Internship Report 2015
Internship Report Internship at
Kapko Power Plant, District
Muzzafarabad
From 22 July 2015 to 4 Sep 2015
____________________________________
By
Muhammad Saad Qureshi
National University of Sciences and Technology
(NUST), Islamabad
Internship Report 2015
Dedicated to my loving Parents
Without whom my world is empty
Internship Report 2015
Introduction:
An internship is an integral part of every engineering field as it
provides the students with an opportunity to gain practical knowledge pertinent to
their field. What they learn theoretically can actually be seen being implemented
practically. This not only aggrandizes their theoretical concepts, but also serves as
a means of amplifying their knowledge. For students of electrical engineering,
working in a power plant as an intern can be of immense use. They can see for
themselves the production of electricity which is the core item of their field.
Description of the Plant:
KAPCO is Pakistan's largest Independent Power Producer (IPP) with a nameplate
capacity of 1600 MW. KotAddu Power Plant (the "Power Plant") was built by the Pakistan
Water and Power Development Authority ("WAPDA") in five phases between 1985 and 1996 at
its present location in KotAddu, District Muzaffargarh, Punjab. In April 1996, KotAddu Power
Company Limited ("KAPCO") was incorporated as a public limited company under the
Companies Ordinance, 1984 with the objective of acquiring the Power Plant from WAPDA. The
principal activities of KAPCO include the ownership, operation and maintenance of the Power
Plant.
The Power Plant is a multi-fuel gas-turbine power plant with the capability of using 3
different fuels to generate electricity, namely: Natural Gas, Low Sulphur Furnace Oil and
High Speed Diesel to generate electricity. The Power Plant is also the only major plant in
Pakistan with the ability to self-start in case of a country wide blackout
On June 27, 1996, following international competitive bidding by the Privatization
Commission, Government of Pakistan (the "Privatization Commission"), the management of
KAPCO was transferred to National Power (now International Power) of the United Kingdom,
which acting through its subsidiary National Power KotAddu Limited (NPKAL), bought shares
representing a 26% stake in KAPCO. Later, NPKAL bought a further 10% shareholding in
KAPCO increasing its total shareholding to 36%.The other majority shareholder in KAPCO is
WAPDA with a present shareholding of 46%.
Following the successful completion of the offer for sale by the Privatization
Commission (on behalf of WAPDA) in February 2005, 20% of KAPCO’s shareholding is now
held by the General Public. On April 18, 2005 KAPCO was formally listed on all three Stock
Exchanges of Pakistan.
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The Power Plant is situated in District Muzaffargarh, Punjab, 90 K.M. North west of
Multan on the left bank of the River Indus at a distance of 16 K.M. From Taunsa Barrage. The
area is surrounded by agricultural land on the north and west side of KotAddu.
Vision Statement To be a leading power generation company, driven to exceed our shareholders'
expectations and meet our customer’s requirements.
Mission Statement
To be a responsible corporate citizen
To maximize shareholders' return
To provide reliable and economical power for our customer
To excel in all aspects relating to safety, quality and environment
To create a work environment which fosters pride, job satisfaction and equal
opportunity for career growth for the employees?
Plant General Characteristics
Gas Turbines 10
HRSGs 10
Steam Turbines 5
Installed Capacity 1600MW
Max. Load Generation 1541MW
Load According to IDC Test (1996) 1345MW
Load According to ADC Test (2010) 1355MW
No. of Feeders 6 x132KV; 6 x220KV
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Max. Generation in one day 35,667Mwh
KAPCO GAS TURBINE POWER STATION
KAPCO 1600MW
Block 1 Energy Block
3
SIEMENS GERMANY
GT 1
STG 9
GT 2
FIAT
ITALY
GT 3 GT 4
STG 10
Block 2 Energy Block 2
ALSTHOM FRANCE
GT 5,6
STG 11
GT 7,8
STG 12
Block 3 Energy Block 1
SIEMENS GERMANY
GT 13,14
STG 15
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Description Of All Blocks
There are total three blocks in KAPCO. And there details are given below.
