training report on cspgcl korba

1. CHHATISHGARH STATE POWER GENERATION
COMPANY LTD.
CSPGCL KORBA (WEST)
A VOCATIONAL TRAINING PROJECT
ON
THERMAL POWER PLANT
(FROM-03/07/2017 TO 02/08/2017)
ON
HASDEV THERMAL POWER STATION
KORBA (WEST)
GUIDED BY : SUBMITTED BY:
MR. V.K PANDEY(E.E) SUDHEER GUPTA
MR. P.K SINGH (A.E.) S/O-RAM AWADHESH GUPTA
MR. EKBAL AHMED(P.S-) BRANCH-ELECTRICAL SEMESTER4th
MR ARJUN PRASAD BAGHEL COLLEGE-GOVT.POLY.AMBIKAPUR
SPECIAL THANKS TO:
MR.N.M.K.NADIG (E.D. GENERATION)
MR. B.M. GUPTA (E.E. TRAINING)

2. ACKNOWLEDGEMENT
It’s our privilege to acknowledge all the technical staffs who us and gave their
moral support to make us understand and complete vocational training.
I express sincere gratitude to:-
MR. V.K.PANDEY (E.E) CSPGCL, KORBA WEST.
MR. P.K. SINGH(A.E.) CSPGCL, KORBA WEST.
MR EKBAL AHEMD (P.S-) CSPGCL, KORBA WEST.
MR ARJUN PRASAD BAGHEL CSPGCL, KORBA WEST.
Special thanks to:-
MR. N.M.K NADIG (E.D.) GENERATION
MR. B.M GUPTA (E.E) TRAINING
SUBMITTED BY:-
SUDHEER GUPTA
BRANCH- ELECTRICAL
SEMESTER-4th
COLLEGE- GOVT POLY. AMBIKAPUR

3. INDEX
 INTRODUCTION OF CSEB WEST
 OPERATION OF PLANT
 BOILER & ITS AUXILAIRIES
 COAL FIRING SYSTEM
 SUPERHEATER & REHEATER
 E.S.P(ELECTRO STATIC PRECIPITATOR)
 TURBINE & ITS AUXILAIRIES
 GENERATOR & ITS AUXILAIRIES
 CONTROL & INSTRUMENTATION
 SWITCH YARD

4. INTRODUCTION OF CSEB WEST

5. INTRODUCTION:-
Basically Korba is considered as back bone of power generation individually
Korba generated about 4530 mega watt of energy. Four plant are stabilized has
one of Govt. of India enterprise known as national thermal power corporation
(NTPC) capacity 2630 mega watt situated in Korba (West) and other of 440
mega watt and 500 mega watt situated in Korba (East ). Private sector “sterite”
is also running. Another Hydel Electrical project at Bango of 120 mega watt
considering the success of all this project CSPGCL is planned established two
unit of 500 mega watt at Korba (West) as well as Korba (East) coal needed to
all the plant are supplied through south eastern coal field limited.(SECL).
Since we visited HTPS. We will discus it in detail. HTPS consist of 4X210 mega
watt units. First two units are made up of combustion engine boiler and BHEL
make turbine where are as phase two i.e. unit no.3 and 4 made up ABL boiler
and BHEL made turbine boiler or unit no.1 and 2 natural circulation reheat.
Regenerate type boiler its operation drum pressure is 167 kg/cm2
, 680 T/hr flow
turbine is of cylinder multistage double flow turbine.
Boiler of unit 3 and 4 is superheat regenerated type natural circulation front
fired ABL boiler it’s turbine is some as unit 1 and 2. The main difference
between ABL and BHEL boiler is that BHEL boiler is corner fired while ABL
boiler is front fired boiler.

6. OPERATION OF PLANT

7. COAL HANDLING PLANT:-
This is an indispensable part of the power. The coal handling plant is basically a
unit which handles the coal that is it transports coal from the reserves to the
place of their requirement and also maintains an extra stock of coal at a place
near by the power plant for any emergency.
The coal handling plant is divided into two main parts:-
1. Coal Handling Plant External.
2. Coal Handling Plant Internal.
The coal is transferred using conveyer belts which are driver by motor
controlled rollers and supported by idler rollers. There are many belts which are
inter connected to each other at different stations and take the coal to different
directions, that is either directly to the power plant for use or for storing in the
different storage yards present near the factory site. The basic figure of the belt
can be presented by the following line diagram.
The convyere belt, along its length has one head which is driven by a motor and
a tail end which is supported by an idler .
The belt in the course of its journey is supported by many rollers sets in
between. There are some special idle rollers called self aligning idlers . These
align the belt and thus stop it from sliding of the rollers. There are also some
rubber rollers which are used to absorb shock at the points on the belt where
coal falls with an impact so that the belt does not snap.

