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CHAPTER:- 1
INTRODUCTION
Everybody must be having a thought that a thermal power plant is a place where electricity is produced.
But do you know how it is produced? The chemical energy stored is converted to heat energy which
forms the input of power plant and electrical energy produced by the generator is the output. Power is
the single most important necessity for the common people and industrial development of a nation. In a
convectional power plant the energy is first converted to a mechanical work and then is converted to
electrical energy. Thus the energy conversions involved are:
The first energy conversion takes in what is called a Boiler or Steam Generator, the second in what is
called a Turbine and the last conversion takes place in the Generator.
A thermal power station is a power plant in which the prime mover is steam driven. Water is heated,
turns into steam and spins a steam turbine which drives an electrical generator after it passes through the
turbine, the steam is condensed in a condenser and recycled to where it was heated; this is known as a
Rankine cycle.
Commercial electric utility power stations are usually constructed on a large scale and designed for
continuous operation. Electric power plants typically use three-phase electrical generators to produce
alternating current (ac) electric power at a frequency of 50Hz.

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Fig 1.1:- Kalisindh Thermal Power Plant, Jhalawar
The site of Kalisindh Thermal Power Project is located in Nimoda, Undal, Motipura, Singhania and
Devri villages of Tehsil Jhalarapatan, Distt. Jhalawar. The proposed capacity of coal based
Thermal Power Project is 1200 MW. The project site is about 12 km from Jhalawar (Distt. Head
quarter ) and NH-12 .It is 2km from state highway No.19 and 8 km from proposed Ramganj Mandi -
Bhopal broad gauge rail line.
The site selection committee of Central Electricity Authority has visited the Nimodha and its
adjoining villages of Jhalawar Distt. And site was found techno-economical feasible for setting up
of a Power Project. The Govt. of Raj. have included that project in 11 th five year plan. The
estimated revised cost of the project is Rs.7723 Crores. M/s. TCE Banglore has been appointed
as the technical consultant for the project. The state irrigation department has allotted 1200 mcft
water for the project from proposed Kalisindh Dam. The origin of the Kalisindh river is from northern
slop of Vindya Mountains . The river enters from MP to Rajasthan near village Binda. After flowing
145 km in Rajasthan, the Kalisindh river merges in Chambal river near Nanera village of Distt.
Kota.Its catchment area is about 7944 sq.km in Jhalawar & Kota Distt. The existing Dam is
located at Bhawarasa village, primarily for P.H.E.D. purpose is being uplifted for providing a

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storase of 1200mcft water for this power project. The GOR has allotted 842 bigha Government
land and aquired 1388 bigha private khatedari land for the thermal project .Phase-1 will be
constructed on 1400 bigha land only.
EPC contract has been awarded to M/s. BGR Energy System Chennai on dt.09/07/08, through
ICB route at cost Rs.4900 Crores. Ministry of coal, Govt. of India has allotted ‘Paras east and Kanta
basin coal blocks to RVUN in Chhattisgarh state.
The RVUN has formed new company under joined venture with M/s. Adani Enterprises for mining
of coal blocks and new company started the work. Annual coal requirement for the project is 56
LacsTPA. GOR also decided to setup two new units of 2x660 MW in next few years.

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PRINCIPLE OF OPERATION
For each process in a vapour power cycle, it is possible to assume a hypothetical or ideal process
which represents the basis intended operation and do not produce any extraneous effect like heat
loss.
1. For steam boiler, this would be a reversible constant pressure heating process of water to
form steam.
2. For turbine, the ideal process would be a reversible adiabatic expansion of steam.
3. For condenser, it would be a reversible a constant pressure heat rejection as the steam
condenser till it becomes saturated liquid.
4. For pump, the ideal process would be the reversible adiabatic compression of liquid
ending at the initial pressure. When all the above four cycles are combined, the cycle
achieved is called RANKINE CYCLE. Hence the working of a thermal power plant is
based upon Rankine cycle with some modification.

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Fig. 2 :- THERMAL PLANT PROCESS DIAGRAM
A PULVERIZED COAL FUELED POWER PLANT
A typical pulverized coal fueled power plant is based on Rankine Thermodynamic cycle.
“A Rankine cycle is a vapour cycle Furnace that relies on the isentropic expansion of high pressure
gas to produce work”. Let us see a superheat Rankine cycle:

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Fig. :- RANKING CYCLE
Where, Wt – mechanical power produced by turbine.This facility first produces steam in a boiler
(steam generator). This steam is used to rotate turbine which is connected to a shaft of generator.
Hence electricity is produced here. The used steam is then condensed in a condenser, and the
condensed liquid is used again in the steam generator. This is a simple phenomenon, understood by
everybody. For all this we need a fuel. As the name suggest here coal is used as fuel. Coal is one of
the cheapest and most preferred fossil fuel used as a key to most of the power plants. Usually
delivered by train from Mines to the Coal Handing Plant (CHP). The CHP unloads this it
become more economical to unload the coal. Then the coal stacked, reclaimed, crushed, and
conveyed it to the storage silos near the steam generator. Then it is fed through the Feeder to the
Pulverizer. Feeder is mainly used to weight the amount of coal going to the Pulverizer per hour. From
the Feeder the coal is fed to the Pulverizer which powders it and then it is carried to the steam
generator using pressurized air. Within the steam generator the coal is atomized and burned and the
heat energy produced is used for producing steam. Here two types of steam namely superheated &
reheated steam are produced in a cycle. The steam turbine generator converts the thermal energy of
superheated and reheated steam to electrical energy.

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Fig. :- ENERGY CYCLE
Initially the superheated steam is fed to High Pressure (HP) turbine. It has a temperature of 540° C
(approx.) and a pressure of about 140 Kg/cm2. Then the exhausted steam from it is taken to the
reheater so that it can be reheated and fed back to Intermediate Pressure (IP) turbine. Here the
temperature is maintained the same as that of superheated steam but pressure is reduced to 35
Kg/cm2. Then the exhausted steam is directly fed to Low Pressure (LP) turbine having the reduced
temperature and pressure of about 1 Kg/cm2. Then the exhausted steam from the LP section is
condensed in the condenser. The condensed liquid is moved from condenser by Condensate Pumps
through Low Pressure Regenerative Feedwater heaters to a Deaerator. Boiler Feed Pumps (BFPs)
moves the deaerated liquid through HP heaters to the steam generators. Extraction steam is supplied to
the LP & HP regenerative heaters to improve cycle efficiency. Then comes to the system of fans
which keeps the system working by providing the valuable air where required. There are three pairs
of fans, namely, Forced Draft (FD) fan, Induced Draft (ID) fan, Primary Air (PA) fan. FD fans
supplies combustion air to the steam generator and PA fans transports the coal into the steam
generator. ID fans remove the flue gases from the steam generator and exhaust it through chimney.
Cooling water for the condenser is supplied by the circulating water system, which takes the
heat removed from the condenser and rejects it to the cooling towers or other heat sink.
This all working is controlled from a single place called control room. It enables the operator to
direct the plant operation for reliable and efficient production of electrical energy. This is achieved by
the control system installed by the C & I group. These are DAS (Data Acquisition System), ACS
(Analog Control System), FSSS (Furnace Safeguard Supervisory System), and other relays governing
numerous activities. Last but not the least is the switching and transmission methods used here. The
generated power cannot be transmitted as such. It is stepped up to 132 KVA or 400 KVA then passed
through a series of three switches an isolator, a circuit breaker and an isolator. Three phase system
is used for the power transmission. Each generator has its own switchyard and transmission
arrangement.