Block-I:
Block I is outfitted with six turbines altogether. In which four are Gas Turbine (GT1, GT2, GT3
and GT4) and other two are Steam Turbines (STG 9, STG10). The entire framework is in light of
the consolidated cycle.
GT1 and GT2 are German made and are fabricated by Siemens Engineering Co. Ltd. They have
a general warm effectiveness 28% and having an appraised limit of 100MW. Evaluated velocity
is 3000rpm. GT3 and GT4 are Italian made and are produced by Fiat Engineering Co. Ltd. They
have a general warm effectiveness 28% and having an appraised limit of 100MW. Appraised rate
is 3000rpm.
Steam Turbines (STG 9, STG 10) are produced by ABB. As there is not any sort of compressor
which utilizes around 60% vitality of GT, so its productivity is expanded up to half.
BLOCK 2:-
In Block-II there is additionally the same development of machines, yet they are all made of
ALSTHOM. Their rating and effectiveness is same as that of the block I. Every one of these
machines are synchronized straightforwardly to the transport bar, i.e. at 220 KV to connect with
transport bar.
BLOCK 3:-
Block III is furnished with three turbines altogether. In which two are Gas Turbine (GT13,
GT14) and another is a Steam Turbine (STG 15). Gas Turbines GT13, GT14 and STG 15 are
German made and are produced by the Siemens building Co. Ltd. They have a general warm
proficiency 45% in consolidates cycle mode.
Operations and Maintenance (O&M):
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The O&M of the plant is divided into various sections such as:
Electrical
Mechanical
Instrumentation & Control (I&C)
Equipment & Storage
Brayton Cycle:
Brayton cycle is an idealized cycle that describes the working of a constant
pressure heat engine. Gas turbine engines and jet engine work on Brayton cycle. A Brayton-type
engine uses three components:
Compressor
A Mixing Chamber (Combustor)
An Expander (Expansion Turbine)
Ideal Brayton Cycle:
1. Isentropic process - ambient air is drawn into the compressor, where it is
pressurized.
2. Isobaric process - the compressed air, then runs through a combustion
chamber, where fuel is burned, heating that air—a constant-pressure
process, since the chamber is open to flow in and out.
3. Isentropic process - the heated, pressurized air, then gives up its energy,
expanding through a turbine (or series of turbines). Some of the work
extracted by the turbine is used to drive the compressor.
4. Isobaric process - heat rejection (in the atmosphere).
Actual Brayton Cycle:
1. Adiabatic process - compression.
2. Isobaric process - heat addition.
3. Adiabatic process - expansion.
4. Isobaric process - heat rejection.
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Brayton Cycle
Rankine Cycle:
Rankine Cycle is a model that is used to describe the working and performance of
steam engines. It describes the process by which steam operated heat engines commonly found
in thermal power plants generate power. The heat sources used are nuclear fission or combustion
of fossil fuels like coal, gas, furnace oil etc.
There are 4 processes in Rankine Cycle:-
Process 1-2: The working fluid is pumped from low to high pressure. As the fluid is a
liquid at this stage, the pump requires little input energy.
Process 2-3: The high pressure liquid enters a boiler where it is heated at constant pressure
by an external heat source to become a dry saturated vapor.
Process 3-4: The dry saturated vapor expands through a turbine, generating power. This
decreases the temperature and pressure of the vapor, and some condensation may occur.
Process 4-1: The wet vapor then enters a condenser where it is condensed at a constant
pressure to become a saturated liquid.
Efficiency Improvement:
The efficiency of a Brayton Engine can be improved by:
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Regeneration:
In this method the still warm post-turbine fluid is passed through heat
exchangers to pre-heat the fuel entering the combustion chambers. This decreases the fuel
consumption for the same operating conditions.