8. There is a take up roller arrangement below the belt as shown in the diagram.
This is used to control the tightness of the belt. This is needed because in
summer the belt tends to length on and in winter it tends to shorten thus to
maintain a proper fit it is necessary to move this down or up as per our
requirement. There are snub rollers near the head and tail end which are used to
increase the surface area of content.
The block diagram of the mechanism that provides power to the head is as
follows:-
First power from the motor is transferred from to the resilient plant (which used
to bear start up shocks) from which is transferred to the fluid coupling. Next the
power is transferred to the gear coupling which finally transfers power to the
head end.
As the coal is transferred from one belt to another it is done so with the help of
‘Hoppers’. Also every hoppers opens to two belts from which supply is
controlled to one belt using motor operated ‘Flap Gates’ which are contolled by
actuated motors. One belt will always be in use and one will be a spare for
emergency purpose. The coal is finally sent to the raw coal bunkers of the
respective mills.

9. ELECTRICTY PRODUCED INPLANT

11. BOILER & ITS AUXILIARIES

12. INTRODUCTION:-
A steam generator or boiler is a closed vessel made of steel. Its function is to
transfer the heat produced by the combustions of fuel (solid, liquid or gaseous )
to water and ultimately to generate steam.
The boilers of units one and two are supplied by BHEL (Bhopal). The
circulation, water tube, reheat, regenerative type boiler and has a rotary air
heater. It is a two pass boiler with fourteen headers in all.
Boiler of unit three and four are supplied by ABL, which is now called as
ABBL.
Some of main differences between the two type of boilers are stated below:-
1.BHEL BOILER:-
 It is a corner fired , pulverized coal , natural circulation, and water tube
,reheat, regenerative type boiler.
 It is present in units one and two.
 It has four coal firing tubes at each, corner at six elevations each, thus a
total of twenty four.
 It has rotating air heater. This makes it more efficient and gives it a
longer life time as compared to ABL boiler.
 The mills supplying pulverized coal are six in and bowl mills.
 They have got igniters.
2.ABL BOILER:-
 It is also of natural circulation, pulverized coal, water tube boiler the
main difference being in that fact that it is a front and rear end boiler.
 It is present in unit three and four.
 It has twelve coal firing tubes at the front end and twelve at the rear thus
a total of twenty four
 It has a fixed air heater thus giving it less efficiency as compared to
BHEL boiler.
 The coal is supplied by ball and race mills which are six in number.
 They don’t have igniters.
As mentioned above the BHEL boiler is a corner fired pulverized coal natural
circulation water tube, reheat , regenerative type boiler and has a rotary air
heater. It is a two pass boiler with fourteen headers in all.

14. COAL FIRING SYSTEM:-
These nozzle can be tilted to an angle of up to 300
as per requirement. Also for
the optimum firing of the boiler we use the help of the combustion triangle
which is made with the help of three parameters namely temperature, time and
turbulence.
The boiler is mainly divided into thirteen division as shown in the below.

15. The levels A,B,C,D,E and F are the levels at which coal is fired into the boiler.
The levels AB,CD and EF are the levels where oil is fired into the boiler and the
remaining four levels are used for sending the air into the boiler which is used
for secondry combustion.
SOME PARAMETERS:-
Drum design pressure : 173.8kg/cm2
Drum operating pressure: 157.74kg/cm2
Maximum continuous Evaporation: 680T/hr
Supporting Structure:-
It is a collection of systematically arranged columns stiffened with horizontal
beams used to support the boiler drum, super heater, reheater, economiser, air
preheater, burners etc.
Boiler Drum:-
The main function of the boiler drum is to separate the steam from the water. It
is located at the upper front of boiler.
Economiser:-
An economiser is a device used to heat feed water by utilizing the heat from the
exhaust flue gases before leaving through the chimney. As the name indicates
the economiser improves the economy of the boiler.

16. SUPER HEATER:-
A super heater is a device used to increase the temperature of the saturated
steam without raising its temperature. The steam first passes through the
primary super heater and then through the pendent super heater and finally
through the final super heater.
REHEATER:-
It is used to reheat the steam after it comes out from the high pressure turbine
and before it is sent to the intermediate pressure that is to a temperature of
5400
c.
Rotary Air Preheater:-
It is used to heat that the air before it enters the mills and the boiler in case of
the Primary Air Fan(PA FAN) and the forced draught fan respectively. It is
rotary type and can be represented as follows on the next page.
It contains buckets which are named so because of their bucket like structure.
These are heated by the hot flue gases in the chamber in which hot flue gases
pass thus collecting heat from the gases. These buckets in the process of heating
pass to the area in which the air for primary air id flowing through and hence
pass on some heat to them and then pass on to them and then pass on to the
region where there is air for the forced draught and give some heat to them.
Then they return to the initial position tube heated again.

