Electricity generation is the process of generating electric power from other sources of primary energy. Electricity is most often generated at a power station by electro-mechanical generators, primarily driven by heat engines fueled by chemical combustion or nuclear fission but also by other means such as the kinetic energy of flowing water and wind. In Indian subcontinent the abundance of coal lead to the establishment of thermal power stations and governing bodies namely WBPDCL, DVC, NTPC act as pioneers in the generation of electricity.

1. A
Training Project Report
On
Coal Fired Steam Power
Plants
Submitted on completion of Vocational Training (Winter Session 2015-16)
At
Kolaghat Thermal Power Station
SUBMITTED TO: SUBMITTED BY:
Training Cell Arnab Nandi
Kolaghat Thermal Power Station Electrical Engineering
Academy of Technology
Training Session: 28th
December 2015 to 18th
January 2016

2. Page | 1
STUDENT DECLARATION
I undersigned, Arnab Nandi declare that this project report entitled, “Coal Fired
Steam Power Plants ”, is the result of vocational training carried out during
December 2015 to January 2016 at Kolaghat Thermal Power Station (KTPS), an
operating unit of West Bengal Power Development Corporation Ltd. (WBPDCL)
This project has not been previously submitted to any other university / institutions
for any other examination and for any other purpose by any other person. I will not
use this project report in future to use as submission to any other university,
institutions or any publisher. I also promise not to allow / permit any other persons
to copy / publish any part /full material of this report in any form.
ARNAB NANDI

3. Page | 2
PREFACE
This project report has been prepared in fulfillment of Vocational Training carried
out after 5th
Semester of B.Tech course. The vocational training was conducted at
Kolaghat Thermal Power Station (KTPS) under West Bengal Power Development
Corporation Ltd. (WBPDCL) from 28.12.2015 to 18.01.2016 . The blend of
learning and knowledge acquired during our practical studies at the power station
is presented in this project report.
The rationale behind visiting the power plant and preparing this report is to study
the mechanical overview, electrical overview, various cycles and processes of
power generation and details of control and instrumentations required in thermal
power plants. We have carried out this training under well experienced and highly
qualified engineers from various departments of KTPS, WBPDCL.
I have tried my best to cover all the aspects of the power plant and their brief
detailing in this project report.

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TABLE OF CONTENTS PAGE NO.
Introduction 4
Mechanical Overview 6
Coal Handling System 8
Water Treatment Plant 10
Boiler and Accessories 12
Steam Turbine 16
Ash Handling Plant 17
Cooling Tower 18
Chimney 18
Electrical Overview 19
Electric Generator 20
Transformers 22
Switchyard 24
Power Evacuation System 26
Conclusion 27
Bibliography 28

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INTRODUCTION
Electricity generation is the process of generating electric power from other sources of primary
energy. Electricity is most often generated at a power station by electro-mechanical generators,
primarily driven by heat engines fueled by chemical combustion or nuclear fission but also by
other means such as the kinetic energy of flowing water and wind. Other energy sources include
solar photovoltaics and geothermal power and electrochemical batteries.
In Indian subcontinent the abundance of coal lead to the establishment of thermal power stations
and governing bodies namely WBPDCL, DVC, NTPC act as pioneers in the generation of
electricity.
West Bengal Power Development Corporation Ltd.
West Bengal Power Development Corporation Limited (WBPDCL)
is a company owned by the Government of West Bengal with the goal
to carry on interalia the business of electric power generation and sup-
ply in the state of West Bengal, India. The main thermal power plants
under WBPDCL are in Kolaghat, Bakreswar, Sagardighi, Santaldih
and Bandel. WBPDCL Formed in July, 1985 with only one generat-
ing unit at Kolaghat having turnover of Rs.64 Crore paced up further
to Rs.2728 Crores in 2007-08 with 20 units at Kolaghat, Bandel, Bakreswar, Santaldih and
Sagardighi.
Thermal Power Stations under WBPDCL
Sl. No Plant Location Capacity(MW)
1 Kolaghat Thermal Power Station Mecheda, Medinipur 1260(6x210)
2 Bandel Thermal Power Station Bandel, Hooghly 450(4x60, 1x210)
3 Bakreshwar Thermal Power Station Birbhum 1050(5x210)
4 Santaldih Thermal Power Station Purulia 500(2x500)
5 Sagardihi Thermal Power Station Murshidabad 600(2x300)