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THERMAL PLANT OPERATION PROCEDURE
The basic understanding of the modern thermal power station in terms of major systems involved can
be done under three basic heads viz. generating steam from coal, conversion of thermal energy to
mechanical power and generation & load dispatch of electric power.
1. COAL TO STEAM:
The coal is burnt at the rate up to 200 tonnes per hour. From coal stores, the fuel is carried on conveyor
belts to bunkers through coal tipper. It then falls into coal pulverizing mill, where it is grounded into
powder as fine as flour.
Air is drawn in to the boiler house by drought fan and passed through Preheaters. Some air is passed
directly to bunker and rest, through primary air fan, to pulverizing mill where it is mixed with
powdered coal. The mixture is then carried to bunker of furnace where it mixes with rest of the air and
burns to great heat. This heats circulating water and produces steam, which passes to steam drum at
very high pressure. The steam is then heated further in the Superheater and fed to high pressure
cylinder of steam turbine. The steam is then passed to other cylinders of turbine through reheater. The
spent steam is sent to condenser, where it turns back to water called condensate. Condensate is sent to
lower part of steam drum through feed heater and economizer. The flue gases leaving boiler are used for
heating purpose in feed heater, economizer, and air Preheater. The flue gases are then passed to electro-
static precipitator and then, through draught fan, to chimney.
2.STEAM TO MECHANICAL POWER:
Steam first enters the high pressure cylinder of turbine where it passes over a ring of
stationary/fixed blades which acts as nozzle and directs steam onto a ring of moving blades.
Steam passes to the other cylinders through reheater and the process is repeated again and again.
This rotates the turbine shaft up to 3000 rpm.
At each stage, steam expands, pressure decreases and velocity increases.

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3.MECHANICAL TO ELECTRICAL POWER:
The shaft is connected to an alternator’s armature.
Thus, the armature is rotated and electric current is produced in the stator’s windings. The
generated electricity is of order 25,000 volts.
4.SWITCHING AND TRANSMISSION:
Electricity generated can not be transmitted as such. It is fed to one side of generator’s transformer and
stepped up to 132000, 220000, or 400000 volts. It is then passed to a series of three switches a isolator,
a circuit-breaker, and another isolator. From circuit-breaker, current is taken to bus bars and then to
another circuit-breaker with it’s associated isolator before being fed to the main Grid. Each generator
has its own switching and transmission arrangement. Three-phase system is used for power
transmission.
5. CONTROL AND INSTRUMENTATION:
Control and Instrumentation (C & I) systems are provided to enable the power station to be operated
in a safe and efficient manner while responding to the demands of the national grid system.
These demands have to be met without violating the safety or operational constraints of the plants.
For example, metallurgical limitations are important as they set limits on the maximum permissible
boiler metal temperature and the chemical constituents of the Feed water. The control and
Instrumentation system provides the means of the manual and automatic control of plant operating
conditions to: Maintain an adequate margin from the safety and operational constraints. Monitor these
margins and the plant conditions and provide immediate indications and permanent records. Draw the
attention of the operator by an alarm system to any unacceptable reduction in the margins. Shut down
the plant if the operating constraints are violated.
TYPES OF INSTRUMENTS

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The different types of instruments normally used are given below:
INDICATORS :– These are of two categories, namely local and remote. Local indicators are self-
contained and self-operative and are mounted on the site. The Remote indicators are used for
telemeter purposes and mounted in the centralized control room or control panel. The indicators
are sometimes provided with signalling contacts where ever required. The remote indicators
depend on electricity, electronics, pneumatic or hydraulic system for their operation and
accordingly they are named. The indicator can be classified as analogue or digital is based on
final display of the reading.
RECORDERS : – These are necessary wherever the operating history is required for
analysing the trends and for any future case studies or efficiency purposes. Recorders can be of
single point measuring a single parameter or multipoint measuring a number of parameters
by single instruments. Multipoint recorders are again categorized as multipoint
continuous or multipoint dot recorders. The multipoint dot recorders select the point one after
the other in a sequence wherea s the continuous recorders measure simultaneously all the
Points.
Chapter:-02
COAL HANDLING SYSTEM

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Fig.:- WAGON TIPLAR, FIG-08 CRUSHUR HOUSE, PROCESS VIEW
Coal Supply in KATPP:- Ministry of coal, Govt. of India has allotted ‘Paras east and Kanta
basin ‘coal blocks to RVUN in Chhattisgarh state. The RVUN has formed new company under
joined venture with M/s. Adani Enterprises for mining of coal blocks and new company started the
work. Annual coal requirement for the project is 56 Lacs.
MILLS
These are basically coal pulverizing mills. Thermal power stations use pulverized coal firing
system. In this the coal is reduced to fineness such that 70 to 80% passes through 200 mesh sieves.
This fine powdered coal is called pulverized coal and is carried forward to the burner by air through
pipes.
Advantage of pulverized coal firing system: –
1. Efficient utilization of low grade
2. Flexibility in firing.
3. Ability to meet fluctuating load.
4. Better reaction to automatic control
5. High efficiency of boiler.
6. Easy complete combustion.
 The only disadvantage being its high initial cost.
2.2 STAGES OF COAL HANDLING PLANT :-
WAGON TIPPLER:-
The term Wagon Tippler contains two words WAGON & TIPPLER. Wagon means the

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compartment of train which is just like a container which is used to carry the coal from mines to
generating stations & the word Tippler means a machine, which is used to unload the wagon into the
hopper. Hopper is just like a vessel which is made of concrete & it is covered with a thick iron net
on its top. Here big size coal pieces are hammered by the labours to dispose it into the hopper. Coal is
fed into mill through Gravimetric feeder. When the A.C. supply is switched on the bowl rotates and
due to centrifugal force, the coal moves in the outward direction. As the coal come between grinder
and bowl; it gets pulverized. The unwanted material is removed through scrapers. The pulverized coal
is then carried to burners by primary air through outlet openings. The heavier particles, as they
rise, collide with classifiers and
fall back in mill for further grind. Sealing air is provided through seal air fan to avoid deposition
of coal dust in bearings and spring mechanism.
CONVEY OF COAL TO CRUSHER HOUSE:-
After unloaded the coal wagon into the concrete hopper, the supply of coal is control by Apron
Feeder and Scrapper. Apron feeder is made of iron. After passing through the scrapper conveyor
the coal is fed into the Roll Crusher where the crushing of coal takes place. In the roll crusher there
are two shafts on which metal hammer are mounted, these two rollers rotate in opposite direction
to each other. When the coal comes in between these two rollers it gets crushed into small pieces
and then convey to the separator through belt conveyor. In Pent house there is a belt weightier which
is used to weight the belt which carry the coal and feed into the separator with the help of Flap Gate.
PRIMARY CRUSHER HOUSE:-
Coal crusher house is a part of coal handling plant where the coal is crushed with the help
of a crusher machines .In crusher machine there is pair of two shafts on which hammer are
fixed. Both shafts rotates in opposite direction due to which when coal comes between the two
shafts crushed into the small pieces and conveyed to the bunkers or open storage (stacker)
according to the requirement through the belt conveyor.
STACKER & RECLAIMER :-
Stacker is a place where the open storage of a coal takes place. Reclaimer means the unloading of coal
from the stacker.
COAL MILL :- In coal mill, coal is pulverized or crushed properly into the powdered form. Hot air

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is mixed with powdered coal to remove the moisture from the coal, which increases the efficiency of
plant. Pulverization is done to increase the surface area of coal. From coal mill coal is drift to the
furnace with the help of air.
There are four main equipment of coal mill, which are as follows:-
Bunkers :- These are basically used to store crushed coil which comes from crusher house.
Feeders :- These are used to control the supply of crushed coal to the mill depending upon load
condition.
Feeder pipe :- Feeder pipe are used to convey the crushed coal to the Tube mill or Bowl mill.