17. Coal bunkers:-
These are in process storage silos used for storing crushed coal from the coal
handling system. There are six such bunkers supplying coal to the
corresponding mills. These are located on the top of the mills so is to aid in
gravity feeding of coal.
Coal feeders:-
Each mills is provided with a coal feeders to transport raw coal to the inlet
leading to mill at a desired rate.
PRIMARY AIR FAN:-
They are used to handle atmospheric air and heat it before sending it to the
mill.Theyare of
Capacity : 170.5m3
/Sec
Total Head : 1183mm WCI
Speed : 1480RPM
Motor Rating : 6.6KV
Lubrication : Motor(grease), Fan (oil)
Control : Blade Pitch

18. MILLS:-
Capacity : 66.3T/hr
PulvSpeed : 600 RPM
Power : 525 KW
Rolls : 3 Nos

19. INDUCED DRAFT FAN(ID FAN):-
1.Double suction, single discharge
2. Inlet guide vane and hydraulic scoop control
3. 6.6 KV motor and having

20. FORCE DRAFT FAN(FD FAN):-
Capacity : 246m3
/Sec
Total Head : 351mm WCI
Speed : 6.6 KV
Motor rating : 6.6 KV
Lubrication : motor(grease), Fan(oil)
Control : Blade Pitch

21. ELECTROSTATIC PRECIPITATOR:-
It precipitates (collects) the dust particles from the flue gases by means of
electrical power. It essentially consist of 2 set of electrodes which are
completely insulated from each other and a high voltage electrostatic field
maintained across them.

23. BOILER AIR &FLUE GAS PATH :-
FLUE GAS SYSTEM:-
The flue gas draft plant draws hot flue gases from the furnance and discharges
them to atmosphere through the chimney. During its passages to the chimney,
flue gas is passed through an economiser and 4 air preheater to improves the
thermal efficiency, and through four electrostatic precipitator to keep dust
emission from the chimney within the prescribed limits. The flue gas ducting
starts from boiler down stream of the economiser and directs flow towards three
primary and secondry air heaters. The primary and secondryair preheaters gas
inlet duct is fitted with biplane isolating dampers. The outlet ducts of
corresponding primary and secondry air heaters combine then discharge
through a regulating damper into the electrostatic precipitator common inlet
duct which directs flue gas through 4 electrostatic precipitator into ID FAN
common inlet duct. The inlet outlet ductes of each precipitator have motor
operated guillotine gates.

25. TURBINE & ITS AUXILIARIES

26. INTRODUCTION:-
A turbine is a prime mover in a which rotor motion is obtained by the gradual
change of the momentum of the steam. The force exerted on the blades is due to
the velocity of steam. This is due to the fact the curved blades by changing the
direction of steam receive a force or impulse. Thus the pressure of steam rotates
the wheel carrying values or blades directly. The turbine blades are curved I
such a way that the steam directed upon them outer’s without shock, though
there is always some less of energy due to friction upon the surface of blades.
All the turbines of all four units are supplied by BHEL Bhopal. The turbines are
mainly classify into three parts:-
1. High pressure turbine(HTP)
2. Intermediate pressure turbine(IPT)
3. Low pressure turbine(LPT)
Turbine parameters:-
1. Rated RPM -3000
2. Rated pressure(kg/cm2
)
Initial steam -152
Hp Exhaust-40.5
Ip inlet- 35.25
Lp Exhaust-0.126
3. Temperature(0
c)
Inlet steam- 535
Ip Exhaust- 535
Hp Exhaust- 343
Lp Exhaust- 49
AUXILIARIES:-
 Turbine lube oil system for bag lubrication
 Turbine control oil system for turbine governing
 Condenser for condensing the steam
 Deareator for removing oxygen from condensate
 Boiler feed pumps for pressurizing the water
 Feed heaters for improving cycle efficiency

27. WORKING PRINCIPLE:-
 Steam turbine depends upon dynamic action of steam
 According to Newton’s second law of motion, the force is proportional
to the rate of change of momentum.
 If a high velocity steam is allowed to pass through curved blades it will
impart force to blades & the blades will move in the direction of force.
TYPES OF TURBINE:-
1.HIGH PRESSURE TURBINE:-
2.INTERMEDIATE PRESSURE:-

