A

Seminar Report

on

KALI SINDH THERMAL POWER PROJECT, JHALAWAR Submitted to:

GLOBAL TECHNICAL CAMPUS, JAIPUR

2015-16

Submitted To: . Guided by Submitted By:Ms. EKTA SHARMA Mr. O.P. KUMAVAT & NEERAJ PATIDAR(H.O.D.) Mr. MANISH SHRIVASTVA 4th Yr.EE Dept.OfElectrical Engg Asst. professor EE Dept Roll No.-12EGJEE733

.DEPARTMENT OF ELECTRICAL ENGINEERING

[1]

ACKNOWLEDGEMENTIt gives me an immense pleasure to complete the training report of KALISINDH

THERMAL POWER PROJECT. I would like to express my gratitude towards the team

of KaTPP. The experience and knowledge that I have gained from KaTPP will always be

motivating and guiding factor in my career to grow as a good professional engineer.

I would sincerely like to thank my training report guide, Mr. MANISH

SHRIVASTVA and Mr. O.P.KUMAWAT for providing me the valuable knowledge

and giving their constructive feedback.

I would also like to thank Mrs. EKTA SHARMA (HOD, Dept. of EE) for the

encouragement and their support.

NEERAJ PATIDAR 4th Year EE

12EGJEE733

[2]

PREFACE

In today’s world, electricity has an important role. Today Electricity contributes the

largest share to a country’s economic growth. It is the most powerful resource and has

brought industrial revolution worldwide. It has resulted in social changes too and raised

the standard of living. In India, several organizations like NHPC, NTPC, POWER GRID,

and other state electricity boards etc. are engaged in electricity generation. RRVUNL is

one of the largest among these with an honorable Contribution.

The rise in civilization is closely related to improvements in transportation and

requirement of energy that is not readily available in large quantities but is also readily

transportable. There are several source of energy in world in which thermal power plant

is also a source of energy. It give electrical energy. A very peculiar fact about electrical

energy is that neither it is directly available in nature nor it is directly used finally in this

form, yet it is so widely produced and is the most popular high grade energy.

The purpose behind training is to understand the difficult concepts in a better

way with gain of knowledge. Report starts with a brief introduction of KaTPP.

While writing the report and while i was on my training i was wondering that

Science and technology are as ever expanding field and the engineers working hard day

and night and make the life a gift for us.

NEERAJ PATIDAR 4th Year EE

12EGJEE733

[3]

CONTENTS

S.NO. TITLE PAGE NO.

FRONT PAGE ....

CIRTIFICATE FROM ORGANIZATION ....

COLLEGE CERTIFICATE .....

ACKNOWLEDGMENT ….

ABSTRACT .....

PREFACE ….

TABLE OF CONTENTS .....

LIST OF FIGURES ......

LIST OF TABLES ......

1. CHAPTER 1: INTRODUCATION………...…………………………… 01-08 1. INTRODUCATION..........................................................................…...01

1.1. INTRODUCATION OVERVIEW OF KaTPP…………….......….…...031.2. ENERGY GENERATED IN KaTPP………...…….….……......…….. 051.3. PLANT OVERVIEW……………………………….…..…..…....…… 061.4. PRINCIPLE OF OPERATION…………….......................................... 061.5. THERMAL PLANT OPERATION PROCEDURE……….……....…..061.6. PULVERSIZED COAL FUELED POWER PLANT….………………08

2. CHAPTER 2 : COAL HANDLING PLANT (CHP)…………………… 10-112.1. INTODUCATION………….………………..…………………..……. 102.2. STAGES OF COAL HANDLING PLANT…………….…….............. 11

3. CHAPTER 3 : IMPORTANT PARTS OF THERMAL POWER PLANT.............................................................................................................15-23

3.1. BOILER……………………………………………………..……….... 153.2. TURBINE………………………………….…………….……….….....163.3. GENERATOR………………………….……………….…………...... 193.4. CONDENSER…………………………..…………………………..… 213.5. COOLING TOWER………………………….……………………….. 21

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3.6. WATER TREATMENT PLANT……………………...…………...…. 23

4. CHAPTER 4 : ESP AND AHP SYSTEM………………………………… 26-304.1. ELECTROSTATIC PRECIPITATOR (ESP)……………………….... 264.2. ASH HANDLING PLANT (AHP)……….…………………………....30

5. CHAPTER 5 : CONTOLLING AND TRANSMISSION SYSTEM……. 32-395.1. CONTOL AND INSTRUMENTATION SYSTEM………..….….….. 325.2. CONTROL ROOM…………………………………………………… 365.3. AUXILLARY SUPPLY ……………………………………………… 375.4. SWITCHYARD ………………………………………………...…….39

6. CHAPTER 6: EFFICIENCY AND CONCLUSION…………………………466.1. EFFICIENCY…………………………………………………….….... 46

CONCLUSION……………………….………………………………………….… 47

REFRENCE…………………….………………………………………………….. 48

[5]

LIST OF FIGUREFIG.NO

.