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Chapter :-3
RAW-WATER CYCLE & COOLING SYSTEM
3.1 WATER TREATMENT PLANT
The principal problem in high pressure boiler is to control corrosion and steam quality. Internal
corrosion cost power station crores of rupees. The water available can not be used in boilers as such.
The objective of water treatment plant is to produce the boiler feed water so that there shall be
 No scale formation · No corrosion
 No priming or forming problems
The treated water is called ‘Dematerialized Water’. The treatment process can be divided in two
sections:
1. Pre-treatment section
2. Demineralisation section
PRE-TREATMENT SECTION
Pre-treatment plant removes suspended solids like clay, salt, plants, micro-organisms etc form raw
water to give clarified water. Suspended solids can be separable or non-separable. Separable
solids are heavier & large and can easily be removed by an aerator. Non-separable solids have
finer size and take long to settle down. Hence they are required to be flocculated. In this, water is first
dozed with lime and alum. This forces finer particles to coagulate increasing their weight and size.
Non-separable solids can now be separated in Clar flocculator. The clarified water is then stored
in clarified water storage tanks.

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WATER TREATMENT STAGE: -
River (raw water) → Clarification → Filtration → Demineralization
CLARIFICATION AND FILTERATION OF WATER:-
River water contains different impurities i.e.,
 Suspended impurities.
 Biological impurities
 Soluble impurities
Colloidal impurities
WORKING :- The raw water enters through valve and then chemicals is added. Chlorine and
alum are added. Chlorine is added to remove bacteria etc. Alums are added to make the impurities
heavier, once the impurities become heavier than a no. of flocs are formed. By mixing the alums,
heavy impurities are settle down due to gravity and later removed. The time required for the
formation of floc is called retention time, which is generally 3 hours, but this can’t be achieved as it
requires large tank. In order to cope up the limitation
CLARRIFOCCULI TANK is used. This flocculation tank is consisting of
1. Clarification zone
2. flocculation zone
After the addition of chemical the basic requirement arises is of mixing. Thus flash mixers are
used. Normally the chemicals mix naturally but when the raw water contains much impurity than
agitators are used to mix them. Clarrifocculation tank has a central pillar which has four windows at
90 degrees. The outer circle is half of windows so that level of water is arise then it flows down
through these windows into overflow channel. After mixing from flash mixer, the water passes on to

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central pillar and follows the path as shown in fig. i.e., it moves to max. floc area and comes out
from window at 3.5 m height. The downward flow is through perforated wall which sinks the raw
water. Due to the long path a retention time of 4 hour is easily available.
Fig.:- CLORIFICATION SYSTEM,
Fig.:- WATER FLOW CYC
The capacity of water in this plant is 1000*1000 lt./hr. In flocculation zone max. floc is formed
and after removing it, the clear water moves into clarifier. Some impurities are weightless and do
not settle down so they are passed through filter beds. There are two types of filter beds.
1.Gravity filter bed.
2.Forced filter bed.
In FORCED FILTER BEDS raisins are added to settle down the impurities. In GRAVITY
FILTER BEDS graded gravels are arranged. At bottom gravels of big size are there and above
other gravels are arranged according to size. Above it grit and most of the above is sand.
The clarified water enters into sump. Sump is fully closed leaving one window to see the level.
Since it is fully closed hence no foreign matter can enter into it.
3.2 DEMINERALIZING PLANT
Water is mainly used for cooling purpose of different parts like bearing winding etc. in KaTPP. For this
water should be Demineralized (D.M. water).
In this plant process water is freed from all dissolved salts. Equipments for demineralization
plant is supplied and erected by GE INDUSTRIAL (India) Ltd. .This plant consists of two streams,
each stream with activated carbon filter, weak acid, carbon exchanger and mixed bed exchanger.
The filter water goes to DM water plant through 250 dia header from where a header top off has
been taken off to softening plant. Two filtered water booster pumps are provided on filtered water
line for meeting the pressure requirement in DM plant.
When pressure drop across filter exceeds a prescribed limit from the activated carbon filter enter
works acid carbon unit. The dilation water enter the weak base anion exchanger unit water then enters
degasified unit where free CO2 is scrubbed out of water by upward counter flow of low pressure air

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flow through degassifier lower and degassed water is pumped to strong base exchanger (anion –
exchanger).
Arrangement for designing ammonia solution into dematerialized water after mixed bed unit
has been provided for pH correction before water is taken into the condensate transfer
pump the DM water to unit condenser as make up. The softening plant is a plant designed to
produce 100 cubic m/hr. of softened water per stream. It is using for bearing cooling.
PH VALUE OF WATER: -
This is recommended to feed the water in the boiler at 25 degree centigrade and pH
value is 8.2 to 9.2 up to 28 days and the pressure is 59 Kg cm2.
3.3 COOLING TOWER
It is used to reject heat into the atmosphere. There are two types of the cooling tower.
(1) Natural draft
(2) Forced draft
Natural draft tower used vary large concrete chimney to introduce air through the media. They are
generally used for water flow rate about 45000 m3 /hour. It is used in utility power station. Here hight
of cooling tower is 202M.
Forced draft tower utilize large fans to force or suck air through circulating water. The water
falls downward over fills surface which helps in increase the contact time between the water and air.
This held maximize heat transfer between two media. Cooling rates depend upon fan diameter and
speed. This type of tower much wider used.
Here 2 NDCT used each of two units and hight of cooling tower is 202 meter.water tubes are used
inside of cooling tower for cooling purpose.
This structure is constructed in r.c.c. shell poud floor and its derified water channel c.w. For bay.
The entire structure is supported combined circular rafting constructed in different segments
with slanted colomn fotting to support 17 m hight circular sectional reckar colmns. This r.c.c. shell

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of 150 m dia. And 205 m height . It is made of m 50 grade r.c.c. Which was also done at sight. There
will be 200 colomns poud floors that will generate cascading effect for cooling
Foundations:-
The design and construction of cooling tower foundations shell be in accordance with the requirments
continuous foundations shell be provided for cooling tower more then 75 m height. The foundation is
design for loadis indicated in as follows:-
A.) Thermally induced local loading
B.) Cold water basin floor loading
C.) Surface charge load of 15 KN per 50m
The basin floor at each compartment should be sloped towards a collecting sump for effectively
drainage the water to permit desilting. To minimize the obstruction in flow of water only the
columns supporting the fill structure shell be projected above the basin floors.
BEARING COOLING WATER
Water from river comes in plant heat exchanger, where its temperature cools
down and that goes in AHP to make slurry. There are 480 plates’ exchangers. BCW requirements
of boiler and turbine auxiliaries of both the units is meet from BCW soft water overhead tank
with the capacity of 2000 cubic meter.

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FIG-10 COOLING TOWER
DEAERATOR: -
DEAREATION OF FEED WATER: -
In deareation dissolve gases such as oxygen & CO2 are expelled by preheating the feed
water before it enters the boiler. All-natural water contains dissolve gases in solution (i.e.
oxygen + CO2) are released when water heated.
CONDENSER: -
In condenser steam changes into water. The basic requirement is to remove latent heat
from the steam which is removed by another water (clarified water) when it accepts the latent
heat and becomes hot, than it is passed to cooling tower. In cooling tower, the water is cooled
and then mix with river water.