28. LOW PRESSURE TURBINE:-
TURBINE GOVERNING SYSTEM:-
To govern means to control & regulate certain parameters to achieve expected
results.
Turbine governing system is meant for regulation of turbine speed under no
load & varying load condition.
It helps in precise control of grid under normal operation & protects machine as
well as grid during emergency situation.
TURBINE PROTECTION SYSTEM:-
Turbine protection system perform to cover the following functions:-
 Protection of the turbine from inadmissible operating conditions.
 In case of plant failures to maintain to a minimum.
The standard turbine protection consist of :-
 Mechanical hydraulic turbine.
 Electrical turbine protection.

29. GENERATOR & ITS
AUXILIARIES

30. INTRODUCTION:-
The device which converts mechanical energy of turbine into electrical energy.
The steam turbine & alternator are directly coupled to avoid transmission losses.
Turbo-alternator is high speed machine (3000) rpm for 50Hz system. The
210MW generator is a 3-phase, horizontally mounted two pole cylindrical rotor
type, synchronous machine driven by steam turbine. The stator winding is
cooled by dematerialized water flowing through the hollow conductor while the
rotor winding cooled by hydrogen gas maintained inside the machine is
provided with epoxy thermo-setting type insulation. The machine is provided
with completely static thyristor controlled excitation system, fed from terminals
of the machine.
Four hydrogen coolers are provided to cool the hot gas maintain the cold gas
temperature at 400
c .liquid level detector(LLDs) are provided to indicate liquid
in generator casing. This provision is to indicate leakage of oil or water inside
the generator. It can be drained through drain valve. 112 gas purity to be
maintained of very high order i.e. more than 97%.
GENERATOR WORKING PRINCIPLE:-
 A.C generator is based upon the principle of electromagnetic induction.
 E.M.F generated, e=4.44 o f n volts.
 f =frequency of cycle per second =pn/120

32. SWITCH YARD

33. 400 KV SWITCH YARD:-
Here is the Hasdev Thermal Power Station. There are two switchyard, first
220KV switchyard and second 400KV switchyard. In this report we explain
400KV switchyard.
As it names reflect where are switch or control incoming and outgoing feeder
called switchyard and 400KV. As we know transmitting electrical power at high
voltage has very advantageous. 400KV switchyard are generally used in India’s
but recently 765KV switchyard also comes in operation.
In HTPS 400KV switchyard there are 8 Bays are available but only seven bays
are in use and one bay is in spare. Bhilai feeder and NTPC feeder are main
feeder in 400KV switchyard. Also here a interconnecting transformer is
installed between 220KV switchyard and 400KV switchyard.
In 400KV switchyard double bus with transfer bus is used. In this arrangement
for two bus, one reserve bus is available thus its provides facilities for both
breaker and bus maintainance.
Bay No-1:-
In bay no-1 bus is connected to generator transformer of unit 3. At unit 3
generating voltage is 15.75 KV, which is stepped up to 400KV with the help of
generating transformer no 3.

34. Generating transformer unit no-3 rating:-
Manufacturer – BHEL
MVA – OFAF ONAF ONAN
250 150 100
Volt - 420/15.75KV
Current – 343.87/9184.29 Amp.
Phase – Three
Bay- No 2:-
In bay no-2 autotransformer with 33KV tertiary winding connected which
connects 220KV switchyard with 400KV switchyard so it is called
Interconnecting transformer. Interconnecting transformer s are single phase
transformer that is one transformer for each phase, so three transformers with a
spare transformer, therefore total four transformers are installed. Also 33KV
tertiary winding is giving which may used for lighting purpose but here it is
connected to delta and earthed to ground.
Inter connecting transfer rating:-
Volt - 400KV/200KV/33KV
MVA- OFAF ONAF ONAN
88.7 700 166.7
Maximum temperature rise:-
Oil - 500
c 500
c500
c
Winding - 550
c 550
c550
c
Line current in ampere:-
HV-IV - 280.8 433 721.8
IV - 525.1 787.8 1312.4
LV - 578.8 1015.2 1892.2