FIG.NAME PAGE NO.

1. General layout : Thermal power plant 1

1.1 Percentage of electricity produced by different sectors 2

1.2 Overview of KaTPP 3

1.3 Operation principal 6

1.4 Pulverized coal fueled power plant 8

2.1 Coal handling plant 14

3.1 Boiler 15

3.2 Turbine 17

3.3 Generator 19

3..5 Cooling Tower 22

4.1 Electrostatic Precipitation Unit 30

4.2 Fly ash system 31

5.3 Switching and transmission 38

5.4 Overview of switchyard 45

LIST OF TABLES.NO. TITTLE PAGE NO.

1.3 Plant overview 5

2.1 Coal handling detail 11

[6]

2.2 Crusher /ring granulator Specification 12

3.2 Turbine Specification 18

3.3 Generator specification for unit i and ii 20

3.4 Diesel generator 20

ABSTRACT

A steam-electric power station is a power   station in which the electric generator

is steam driven. Water is heated, turns into steam and spins a steam turbine. After it

passes through the turbine, the steam is condensed in a condenser. The greatest variation

in the design of steam-electric power plants is due to the different fuel sources.

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 alloted 1200 mcft water for the project from proposed

Kalisindh dam. The existing Dam is located at Bhawarasa village, primarily for P.H.E.D.

purpose is being uplifted for providing a storase of 1200mcft water for this power

project. The GOR has alloted 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

[7]

dt.09/07/08, through ICB route at cost Rs.4900 Crores. Ministry of coal, Govt. of India

has alloted ‘Paras east and Kanta basin ‘ coal blocks to RVUN in Chhatisgarh 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

[8]

CHAPTER - 1

INTRODUCATION 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? How the chemical energy

stored in fuel is converted into heat energy which forms the input of power plant i.e.

steam and electrical energy produced by generator? Power is the single most important

necessity for common people and industrial development of nation. In a conventional

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 place in Boiler or Steam Generator, second in

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 rotates the turbine which drives an electrical

generator after that steam pass through in a condenser where it condensed and recycled to

again in boiler; this whole cycle is known as RANKINE CYCLE.

Fig-1: General Layout: Thermal Power Plant

[9]

CONTRIBUTATION OF THERMAL POWER PLANT IN INDIA

In India, Thermal Power Plant contribute about 60% of the total electricity produced.

Pie chart shows the electricity production percentage by different sectors-

Power Installed Capacity = 253.390 GW

As of 31st August 2014

Thermal

176,118.6

MW

Hydro

40,798.8

MW

Nuclear

4,780

MW

Renewable

32,307.71

MW

Total

254,005.1 MW

Fig 1.1-Percentage of Electricity Produced by Different Sectors

[10]

1.1 INTRODUCATION OVERVIEW OF KaTPP

Fig 1.2 -Overview of KaTPP

[11]

Kalisindh Thermal Power Project is located in Jhalawar. The project site is about 12 km

from Jhalawar (Distt.-Head quarter) and NH-12. Site is comprising of 5 villages viz.

Nimoda, Undal, Motipura, Singharia and Devri. It is 2km from state highway No.19 and

8 km from RamganjMandi - 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 11thfive 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 storage of 1200mcft water for this power project.

The GOR has allotted 842 bigha Government land and acquired 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.4900Crores. 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 2x660MW in

next few years.

2*600 KALISINDH THERMAL POWERP ROJECT- JHALAWAR

o OWNER -RVUNLo OWNER’S CONSULTANT - TATA CONSULTING ENERGY LTD.

MUMBAIo EPC - BGR ENERGY SYSTEM LTD.o CONTRACTOR - CHENNAI

[12]

1.2 ENERGY GENERATED IN KaTPP

Number of units=2

Electricity generated by one unit=600 MW

Total electricity negated by plant=2x600=1200 MW

TABLE - 1.3:PLANT OVERVIEW

Project Kalisindh Super Thermal Power Project Jhalawar

Capacity 1200MW(2x600 MW)

Project Site Village-Undel, Motipura, Nimoda, Singhania & Deveri of Tehsil

Jhalarapatan, Distt-Jhalawar

Project Location The project site is about 12 km from NH-12, 2km from state

highway and 8 km from proposed Ramganj Mandi-Bhopal broad

gauge rail line.

Land Area 2230 Bigha/564 Hq.(1400 bigha/350 Hq. in I stage)

Water Source and

quantity

Dam on Kalisindh river and 3400CuM/Hrs.

Fuel Source Main Fuel-Coal from captive coal blocks(Paras east and kanta

Basin in Chhatisgarh state) Secondary Fuel-FO/HSD

Quantity of fuel(at

80% PLF)

Coal-56 Lacs TPA FO/HSD-13000-14000 KL/A

ElectroStatic

Precipator

99.9 % Capacity

Stack Height 275 Mtr

Estimated revised

cost

Rs.7723 Crores

1.3 PRINCIPLEOF OPERATION

[13]

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.

For steam boiler, this would be a reversible constant pressure heating process of

water to form steam.