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Kolaghat Thermal Power Station
Kolaghat Thermal Power Station (KTPS) is a major thermal power station in West Bengal. It is
located at Mecheda, approx. 55 km from Kolkata in the Purba Medinipur district. The power
plant is operated by West Bengal Power Development Corporation Limited. The power plant has
six units of 210 MW each for a total capacity of 1260 MW. The units were commissioned in two
stages during the period of 1984 to 1995.
 Total number of Units : 6 (3 in Stage I and 3 in stage II) of 210 MW each
 Total Energy Generation: 1260 MW
 Source of Water: - River Rupnarayan
Unit Synchronisation C.O.D
1 13.08.1990 09.09.1990
2 16.12.1985 09.03.1986
3 24.06. 1984 12.10.1984
4 29.12.1993 01.04.1995
5 17.03.1991 14.05.1991
6 16.01.1993 01.01.1994

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MECHANICAL OVERVIEW
The idea that steam has potential energy that can be converted to kinetic energy was given by
famous scientist, Sir James Watt. This idea became the governing principle of many mechanical
processes and finally led to the success of Thermal Power Energy. Thermal power is the largest
source of power in India. There are different types of Thermal power plants based on
the fuel used to generate the steam such as coal, gas, and diesel. About 65% of electricity
consumed in India is generated by thermal power plants.
A in a condenser and recycled to
where it was heated; this is known as
Rankine Cycle.
The energy efficiency of a
conventional thermal power station,
considered salable energy produced
as a percent of the heating value of
the fuel consumed, is typica 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 condensedlly 33% to 48%.
As with all heat engines, their
efficiency is limited, and governed by
the laws of thermodynamics.
Figure 1: Modified Rankine Cycle

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Figure 2: Unit Overview of Coal Based Thermal Power Plant

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COAL HANDLING SYSTEM
Coal is the basic and the oldest raw material used on large scale throughout the world.
Throughout history, coal has been a useful resource. It is primarily burned for the production of
electricity and/or heat, and is also used for industrial purposes, such as refining metals. A fossil
fuel, coal forms when dead plant matter is converted into peat, which in turn is converted into
lignite, then sub-bituminous coal, after that bituminous, and lastly anthracite.
Components of a Coal Handling Plant are:
Stockpile:
Stockpiles provide surge capacity to various parts of the CHP. Coal is delivered with large
variations in production rate of tons per hour. A stockpile is used to allow the wash plant to be
fed coal at lower, constant rate. A simple stockpile is formed by machinery dumping coal into a
pile, either from dump trucks, pushed into heaps with bulldozers or from conveyor booms.
Stacker:
Travelling, luffing boom stackers that straddle a feed conveyor are commonly used to create coal
stockpiles.
Reclaimer:
High-capacity stockpiles are commonly reclaimed using bucket-wheel reclaimers. These can
achieve very high rates. Tunnel conveyors can be fed by a continuous slot hopper or bunker
beneath the stockpile to reclaim material. Front-end loaders and bulldozers can be used to push
the coal into feeders. Sometimes front-end loaders are the only means of reclaiming coal from
the stockpile.
Figure 3: Reclaimer pouring into Stockpile

10. Page | 9
Crusher House:
After hand picking foreign material, coal is transported to the Crush house by conveyor belts
where it is crushed to small pieces of about 20 mm diameter. The crushed coal is then
transported to the store yard. Coal is transported to bowl mills by coal feeders.
Vibrating Feeder:
The coal stored in a huge hub is collected on the belt through vibrations created by the vibrating
feeder.
Magnetic Separator:
These are used to separate ferrous impurities from coal.
Reclaim Hopper:
Reclaimation is a process of taking coal from the dead storage for preparation or further feeding
to reclaim hoppers. This is accomplished by belt conveyors.
The purpose of the Coal handling plant in a thermal power plant is to process raw coal & insure
against their regular supply of coal which is dependent on many players in the supply chain. Coal
requirement for the 6 units is approximately 1600T/day.
 The function of a CHP is to receive process, store, and feed the Coal bunkers consistently
over the entire life of the Power plant.
 Coal is received from mines in the form of lumps, the sizes varying from 100mm to
350mm, in two types of wagons through Rail; BOBR meaning Bottom Open Bottom
Rapid discharge & BOXN meaning Bogie Open High Sided Side discharge Wagon
 BOBR wagons are unloaded in Track Hoppers & BOXN Wagons are unloaded by
Wagon tipplers.
 Coal is then supplied to the Crusher house through Roller screens or Vibrating feeders to
sieve the coal before feeding to the crusher; 20% of the coal that is received is already
<20mm size so this is separated & only larger lumps are fed to the Crusher.
 The crusher breaks the lumps to sizes <20mm which is the input size to the Coal
Pulverisers.
 The crushed coal is fed to the conveyors in the crusher house through Belt feeders; Coal
is either directly fed to the coal bunkers or to the Stacker/Reclaimers for stocking when
the bunkers are full.
 In case of non-receipt of wagons the coal from the stockpile is reclaimed through the
Stacker/Reclaimers and fed to the coal Bunkers.

