ABOUT NATIONAL THERMAL POWER PLANT COOPERATION, BARH

N.T.P.C. Is India's most imposing power-creating group with it is present yield being 2,500MW.

Around 3,300MW of coal-created power is almost always included at Barh close Patna in Bihar,

India. The several unit 1,980MW Barh I are once again being constructed by Russian firm

Technopromoexport(TPE), & the two-unit 1,320MW Barh II enlargement are being fabricated by

BHEL. Barh has been named a mega power undertaking & is possessed by Indian life association

N.T.P.C.

TableA. ABOUT NATIONAL THERMAL POWER COOPERATION, BARH

Capacity 3300MW-first stage(3x600) and second stage

(2x660)

Estimated cost of the Project 16034cr.(approx.)

Land required Main plant and township 1268 acres, ash dyke

and other 1906 acres

Requirement of coal 17.72 metric ton per year

Sources of Coal Amrapali Block north karnapura coal field

Sources of Water From Ganga River(180qc)

Benefices State Bihar and other States/ North and west union

territories

N.T.P.C.'s BARH(BIHAR) MEGA PROJECT STAGE-II

The 2x660MW feature voyage of N.T.P.C.'s mega-power credit at Barh closer to Patna, province

was started with summat contribution is pegged at Rs 7340 crores. The essential 660MW unit

donate be requisitioned in Dissent 2012 & the backing 660MW thing endownment be charged in

January 2013.

Barh stage-I started in February 2005 is 3x660MW yet is markedly tardy calender chiefly in light

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of long-standing contractual debates between N.T.P.C. & the Russian go hand in hand with

Techno prom fare(T.P.E.) which is the turnkey fasicle for the straight. T.P.E. Is supplying the boilers

& different Slavic partner Nation Machines is supplying the turbine-generators. Organisation 1 was

supposed to single been sactioned by Marching 2009 yet the genius suspected commonplace is Jan

2011.

The different two units are likewise put off by over two geezer hood. The numerate cost of Stage-I

is Rs 8700 crores, of which harshly Rs 3000 crores has of now been spent. Generous supplying for

the rigging protest is most gross yet erection action yet to Solon.

For the ultimo few months,N.T.P.C has been in discourse with TPE to sort out the debates over

quality & case accelerations & obtain work continued at the locale. At the same time there has been

no discovery & Jairam Ramesh declared that N.T.P.C. Has now conceeded chance to TPE Soil Sept

24th before it begins settling processes as accomodated in the captivate.

TABLEB. STRUCTUREOF ORGANISATION

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Table No.C RESPONSIBILITY & AUTHORITY

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FIGUREA. THERMAL POWER PLANTS OF INDIA

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ABOUT PROJECT

CHAPTER 1. PARTS OF THERMAL POWER PLANT

FIGURE1.1VARIOUS PARTS OF THERMAL POWER PLANT

The various parts are listed below-

1.Cooling Tower

2.Cooling water pump

3.Transmission line(3 phase)

4.Unit transformer(3 phase)

5.Electric generator(3 phase)

6.Low pressure turbine

7.Condensate extraction pump

8.Condenser

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9.Intermediate pressure turbine

10.Steam governor valve

11.High pressure turbine

12.Deaerator

13.Feed Water Heater

14.Coal conveyer

15.Coal hopper

16.Pulverised fuel mill

17.Boiler drum

18.Ash hopper

19.Super heater

20.Forced draught fan

21.Reheater

22.Air intake

23.Economiser

24.Air preheater

25.Precipiator

26.Induced draught fan

27.Flue gas

1.COOLING TOWER-

Cooling towers are heat removal devices used to transfer process waste heat to the

atmosphere.Cooling towers may either use the evaporation of water to remove process heat and

cool the working fluid to the near wet bulb temperature or in the case of closed circuit dry cooling

towers rely solely on air to cool the working fluid to the near dry-bulb air temperature. Common

applications include cooling the circulating water used in oil refineries, chemical plants, power

stastion and building cooling.

The towers vary in size from small roof-top units to very large hyperboloid structures that can be

upto 200 metres tall and 100 metres in diameter, or rectangular structure that can be over 40 metres

tall and 80 metres long. Smaller tower are normally factory-built, while larger one are constructed

on the site. The absorbed heat is rejected to the atmosphere by evaporation of some of the cooling

water in mechanical forced-draft or induced draft tower as or in natural draft hyperbolic shaped 6

cooling towers seen at most nuclear power plant.

2.COOLING WATER PUMP-

It pumps the water from the cooling tower which goes to the condenser.