For turbine,the ideal process would be a reversible adiabatic expansion of steam.

For condenser, it would be a reversible a constant pressure heat rejection as the

steam condenser till it becomes saturated liquid.

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.

Fig 1.3 – Operation principal

1.4 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.

COAL TO STEAM- The coal is burnt at the rate upto 200 tonnes per hour. From

coal stores, the fuel is carried on convey or belts to bunkers through coal tipper. It

then falls in to coal pulverizing mill, where it is grounded into powder as fine as

flour. Air is drawn into the boiler house by drought fan and passed through

Preheaters. Some air is passed directly to bunker and rest, through primary air

[14]

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 spent steam is sent to

condenser, where it turns back to water called condensate. Condensate is sent

tolower 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.

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 upto 3000rpm. At each stage, steam expands, pressure

decreases and velocity increases.

MECHANICAL POWER TO ELECTRICAL POWER- To obtained the

electrical power from mechanical power we connect the shaft to an alternator’s

armature. When the armature is rotated and electric current is produced in the

stator’s windings. The generated electricity is of order 25,000 volts.

SWITCHING AND TRANSMISSION-The produced electricity is can’t to

transmitted as this state so It is passed to a series of three switches called an

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.

[15]

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.

1.5 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 super heat Rankine cycle:

Fig1.4- Pulverized Coal Fueled Power Plant

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

[16]

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. The first energy conversion is

carried in Boiler or steam generator; the second is carried out in Turbine and the last one

carried out in the Generator.

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.

[17]

CHAPTER-2

COAL HANDLING PLANT (C.H.P.)

2.1 INTRODUCTION:

Every thermal power plant is based on steam produced on the expanse of heat energy

produced on combustion of fuel. Coal is categorized as follows depending upon fixed

carbon, volatile matter and moisture content:

Anthracite having 86% fixed carbon

Bituminous having 46 to 86% fixed carbon

Lignite having 30% fixed carbon and

Peat having 5 to 10% fixed carbon

Coal from mines is transported to CHP in railway wagons. It is unloaded in track

hoppers. Each project requires transportation of large quantity of coal mines to the power

station site. Each project is established near coal mine which meets the coal requirements

for the span of its entire operational life. For the purpose each plant has Merry Go-Round

(MGR) rail transportation system. The loading operation of the coal rake takes place

while it is moving under the silo at a present speed of 0.8 Km/hr. the loading time for

each wagon is one minute. For unloading of coal from the wagons an underground track

hopper is provided at the power station.

The term coal handling plant means to store and to handle the coal which is

transported by the train and convey to the bunkers with the help of belt conveyers.

Through the bunkers coal is transferred to the coal mill and drifted to the furnace. The

coal handling plant includes wagon tippler, conveyer belt, crusher house, stacker &

reclaimer, bunkers & coal mill.

COAL SUPPLY IN KaTPP-Ministry of coal, Govt. of India has allotted Paras east and

Kanta basin coal blocks to RVUN in Chhattisgarh state.

[18]

2.2 STAGES OF COAL HANDLING PLANT

WAGON TIPPLER-The term Wagon Tippler contains two words WAGON &

TIPPLER .Wagon means the 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 labors to

dispose it into the hopper.

TABLE – 2.1:Coal handling detail

Capacity 90 tonnes

Types of Tipplers 1.Weighing type,2.Non weighing type

Angle of Tip 30 ‘to35’

Wire Ropes 1.Hoisting Ropes, 2.Counter Weight Ropes

Drive unit Motor 37.3 KW

Operating Cycle 10 wagons/Hour on 1 wagon Tippler

Time consume for one cycle 6 minutes

FEEDER- It is used to control the supply of crushed coal to the mill depending

upon load condition.It is installed under wagon tippler and hopper.In KaTPP there

are 4 unbalanced Motor Vibrating Feeder installed in unit 1st.

CHRUSHER/RING GRANULATOR-In ring granulator the material is fed in to

the crushing chamber and is crushed by the rind hammers with impact and rolling

action across the feed, with concentrated pressure.This cracks the coal producing

a granulator product with a minimum of fines up to 20 mm square.

[19]

TABLE – 2.2:Chrusher /ring capacity

Capacity 500 Tonnes/hr

Machine Weight 30 Tonnes(approx.)

Max Feed Rate 500 Tonnes/hr

Rotor Speed 720 r.p.m

Motor 550 H.P

Volts 606 KV

Phase 3 Phase motor

CONVEYORS-Conveyor belt is used to sent the coal from coal storage yard and

also used to sent crushed coal from store to mill bunkers.The carrying capacity of

conveyors belt is 750 tonnes/hrs that are installed in KaTPP.

Conveyor belt used in coal handling plant(CHP) are of 2 types

1. 5 ply x1000 mm width with 5 mm rubber top side and 5 mm rubber bottom side.

Total thickness of belt:-17 to 18 mm

Power:-1000KN/m2

2. 4 Ply x1000 mm width with 5mm rubber top side and 5 mm rubber bottom side.