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WATER TRATMENT PLANT
Raw water supply:
Raw water received at the thermal power plant is passed through Water Treatment Plant to
separate suspended impurities and dissolved gases including organic substance and then through
De-mineralised Plant to separate soluble impurities.
Deaeration:
In this process, the raw water is sprayed over cascade aerator in which water flows downwards
over many steps in the form of thin waterfalls. Cascading increases surface area of water to
facilitate easy separation of dissolved undesirable gases (like hydrogen sulphide, ammonia,
volatile organic compound etc.) or to help in oxygenation of mainly ferrous ions in presence of
atmospheric oxygen to ferric ions. These ferric ions promote to some extent in coagulation
process.
Coagulation:
Coagulation takes place in clariflocculator. Coagulant destabilises suspended solids and
agglomerates them into heavier floc, which is separated out through sedimentation. Prime
chemicals used for coagulation are alum, poly-aluminium chloride (PAC).
Filtration:
Filters remove coarse suspended matter and remaining floc or sludge after coagulation and also
reduce the chlorine demand of the water. Filter beds are developed by placing gravel or coarse
anthracite and sand in layers. These filter beds are regenerated by backwashing and air blowing
through it.
Chlorination:
Neutral organic matter is very heterogeneous i.e. it contains many classes of high molecular
weight organic compounds. Humic substances constitute a major portion of the dissolved organic
carbon from surface waters. They are complex mixtures of organic compounds with relatively
unknown structures and chemical composition.
 Source of Water: River Rupnarayan (surface water)
Deep tube well (underground water)
 Raw water flow rate: 2700m3/hr(normal)
3400m3/hr(maximum)

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DM (Demineralised Water) Plant:
Demineralization is the process of removing mineral salts from water by using ion exchange
processes. Normal water is not used for the generation of steam as the dissolved salts would
corrode the metallic parts of the highly expensive equipments in direct contact with water.
 Pressure Sand filtration is frequently used and very robust method to remove suspended
solids from water. The filtration medium consists of a multiple layer of sand with a
variety in size and specific gravity.
 Activated carbon works via a process called adsorption, whereby pollutant molecules in
the fluid to be treated are trapped inside the pore structure of the carbon substrate. Active
charcoal carbon filters are most effective at removing chlorine, sediment, volatile organic
compounds (VOCs), taste and odor from water. They are not effective at
removing minerals, salts, and dissolved inorganic compounds.
 Cation Exchange Resin removes cations of bi-carbonate salts.
 Anion Exchange Resin will remove strong acids like HCl, H2SO4 which comes with the
water as free mineral acids.
 Degasifiers remove odors and hazardous gas materials such as hydrogen sulfide from
water treatment systems.
Figure 4: Layout of DM Plant

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BOILER AND ACCESSORIES
Boiler:
A boiler is a steam generator whose minimum capacity is 22.47 liters. Boilers are classified into
two types: fire tube boilers where flue gas
flows through tubes and feed water stored in
the shell is converted into steam, and water
tube boilers where feed water flows through
tubes and is converted into team. Water tube
boilers are used in thermal power plants due to
their high efficiency and high rate of steam
generation.
The pulverized coal is blown with part of the combustion air into the boiler plant through a series
of burner nozzles. Secondary and tertiary air may also be added.
Combustion takes place at temperatures from 1300-1700°C,
depending largely on coal-grade. Particle residence time in the
boiler is typically 2 to 5 seconds, and the particles must be small
enough for complete combustion to have taken place during this
time. This system has many advantages such as ability to fire
varying quality of coal, quick responses to changes in load, use of
high pre-heat air temperatures etc. One of the most popular systems
for firing pulverized coal is the tangential firing using four burners
corner to corner to create a fireball at the center of the furnace.
Figure 5: Schematic diagram of Water Tube Boiler
Figure 6: Tangential Firing