Co-generation:
In this system, the exhaust heat from the Brayton engine is used for
other useful means like hot water production, heating neighboring building etc.
Combined Cycle:
A gas turbine operates in Brayton Cycle whereas a steam turbine operates on
Rankine Cycle. The efficiency of a gas turbine is somewhere around 35%,but it can be increased
to 60% or so if Combined Cycle configuration is used. In a combined cycle, the exhaust gases
from the gas turbine are used in Heat Recovery Steam Generator (HRSG) to convert water to
steam in order to run a steam turbine. The steam, after running the turbine, is condensed to water
in a condenser and is supplied back to the HRSG. Cold water, used to condense the steam in the
condenser, circulates between the cooling towers and the condenser.
Schematic Diagram of a Combined Cycle Power Plant
Safety Policy:
Safety is the first priority of GE and great stress is laid on
observing safety rules. The Company tries its best to make the environment of the
plant safe and secure. For this purpose, safety signs and instructions are exhibited
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in various places. The workers are educated and trained to work safely. Even we,
the internees, had to pass through the procedure of safety induction after which we
were allowed to visit the plant. In the safety induction, we were educated about the
importance of Plant Protection Equipment (PPE). We were also briefed about how
to react in case of an emergency. The primary PPEs without which nobody was
permitted to enter the premises of the plant are:
Safety shoes
Helmet
Goggles
In addition to these, ear plugs are necessary for the people working in noisy areas.
Water Treatment Plant (WTP):
Demineralized water, also known as the Demin Water is used in
the plant operation for various purposes. Water is treated to remove the dissolved
salts which will otherwise affect the boiler and turbine in various ways. The
presence of salts also increases the boiling the boiling point of water. But the main
problem is that as the water changes to steam in the boiler, the left behind salts can
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badly damage the boiler and if they somehow reach the steam turbine, they can
cause serious damage to the blades of the turbine. Therefore, water needs to be
treated before it can be used to run the steam turbine. Demin water is not used in
HRSG but also has its utility in gas turbine for other purposes that will be
discussed later.
Steps of Treatment:
Raw water
Double media filter
Activated carbon
Reverse osmosis (RO)
Chemical treatment
Demin water
The Generator:
Synchronous generator is utilized to change over mechanical vitality into electrical vitality.
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Essential Working guideline:
As indicated by Faraday's law of electromagnetic incitement:
"On the off chance that there is a relative movement in the middle of a conductor and
attractive field, then an EMF will be incited into the conductor".
To make this relative development, it doesn't make a difference whether the magnet is pivoted
and the conductor is stationary or the conductor is moving and magnet is stationary.
The greatness of the affected EMF is straightforwardly relative to the No of conductors (N) and
the rate of progress of attractive flux crossing the conductors.
Emf = N (dΦ/dt)
Different Parts of Generator:
Generally a generator consists of following parts:
Stator
Rotor
Excitation system
Carbon brushes and Slip rings
Retaining rings
Bearing
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Rotor grounding system
Cooling system
Excitation system:
The excitation framework is to supply the immediate current to the rotor which permits the
generator to keep up a controlled voltage between its terminals when joined with the system. A
voltage controller drives the excitation framework. The excitation power for the generator is
supplied by an exciter with pivoting diodes that are fitted to the end of the principle generator
shaft.
Generator cooling system
The warmth misfortunes emerging in the generator inside are scattered to the optional coolant
(cooling water) through the air. Direct cooling of rotor uproots problem areas and differential
temperature between the neighboring parts. Circuitous cooling is utilized for stator winding. Air
and hydrogen are two cooling media for the generator cooling. In KAPCO all generators are air
cooled.The advantages of the air cooling system are: lower cost price,short inspection and easy
maintenance.
Cooling air is coursed in the generator by two hub stream fans on the rotor shaft. Chilled air is
drawn by fans from cooler and afterward separated into three sections:rotor section,stator and
last air gap section.