Total thickness of belt:-17mm

Power:-800KN/m2

Cold joint are used in joining the conveyor,conveyor belts run with the help of

electric motor ,gear box,fluid coupling geared coupling are installed at head of

allconveyors.

PARTS OF CONVEYORS:

1) Flap Gate-it provide under coal transfer chutes for replacements of

crusher/conveyors.

2) Deflector Plate-Deflector plates are installed in the chutes coming on

conveyors to keep the coal direction in the centre of the conveyors.

[20]

3) Skirt board and Skirt rubber-These are provided on tail end chutes to avoid

spillages of coal from Conveyors.

4) Stone picker-Stone picker pick the stonesfrom the running belt manually.

5) Metal Detactor-Electromagnets are provide on conveyors to avoid and to

save crusher parts and entry of iron pieces in crusher.It also stop the entry of

iron pieces in coal bunker to save damage of coal mills.

6) Guide Idlers-These idlers help to train/guide the conveyors.

7) Return Idlers-These idlers carries the conveyors belts in return side.

8) R.T.I (Return Training Idler)-These idlers are provided on return side to

guide the conveyors.

9) Impact Idler-These Rubber idlers are provided under chutes through which

coal falls on conveyors.

10) Carrying Idlers-These are installed to run the conveyor.

BUNKERS-Bunckers are fabricated to store the coal before sending to coal

mills.Coal is fed in the bunkers with the help of tripper trolleys installed at 37 m

height for unit 1st and 2nd.These are 20 bunkers for unit 1st and 2nd.

Capacity of a bunker=500 tonne/bunker.

COAL BUNKERS-These are in process storage used for storing crushed coal

from the handling system.Generally these are made up of the welded steel plates

with vibrating arrangement of the outlet to avoid chocking of coal, normally there

are six bunker supply coal to the corresponding mills.These are located on the top

of mills so as to add gravity feeding of coal.

[21]

RECLAIM YARD-After filing the coal bunkers extra coal is taken to reclaim

yard after crushing of coal to storage.

COAL CIRCULATION-Coal is transported from the coal mine with the help of

train.Train wagons are emptied with the help of wagon tipplers and sent to the

crusher for crushing.From coal crusher it goes to the bunker through conveyor

belt and from coal bunker it move to R.C feeder feeds coal to the coal mill,where

the coal is ground in to powder from.

Fig2.2-coal handling plant

CHAPTER-3

[22]

IMPORTANT PARTS OF THERMAL POWER PLANT

3.1 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”.

In simple way, boiler is a device used for producing steam. There are two types of boiler

(depending upon tube content):

a) Fire tube boiler

b) Water tube boiler

Here, boiler used is of water type. In the boiler, heat energy transfer takes place through

tube walls and drum. The gases lose their heat to water in the boiler or superheated. The

escape heat is used to heat the water through economizer.

ID and FD fans are used to produce artificial draught. The fuel oil is used to ignite the

boiler and pulverized coal is lifted from the coal mills by PA fans.

Various motors use in boiler are different rating and parameters 32KW,15KW ,11KW & 3.3KW.

Fig 3.1-Boiler

[23]

BOILER AUXILIARIES-Efficiency of a system is of most concerned. Thus it is very

important to maintain a system as efficient as possible. So Boiler auxiliaries help in

improving boiler’s efficiency. Following are the important auxiliaries used

ECONOMISER: 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 increase 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 540 deg.

DRAFT FANS: They handle the supply of air and the pressure of furnace.

BOILER MOUNTINGS-These are used for the safe operation of boiler. Some example

of mountings used are water level indicator in drum, furnace temperature probe, reheat

release valve, pressure gauges indicating steam pressure etc.

3.2 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 givesrise to change of momentum and

therefore to a force. This constitutes a driving force to a turbine.

The passage of them/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

[24]

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 Power

Project N600-16.7/587/537,Re-Het,Three Casing, Four Exhaust, Tandem Compound

Condenser Type Turbine Used.

The turbine is of tandem compound design with separate High

Pressure(HP),Indermediate Pressure(IP) and Low Pressure(LP) cylinders. The HP turbine

is of Single Flow type while IP and LP turbines are of Double Flow type .

The readily designed HP,IP and LP turbines are combined and sized to required

power output,steam parameters and cycle configuration to give most economical turbine

set.The design and constructional feature have proved their reliability in service and

ensure trouble free operation over long operating periods and at the same time ensuring

high thermal efficiencies.