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Boiler Drum Internals:
The term “boiler drum internals” is generally taken to mean all the devices installed within the
boiler steam drum. This includes various types of steam separators, chemical feed lines, boiler
feedwater lines, and continuous blow off lines.
 The riser-downcomer circuit helps in natural circulation of water due to the difference in
densities.
 The baffle plates are used to direct
the steam to the steam separators.
 The cyclone steam separators
remove moisture from the steam.
This is accomplished by the steam
spinning or changing direction. The
water drains back into the steam
drum while the steam continues
upward through a screen and
scrubber that removes more
moisture.
Boiler Accessories:
Boiler accessories are those components which are installed outside the boiler to increase the
efficiency of the plant and to help in the proper working of the plant.
 Economizer is a device that transfers heat from flue gas to the feed water. If the water is
raised and thus there is a saving in the consumption of fuel.
 Superheater is used to increase the temperature of saturated steam entering the High
Pressure Turbine(HPT).
 The steam leaving the HPT is re-heated by Reheater and it enters Low Pressure Turbine.
 Air Preheater is used to transfer heat from flue gas to the air entering the furnace.
Figure 7: Arrangement of Boiler Internals inside Boiler Drum

15. Page | 14
 Technical Data of the Boiler:
 Make: ALSTOM India Ltd (Units 1 to 4)
Bharat Heavy Electricals Ltd. (Units 5 and 6)
 Drum Water Holding Capacity: 126.76 Tons (normal)
148.86 Tons (full)
 Technical Data of the Furnace:
 Type: Dry Bottom Furnace
 Volume: 3662 m3
 Mode of Firing: Front Firing(Units 1 to 4)
Tangential Firing (Units 5 and 6)
 Oil used in Firing: Light Diesel Oil
 Number of Burners: 24 (4rows X 6columns)
 Water Holding Capacity of Different Zones:
 Economizer: 16.9 Tons
 Superheater: 122.89 Tons
 Reheater: 102.94 Tons
 Induced Draft (ID) Fan:
Induced draft represents the system where air or products of combustion are driven out
after combustion at boiler furnace by maintaining them at a progressively increasing sub
atmospheric pressure.
 Number per Boiler: 2
 Type: Backward aerofoil blade, double inlet
 Gas Temperature: 143 °C
 Capacity: 9900m3
/min
 Forced Draft (FD) Fan:
The air for combustion is carried under forced draft conditions and the fan used for this
purpose is called Forced Draft (FD) fan.
 Type: Backward aerofoil blade, double inlet
 Number per Boiler: 2
 Gas Temperature: 27-48 °C
 Capacity: 7800m3
/min

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Figure 8: Cross Section through Boiler and Accessories

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STEAM TURBINE
A steam turbine is a prime mover which continuously converts the energy of high pressure, high
temperature steam supplied by the boiler into shaft work with low pressure, low temperature
steam exhausted to a condenser.
High Pressure Turbine (HPT) consists of 12 stages, first stage being bearing stage. The steam
flow through HPT being in reverse direction, the blades are designed for anticlockwise rotation.
After flowing through HPT the steam is reheated and enters Intermediate Pressure Turbine (IPT).
IPT has 11 stages. The rotors of HPT and IPT are connected by rigid coupling and have common
bearing. After flowing through IPT, steam enters the middle part of Low Pressure Turbine
(LPT). In LPT steam flows in opposite paths having four stages in each path. After flowing
through LPT the steam condenses in the condenser.
 Turbine Main Data:
 Rated Output: 210 MW
 Rated Speed: 3000 rpm
 Steam flow rate: 670 Tons/hr
 Rated Pressure of Steam at Inlet: 130kg/cm2
 Live Steam Temperature: 535°C
 Steam Temperature after Reheat: 535°C
Figure 9: Arrangement of Turbine Assembly
Figure 10: Rotor of Steam Turbine