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PUMPS: -The entire green coloured instrument is pumps which are 18 in no. to further pass the water.
1. FILTER WATER TRANSFER PUMP: -
It is soft section consisting of two types:-BEARING COOLING WATER PUMP: -All the bearing
temperature is controlled through oil bath and filter water is used. Oil is used to cool the
supplied water. Here doesn’t used raw water because at the time of puncture it enters in the
machinery part and small impurity may stop the operation.
CONDENSATE WATER PUMP:-This pump is coupled with blue coloured motor. In order to couple
it with motor a little opening is left through which water leaks out when pumped
2.FILTER WATER TRANSFER PUMP: -This pump transfers water to D.M. plant. These
pumps are in D.M. section.
3.POTABLE WATER PUMP: -These pump pumps clear water for potable purpose
for whole plant.

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3.4 H2 GENERATING PLANT
Hydrogen gas is used for cooling purpose for rotor of the generator. For cooling purpose we
must use 99.9% pure hydrogen. To avoid fire so we have to apply Hydrogen cooling. It is very
difficult to generate and store the Hydrogen gas because it is very explosive. Hydrogen as a coolant
has the following advantages over air:
1. More efficiency and less noise.
2. Better Cooling.
3. More life and less maintenance.
4. Less chance of fire hazard.
5. Better rating.
GENERATING PLANT:-
Hydrogen gas is produced by electrolytic dialysis by mixing KOH in D.M. water. This reaction is done
in electrolyser where Anode and Cathode are applied. Anode plate is used for collecting H2 and
Cathode plate is used for collecting O2. For electrolytic dialysis 3000 Ampere current is passed into
electrolyser. O2 is released to atmosphere and H2 is sent to next machinery for further treatment.
COLLECTING PROCESS: -
H2 Gas from electrolyser → Refrigerator for cooling → Separator to separate the moisture →
Compressor → Catalytic purifier → Dryer (Al2O3) → H2 cylinder. In compressor H2 is treating in
three steps where pressure is raised up to 130 Kg/cm2. In dryer Alumina is used to absorb moisture.
CAPACITY: -
In KaTPP the full day capacity of H2 generating is Not calculated because plant is in on construction.
Its approx. 40 cylinders per day. But in plant per day utilization are of 15 cylinders. Per cylinder
capacity is 200-250 kg and stored H2 is 99.8% pure.

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CHAPTER-04
STG SYSTEM
4.1 BOILER
Boiler can simply defined as the device where any liquid is boiled or Boiler may be defined as a
device that is used to transfer heat energy being produced by burning of fuel to liquid, generally
water, contended in it to cause its vaporization. Boiler, in simple terms, can be called “Steam
Generator”. The following are factors essential for the efficient combustion usually referred as “The
three T’s”.

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A) TIME – It will take a definite time to heat the fuel to its ignition temperature and having
ignited, it will also take time to burn.
B) TEMPERATURE – A fuel will not burn until it reaches its ignition temperature.
C) TURBULENCE – Turbulence is introduced to achieve a rapid relative motion between the
air and fuel particles.
CLASSIFICATION:
Boilers may be classified under different heads on different basis: -
1. Depending upon “Use”
1.1. Stationary (land) boilers
1.2. Mobile boilers
1.2.1. Marine boilers
1.2.2. Locomotive boilers
2. Depending upon “Tube contents”
2.1. Fire tube boilers
2.2. Water tube boilers
3. Depending upon “Tube shape”
3.1. Straight tube boilers
3.2. Bent tube boilers.
3.3. Sinuous tube boilers
4. Depending upon “Tube position”
4.1. Horizontal or Vertic

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4.2. Inclined
5. Depending upon “Furnace position”
5.1. Externally fired.
5.2. Internally fired.
6. Depending upon “Heat source”
6.1. Solid, liquid or gas
6.2. Waste of chemical process
6.3. Electrical energy
6.4. Nuclear energy
7. Depending upon “Circulation”
7.1. Natural circulation
7.2. Positive or forced circulation.
A boiler is an enclosed that provides a means for combustion heat to be transfer into
water until it becomes heated water or steam. Its volume increases 1600 times. The process
of heating a liquid until reaches its gaseous states its called evaporation. The boiler
system comprises of
feed water system steam system Fuel system
1. Feed Water system: -
It provides water to the boiler and regulate feed according to demand.
1. Steam system: -
It collects and controls the steam produced in the boiler steam are directed through a
piping system to a point of use. Steam pressure is regulated using valves and checked with
pressure gauges.
2. Fuel system: -
Fuel system includes all equipment used to provide fuel to generate the necessary heat for
higher boiler efficiency feed water is preheated by economizer using the waste heat in the flue
gases.

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WATER TUBE TYPE BOILER USED IN KaTPP WITH 97M HIGHT Various motors use in
boiler are different rating and parameters 32KW ,15KW,11KW,&3.3KW
Parameter in 15KW motor.

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FIG-11 FLOW OF WATER & STEAM, FIG-12 KaTPP BOILE
BOILER AUXILIARIES:-
Efficiency of a system is of most concerned. Thus, it is very important to maintain a

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system as efficient as possible. Boiler auxiliaries help in improving boiler’s efficiency.
Following are the important auxiliaries used.
ECONOMIZER: Its purpose is to preheat feed water before it is introduced into boiler
drum by recovering heat from flue gases leaving the furnace.
SUPER HEATER: It increases the temperature of steam to super-heated region.
REHEATER: It is used for heat addition and increase the temperature of steam coming
from high pressure turbine to 540o.
SOOT BLOWER: It blows off the ash deposited on the water wall surface. It uses steam.
for blowing purpose.
AIR PREHEATER: It pre-heats the air entering the furnace by recovering heat from
flue gases in order to ease the combustion process.
DRAFT FANS: They handle the supply of air and the pressure of furnace.
OIL GUNS: They are used to spray oil to raise the temperature of furnace to ignition
temperature of fuel.
WIND BOX: It distributes the excess air uniformly throughout furnace.
BOILER MOUNTINGS
These are used for the safe operation of boiler. Some examples of mountings used are
water level indicator in drum, furnace temperature probe, reheat release valve, pressure
gauges indicating steam pressure etc.

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4.2 TURBINE
Turbine is an m/c in which a shaft is rotated steadily by the impact of reaction of steam of working
substance upon blades of a wheel. It converts the potential energy or heat energy of the working
substance into mechanical energy. When working substance is steam it is called ‘Steam Turbine’.
In the steam turbine the pressure of the steam is utilized to overcome external resistance and the
dynamic action of the steam is negligibly small.
Principle:- Working of the steam turbine depends wholly upon the dynamic action of steam. the
steam is caused to fall with pressure in a passage of nozzle, due to this fall in pressure, a whole
amount of heat energy is converted into mechanical energy & steam is set moving with the
reactor velocity. The rapidly moving particle of steam enter the moving part of turbine and here
suffers a change in the direction of motion which gives rise to change of momentum and therefore
to a force. This constitutes a driving force to a machine.
The passage of the m/c through the moving part of the turbine commonly called the blade, may take
place in such a manner that the pressure at the outlet sides of the blade is equal to that of the inlet
side. Such a turbine is broadly termed as outlet turbine or
Impulse type:-
On the other hand, the pressure of the steam at outlet from the moving blade may be less than
that at type inlet side of the blade. The drop of pressure suffered by the steam during its flow through
the moving blades causes a further generation of kinetic energy within the blades and adds to the
propelling force, which is applied to the turbine rotor, such a turbine is broadly termed as Reaction
Turbine. Here in kalisindh thermal N600-16.7/587/537, Re-Het, Three Casing Four Exhaust,
Tandem Compound Condenser Type Turbine Used.