35. Impedence voltage:-
HV-IV - 12.79%
HV-LV - 43.10%
IV-LV - 28.19%
Lighting impulse insulation level:-
HV - 1300 KVP
IV - 900KVP
LV - 250KVP
Switching HV- 1050KVP
Power frequency:-
HVN - 38KVrms
LVN - 95KVrms
Oil weight - 38280Kg
Total weight- 180500Kg
Bay no-3:-
In bay no3 bus is connected to generating transformer no-4.
At unit no-4 generating voltage is 15.75KV, switch is stepped upto 400 KV
with the help of generating transformer no-4.
Generating transformer unit no-4 ratings:-
Manufacturer - BHEL
MVA - OFAF ONAF ONAN
250 150 100
Volt - 420 / 15.75 KV
Current - 344 / 9164 Amp.
Phase - Three

36. Bay no-4:-
Bay no-4 is in spare and will be commissioned as per requirement in future.
Bay no-5:-
In this bay no-5 Bhilai feeder is situated. The total length of Bhilai feeder is
normally 211.6 kms. It is important feeder at 400KV switchyard. Here MICOM
P442relay is installed for distance protection and as a protection relay is
installed for under voltage and over voltage protection.
Bay no-6:-
Bay no-6 is for bus transfer. Bus transformer is used when we need to take any
one feeder in transfer bus. Transfer bus is charged through that bus from where
feeder us charged to transfer bus.
Bay no-7:-
In bay no-7 NTPC feeder is situated. The total length of NTPC feeder is
6.3kms. MICOM P442 is installed here for distance protection. Here also
switching power blocking relay is installed.
Bay no-8:-
In bay no-8 bus coupler is situated. It is used to connected one bus to motor. It
is required to normalized and maintain the power flow from both of the bus.
220KV SWITCHYARD:-
Switchyard is considered at the heart of the power plant. Power generated can
be worthly only it is successfully transmitted and received by its consumers and
producers. Switchyard plyas an important role as junction between generation
and transmission.
The power generated by the generator is –
:15.75KV(210MW)
:11.00KV(120MW)
Which is then stepped up upto 400KV & 220KV by the generating transformer
and the transmitted is switchyard.
There are several types of switchgears are in used which given is following:-

37.  bus arrangement:-
1. no. transfer bus.
2. no. Main bus.
 Three pantograph isolators
 One center break isolators
 One SF6 ckt breaker
 Current transformer
 Voltage transformer
 Lighting arrestor
 Breaker earth bus side
 Breaker earth line side
 Line earth
Each bay has respective control panel and relay panel in control room.
Wave traps are provided in transmission line teleportation and data.
Various interlocks scheme are provided between isolatorsckt breakers and
earth switch. Protections are also provided for bus bar line etc.
Bus bar:-
In electrical power system a bus bar is a thin strip of copper or aluminium that
conduct and electrically within switchyard distribution board substation or other
electrical apparatus.
The size of bus bar is important to determine the maximum amount of current
that can be safty carried various incoming and outgoing ckt are connected is bus
bar.
Isolators:-
Isolators are primarily of load devices used to isolate equipment and line in
transmission line. They can also disconnect low charging current upto
0.75Amp.
Two types of isolators are used in switchyard :-
a). Centre break type isolators.
b). Pantograph isolators.
SF6 ckt breaker:-
SF6 is an inert heavy gas heaving good dielectric and are extinguishing
properties. The dielectric strength of gas increases with pressure and to more

38. that of 3Kg/cm2
. The gas is transported i liquid from in cylinder. Before filling
gas the CD is evaluated to the pressure of hydrogen, so as to remove the
moisture and air the gas is filled.
Surge / lighting Arrestor:-
Lighting arrestors protect equipement of transmission and distribution system
worth several magnitudes more than the arrestor themselves from the effect of
lighting and switching over voltage. It is a device used to ground without
affecting the continuous supply of water.
The purpose is always to limit the voltage across the terminal of the equipment
to be protected bellow, its insulation withstand voltage. This is achieved by the
connecting elements with an extremely non linear voltage current characteristics
in parallel to the terminal of the equipment so called metal oxide.
Surge arrestor containing ceramic body mainly made from zinc oxide and
bismuth oxide are used now a day. They are connected between phase
conductor and ground.
Current Transformer:-
Current transformer is a device used to scale large primary current to a smaller
easy to measure secondry current like a traditional voltage transformer. The
relationship between input and output current. Current transformers of varios
shape and size are used as an interfacing solution between high current and
instrumentation device.
Voltage transformer:-
Voltage transformers are used for measurement and protection according them
other measuring type or protection type voltage transformer. They may be either
single or three phase unite.
Wave Trap:-
Wave trap is a parallel tuned inductor. Capacitor bank ckt made to be resonant
at the desired communication frequency. It is installed on power line in
substation. Power line corner communication refers to the concept of
transmitting information using the electrical distribution network
communication channel.
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