3.THREE PHASE TRANSMISSION LINE-

Three phase electric power is acommon method of electric power transmission. It is a type of

polyphase system mainly used to power motors and other devices. A three phase system use less

conductive material to transmit electric power than equivalent single phase, two phase, or direct

current system at the same voltage. In a three phase system, three circuit reach at their

instanteneous peak at different time.

Taking current in one conductor as the reference , the current in the other two are are delayed in

time by one-third and two-third of the one cycle. This delay between “phases” has the effect of

giving constant power transfer over each cycle of the current and also makes it possible to produce

a magnetic field in the electric motor. At the power stastion the electric generator converts the

mechanical power into electric currents, one from each electromagnetic coil or winding of the

generator.

The current are sinusoidal functions of time, all the same frequency but offset is time to give

different phases. In a three phase system the phases are spaced equally,giving a phase separation of

one-third of one cycle. Generator output that ranges from hundred of volts to 30,000volts.

4.UNIT TRANSFORMER(3 PHASE)-

At power station, transformer step-up this voltage to one more suitable for transmission. After

numereous further conversion in the transmission and distribution system the power is finally

transformed to the standard mains voltage (i.e., household voltage). The power have already been

split up into single phase at this point or it may still been in three phase. Where the step-down is 3-

phase, the output of transformer is usually star connected with the standard mains voltage being the

phase neutral voltage.

5.ELECTRICAL GENERATOR-

An electrical generator is a device that converts kinetic energy into electrical energy generally use

electromagnetic induction. The task of converting the electrical energy into mechanical energy is

accomplished by using a motor. The source of energy can be water falling through a turbine or

steam turning a turbine. The most common speed for generator is 3000 rad/s for 50 Hz.

6.LOW PRESSURE TURBINE-

Energy in the steam after it leaves the turbine is convert into rotational energy as it passes through 7

the turbine. The turbine normally consists of several stages with each stage consisting of a

stationary blade(or nozzle) and a rotating blade. Stationary blades converts the potential energy of

steam into kinetic energy and direct the flow onto the rotating blades. The rotating blades convert

the kinetic energy into impulse and reaction forces, caused by pressure drop, which results in the

rotation of turbine shaft. The turbine shaft is connected to the generator, which produces the

electrical energy.

Low Pressure Turbine(LPT) consist of 4x2 stages. After passing through Intermediate Pressure

Turbine steam is passed to through the LPT.

7.CONDENSATION AND EXTRACTION PUMP-

A Boiler feed pump is aspecific type of pump used to pump water into steam boiler. The water may

be freshly applied or returning condensation of the steam produced by the boiler. These pumps are

normally high pressure unit that use suction from a condensate return system and can be of

centrifugal pump type or positive displacement type.

8.CONDENSER-

The steam coming from LPT is brought into thermal contact with cold water in the condenser,

where it condenses back into water creating near vacuum like conditions inside the condenser

chest.

9.INTERMEDIATE PRESSURE TURBINE-

In Intermediate Pressure Turbine(IPT) consists of 11 stages. When the steam has been passed

through HPT it enters into IPT. IPT has two ends- rear and front. Steam enters through front end

and exits through rear end.

9.STEAM GOVENOR VALVE-

The pump was often a positive displacement pump that had steam valves and cylinders at one end

and feed water cylinder at other end, no crankshaft was required. In thermal power plant the

primary function of surface condenser is to condensate the exhaust steam from a steam turbine to

obtain the maximum efficiency and also to convert the turbine condensate steam into pure water so

that it can be reused in the steam generator or boiler as boiler feed water. By condensing the

exhaust steam of a turbine at a pressure below atmospheric pressure, the steam pressure drop

between inlet and exhaust is increased, which increases the amount of heat avaliable for conversion

into mechanical energy. Most of the heat liberated due to condensation of exhaust steam is carried

away by cooling mechanism used by the surface condenser. Control valves are the valves used

within the industrial plants and elasewhere to control operating conditions such as temperature, 8

pressure, flow and liquid level by fully or partially opening or closing in response to signal

received from controllers that compares a”set point” to a “process variable” whose value is

provided by means of mechanical, electrical, hydraullic or pneuamatic system.

11.HIGH PRESSURE TURBINE-

Steam coming from Boiler directly feeds into HPT at a temperature of 540 C.and at a pressure of

136kg/cm2. Here it passes through 12 different stages due to which the temperature goes down

down to 329C and pressure as 27kg/cm2. This line is also known as CRH-COLD REHEAT LINE.