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34. 34

35. 35

36. 36
4.3 GENERATOR
FIG-4.3.1 GENERATOR DIAGRAM
Generator is the main part of thermal power station or any power plant. A generator is a machine
which converts mechanical energy into electrical energy.
The generator has gas cooling construction enclosing the stator winding, core and hydrogen
coolers. The cooling medium hydrogen is contained within the frame and circulation by fans
mounted on either ends of the rotor .The generator is driven by directly coupled steam turbine at
a speed of 3000 rpm.
Provision has been made for circulating the cooling water in order to maintain a constant
temperature of the coolant i.e., H2 as measured at the fan section side which is in touch with the

37. 37
temperature of the winding, core and other parts as per load.
Each of the 2 units have been provided with 3-phase turbo generator rated output 706MVA,
18.525KA, 22KV, 0.85 lagging p.f., 984 rpm and 50 cycles/sec. The generator has closed.
loop of hydrogen gas system for cooling of the stator and rotor at a pressure of 4.5kg/sq.-cm(g).
is filled in a gas tight outer casing of the generator. H2 gas circulates inside the casing by two.
single stage rotor mounted fans on either side of the rotor. The heated H2 is in turn cooled by
six surface type water coolers axially mounted inside the generator casing.
The cooling water is supplied to H2 coolers from the BCW overhead tank Each generator has
terminal led out of its casing and a star point is formed by sorting the neutral side terminals by a
sorting bar. The neutral is grounded by a 1-phase 11000/220V, Neutral grounding transformer,
whose secondary coil is laminated by laminated strip with mechanical ventilating holes, is
connected across a 650V, class 0.4- o h m , 50 kW neutral grounding resistors and relays for
protection of generator against stator earth faults and stator in turn faults (rating 1 amp).
The H2 gas inside the generator casing is prevented from leaking in between the rotor and
shields, by a continuous oil film maintained between the rotor and sealing rings. The shaft sealing
system have two independent oil sources associated pumps, regulators, coolers filters, electrical
controls and alarm system. Two independent oil sources are provided for air side and H2 side
sealing rings. The oil circuit of the H2 side of the shaft seal is closed and the oil is vacuum treated. In
KaTPP QFSN-600-2-22F type turbine used

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FIG-4.3.2 STEAM OVERVIEW
Chapter:- 5
TRANSFORMER & SWITCHYARD SYSTEM

39. 39
5.1 TRANSFORMER
Transformer is made up of following parts: -
1. Core
2. Winding
3. On load tap changer
4. Tank
5. Bushing
6. Auxiliary equipment
7. Insulating Oil
8. Cooling system
In KaTPP there are various transformers for various purposes. They are:-
1.Generating Transformer (GT)
2.Unit Transformer (UT)
3.Unit Auxiliary Transformer (UAT)
4. Interconnecting Transformer (ICT)
5. Unit Service Transformer
6.Station Transformer
UNIT TRANSFORMER: -
Unit Transformer are installed to fed supply to HT switchgear. There
are two 80MVA Transformer installed near GT which are fed throw main busducts coming from
generator and fed to the HT switchgear. After step down THIS SUPPLY UP TO 11 KV HT
switchgear used to supply on the major auxiliary of the plant like BFP, CWP, ID,FD,PA
fens etc. The unit transformer is used to HT switchgear, and it supply voltage 22/11KV to UAT
and different motors in boiler. UT is rated for 48/64/80MVA,22/11.6/11.6KV, Dyn11yn11 type
winding. This permit to voltagedown up to 11KV.it have 2 radiator.

40. 40

41. 41
UNIT AUXILLIARY TRANSFORMER: -
There is one more Transformer known as Station Transformer used only for initializing.
the start-up of the station (Main Plant). It is very beneficial during emergency situations such as
tripping of Units, shutdown etc.
In KaTPP 2 UAT used for step down voltage 11/3.3KV supply used to switchgear
equipment’s
INSTRUMENT TRANSFORMER: -
Instrument transformers have wide range in application such as measurement of voltage,
current, power & energy power factor, frequency. It is also used for protection circuit of the power
system for operation of over current, under voltage, earth fault and other type of relays, The

42. 42
instrument transformer can be classified as
(A). CURRENT TRANSFORMER: -Current transformer is used for monitoring the current for the
purpose of measuring and protection. The dead tank current transformer accommodates the
secondary cores inside the tank which is at ground potential. CT used current ratio 1000:1 and
range is 1A-5A.
(B). POTENTIAL TRANSFORMER: -The function of P.T. is to step down the voltage so that
it can be measured by standard measurement. Output in pt is 110V.The transformer is generally core
type and form Y-Y group and having the insulation as oil and papers.

43. 43
CHAPTER-06
ESP & ASP SYSTEM
6.1 ELECTROSTATIC PRECIPITATOR
If suspended particles are not removed from the flue glass, and it is allowed to be released in
environment, then it would cause a serious threat to the environment, so it becomes necessary to
extract suspended particles from the flue glass and for this purpose ESP is widely used.
Precipitation of ash has another advantage too. It protects the wear and erosion of ID fan. To achieve
the above objectives, Electrostatic Precipitator (ESP) is used. As they are efficient in precipitating
particle form submicron to large size they are preferred to mechanical precipitation.
WORKING PRINCIPLE: -An electrostatic precipitator is defined as a device which
utilizes electrical forces to separate suspended particles. The electrostatic precipitator consists of two
sets of electrodes, one in form of thin wire called “discharge or emitting electrode” and other
set is called “collecting electrode” in their form of plate ESP POWER SUPPLY
COMPONENT .

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CONSTRUCTION: -
The main parts of ESP are as follows: -
 Casing
 Hoppers
 Collecting system 
 Emitting system
 Rapping mechanism for collecting system 
 Rapping mechanism for emitting system
 Insulator housing
CASING: -
It is designed for horizontal gas flow to provide for heat expansion, the casing is
supported by roller bearing support.
HOPPERS: -They are of pyramidal shape. Angle between hopper corner and Hz is never less than 55
degrees.
COLLECTOR SYSTEM: -
The profiled collecting electrode is based on the concept of dimensioned electrode stability.
The upper plates have hooks and lower edge has a receiving plate. EMITTING SYSTEM: -
The framework is thoroughly braced and forms a rigid box like structure, the emitted
electrode is made of hard stainless-steel wires.
RAPPING MECHANISM FOR COLLECTING SYSTEM: -
The system employs fumbling hammer which are mounted on an Hz. Shaft in a
staggered fashion. A uniform rapping effect is provided for all collecting plates in one row

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.Rapping frequency is very low to minimize the dust loss. The hammers are operated by
motor, so that they strike the plate at fixed frequency.

