-gas-insulated-transmission-lines-full-report

topicideashow-to-gas-insulated-transmission-lines-in-railway-galleries?pid=64664#pid64664

topicideashow-to-gas-insulated-substation-full-report?page=3

topicideashow-to-gas-insulated-substation-full-report?pid=40017#pid40017

topicideashow-to-gas-insulated-substation-full-report?pid=27634

Reply
seminar paper
Active In SP
**

Posts: 6,455
Joined: Feb 2012
#14
06-04-2012, 10:39 AM

Gas Insulated Substations Advantages Disadvantages


Gas Insulated Substations (GIS):
Gas Insulated Substations (GIS) are differ from Air Insulated Substations (substations we usually see) such that all the substation equipment such as busbars, circuit breakers, current transformer, potential transformers and other substation equipment are placed inside SF6 modules filled with SF6 gas. SF6 gas which has high dielectric property acts as insulating medium to the High Voltage or Extra High Voltage substation equipment. Generally Gas Insulted Substations (GIS) are indoor type as it requires 1/10th of the space required for conventional substations. Some of the advantages and disadvantages of Gas Insulated Substations (GIS) are:

Advantages:
• It occupies very less space (1/10th) compared to ordinary substations. Hence these Gas Insulated Substations (GIS) are most preferred where area for substation is small (eg: Cities)
• Most reliable compared to Air Insulated Substations, number of outages due to the fault is less
• Maintenance Freeb
• Can be assembled at the shop and modules can be commissioned in the plant easily


Disadvantages:
• Cost is higher compared to Ordinary Conventional Substations
• Care should be taken that no dust particles enter into the live compartments which results in flash overs
• When fault occurs internally,diagnosis of the fault and rectifying this takes very long time (outage time is high)
• SF6 gas pressure must be monitored in each compartment, reduction in the pressure of the SF6 gas in any module results in flash overs and faults


Reply
seminar flower
Super Moderator
******

Posts: 10,120
Joined: Apr 2012
#15
24-09-2012, 01:18 PM

Gas-Insulated Switchgear for Substations


.pdf   Gas-Insulated.pdf (Size: 1.09 MB / Downloads: 130)

Introduction

Common characteristic features of
switchgear installation


Because of its small size and outstanding
compatibility with the environment, SF6 -
insulated switchgear (GIS) is gaining constantly
on other types. Siemens has been
a leader in this sector from the very start.
The concept of SF6 - insulated metal-enclosed
high-voltage switchgear has proved
itself in more than 70,000 bay operating
years in over 6,000 installations in all parts
of the world. It offers the following outstanding
advantages.

Protection of the environment

The necessity to protect the environment
often makes it difficult to erect outdoor
switchgear of conventional design, whereas
buildings containing compact SF6-insulated
switchgear can almost always be
designed so that they blend well with the
surroundings.
SF6-insulated metal-enclosed switchgear
is, due to the modular system, very flexible
and can meet all requirements of configuration
given by network design and operating
conditions.

Protection against pollution

Its metal enclosure fully protects the
switchgear interior against environmental
effects such as salt deposits in coastal
regions, industrial vapors and precipitates,
as well as sandstorms. The compact
switchgear can be installed in buildings
of uncomplicated design in order to minimize
the cost of cleaning and inspection
and to make necessary repairs independent
of weather conditions.

Free choice of installation site

The small site area required for SF6-insulated
switchgear saves expensive grading
and foundation work, e.g. in permafrost
zones. Other advantages are the short
erection times and the fact that switchgear
installed indoors can be serviced regardless
of the climate or the weather.

SF6-insulated switchgear
up to 145 kV, type 8DN8


Three-phase enclosures are used for type
8DN8 switchgear in order to achieve extremely
low component dimensions. The
low bay weight ensures minimal floorloading
and eliminates the need for complex
foundations. Its compact dimensions and
low weight enable it to be installed almost
anywhere. This means that capital costs can
be reduced by using smaller buildings, or
by making use of existing ones, for instance
when medium voltage switchgear
is replaced by 145 kV GIS.
The bay ist based on a circuit-breaker
mounted on a supporting frame (Fig. 41).
A special multifunctional cross-coupling
module combines the functions of the disconnector
and earthing switch in a threeposition
switching device. It can be used as
 an active busbar with integrated disconnector
and work-in-progress earthing
switch (Fig. 41/Pos. 3 and 4),
 outgoing feeder module with integrated
disconnector and work-in-progress earthing
switch (Fig. 41/Pos. 5),
 busbar sectionalizer with busbar earthing.
For cable termination, a cable termination
module can be equipped with either conventional
sealing ends or the latest plug-in
connectors (Fig. 41/Pos. 9). Flexible singlepole
modules are used to connect overhead
lines and transformers by using a splitting
module which links the 3-phase encapsulated
switchgear to the single pole connections.
Thanks to the compact design, up to three
completely assembled and works-tested
bays can be shipped as one transport unit.
Fast erection and commissioning on site
ensure the highest possible quality.
The feeder control and protection can be
located in a bay-integrated local control
cubicle, mounted in the front of each bay
(Fig. 42). It goes without saying that we
supply our gas-insulated switchgear with all
types of currently available bay control systems
– ranging from contactor circuit controls
to digital processor bus-capable bay
control systems, for example the modern
SICAM HV system based on serial bus
communication.
Reply

Important Note..!

If you are not satisfied with above reply ,..Please

ASK HERE

So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page

Quick Reply
Message
Type your reply to this message here.


Image Verification
Please enter the text contained within the image into the text box below it. This process is used to prevent automated spam bots.
Image Verification
(case insensitive)

Possibly Related Threads...
Thread Author Replies Views Last Post
  GAS INSULATED TRANSFORMER seminar class 6 5,286 26-06-2015, 07:03 PM
Last Post: Guest
  gas insulated substation seminar report jaseelati 0 327 18-12-2014, 03:09 PM
Last Post: jaseelati
  electrical engineering seminar or presentation topics with full report list computer science crazy 11 29,424 12-04-2014, 10:08 PM
Last Post: Guest
  harnessing high altitude wind power full report computer science topics 5 18,815 27-09-2013, 09:32 AM
Last Post: seminar projects maker
  On Single-Electron Technology Full Adders Report seminar projects maker 0 634 26-09-2013, 01:10 PM
Last Post: seminar projects maker
  Development of the Next Generation of Insulated Gate Bipolar Transistors pdf seminar projects maker 0 431 20-09-2013, 04:06 PM
Last Post: seminar projects maker
  circuit breaker full report project topics 12 20,583 20-09-2013, 12:52 PM
Last Post: Guest
  POWER LINE CARRIER COMMUNICATION full report seminar ideas 2 2,325 07-09-2013, 09:20 AM
Last Post: study tips
  full subtractor study tips 0 347 14-08-2013, 04:35 PM
Last Post: study tips
  FULL ADDER study tips 0 293 14-08-2013, 04:34 PM
Last Post: study tips