Fig 3.2-Turbine

[25]

TABLE – 3.2: TURBINE SPECIFICATION-

Rated output with extraction flow 600 MW

Speed 3000 r.p.m

Main steam throttle flow at HP Inlet 1848.5 TPH

Main steam pressure to HP turbine inlet 167 kg/sq.cm

Main steam temp. to HP turbine inlet 538 deg.cel

Re-heater steam flow at IP inlet 1587.942 TPH

Re-heater steam temp. at IP inlet 538 deg.cel

Steam pressure at LP inlet 35.12 kg/sq.cm

Steam flow at LP inlet 1353.7 TPH

Rotation Direction(view from turbine) anticlock wise

Number of stages 42

High pressure turbine-

a) Intermediate pressure

b) Low pressure turbine

c) Governing system

1 governing and 8 pressure

5 pressure stage

28 pressure stage

DEH(digital electro hydraulic)

Inlet steam flow governing type Nozzle+throttle

Rated exhaust pressure 0.09 kg/sq.cm

Type of bearing turbine 6 journal +1 thrust

Turbine allowable frequency 47.5 to 51.5 Hz

Turning gear rotation speed 1.5 r.p.m

Ist critical speed of HP & LP rotor 1722 r.p.m

Ist critical speed of LP-A rotor 1839 r.p.m

Ist critical speed of LP-b rotor 1903 r.p.m

Heat regenerative extraction system 3HP htr+1 deaerator+4 LP htr

Final feed water temperature 274.9 deg.cel

Maximum bearing vibration 0.076 m

Maximum allowable exhaust temp. 80 deg.cel.

Coolling water design flow at condenser 70200 TPH

3.3 GENERATOR

[26]

Generator is the important part of thermal power plant.It is device which convert the

mechanical energy into electrical energy.Generator is driven by coupled steam turbine at

a speed of 3000 r.p.m.Due to rotation at high speed it get heat.So there is cooling

construction enclosing the winding core of the genetator.So that during the operation is

being in normal temperature.

In KaTPP , 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).

Fig 3.3 – Generator

GENERATOR SPECIFICATION FOR UNIT I AND II:-

[27]

TABLE – 3.3:Generator Specification

Make CQ GEARBOX China

Type QFSN

Apparent output 706 MVA

Active output 600 MW

Power factor 0.85 lagging

Rated voltage 22 KV

Rated current 18525 Amp

Rated speed 3000 r.p.m

Frequency 50 Hz

Phase connections Double gen.star

Cooling mode H20-H2-H2

Rated H2 pressure 4.5 Kg/sq-cm

Terminal in generator 6

DIESEL GENERATOR SET

It is used to emergency porpuse to supply auxillary system of power plant.3 Set Diesel

generator are use in which one is standby. parameters of generator are as

Table-3.3:Diesel Generator Specification

Make BY STAMFOARD MAHARASTRA INDIA

Rating 1900 KVA

Speed 1500 R.P.M

Rated Current 2643.37 A

Rated Temp 40 Degcel

AMPS 3.6 A

3.4 CONDENSER

[28]

In condenser, the water passes through various tubes and steam passes through a chamber

containing a large number of water tubes (about 20000).

The steam gets converted into water droplets,when steam comes in contact with

water tubes. The condensate is used again in boiler as it is dematerialized water and 5-6

heats the water, which was in tubes, during the process of condensation. This water is

sent to cooling tower.

Condenser is installed below the LP exhaust. The condenser is of surface type

made of fabricated construction in single shell. The tube is of divided type double pass

arrangement, having two independent cooling water inlet, outlet and reverse and water

boxes. This arrangement facilitates the operation of one half of condenser when the other

half is under maintenance. The condenser is provided with integral air-cooling zone at

the centre from where air and non-condensable gases are continuously drawn out with the

help of mechanical vacuum pump.

Area of condenser = 9655 sq m

Cooling water flow rate = 2400 cubic m/Hr.

3.5 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.

[29]

In KaTPP two natural draught cooling towers (2 NDCT) is present with height 202 m

each for each unit.

It is a structure of height 202 m (tallest in the world) designed to cool the water(coming

from condenser) by natural draught. The cross sectional area is less at the centre just to

create low pressure so that ate air can lift up due to natural draught and can carry heat

from spherical drops. The upper portion is also diverging for increasing the efficiency of

cooling tower. Hence it is named as natural draught cooling tower.

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

reckarcolmns. This r.c.c. shell 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 colomnspoud floors that will

generate cascading effect for cooling. The cooling tower shell be capable of cooling the

rated quality of water

Fig 3.5-Cooling Tower

[30]

3.6 WATER TREATMENT PLANT

As everyone know that the cost of any thermal power plant is cores of rupees.So major

problem of any thermal power plant is that how to prevent the corrosion. The water

available can’t 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

Water used in thermal power plant is called ‘Dematerialized Water’ or DM Water.

The treated water is called ‘Dematerialized Water’. The treatment process can be divided

in two sections:

1. Pre-treatment section.

2. Demineralization 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 clariflocculator. The clarified water is

then stored in clarified water storage tanks.

DEMINERALISATION SECTION The clarified water now goes to FCA

(activated carbon filter) where it de-chlorinated. Water then passes through cation

exchanger where weak and strong acidic cations are removed on adding resin.

Water Treatment Stage:-

River (raw water) → Clarification → Filtration → Demineralization

CLARIFICATION AND FILTERATION OF WATER:-

[31]

River water contains different impurities i.e.