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6.2 ASH HANDLING PLANT (A.H.P)
The ash produced on the combustion of coal is collected by ESP. This ash is now
required to be disposed off. This purpose of ash disposal is solved by Ash Handling Plant (AHP). There
are basically 2 types of ash handling processes undertaken by AHP:
· Dry ash system
· Ash slurry system
DRY ASH SYSTEM
Dry ash is required in cement factories as it can be directly added to cement. Hence the dry ash
collected in the ESP hopper is directly disposed to silos using pressure pumps. The dry ash from
these silos is transported to the required destination.
ASH SLURRY SYSTEM
Ash from boiler is transported to ash dump areas by means of sluicing type hydraulic system which
consists of two types of systems:
Bottom ash system Ash water system
BOTTOM ASH SYSTEM
In this system, the ash slag discharged from the furnace is collected in water impounded scraper
installed below bottom ash hopper. The ash collected is transported to clinkers by chain conveyors. The
clinker grinders churn ash which is then mixed with water to form slurry.
ASH WATER SYSTEM-
In this system, the ash collected in ESP hopper is passed to flushing system. Here low-pressure
water is applied through nozzle directing tangentially to the section of pipe to create turbulence and
proper mixing of ash with water to form slurry. Slurry formed in above processes is transported to
ash slurry sump. Here extra water is added to slurry if required and then is pumped to the dump area.

47. 47
FLY ASH SYSTEM
Even though ESP is very efficient, there is still some ash, about 0.2%, left in flue gases. It is disposed to
the atmosphere along with flue gases through chimney.

48. 48
.

49. 49
FIG-18 ASH HANDLING SYSTEM
CHAPTER-07
SWITCHYARD, C & I SYSTEM
7.1 SWITCH YARD
Switchyard is considered as the HEART of the Power Plant. Power generated can be worthful
only if it is successfully transmitted and received by its consumers. Switchyard plays a very
important role as a buffer between the generation and transmission. It is a junction, which carries the
generated power to its destination (i.e., consumers). Switchyard is basically a yard or an open area
where many kinds of equipments are located (isolator, circuit breaker etc…), responsible for
connecting & disconnecting the transmission line as per requirement (e.g., any fault condition).
Power transmission is done at a higher voltage. (Higher transmission voltage reduces
transmission losses).
Both units are 22KV in KaTPP. stepped-up to 400KV by the Generating transformer & then
transmitted to switchyard. Switchyards can be of 400KV, & 200KVIn SSTPS there are two

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interconnected switchyards: -
(i) 400KV SWITCHYARD (ii) 220KV SWITCHYARD
The 400KV & 220KV switch yard have conventional two buses arrangement with a bus coupled
breaker. Both the generator transformer and line feeder taking off from switch yard can be taken to
any of the two buses, similarly two station transformers can be fed from any two buses. Each of these
line feeders has been provided with bypass isolators connected across line isolators and breaker
isolators to facilitate the maintenance of line breaker. Each 400KV & 220KV lines have provision of
local break up protection.
In event of breaker which corresponding to bus bar differential protection scheme and trips out all the
breakers and connected zone bus bars differential protection scheme for bus I & II. All the breaker of
the connected zone and bus coupler, breaker will trip in event of fault in that zone. Here in KaTPP 4
outgoing line are as below: -
1.400KV TO BTAWDA
2.400KV TO BTAWDA
3.220KV TO JHALAWAR
4.220KV TO JHALAWAR
Each of the two bus bars has one P.T. one for each phase connected to it. Potential Transformer are
make in CROMPTON LTD. Each time line feeders has two nos. Core for each phase capacitor
voltage Transformer. for metering and protection are multicored single phase, oil filled,
nitrogen sealed and are provided at rate of one per phase.
-

51. 51

52. 52
FIG-19 SWITCHYARD
400KV SWITCHYARD:
There are on total 21 bays in this switchyard.
(A bay is basically a way for the incoming power from generator as well as outgoing power for
distribution).
3 for unit Generating Transformer.
2 for various distribution lines such as: BTAWDA LINE
2 for Bus coupler. 2 for TBC.
2 for ICT.
1 for the Bus Section.
There are on total 2 buses in 400KV switchyard. Bus-1
Bus-2
There are two transfer buses: Transfer bus-1.
Transfer bus 2
Transfer buses are kept spare and remain idle and are used only for emergency purposes. BUS
COUPLER-1 interconnects Bus-1 & Bus-2, respectively. Bus couplers are very beneficial as they
help in load sharing between the different buses.
TBC (TRANSFER BUS COUPLER):

53. 53
TBC is a bus coupler, which uses transfer bus when there is any defect in the equipments used (circuit
breakers & isolators) in any of the bay. Thus, it offers a closed path through transfer bus for the flow of
power in the respective bus.
A described of electrical equipment at 400KV & 220KV system are as follows: -
Circuit Breaker (VCB& SF6)
Isolators
Current Transformers (C.T.)
Potential Transformers (P.T.)
Lighting Arresters

Earthing Arresters
Capacitor Voltage Transformers (C.V.T.)

Interconnected transformer (ICT)
CIRCUIT BREAKER: -

54. 54
FIG-20 CIRCUIT BREAKER
It is an automatic controlling switch used in powerhouse, substation & workshop as well
as in power transmission during any unwanted condition (any fault condition-earth fault, over-current,
flashover, single phasing,). During such condition it cuts down the supply automatically by
electromagnetic action or thermal action. It can be used in off-load as well as on-load condition.
When a circuit breaker is operated by sending an impulse through relay, C.B. contact is made or
broken accordingly. During this making and breaking, an arc is produced which has to be quenched;
this is done by air, oil, SF6 gas etc….
Depending on the medium being used C.B.s can be categorized into various types. PLANT for
400 KV/220 KV switchyard only 4 main types are being used:-
ABCB (Air operated circuit breaker):- operated as well as arc quenched through air. Air
operated SF6 circuit breaker:- operated through air but arc quenching done through
SF6 gas.
MOCB (Minimum oil circuit breaker):-operated through spring action but arc
quenching done through oil (Aerosol fluid oil).
Hydraulic operated SF6 circuit breaker:- operated through hydraulic oil and arc

55. 55
quenching done through SF6 gas. Hydraulic operated SF6 circuit breaker is the most
efficient due to following reasons:-
1. Less maintenance.
2. Arc quenching capability of SF6 gas is more effective than air.
3. Heat transfer capacity is better in this C.B.
Here we use SF6 provided for each stage are SIEMENS made and rated for
420KV/245KV, 3150A Each pole has three interrupters which are oil filled with SF6 gas at
7.5 Kg/sq. cm.Here in KaTPP 3AP1FI/3AP2FI type CB are used for 400KV &220KV
Switchyard.
ISOLATERS:-
An isolator is also a switching device used to disconnect the line. As the
name suggests it isolate the line from the supply. It is always used in OFF-LOAD
condition. Whenever any fault occurs in the equipments present in the line, in order to
remove the fault or replace the device first of all supply is disconnected. But even after the
disconnection of the supply, the line remains in charged mode so before working on the
device (to remove fault) isolator should be made open.
Depending on the structure there are mainly two types of isolators:-
Pentagraph isolator.
Centre-break isolator (also known as Sequential isolator).
Pentagraph is generally used in buses whereas Centre-break (Sequential) is used in line.
Isolators may be operated in air (pneumatic), electrically or even manually.

56. 56
LIGHTENING ARRESTER:-
It is a protective device, which protects the costly equipments such as
overhead lines, poles or towers, transformer etc. against lightening. As the name suggests it arrests
the lightening of very high voltage (crores of KV) and dump it into the ground. It works on the
principle of easy path for the flow of current. L.A. is connected in parallel with the line with
its lower end connected and the upper end projected above the pole of tower.
LIGHTENING MOST:
It is present at the highest point, at the topmost tower of the switchyard and is connected
together by wires forming a web. The reason for its presence at the topmost point is to
grasp the lightening before it can come, fall and damage the costly equipments present in the
switchyard
EARTHING ISOLATORS:-

57. 57
The term ‘Earthing’ means connecting of the non-current carrying parts of the electrical
equipment or the neutral point of the supply system to the general mass of earth in such a
manner that all times an immediate discharge of electrical energy takes place without
danger. An Earthing isolator is a large value of capacitance. This can be charged up to
line voltage. Earthing isolator is used to discharge the line capacitance and work on it.
WAVE TRAPER:-
It is an equipment used to trap the high c arrier frequency of 500 KHz and above and
allow the flow of power frequency (50 Hz). High frequencies also get generated due to
capacitance to earth in long transmission lines. The basic principle of wave trap is that it has
low inductance (2 Henry) & negligible resistance, thus it offers high impedance
to carrier frequency whereas very low impedance to power frequency hence allowing it to
flow in the station.