12.DEAREATOR-

A Deareator is a device for air removal and used to remove dissolved gases from boiler feed water

to make it non-corrosive. A deareator typically includes a vertical domed deareation section as the

deareation boiler water tank. A steam generating boiler requires that the circulating steam,

condensate and feed water should be devoid of dissolved gases, particularly corosive ones and

dissolved or suspended solids. The gases will give rise to corrosion of the metal. The solid will

deposit on the heating surfaces giving rise to localized heating and tube rupters due to over heating.

13.FEED WATER HEATER-

A Feed water heater is a power plant component used to preheat water delivered to avsteam

generating boiler. Preheating the feed water reduces the irreversibility involved in the steam

generation and therefore improves the thermodynamic efficiency of the system. This reduces plant

operating costs and also to avoid thermal sock to the boiler mounted metal when the feed water is

introduced back into the steam cycle. In a steam power, feed water heaters allow the feed water to

be brought upto the saturation system very gradually. This minimizes the inevitable irreversibility

associated with heat transfer to the working fluid.

14.COAL CONVEYOR-

Coal conveyor consists of two pulleys which are used to transfer coal from its storage place to coal

hopper. A belt conveyor consist of two pulleys, with a continuous loop of material- the conveyor

belt- that rotates about them. The pulleys are powered , moving the belt and the material on the belt

forward.

Conveyor belts are extetensively used to transport industrial and agricultural material, such as

grains, coal, ores etc.,

15.COAL HOPPER-

Coal Hoppers are the places which are used to feed coal to Fuel Mill. It also has the arrangement of 9

entering the Hot air at 200C inside it which solves our two-purposes-

a. If our coal has moisture content then it dries it so that a proper combustion takes place

b. It raises the temperature of coal so that its temperature is more near to its Ignite temperature so

that combustion is easy.

16.PULVERISED FUEL MILL-

A pulveriser is a device for grinding coal for combustion in a furnance in a fossil fuel power plant.

17.BOILER DRUM-

Steam drums are a regular feature of water tube boilers. It is a reservoir of the water/steam at the

top of the water tubes in water-tube boiler. They store the steam generated in the water tubes in the

water=tube boiler. They store the steam generated in the water tubes in the water tube and acts as a

phase separator for the steam/water mixture. The difference in densities between hot and cold water

helps in accumaltion of the hotter water/and are saturated steam drum. Made from high grade-steel

probably stainless and its working involves temperature of 390C and pressure well above

350psi(2.4MPa). The seperated steam is drawn off the drum. The steam will renter the furnance in

through a super heater, while the saturated water at the bottom of steam drum flows down to the

mud-drum/feed water drum by down comer tubes. Accessories include a safety valve, water level

indicator and fuse plug.

18.ASH HOPPER-

A steam drum is used in the company of amud-drum/feed water drum which is located to a lower

level.

So that it acts as a sump for the sludge or sediments which have tendency to accumalates at the

bottom.

19.SUPER HEATER-

A Super Heater is a device in a steam engine that heats the steam generated by the boiler again

increasing its thermal energy. Super heaters increase the efficiency of the steam engine, and were

widely adopted. Steam which has been superheated is logically known as superheated steam; non-

superheated steam is called saturated or wet steam

20.FORCED DRAUGHT FAN-

External fans are provided to give sufficient air for combustion. The forced draught fan takes air

from the atmosphere and, warms it in the air preheater for better combustion, injects it via the air

nozzles on the furnance wall.

21.REHEATER-10

Reheater is a heater which is used to raise the temperature of steam which has fallen from the

intermediate pressure turbine.

22.AIR INTAKE-

Air is taken from the environment by an intake tower which is fed to the fuel.

23.ECONOMISERS-

Economizer, are the mechanical devices that intend to reduce energy consumption, or to perform

another useful function like preheating a fluid. The term economizer is used for other purposes as

well-boiler, power plant, heating, ventilating, and air-conditioning. In boilers, economizer are heat

exchange devices that heat fluids, usually water, up to but not normally beyond the boiling point of

the fluid. Economizers are so named because they can make use of the enthalpy and improving the

boiler's efficiency.

24.AIR PREHEATER-

Air preheater is a general term to describe any device designed to heat air before another process.

The purpose of the air preheater is to recover the heat from the boiler flue gas which increases

thermal efficiency.of the boiler by reducing the useful heat lost in the flue gas. As a consequence,

the flue gases are also sent to the flue gas stack(or chimney) at a lower temperature allowing

simplified design of the ducting and the flue gas stack. It also allows control over the temperature

of gases leaving the stack.

25.PRECIPITATOR-

An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device

that removes particles from a flowing gas (such as air) using the force of an inducedelectrostatic

charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the

flow of gases through the device, and can easily remove fine particulate matter such as dust and

smoke from the air stream.