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ASH HANDLING PLANT
A large quantity of ash is, produced in steam power plants using coal. Handling of ash is a
problem because ash coming out of the furnace is too hot, it is dusty and irritating to handle and
is accompanied by some poisonous gases.
The ash handling system handles the ash by bottom ash handling system, coarse ash handling
system, fly ash handling system, ash disposal system up to the ash disposal area and water
recovery system from ash pond and Bottom ash overflow. Description is as follows:
Bottom Ash Handling System:
Bottom ash resulting from the combustion of coal in the boiler shall fall into the overground,
refractory lined, water impounded, maintained level, double V-Section type/ Wtype steel-
fabricated bottom ash hopper having a hold up volume to store bottom ash and economizer ash
of maximum allowable condition with the rate specified. The slurry formed shall be transported
to slurry sump through pipes.
Air Preheater Ash Handling System:
Ash generated from APH hoppers shall be evacuated once in a shift by vacuum conveying
system connected with the ESP hopper vacuum conveying system.
Fly Ash Handling System:
Fly ash is considered to be
collected in ESP Hoppers. Fly
ashes from ESP hoppers, extracted
by Vacuum Pumps, fly up to
Intermediate Surge Hopper cum
Bag Filter for further Dry
Conveying to fly ash silo. Under
each surge hopper ash vessels
shall be connected with Oil free
screw compressor for conveying
the fly ash from Intermediate
Surge Hopper to silo.
Ash Slurry Disposal
System:
Bottom Ash slurry, Fly ash slurry and the Coarse Ash slurry shall be pumped from the common
ash slurry sump up to the dyke area which is located at a distance from Slurry pump house.
The following figure shows the operation of an ESP. the negatively charged fly ash particles are
driven towards the collecting plate and the positive ions travel to the negatively charged wire
electrodes. Collected particulate matter is removed from the collecting plates by a mechanical
hammer scrapping system.
Figure 11: Section through industrial Electrostatic Precipitator

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COOLING TOWER
Cooling towers cool the warm water discharged from the condenser and feed the cooled water
back to the condenser. Hot water outlet from the condenser is taken to the cooling towers. Water
enters the distribution header at the top of the
tower , flows into the distribution basin through
individual branch pipes to each cell provided
with valves. The water flows down through
distribution nozzle. The formation of droplets
increases the surface area, thus callusing release
of dissolved oxygen and the heat in the water.
 Make: Paharpur Cooling Towers Ltd.
 Type: Induced Draft, double cross flow
 Number: One for each unit
 Rate of flow: 29500m3/hr
CHIMNEY
A chimney may be considered as a cylindrical hollow tower made of bricks or steel. In KTPS the
chimneys of six units are made of bricks. Chimneys are used to release the exhaust gases
(coming from the furnace of the boiler) high up in the atmosphere. So, the height of the
chimneys are made high.
Figure 12: Heat disposal technique used in Cooling
Towers

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ELECTRICAL OVERVIEW
The electrical operation of a power plant comprises of generation, transmission and distribution
of electrical energy. In a power station both distribution and transmission operation can take
place. When power is sent from power station to all other power station in the grid, it is known
as distribution of power. When power plant is driving power from other power station it is
known as transmission of power/electrical energy.
Each unit of Stage I is connected to 220kV grid through 160MVA, 15.75kV transformer called
Generating Transformer(GT) and each unit of Stage II to 400kV grid through 250MVA,
15.75kV GT. For supply of auxiliary power to each unit, 2 Auxiliary Transformers are connected
to each generator. Interbus Transformer (IBT) works as a linear connector transformer between
220kV and 400kV grid. To supply auxiliary power during start up/ shut down, or in case of unit
auxiliary power failure, two reserve transformers (Station Auxiliary Transformer) each of
capacity 31.5 MVA, 33kV/6.9kV are included in the system.
Figure 13: Flow of Electric Power from Generating station to Consumers