58. 58
FIG-22 WAVE TRAPER
CURRENT TRANSFORMER:

59. 59
FIG-23 CURRENT TRANSFORMER
This Transformer is used for basically two major functions: -
Metering which means current measurement.
Protection such as over current protection, overload earth fault protection, Bus-bar
protection, Bus differential protection.
NOTE: - Secondary of the C.T should be kept shorted because (when secondary is kept
open) even the presence of a very small voltage in the primary of C.T will prove to be
harmful as it will start working as a step-up Transformer & will increase the voltage to
such a high value that primary would not be able to bear it & will get burned.
CT used current ratio 1000:1 and range is 1A-5A.CT connected in series while PT in
parallel.
PIPRI LINE:
In the case of emergency, e.g. total grid failure we take the power from Pipri line for the
initial starting of the station (Main Plant).

60. 60
CAPACITOR VOLTAGE TRANSFORMER(CVT)
FIG-24 CVT
This Transformer performs mainly two major functions: -
Used for voltage measurement. The high voltage of 400 KV is impossible to measure
directly. Hence a C.V.T is used, (connected in parallel with the line) which step-downs the
voltage of 400 KV to 110 KV, comparatively easy to measure.
The other most important function of C.V. T is that it blocks power frequency of 50Hz and
allows the flow of carrier frequency for communication. Each of the four line feeders
provided with three capacitor volt transformer for metering and synchronizing.
P.T (POTENTIAL TRANSFORMER):
This Transformer is connected in parallel with the line with one end earthed. It is only
used for voltage measurement by stepping-down the voltage to the required measurable
value.

61. 61

62. 62
7.2. SWITCHGEAR
The apparatus used for switching, controlling and protecting the electrical circuits and equipment is
known as switchgear.
A switch gear is one which makes or breaks electric circuit. Numerous problems arise in
erection, testing and commissioning of switch gear and various precautions are to be made in
operating and maintenance of switch gear.
Essential Features of Switch Gear: -
Complete Reliability
Absolutely certain discrimination Quick
operation
Provision for manual control provision for
instruments

63. 63
The main components of indoor switchgear are given below: -
I. Bus-Bars
ii.Isolating Switches
iii.Current Transformers
iv.Potential Transformers
v.Circuit Breaker
vi.Earthing arrangement
vii.Relays
viii.Inter-Locking arrangements
(i) BUS-BARS: -Bus bars are defined as the conductors to which several incoming and outgoing
lines are connected. They are essential component of Switchgear. They are made up of Cu. and Al. The
type and designers of Switchgear depends upon rated normal current and short circuit capacity. The Bus
bars are enclosed in bus bar chamber.
In KaTPP there are two types of indoor switch gear: 11 KV &3.3KV or High tension 3.415V or Low
tension.
(ii) ISOLATING SWITCHING: -
1.They are capable of-Interrupting the Transformer Magnetizing Current. Interrupting line
charging Current. Interrupting load Transformer Switching.
2.The main application is in connection with feed or bank Transformer feeders & their units
make it possible to switch out one Transformer while the other is still on load.
(iii) CIRCUIT BREAKER: -
They are capable of breaking the circuit on faults. It is heavy duty equipment mainly
utilized for protection of various circuit and separation of loads.
The Circuit Breaker uses on a relay or by manual signal. The Circuit Breakers which are
used in Switchgear are VCB type.

64. 64
(iv) EARTHED SWITCHES: -
Earthed switch is connected between line conductor and earth. Normally it is open when line is
disconnected. The Earthing switched is closed so as to discharge the voltage trapped online for
high voltage and so the capacitor between line and earth is charged to high voltage. For
maintenance work their voltage are discharged to earth by closing the earth switch.
(vi) INTER-LOCKING: -
The following type of inter- locking are provided.
The Circuit Breaker must be in open position before it is lowered in this position. The
Circuit Breaker can be closed only raising the final plug-in position.
The Circuit Breaker can be closed before raising plug in position.
Inter-locking between isolators, Earthing switches and Circuit Breakers are provided.
(vii) RELAYS: -A Protective Relay is a device that detects the fault and initiates the
operation of the circuit breaker to isolate the defective element from the rest of the
system.

65. 65
7.3 PROTECTION
The fault, which may occur in stator winding are-
1. Phase to phase fault.
2. Phase to ground fault.
3. Line to line fault.
4. Overheating.
These faults are due to-
1. Over voltage is because of system transients, lightening switching surges or sudden loss of
load.
2. Insulation deterioration due to any matter, moisture, corona discharge, Hardening of solid
and vibration.
It is very necessary to minimize the tripping time during any fault so that the lamination is not
damaged. The repairing being affected by replacing the faulty stator bar.A delayed clearance
may damage the lamination, so fire may be caused and partial re-insulation of core may be
necessary.
GENERATOR PROTECTION: -
The Generator is required to be tripped or isolated on following types of fault:
1. Failure of generating insulation.
2. Failure of prime mover turbine or boiler.
3. Failure of generating auxiliaries such as hydrogen gas system, seal oil system,
cooling system, and cooling water system.
4. Failure of grid.
The tripping command to the GT breaker is given by master trip relay 866, 86GT, and 86GB.
To make it feasible the master trip relay is connected to a common bus. All the protection
relays are connected in between the position of 220V.

66. 66
D.C. PROTECTION AND THE COMMON BUS: -
Protection devices are that detect abnormal condition in electrical circuit by measuring the
electrical quantity which are different under normal and fault condition. The basic electrical
quantities are voltage, current, phase angle and frequency.
(ii) ISOLATING SWITCHING: -
1. They are capable of-Interrupting the Transformer Magnetizing Current. Interrupting line
charging Current. Interrupting load Transformer Switching.
2. The main application is in connection with feed or bank Transformer feeders & their units
make it possible to switch out one Transformer while the other is still on load.
(iii) CIRCUIT BREAKER: -
They are capable of breaking the circuit on faults. It is heavy duty equipment mainly
utilized for protection of various circuit and separation of loads.
The Circuit Breaker uses on a relay or by manual signal. The Circuit Breakers which are
used in Switchgear are VCB type.
The relay doesn’t operate for normal voltage, normal current, normal phase angle and normal
frequency.
Different type of protection can be listed as:
1. Current operated protection.
2. Different protection.
3. Voltage operated protection.
4. Impedance type protection.
5. Frequency type protection.

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1. CURRENT OPERATED PROTECTION:-
a. Generator differential protection.
b. Generator negative sequence protection.
c. Generator output current protection.
d. Generator stator earth fault protection.
e. Generator REF protection.
f. Generator standby earth fault protection.
g. UAT o/c protection.
h. Generator o/c and short circuit protection.
i. L.B.B. protection.
2. DIFFERENTIAL PROTECTION: -
a. Generator overall differential protection.
b. UAT differential protection.
3. VOLTAGE OPERATED PROTECTION: -
a. Generator over voltage protection.
b. Generator stator E/F protection.
c. GT over voltage protection.
d. PT’s voltage supervision protection.
e. Generator inter-turn fault protection.
4. IMPEDANCE TYPE PROTECTION: -
a. Generator back up impedance protection. b. Generator loss
of exact protection. c. Generator pole slip protection.
5. FREQUENCY TYPE PROTECTION: -
a. Generator under protection Frequency.