Generator Protection:
There are diverse sorts of deficiency can happen onto the generators so the security of these
flaws to the generators we utilized a few insurances. These are given underneath.
Negative phase sequence protection.
Rotor earth fault protection.
Loss of excitation.
Reverse power protection.
Differential protection.
Under frequency/over frequency relay.
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Stator over current protection.
Stator over voltage protection.
Transformer:-
The transformer is a gadget that exchanges electrical vitality starting with one circuit,then on to
the next by attractive coupling without obliging relative movement between its parts. It for the
most part contains two or more coupled windings, and, by and large, a center to focus attractive
flux. A rotating voltage connected to one winding makes a period,fluctuating attractive flux in
the center, which incites a voltage in alternate windings.
TRANSFORMER TYPES:
Transformers are built so that their qualities coordinate the application for which they are
planned. The distinctions in development may include the extent of the windings or the
relationship between the essential and auxiliary windings. Transformer sorts are additionally
designated by the capacity the transformer serves in a circuit, for example,
Distribution Transformer
Start-up Transformer
Auxiliary Transformer
Auto Transformer
Matching Transformer
Isolation Transformer
Instrument potential Transformer
Isolation transformer.
Instrument current Transformer
According to cooling media:
They are classified as,
Dry (Air-cooled):
These are used according to the environment temperature and heat dissipation. They are less
expensive and they require less maintenance. Its main disadvantage is that its output rating
decreases by 1amp with an increase of one ˚C temperature.
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Oil type:
These transformers have following types, having oil as a cooling medium
Unit Transformer:
Unit transformers are utilized as a part of a wide range of sorts and applications. Unit
transformers are utilized oil cooled. Here unit transformers are utilized for overwhelming
obligation. Obstruct 2 Unit transformers have the capacity to change over 11kv into 220kv.Unit
Transformers take the voltage from assistant transformers and after that pass it to the switchyard.
Obstruct 2 has Alsthom CGEE transformer made in Italy.
Start-up Transformer:
KAPCO has the capacity of self-begin. There are two start-up transformers.The start-up
transformer is utilized to venture down the voltage. Here in KAPCO they are utilized to venture
down 132KV to 11KV and stimulate 11KV transport bar. To begin with a transformer is joined
with unit 1 and 2 while the second transformer is associated with unit 3 and 4. All units of
KAPCO are interconnected start-up transformer of the unit 1and 2 can give supply to unit 5and
6 comparatively start-up transformer of unit 3 and 4 is joined with unit 7 and 8. Obstruct 3 units
can get supplies from units 5 to 8.
Auxiliary Transformer:
They are exceptionally used to make a supply of unit stable,they take 11kv from the unit and
transformer it to unit transformer and to 11kv transport bar. The yield voltage of the unit can unique in
relation to correct 11kv, which can be 10.8KV or something so these transformers are utilized to stable
this quality.
Auto Transformer:
The autotransformer is for the most part utilized as a part of low power applications where a variable
voltage is needed. The autotransformer is a unique sort of force transformer. It comprises of one and
only winding. By tapping or interfacing at specific focuses along the winding, distinctive voltages can be
acquired. Just switchyard of 132kv has four autotransformers, which has the capacity to change over
132kv into 220kv they likewise change over, 220kv into 132kv.They are similar to interconnection
somewhere around 132kv and 220kv.
Matching Transformer:
It is used for CT to make the voltage equal on both sides o f the transformer. They have a smaller
size.
Instrument Potential Transformer(PT):
The instrument potential transformer (PT) ventures down voltage of a circuit to a low esteem that can
be viably and securely utilized for the operation of instruments, for example, ammeters, voltmeters,
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Wattmeters, and transfers utilized for different defensive purposes. They are utilized for Measuring
,Control ,Protection.
Instrument Current Transformer (CT):
The instrument potential transformer (PT) endeavors down voltage of a circuit to a low regard
that can be feasible and safely used for the operation of instruments, for instance, ammeters,
voltmeters, Wattmeters, and exchanges used for distinctive protective purposes. They are used
for Measuring,Control,Protection.