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ELECTRIC GENERATOR
The transformation of mechanical energy to electrical energy is carried out by generator. The
generator used is three phase synchronous generator or alternator. Alternator is based on the
principle of electromagnetic induction and consists of a stationary part stator, and rotating part
rotor. The stator houses the armature winding and the rotor houses the field winding. A D.C
voltage is applied to the field through slip rings. When the rotor is rotated the lines of magnetic
field cut through the stator windings. This as a result, produces an e.m.f across the stator
windings.
The magnitude of the output e.m.f is given as :
E= 4.44f Nph Ø volt where,
 Nph is number of series turns per phase in stator winding
 Ø is the strength of magnetic field in Weber
 f is the frequency of e.m.f generated in Hertz
Again f =
𝐍𝐬𝐱𝐏
𝟏𝟐𝟎
Hz where, Ns= Synchronous speed of the machine in r.p.m
P= number of poles
Stator:
The stator body is designed to withstand internal pressure of hydrogen-air mixture without any
residual deformation. The stator core is built up of segmental punching of high permeability, low
loss CRGOS steel and are in interleaved manner on spring core bars to reduce heating and eddy
current loss. The stator winding has 3 phase double layer short corded bar type lap winding
having 2 parallel paths. The winding bars are insulated with mica thermosetting insulation tape
which consists of flexible mica foil, fully saturated with a synthetic resin having excellent
electrical properties. Water cooled terminal bushings are housed in the lower part of the stator on
the slip ring side.
Rotor:
Rotor is of cylindrical type shaft and body forged in one piece from chromium nickel
molybdenum and vanadium steel. Slots are machined on the outer surface to incorporate
windings. Winding consists of coil made from hand drawn silver copper with bonded insulation.
Generator casing is filled up with H2 gas with required pressure. Propeller type fans are mounted
on either side of rotor shaft for circulating the cooling gas inside the generators.

22. Page | 21
Figure 14: Design of Alternator Stator and Rotor
 Specifications of Generator:
 Make: BHEL
 Type: 3phase Double Star, Synchronous Generator
 Rated Capacity: 210 MW
 Rated Output: 247 MVA
 Rated Terminal Voltage: 15.75 kV
 No. of Rotor Poles: 2
 Rotor voltage supplied: 310V, D.C
 Synchronous Speed: 3000 rpm
 Casing H2 gas pressure: 3.3 to 3.5 kg/cm2

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TRANSFORMERS
A transformer is a static alternating electromagnetic device that transfers electrical power
between two or more circuits using electromagnetic induction. Here the transformers are used to
step up the voltage from 15.75kV to 220kV or 400kV that are provided to the national grid. The
voltage is stepped up in order to reduce the value of current which correspondingly reduces the
Ohmic loss (I2
R) during transmission.
Figure 15: Cross-section of Industrial Transformer
Generating Transformer (GT):
This is a type of Power Transformer where the LV winding is connected to the generator through
the bus duct and HV winding to the transmission system. In addition to the features of Power
Transformers, GT is designed to withstand over voltage caused by sudden load throw off from
the generator. It is built as a single or three phase unit and located in power stations. Normally
generating voltage is 15.75KV from generator. If we want to transmit that power to 220 or
400kV busbar. This voltage must be stepped up, otherwise if we transmit at same voltage level as
generation voltages that is associated with high transmission loss so the transformer which is
used at generator terminal for stepping up the voltage is called Generating transformer
 Specifications of GT:

24. Page | 23
 Make: BHEL
 Number: One for each unit
 Rating: 125/175/250 MVA
 Voltage: 15.75kV(LV side) and 220/400kV(HV side)
 Type: Step Up
 Vector Group: Ynd1
Unit Auxiliary Transformer (UAT):
Unit Auxiliary Transformer is the power transformer that provides power to the auxiliary
equipments of a power generating station during its normal operation.
 Specifications of UAT:
 Make: BHEL
 Number: Two for each unit
 Rating: 16MVA
 Voltage: 15.75kV(HV)/6.6kV(LV)
 Type: Step Down
Station Auxiliary Transformer (SAT):
Station Auxiliary Transformers are used to provide backup power to the auxiliary equipments in
case the UAT fails.
 Specifications of SAT:
 Number: Two (SAT-I, SAT-II)
 Rating: 31.5MVA, 22.05MVA
 Voltage: 33kV(from IBT), 6.9kV(to reverse bus)
 Type: Step Down
Inter Bus Transformer (IBT):
IBT works as a inter connector transformer between two system voltages, i.e 220kV of Stage I
and 400kV of Stage II. Power can flow from either side as per requirement of the grid.
 Specifications of IBT:
 Rating: 105 MVA, Single phase
 Primary Voltage: 400kV
 Secondary Voltage: 220kV
 Tertiary Voltage: 33kV
SWITCHYARD