68. 68
REQUIREMENT OF PROTECTIVE DEVICES:
Selectivity: Only that part of the installation containing fault should is disconnected. Safety
against faulty tripping: There should be no trip when there is no fault. Reliability: The device
must act within the required time.
Sensitivity: Lowest signal input value at which the device must act.
Tripping time: There should be a clear a distinction between the tripping time of the device,
considering the circumstances such as current and total tripping time for the fault.

69. 69
7.4 CONTROL ROOM
Various measurements can be taken at the control room simultaneously. The second important part of
the control room is relay part. Various relays are provided here BY AREVA LTD.

70. 70
Fig-26 CONTROL ROOM
CONTROL ROOM PANELS: -
FAN CONTROL DESK: -
ID Fan (Induced draft fan, 2nos.) at full load. FD Fan (Forced
draft fan, 2nos.) at full load. PA Fan (Primary air fan, 2 nos.)
at full load.
PRESSURE CONTROL DESK: -Furnace
pressure (5-10mmwcl.)
Primary air header pressure (750-800mmwcl).
1. FUEL CONTROL DESK: -
Coal oil flow.
Oil pressure.
Temperature of mill (inlet or outlet) Flow of air.
Drum level control, flow of steam water Pressure of
steam and water. Temperature of steam and water.

71. 71
7.5 AUXILIARY SUPPLY
Electrical supply system is the most important part of the thermal power station. The failure of
even comparatively small equipment could result in the losing of load or being put out of
commission.
SOURCE OF SUPPLY: -
1. URGENT AUXILLARY: -
Those are associated with running of units whose loss would cause an immediate reduction
unit output.
2. SERVICE AUXILLARY: -
These are common auxiliaries associated with one or more units. There loss would not affect
the output of the unit after considerable time of interval.
ELECTRICAL AUXILLARY SYSTEM: -
The KaTPP auxiliaries are operated at two voltages that are 6.6 KV and 415V. In respect of
6.6KV system, auto change over facility is provided for changeover of source of supply from unit
station in the case of unit trip out. The station is having the following auxiliary system:
More than 1500KW connected on 11KV.
More than 200KW less then 1500KW connected on 3.3KV. Less than 200KW on 415V. 220V D.C.
underground system for use in control and protection system.
3.3KV SYSTEM: -For the running unit, the unit auxiliaries are normally fed from generator itself
through 11/3.3 KV, 15 MVA unit auxiliary transformers, which is, connected to the unit switchgear viz.
USA and USB. Power to station auxiliaries and by unit auxiliary is fed from 220/3.3KV, 50 MVA
station transformers through two switchgear viz.

72. 72
415 V SYSTEMS: -For driving ten 100W motors and other accessories, we need 415V supply. For this
purpose, various transformer is used to step down 3.3 KV to 415V at various places. Oil circuit breaker
is provided between 3.3 KV bus and primary winding of transformer.
This system is three phase, 4-wire solidly grounded system is made available for 1000 KVA, 3.3 KV/
433V transformer.
240 V SYSTEMS: -240 V, 50 HZ. System is provided for control circuits of contactors modular of all
415 V switchgear or MCC space heating of various switchgears and space heating of all motor
above 37.5 KW rating. Each of modules with power contactor.
415 V /24 V SYSTEMS: -24 V, 50 HZ. Supply is used for winding heating of motors up to 37.5 KW.
This is made available by one or more 1- 415 V/24 V, 4 KVA transformers. Three transformers are
provided with 415 V switchgear/MCB.
400 KV SYSTEMS: -Two 400 KV buses have been provided in switchyard and are interconnected
through a bus coupler. Each of the 2X600 MW generators are connected to this system through a step
up 150/200/250MVA generator.
CHAPTER-08
EFFICIENCY & CONCLUSION
8.1. EFFICIENCY
In KaTPP we convert potential energy or chemical energy of the fuel into heat by the process of
combustion. The heat is given to the water, and it converts its form into steam. The pressure of steam
rotates the turbine, which is now in the form of kinetic energy. Generator producing electrical
energy, which is sand to different localities for utilization, consumes this kinetic energy.
Enthalpy is defined as the thermodynamic property of a system, is equal to the sum of its internal
energy and the product of its pressure and volume.
Enthalpy is an ancient Greek word meaning evolution and many eminent scholars have been
attempted to define it. It is a mathematical concept of available energy in the steam
Efficiency in the case of electrical generator process can be expressed as the amount of heat energy

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liberated in the boiler compared with the amount of electrical energy generated with it.
PLANT EFFICIENCY: -
We will divide whole plant efficiency in four-component efficiency:
(1). Cycle efficiency
(2). Turbo generator efficiency
(3). Boiler efficiency
(4). Auxiliary power efficiency
Overall = Boiler x Turbine x Cycle x Generator 

1. CYCLE EFFICIENCY: -
Cycle efficiency being the maximum possible heat energy that could be obtained from any set of
steam conditions employed. The operation of heat reduction of condenser, which is almost 50% of
the total available heat, makes.
ranking cycle
Cycle = energy available for conversion in
(a). Condenser vacuum.
(b). Steam conditions of CV &LV
(c). Regenerative feed heating.
2. ALTERNATOR EFFICIENCY: - The alternator is an efficient machine at about 98 % efficiency.
The losses are:
(a). Copper and iron loss
(b). Wind age losses
Operationally the plant is governed by the grid requirements. For voltage we use the set out from
generator transformer.
8.2 CONCLUSION
The first phase of Practical Training has proved to be quite fruitful. It provides an opportunity for

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encounter with such huge machines like wagon tippler, 600MW Turbines and Generators.
The architecture of the power plant, the way various units are linked and the way working of whole
plant is controlled make the student realize that engineering is not just learning the structure
description and working of various machine, but the great part is of planning proper management.
It also provides an opportunity to lean low technology used at proper place and time can cave a lot
of labour.
But there are few factors that require special mention. Training is not carried to its true spirit. It is
recommended that there should be some project specially meant for students where presence of
authority should be ensured. There should be strict monitoring of the performance of students and
system of grading be improved on basis of work done.
However, training has proved to be quite fruitful. It has allowed an opportunity to get an
exposure of the practical implementation to theoretical fundamentals.

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CHAPTER-09
REFRENCE
[1].www.rrvunl.com
[2].www.energyindia.com
[3].www.googleindia.com
[4].www.thermalpower.com
[5].www.scibe.com
[6]. Fundamentals of electrical engineering/power plant/tpp/655, Ashfaq Husain
Dhanpat Rai &Co.
[7]. Generation of electrical power/thermal station, B R Gupta, S. CHAND
PUBLICATION.
[8]. EPC Book Volume-V, TCE 5248.A-H-500001
[9]. Annual Report of TCE Ltd.

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[10]. Single Line Diagram GID-118-EL-XJ-2012, BGR REPORT ON KaTPP.
[11]. Single line diagram KaTPP Plan GID-2012, BGR ENERGY SYSTEM.
[12]. PPT On Thermal Plant/TCE/M Shreenivashan/104840/.
[13]. Assignment Shreenivashan /Tce /104840