In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP

applies energy only to the particulate matter being collected and therefore is very efficient in its

consumption of energy (in the form of electricity).

26.INDUCED DRAUGHT FAN-

Induced-draft or forced-draft burners increase the efficiency of the furnace over natural-draft

burners. Let's make sure we understand the terms.1.Natural-draft burners

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A natural-draft burner relies simply on atmospheric pressure and the venturi effect of the gas

burner to move the air. Excess air has to be available both at the burner and at the draft hood to

ensure full combustion and good draft as it moves up the chimney. With natural draft (also

sometimes called gravity venting), we have to keep the chimney warm enough to maintain the

upward flow of exhaust products. The pressure in the venting system is negative with natural draft

burners.

2. Induced-draft

An induced-draft burner uses a blower to pull air into the burner, and through the combustion

chamber and heat exchanger. The fan then pushes the flue gases out through the vent. This creates

negative pressure in the furnace, and may create positive or negative pressure in the venting

systems.

Sidewall-vented, induced-draft furnaces have significant positive pressure pushing exhaust gases

outside. Induced-draft furnaces designed to vent into chimneys or B- vents, for example, are

baffled so the exhaust gases are at atmospheric pressure (considered negative) when they enter the

chimney. These can then be manifolded with natural-draft water heaters, for example. Sidewall-

vented systems cannot.

Induced-draft fans are also called aust blowers, power vents or power venters. Systems with

induced or forced draft fans are sometimes referred tofan-assisted. 3. Forced-draft burners A

forced-draft combustion system uses a fan to push combustion air into the burner, through the

combustion chamber, through the heat exchanger and out through the vent system. All oil burners

and some gas systems use forced draft. Forced-draft burners cannot usually be manifolded with

any other type of burner, although two forced-draft burners can be coupled. Some forced draft

systems produce negative vent pressure (conventional oil fur-nace, for example) and some produce

positive vent pressure (high efficiency gas furnaces,

27.FLUE GAS-

Flue gases the waste gases exhausted out through the chimney of the boiler.

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CHAPTER2. TYPES OF CYCLES USED DURING THE PROCESS

FIGURE.2.1. SHOWING THE WHOLE PROCESSES USED AT THERMAL PLANT

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TYPES OF CYCLES-

1.Coal Cycle

TABLE2.1. COAL CYCLE

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2.Flue Gas Cycle

TABLE2.2 FLUE GAS CYCLE

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3.Primary Air Cycle

TABLE2.3.PRIMARY AIR CYCLE

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4.Secondary Air Cycle

TABLE NO.2.4. SECONDARY AIR CYCLE

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5.Electricity Cycle

TABLE NO.2.5. ELECTRICITY CYCLE

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6.Condensate Cycle

TABLE NO.2.6. CONDENSATE CYCLE

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7.Feed Water Cycle

TABLE NO.2.7. FEED WATER CYCLE

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8.Steam Cycle

TABLE NO.2.8. STEAM CYCLE

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CHAPTER 3.PROCESS OF GENERATION OF ELECTRICITY

3.1. STEPS OF GENERATION OF ELECTRICITY-

There are 3 steps of generation of electricity-

1. Coal to Steam

2. Steam to mechanical powers(turbines)

3. Power generation, transmission & distribution

FIG.3.1.PROCESS OF GENERATION OF ELECTRICITY

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FIG.3.2.SUMMARY OF COAL TO ELECTRICITY PROCESS

3.1.A. COAL TO STEAM-

I.COAL HANDLING PLANT(C.H.P.)-

Coal handlig plant is a plant which handles the coal from its reciept through the coal mines to

transporting it to boiler and store in bunkers. It also processes the raw coal to make it suitable for

boiler operation.

A typical coal handling plant in any power plant shall have following processes in sequence

depending upon the capacity of the plant.

1.Unloading process

2.Feeding process

3.Screening process

4.Crushing process

5.Stacing process

6.Reclaiming process

7.Bunkering process

II.BOILERS-

WORKING PRINCIPLE-MODIFIED RANKINE CYCLE-

Process1-2- working fluid is pumped from low to high pressure.

Process2-6- high pressure fluid enters a boiler where it is heated at constant pressure by an external

heat source to become saturated dry pressure

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Process6-11- The dry saturated vapour expands through a turbine,dry pressure

Process11-1- The wet vapour then enters a condenser where it is condensed at a constant

temperature to become a saturated liquid

FIG3.3. MODIFIED RANKINE CYCLE

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FIGURE 3.4.VARIOUS VIEWS OF BOILER

(A)

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(B)

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©

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(D)

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(F)

3.1.B.STEAM TO MECHANICAL POWER(TURBINE)

There are 3 types of turbines-

I.HIGH PRESSURE TURBINE-

• It is of single design..