Suspended impurities

Biological impurities

Soluble impurities

Colloidal impurities

WORKING:- The raw water enters through valve and than 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 require large tank. In order to cope up the limitation

CLARRIFOCCULATION TANK is used.

This flocculation tank is consist of

1. Clarification zone

2. Flocculationzon

Clarrifocculation tank has a central pillar which has four windows at 90 degree.

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 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.

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

[32]

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 degassifier unit where free CO2 is scrubbed out of water

by upward counter flow of low pressure air flow through degassifier lower and degassed

water is pumped to strong base exchanger(anion–exchanger).

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.

CHAPTER 4

ESP AND AHP SYSTEM

[33]

4.1 ELECTROSTATIC PRECIPITATOR (ESP):

Electrostatic Precipitator (ESP) is equipment, which utilizes an intense electric force to

separate the suspended particle from the gases. In India coal is widely used to generate

power. The exhaust gases are emitted directly into the atmosphere, it will cause great

environmental problems. So it is necessary to extract this dust and smoke before emitted

the exhaust gases into atmosphere. There are various methods of extracting dust but

electrostatic precipitator is the most widely used. It involves electric changing of

suspended particle, collection of charge particles and removal of charge particles from

collecting electrode. Its various other advantages are as follows:

It has high efficiency i.e. about 99%

Ability to treat large volume of gases at high temperature

Ability to cope with the corrosive atmosphere.

It offers low resistance to the flow of gases.

It requires less maintenance.

WORKING PRINCIPLE- The electrostatic precipitator utilizes electrostatic forces to

separate dust particles from the gases to be cleaned. The gas is passed through a chamber,

which contains steel plates (vertical) curtains. Theses steel curtains divide the chamber

into number of parallel paths. The framework is held in place by four insulators, which

insulate it electrically from all parts , which are grounded. A high voltage direct current is

connected between the framework and the ground, thereby creating strong electric field

between the wires in the framework curtains.

Strong electric field develops near the surface of the wire creates Corona

Discharge along the wire.Thus ionized gas produces +ve and –ve ions. In the chamber

plates are positively charged whereas the wire is negatively charged. Positive ions are

attracted towards the wire whereas the negative ions are attracted towards the plates. On

their way towards the curtains negative ions strike the dust particle and make them

negatively charged. Thus is collected on the steel curtains.

The whole process is divided into the following parts:

Corona Generation

Particle Charging

[34]

Particle Collection

Particle Removal

Details of the following are given below-

Corona Generation- Corona is a gas discharge phenomenon associated with the

ionization of gas molecules by electron collision in regions of high electric field

strength. This process requires non-uniform electric field, which is obtained by

the use of small diameter wire as one electrode and a plate or cylinder as the other

electrode. The corona process is initiated by the presence of electron in strong

electric field near the wire. In this region of corona discharge, there are free

electrons and positive ions . Both positive and negative coronas are used in

industrial gas cleaning.

In case of negative corona, positive ions generated are attracted towards the

negative electrode or wire electrons towards collecting plates. On impact of

negative and serve as principle means of charging dust.

Particle Charging- These are two physical mechanisms by which gas ions

impact charge to dust particles in the ESP. Particles in an electric fields causes

localized distortion in an electric filed so that electric field lines intersect with the

particles of maximum voltage gradient, which is along electric field lines. Thus

ions will be intercepted by the dust particles resulting in a net charge flow to the

dust particles. The ions will be held to the dust particles by an induced image

charge force between the ion and dust particle and become charged to a value

sufficient to divert the electric field lines from particles such that they do not

intercept.

Particle Collection- The forces acting on the charged particles are Gravitational,

Inertial, Electrostatic and Aerodynamically. The flow of gas stream is turbulent

flow because it causes the particles to flow in random path through ESP. Particles

will be collected at boundary layers of collector pates. But if flow is laminar,

charge will act on particles in the direction of collecting electrode. This force is

opposite to viscous drag force and thus in the short time, particle would achieve

Terminal (Migration) velocity at which electrical; and viscous forces are equal.

[35]

Thus the flow of the charged particle is decided by the vector sum of these forces

i.e. Turbulent.

Particle Removal- In dry removal of dust collected on plates, Rapping

Mechanism is used. It consider of a geared motor, Which moves along shaft

paced near the support collector electrode and is provided with cylindrical

hammer. On rotating of shaft these hammers strikes the supports causes plate to

vibrates and dust is removed from plates. Removed dust is collected in the

Hoppers below the precipitator. At the time of starting of precipitation of dust

from flue gases, the hoppers are at normal temperature but the ash collected is

very hot. So there is a chance of ash deposit at the exit of the hopper thus causing

problem of removing the ash. To avoid this , heater are provide which increase

the temperature at the exit point o the hopper thus avoiding any undue

accumulation of ash at starting . In other method, the water is allowed to flow

down the collector electrode and hence dust is collected in hoppers below.

GENERAL DESCRIPTION-

The whole ESP is divided into two parts-

Mechanical System

Electrical System

Here we will discuss only Mechanical System (i.e. Precipitator Casing, Emitting and

Collecting System and Hopper).