Control Transformer:
Control transformers are generally used in electronic circuits that require constant voltage
or constant current with a low power or volt-amp rating. Various filtering devices, such
as capacitors, are used to minimize the variations in the output. This results in a more
constant voltage or current.
Distribution Transformer:
They are by and large utilized as a part of electrical force circulation and transmission systems.
This class of transformer has the most elevated force, or volt-ampere evaluations, and the
highest continuous voltage rating. The force rating is typically dictated by the sort of cooling
methods the transformer may utilize. Some usually utilized strategies for using so as to cool are
oil or some other warmth directing material. Ampere rating is expanded in a dissemination
transformer by expanding the span of the essential and optional windings; voltage appraisals
are expanded by increasing the voltage rating of the protection utilized as a part of making the
transformer.
Energy losses in Transformer:
A perfect transformer would have no vitality misfortunes, and would in this manner be 100% proficient.
Regardless of the transformer being amongst the most productive of electrical machines, with
exploratory models utilizing superconducting windings accomplishing efficiencies of 99.85% vitality is
dispersed in the windings, center, and encompassing structures.
Losses in the transformer arise from:
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Winding resistance, Hysteresis losses,Eddy currents,Mechanical losses
Transformer Protection:
Protection are essential for electric gadgets, which shield them from annihilating and make them
more sheltered to utilize. They additionally have significance for specialists wellbeing. Bigger
things have a larger number of insurances than littler things.
For security reason there are two primary Operations;
Alert, Tripping
Alert:
Alert demonstrates the discriminating circumstance of parts. Caution will ring when a gadget
achieves its discriminating quality. It additionally demonstrates evidence in CCR.
Tripping:
Tripping is the following stride of caution. At the point when the machine or gadget don't work
on its standard working,then after sensible time breaker makes the defective part disengage and
safe the transformer.
There are essentially two sorts of insurance for a transformer.
Electrical
Non Electrical
Nonelectrical Protections:
Warm Protection
Weight Protection
Level Protection
Warm Protection:
Warmth can be created because of flash,hot climate and high voltage in substantial obligation
transformer. Mercury is accustomed to ring alert and for stumbling. At the point when the
transformer is warmed, mercury is moved from Pocket and works protection.To safe the
transformer we have two most imperative operation alert and tripping.
Weight Protection:
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Weight Relief worth is for body security. If there should arise an occurrence of starting oil is
warmed up and can harm the group of transformer . The quality discharge the weight that is
fabricated inside the body.
Level Protection:
Oil level abatements with the increment of temperature. On lessening of oil Alarm will ring,
however oil level security has no stumbling choice. As oil has basic reason for cooling so it is
vital to keep up the oil level.
Buchholz Relay Protection:
It is used for protection of oil filled transformer having low level of oil. This relay is installed between the
transformer tank and conservator. The minor faults in the transformer tank below the oil level actuate a
Buchholz relay so as to give an alarm
Electrical Protections:
High Voltage Protection
Over-Fluxing Protection
Earth Fault Protection
Differential Protection
Restricted Earth Fault Protection
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THE BATTERY ROOMS
Reason:
The reason for the battery room is to give DC supply expected to the transfer action(mostly for
insurance purposes).
They are likewise wellspring of excitation if there should arise an occurrence of power outage crash have
crucial utilization as DC reinforcement supply.
BATTERY ROOMS:
A battery room is a room in a facility used to house batteries for backup or
uninterruptible power systems.
They are of the two sorts regarding yield voltage.
Output voltage of 48V
Output voltage of 220V.
They are of driving corrosive sort having sulfuric corrosive (H2SO4) as the
electrolyte.
Basic Principle of Battery:-
The basic principle of the battery properly, first, we should have some basic
concept of electrolytes and electron affinity. Actually, when two dissimilar metals
or metallic compounds are immersed in an electrolyte, there will be a potential
difference produced between these metals or metallic compounds.