• Each stage has moving and stationary blades

• Superheated steam (at 110C) from boiler drum enters in to it.

• Speed- 3000r.p.m.

II.INTERMEDIATE PRESSURE TURBINE-

• Double flow design with seven stages of blading on either side.

• Each stage has moving and stationary blades.

• Reheated steam(at 535C) from H.P. Turbine outlet enrers to it.

• Speed- 3000rpm

III.LOW PRESSURE TURBINE-

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• It also consists of douuble flow design with 6 stages in front and rear flow vpaths.

• Each stage has moving and stationary blades.

• Steam out of I.P. Turbine directly enters in to it.

• Speed- 3000rpm

FIGURE3.5. CONDENSER

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3.1.C.POWER GENERATION, TRANSMISSION AND DISTRIBUTION-

TRANSFORMER-

TABLE 3.1. ABOUT TRANSFORMER

Rating Continuous

Active output 110MW

Rated Voltage 11000+/-5%V

Rated Current 7220A

Power Factor 0.8% lagging

Frequency 50Hz

Excitation System Static type

Field current at rated output 1335A

Type of cooling system Hydrogen Cooled

Hydrogen Pressure 2 Ata

No. of H cooled elements 6

Cooling medium for H Soft Water

SWITCH YARD-

Electrical energy can be transmitted through-

a. Indoor Equipments

b.Outdoor Equipments

a.INDOOR EQUIPMENT-

1.Bus Bar

2.Lightening Arrester

3.Wave Trap

4.Breaker

5.Capacitive voltage transformer

6.Earthing rod

7.Current transformer

8.Potential transformer

9.Lightening mask

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b.OUTDOOR EQUPMENT-

1.Relays

2.Control panels

3.Circuit breakers

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CONCLUSION AND FUTURE SCOPE-

• REGARDING N.T.P.C.-

The thermal power project of Barh is mainly for the fulfillment of the electricity needs of the

eastern grid and the Bihar along with its neighbouring states.

On the account of future scope, this project has a lot of scope as it will provide-

1.Electricity needs

2.Jobs to local people

3.Lessing load on eastern grid

4.Support in industrialization of beneficial areas

5.Support in development of Bihar 6.Better

use of conventional resources like coal which comes from JHARIA mines situated at

Jharkhand

• REGARDING MECHANICAL STUDENT-

The thermal power plant pf N.T.P.C., Barh helped a lot in improvement as far mechanical skill is

considered, there was opportunity as far as mechanical skill is considered, there was opportunity

provided to watch all the components we used in steam generation process, thermal engineering,

heat transfer and other topics related to the course book. There we got chance to see the practical

application of the various equipments like boilers, turbines etc.., It also provided me an opportunity

to get training ina power plant project with actual environment and several trainee through various

institutes which will definetly help me to understand the working atmosphere of the company.

• COMBINED CONCLUSION-

So on the basis of above mentioned facts I think this was really a beneficiary training regarding my

career.

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RESULT AND DISCUSSION-

The main purpose of the NATIONAL THERMAL POWER COOPERATION, BARH plant is to

produit is estimated that ce the electricity with the help of various mechanical, electrical &

electronics equipments. Currently the stage1 is to produce electricity only. Soon after the

completion of power plant it is estimated that the requirement of electricity will come to be

fulfilled in the eastern grid and also in Bihar and neghbouring states.

The capacity of the power plant is 33,000MW but right now only stageI is to be start and stageII is

still under construction. The stageI consists of 3 boilers while stage II consists of 2 boilers. So,

right now the NATIONAL THERMAL POWER PLANT, BARH is to work on just 60% of its

capacity.

The frequency of grid is 50Hz on 220V, the grid can work within the range of 47.5Hz to 52.5Hz

the grid will collapse and there will be power-cut problem and this condition is termed as

“BLACKOUT”.

Earlier days many private companies used to hide their production to make profit and had to

supply excess electricity sometimes to save the grid, but now-a-days excess electricity sometimes

to save the grid, but now-a-days government has made a rule that-”It is mandatory for all the grids

to produce or hide only maximum of 5% of the total capacity declared by the grid”.

• RESULT -

NATIONAL THERMAL POWER COOPERATION is leading electricity producing government

organisation of India, on the account of training there was a lot of opportunity to learn in terms of

Mechanical(Boiler, turbines etc.,), Electrical(Transformer, Switch yard etc..,),Electronics(Various

equipments and their work) etc.., it was a unforgettable and beneficiary stay.

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