25. Page | 24
A switchyard may be considered as a junction point where electrical power is coming from one
or more sources and is going out through one or more circuits. This junction point is in the form
of a high capacity conductor spread from one end to the other end of the yard. As the switchyard
handles large amount of power, it is necessary that it remains secure and serviceable to supply
the outgoing transmission feeders even under conditions of major equipment or bus failure.
There are different schemes available for bus bar and associated equipment connection to
facilitate switching operation.
The basic components of a switchyard are as follows:
Circuit Breaker:
A circuit breaker is an equipment that breaks a circuit either manually or automatically under all
conditions at no load, full load or short circuit. Oil circuit breakers, vacuum circuit breakers and
SF6 circuit breakers are a few types of circuit breakers.
Isolator:
Isolators are switches which isolate the circuit at times and thus serve the purpose of protection
during off load operation.
Current Transformer:
These transformers used serve the purpose of protection and metering. They are connected in
series between the line and the instrument. In electrical system it is necessary to
 Read current and power factor
 Meter power consumption.
 Detect abnormalities and feed impulse to protective devices.
Potential Transformer:
Potential Transformers are a type of parallel connected transformers instrument transformers,
used for metering and protection in high voltage circuits or phase shift isolators.
Lightning Arrester:
A lightning arrester is used to protect the electrical devices from damaging effect of lightning. It
limits the surge voltages by bypassing surge current.
Busbar:
In electrical power distribution, busbar or bus is a conductor whose terminal voltage and
frequency of the voltage remains constant. It is made of thick strip of copper or aluminum that
conducts electricity.
Wave Trap:

26. Page | 25
Power plants and substations are connected by high voltage transmission lines which are also
used to carry communication and control signals for the grid. Wave trap filters are used to
separate the power and communication signals at the receiving end.
Figure 16: Typical layout of components in a Switchyard
Switchgear:
In an electric power system, switchgear is the combination of electrical disconnects
switches, fuses or circuit breakers used to
control, protect and isolate electrical
equipment. Switchgear is used both to de-
energize equipment to allow work to be done
and to clear faults downstream. This type of
equipment is important because it is directly
linked to the reliability of the electric supply.
Figure 17: Part of a large Switchgear Panel

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POWER EVACUATION SYSTEM
Power evacuation is a critical function that allows generated power to be immediately evacuated
from the generating station to the grid for distribution.
For evacuation of 400kV power, single Jirath Feeder (capacity 600MW), single Arambagh
Feeder (capacity 600MW) and single Durgapur Feeder (not yet completed) have been provided.
For evacuation of 220kV power, double Howrah Feeder (180MW each), double Haldia Feeder
(90MW each), Tamluk Feeder and double Kolaghat Feeder (90MW each) are provided. The
Kolaghat and Tamluk Feeders are connected with 132kV bus. To increase the capacity of the
Kolaghat and Tamluk feeders, a 220kV/132kV autotransformer (150MVA) has been installed.
Figure 18: Approximate single-line-diagram of Power Evacuation System at KTPS

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CONCLUSION
The vocational training had been conducted in a very efficient way. We have acquired through
knowledge about generation and evacuation of power. Kolaghat Thermal Power Station being
one of the oldest and largest power stations in Eastern India, has been acting as a pioneer in
power generation for decades.
KTPS governs the power generation for Industrial and Commercial requirements and attenuate
the economic as well as social well-being of humankind.
We have carried out this training under well experienced and highly qualified engineers of
KTPS, WBPDCL from various departments viz. Mechanical, Electrical, Chemical, Control and
Instrumentation Departments. Although this is a very old power station, the machines and
instruments are still properly functional due to proper maintenance and skillful handling. I was
able to acquire practical knowledge of the industry about some theoretical engineering studies.
This project report covers the mechanical overview, electrical overview and various cycles and
processes of power generation required in a thermal power plant.

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BIBLIOGRAPHY
 List of Websites:
 www.wbpdcl.co.in
 www.wikipedia.org
 www.regenpowertech.com
 www.power-eng.com
 List of Books:
 Power Plant Engineering by P.K Nag
 Power System Engineering by Nagrath and Kothari
 Electrical Machinery by Dr. P.S. Bimbhra
 Kolaghat Thermal Power Station, Operation Manual