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SWITCHYARD
The switchboard is a place to import/export electricity. KAPCO has two switched
of 132 KV and 220 KV.
Switchyard of 132 KV:
First feeder goes to INDUSTRIAL ESTATE MULTAN.
Second feeder goes to MUZAFFARGARH-1
Third feeder goes to GUJRAT SOUTH
Forth feeder goes to D.I.KHAN-1
Fifth feeder goes to D.I.KHAN-2
Sixth feeder goes to KOT ADDU
This switchyard has a single transmission plan. This plan is not exceptionally
powerful in a bad situation in light of the fact that it can totally dead the line and
we don't have standby way. It contains 2 transport bar of 132KV and BAYS from 4
to 22. From switchyard of 132 KV 6 transmission lines go to different parts of the
country. BAY 18 and 20 are joined with autotransformer which change over 132
KV into 220 KV.BAY 6 and 17 are associated with startup transformer they
change over 132KV into 11KV GT 1,2,3 and 4 are joined with BAY 4,5,16 and 19
individually. While ST-9 and ST-10 are associated with BAY 7 and 15 separately
Switchyard of 220KV:
It contains two bus bars and BAYS from 1 to 14. This yard has one and half plan
of breakers in which we have a standby way to proceed with our transmission with
no trouble. All out 12 feeders go out from the KAPCO six feeders are 220KV and
six are 132KVA.
The subtle element of six feeders of 220KV is given beneath.
From bay 1 feeder goes to MUZAFFAR GARH
From bay 2 feeders goes to AES PAKGEN
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From bay 6 feeders goes to VEHARI
From bay 7 feeders goes to NEW MULTAN 6
From bay 13 feeder go to NEWMULTAN 3
From bay 14 feeder go to NEWMULTAN 4
After stride up, the 220 KV yield from the generator transformer is encouraged to
both of the two bus bars through transfers and circuit breakers and these are
associated with different feeders through different equipment's.
Bus BARS: -
Bus bar is a term utilized for fundamental bar of conveyor conveying an electric
current to which numerous associations may be made. These are primarily a
helpful method for associating switches and other hardware's into different courses
of action.
Each switchyard have two bus bars. Most are made of aluminum and all the
approaching and active supplies are joined through the bus bars.
Important:-
Having three phase transmission, the phases are red, yellow and blue and if two of
three phases combine what happens? The answer is whole plant breakdown and
high spark will be produced because phase to phase and phase to neutral create
huge damage to plant.
CURRENT TRANSFORMERS: -
The main purpose of current transformer is to step down the current to a level that
the indicating and monitoring instruments can read. When rated current flows
through its primary winding, a current of nearly 1 amp will appear in its secondary
winding.The primary is so connected that the current being passes through it and
secondary winding is connected to an ammeter. The CT steps down the current to
the level of the ammeter. The ratio of current transformers is as follows
600/1,1200/1,2400/1 amperes.
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LIGHTENING ARRESTORS: -
These are equipment’s designed to protect insulators of power lines and
electrical installations from lightening surges by diverting the surge to earth and
instantly restoring the circuit insulation to its normal strength with respect to earth.
The question is why high voltage has always fallen on Lightening Arrestors the
reason is it has zero ohms resistance, So, according to the Ohms Law if value of
resistance is low then high voltage and current will pass. So, that’s why the high
voltage sparks fell on it.. Lightening Arrestors having counters as well to count
how many times spark fall on it.
POTENTIAL TRANSFORMER:-
These are utilized to step do the voltage to a level that the potential curls of
showing and observing instruments can read. These are likewise used to bolster the
potential curls of transfers. The essential winding is joined with the voltage being
measured and the optional twisting to a voltmeter. The PT ventures down the
voltage to the level of the voltmeter.The potential transformers are joined in
parallel and present toward the end of the switch yard.