Precipitator Casing-Precipitator Casing is made of 6mm mild steel plates with

required stiffness. The precipitator casing is all welded construction comprising

of pre-fabricated walls and proof-panels. The roof carries the precipitator

internals, insulator housing, transformer etc. Both emitting and collecting systems

are hung from the top of the casing.

Emitting and Collecting System- Emitting System is the most important part of

ESP. Emitting system consists of rigid emitting frame suspended from four points

on the top of rigid emitting electrodes in the form of open spiral. The four

suspension points are supported on support insulators to give electrical insulation

[36]

to the emitting frame. The frame is designed to take up the retention forces of the

emitting electrode. The emitting electrode consists of hard drawn spiral wires and

are fastened with hooks to the discharge frame.

Collecting system mainly consists of collecting suspension frame, collection

electrodes and shock bars. Collecting electrode are made of 1.6 mm thick Mild

Steel sheets formed in ‘G’ Profile of 400mm width. Hook and guide are welded

on one end and shock iron on the dipped in rust preventive oil tank. Collecting

electrodes bundles are properly bundled in order to avoid any damage to

electrode.

Hoppers- Hoppers are seized to hold the ash for 8-hour collection and is provided

under the casing of ESP. It is of Pyramidal Shape and is 56 in number. It is

preferred to evacuate the hoppers at the earliest as long storage of dust in hopper

leads to clogging of hopper. Also at the bottom of hopper electrical heating is

provided to avoid any condensation, which could also lead to clogging of hopper.

Baffle plates are provided in each hopper to avoid gas leakage.

RAPPING MECAHISM FOR COLLECTING SYSTEM- During electrostatic

precipitation a fraction of dust will be collected on the discharge on the discharge

electrodes and the corona will be suppressed as the dust layer grows. So rapping is done

in order to remove this dust by hammering the electrodes. As the shaft rotates the

hammer tumbles on to the shock bar that transmits the blow to the electrode. The whole

rapping mechanism is mounted on a single shaft, which is collection of ash on the

collecting electrode.

[37]

Fig 4.1 -Electrostatic Precipitation Unit

4.2 ASH HANDLING PLANT (AHP)

The ash produced on the combustion of coal is collected by ESP. This ash is now

required to disposed off. This purpose of ash disposal is solved by Ash Handling Plant

(AHP). There are basically two types of ash handling process 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 system-

Bottom Ash System

Ash Water System

[38]

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.

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.

Fig 4.2 –fly ash system

[39]

CHAPTER-5

CONTROLLING, SWITCHING AND TRANSMISSION

5.1 CONTROL AND INSTRUMENTATION SYSTEM

5.1.1 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

The main components of indoor switchgear are given below:-

1) Bus-Bars

2) Isolating Switches

3) Current Transformers

4) Potential Transformers

5) Circuit Breaker

6) Earthing arrangement

7) Relays

8) 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

[40]

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 tension3.415V 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 & there

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.

(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 on line 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.

[41]

5.1.2 PROTECTION

The fault, which may occur in stator winding are-

a. Phase to phase fault.

b. Phase to ground fault.

c. Line to line fault.

d. 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.

D.C. PROTECTION AND THE COMMON BUS:-

Protection device 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.

[42]

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.

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.

[43]

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.

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.

5.2 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.

CONTROL ROOM PANELS:-

FAN CONTROL DESK: -

1. ID Fan (Induced draft fan, 2nos.) at full load.

2. FD Fan (Forced draft fan, 2nos.)at full load.

3. PA Fan (Primary air fan, 2 nos.) at full load.

[44]

PRESSURE CONTROL DESK: -

1. Furnace pressure (5-10mmwcl.).

2. Primary air header pressure (750-800mmwcl).

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.

TURBINE DESK:- Pressure control, load mode control. Speed control. Ejector, control

valves, stops valves and deviators.

GENERATOR CONTROL PANEL:-Voltage, current, MVAR. Stator, rotor

temperature. For stator cooling.

5.3AUXILIARY 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.

[45]

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 change over of source of

supply from unit station in the case of unit trip out.

The station is having the following auxiliary system: -

a) More then 1500KW connected on 11KV.

b) More then 200KW less then 1500KW connected on 3.3KV.

c) Less then 200KW on 415V.

220V D.C. underground system for use in control and protection system.

3.3 KV SYSTEM: -

For the running unit, the unit auxiliaries are normally fed from gen’r 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.

415 KV SYSTEMS: -

For driving ten 100W motors and other accessories, we need 415V supply. For this

purpose various transformer are 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.

Fig 5.3- Switching and transmission

[46]

5.4 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 different 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 is 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 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 transformer

can be fed from any two buses. Each of these line feeders has been provided with by

pass 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 out

going line are as below:-

1) 400KV TO BTAWDA

2) 400KV TO BTAWDA

3) 220KV TO JHALAWAR

4) 220KV TO JHALAWAR

[47]

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.