POWER TRANSFORMER: -
These are utilized to venture up,down the voltage starting with one A.C voltage
then onto the next AC voltage level at the same recurrence. Unit transformer takes
supply from helper transformer and exchanges it to switchyard transport bar.
WAVE TRAP: -
Wave trap is utilized to keep high recurrence signals from entering different zones.
NPCC is associated with all force stations through phone line which put their sign
on line and isolated from wave trap.
Demonstrating AND METERING INSTRUMENTS: -
Ammeters, voltmeters, Wattmeters, KWH meters, KVAR meters are introduced in
sub-station to watch over the streams,streaming in the circuit and the voltages and
the force loads.
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ISOLATORS: -
One of the cardinal measures for guaranteeing the full well being in doing took a
shot at the hardware in electrical establishments is to separate dependably the unit
or the area on which the work is to be done from all other live parts of the
establishment. To make preparations for slip-ups, it is vital that contraption, which
makes a noticeable break in the circuit, for example, Isolators, ought to do this.
Isolators don't have circular segment control gadgets in this way can't be utilized to
intrude on streams at which the curve will be drawn over the contacts.
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EARTHING SWITCHES:-
Earthing switch is used to discharge the voltage on deadlines to earth. An
auxiliary switch to provide interlock always accomplishes it.The earthing line
switches are helpful to ground all the inductions produced by other bus bars.
CIRCUIT BREAKERS: -
Circuit breakers are mechanical devices designed to close an open contact or
electrical circuit under normal or abnormal conditions. CB is equipped with a strip
coil directly attached to relay or other means to operate in abnormal conditions
such as over power, etc. In here, two types of CB are used. SF6 gas is used to
eliminate the spark that is produced by making a break of circuit breakers. Which
has 6 bar pressure and air is used to operate the breaker which has a pressure of
19bar. In block-3 switchyard portion breaker are hydraulically operated and air is
used for cooling. The hydraulic normal pressure is about 335 bar while SF6 normal
pressure is 7.6 bar while alarm and tripping pressure is about 7.2 and 7.1 bars
respectively.
Open, Close indication in Air blast Circuit breakers is as follows:
Green Color=Open
Red Color=Close
While in hydraulic Circuit Breaker:
1 represents Close
0 represents Open
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Disc
The purpose for installation of the disc is to fulfill safe distance requirement
and also cover and isolate voltage as well. If one of three disc breaks the circuit
still complete and in running condition. And the safe distance achieved by
installing a number of discs between the metal bar and ground.
Safe distance for 220kV switch yard is =2. 4m.
Safe distance for 132kV switch yard is =1. 4m.
Breaker:
It is an on load device which is used for safety purpose. It makes the
different electric component separately in case of fault.
Trip Supervision:
To check the healthiness of breakers trip supervision is used which is in
parallel to the breaker and in case of failure of breaker it give command the other
one and operate related breakers.
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Black Start
Crisis Function:
KAPCO is the exceptionally important force station of Pakistan on the grounds
that it has the office of self-begin. In the event of complete darkness, it can run its
self for this there is a Black has begun where the diesel generator produces power
empowers the excitation transport bars of GTS.
Bus Bar:
Dark begin transport bar is stimulated my DC batteries of 220V and help the diesel
generator to begin working
Diesel Generator:
Basically, it is not utilized, but rather as a part of instance of complete power
outage, it has exceptionally helped led to put force station without hesitation. It
gives 11 KV and stimulate the regular transport bar.
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Neutral and Ground
Neutral:
A reference connection in a power distribution system.
Ground:
A connection to the earth or to a conductive object such as an equipment
chassis.There are two objectives to the intentional grounding of electrical
equipment:
• Keep potential voltage differentials between different parts of a system at a
minimum to reduce the shock hazard.
• Keep impedance of the ground path to a minimum. The lower the impedance, the
greater the current is in the event of a fault. The greater the current, the faster an
over current device will open
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