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): 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.

[48]

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.)

Inter connected transformer (ICT)

CIRCUIT BREAKER:-

It is an automatic controlling switch used in power house, 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

impulsethrough 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 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.

[49]

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.

Interlock Scheme of Circuit Breaker: -

Generator Breaker

Station Transformer Breaker

Line Feeder Breaker

Bus Coupler Breaker.

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.

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.

[50]

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:-

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 carrier 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.

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.

[51]

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).

CAPACITOR VOLTAGE TRANSFORMER(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.

INTER CONNECTED TRANSFORMER (ICT):-

Purpose of ICT is simply interconnection between 400KV and 220KV Switchyard.

3xM1802-300/D-10.19.300MA2 Type autotransformer is used. manufacture by

CROMPTON GEARVES TRANSFORMER DIVISION BHOPAL

SURGE ARRESTER

The electricity is usually produced in the stator winding of the large modern generators at

about 25,000 volts and is fed through terminal connections to one side of a generator

transformer that steps up the voltage 132000, 220000 or 400000 volts. From here

conductors carry it to a series of three switches comprising an isolator, a circuit breaker

and another isolator.

[52]

The circuit breaker, which is a heavy-duty switch capable of operating in a fraction of a

second, is used to switch off the current flowing to the transmission lines. Once the

current has been interrupted the isolators can be opened. These isolate the circuit breaker

from all outside electrical sources.

Fig-5.4 : Overview of switchyard

From the circuit breaker the current is taken to the bus bars-conductors, which run the

length of the switching compound and then to another circuit breaker with its associated

isolates before feeding to the grid.

Three wires are used in a ‘three=phase’ system for large power transmission. The

centre of the power station is the control room. Here engineers monitor the output of

electricity, supervising and controlling the operation of the generation plant and high

voltage switch gear and directing power to the grid system as required.

[53]

CHAPTER-6

EFFICIENCY

6.1 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.

Efficiency in the case of electrical generator process can be expressed as the amount of

heat energy librated in the boiler compared with the amount of electrical energy

generated with it.

Efficiency is defined as the ratio of output to input. Efficiency of any thermal power

plant can be divided into four parts-

1) Cycle Efficiency

2) Boiler Efficiency

3) Generator Efficiency

4) Turbine Efficiency

Efficiency of thermal power plant is defined as in the term of overall efficiency

i.e. overall efficiency = cycle x boiler x generator x turbine efficiency

CYCLE EFFICIENCY- Cycle efficiency is defined as the ration of energy available for

conversion in work to the heat supplied to the boiler.

BOILER EFFICIENCY- Efficiency of boiler depends upon the following factors:

a) Dry flue gas loss: Increase by excess air in boiler.

b) Wet flue gas loss: Moisture in coal.

c) Moisture in combustion loss: Hydrogen loss.

GENERATOR EFFICIENCY- Efficiency of generator is about 98% also its efficiency

depends upon Copper iron loss and Windage losses

TURBINE EFFICIENCY- It means the efficiency of steam turbine in converting the

heat energy made available in the cycle into actual mechanical work.

[54]

CONCLUSION

Electricity is one of the most vital infrastructure inputs for economic development of a

country. The demand of electricity in India is enormous and is growing steadily. The vast

Indian electricity market, today offers one of the highest growth opportunities for private

developers

This is my first practical training in which I learned lot of things and seen lot of huge

machine like Turbine, Boiler, Generator, cooling tower and many other things.

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 and management.

I think training has essential for any student. It has allowed an opportunity to get

an exposure of the practical implementation to theoretical fundamentals.

[55]

APPENDIX

a) R.V.U.N.L –Rajasthan Vidyut Uttpadan Nigam Limited.

b) C.H.P.- Coal Handling Plant.

c) A.H.P.- Ash Handling Plant.d) D.G.- Diesel Generator

e) B.A.H.-Bottom ash hopper

f) L.P.T.- Low pressure  turbine

g) H.P.T.- High pressure  turbine

h) I.P.T.- Intermediate pressure steam turbine

i) F.D.F.-Forced draught fan

j) I.D.F.-Induced draught fan

k) F.W.H. -Feedwater heater

[56]

REFERENCE

[1]http://www.steelguru.com/indian_news/

First_unit_of_coal_based_Kalisindh_thermal_power_plant_has_commenced_gen

eration/335431.h

               [2] http://www.rvunl.com/Kalisindh%20Thermal%20Power%20Project.php

[3 ]   www.energyindia.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-500-001.

[9] Annual Report o f TCE Ltd.

[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] Generation of electrical power By B. R. Gupta, S CHAND PUBLICATION

[14] Steam and Gas Turbine By R. Yadav , CPH

[15] Engineering Thermodynamics By P. K. Nag, TMH.

[16]   http://rvunl.com/Kalisindh%20Thermal%20Power%20Project.php

[17] http://www.business-standard.com/article/pti-stories/kalisindh-thermal-

power-plant-starts-power-generation-114032200454_1.html.

[57]