A presentation on summer vacation training in NTPC

1. STANI MEMORIAL COLLEGE OF
ENGINEERING & TECHNOLOGY
(APPROVED BY AICTE, MINISTRY OF HRD,GOVT. OF INDIA & AFFILIATED TO RTU, KOTA)
PHAGI, JAIPUR -303005
A PRESENTATION OF SUMMER VACATION TRAINING IN “NTPC”
BARH, PATNA
SUBMITED BY - AJEET KUMAR

2. NTPC BARH

3. NTPC OVERVIEW
 NTPC Limited (Formerly National Thermal Power Corporation) is the largest
power generation company in India and was founded on November 7,
1975.
 Contributing 26% of country’s entire power generation, it has placed itself
in the Nav - Ratan companies of Indian government and hence is the
public sector company.
 The total installed capacity of the company is 31134 MW
 NTPC has been operating its plants at high efficiency levels. Although the
company has 18.79% of the total national capacity it contributes 28.60%
of total power generation due to its focus on high efficiency.
 The company has set a future goal of having 75000 MW by 2017.

5. Beneficiary state
The states & UTs of Northern & Western regions and state of Bihar

6.  Coal before fixing in the furnace is
Pulverized.coal pulverization is required in
the whole system process not just in terms of
furnace performance and heat rate but in
terms of mechanical reliability and integrity
of furnace.
 Flame is established in the furnace
Using the LDO(light diesel oil).LDO is
atomized by applying arc to it.
 Coal+air- Co2+CO+Sox+MOx+heat+ASH
Here CO2-heat carrier
CO-Acidic, danger to tubes(less air)
MOX,SOX-Acidic formation in water
bodies and atmosphere.
 To avoid the gases CO,MOX,SOX a ratio is maintained between air and coal of 1:6.It also ensures
proper combustion.The water is purified(DM water) before injunction in the furnace to prevent
choking of pipes due to the scale formation.

7. 1.BOILER
2.TURBINES
3.COOLING WATER PUMP
4.CONDENSER
5.DEAREATOR
6.REHEATER
7.AIR PREHEATER
8.PRECIPITATOR
9.ECONOMISER
10.COOLING TOWER
11.TRANSMISSION LINES(3 PHASE)
12.UNIT TRANSFORMERS(3 PHASE)
13.ELECTRIC GENERATORS(3 PHASE)
14.CONDENSATE EXTRACTION
PUMP
15. Steam governor valve
16. FEED HEATER
17.COAL CONVEYOR
18.COAL HOPPER
19.FORCED DRAUGHT FAN
20.FLUE GAS

8. Boiler is a rectangular furnace about 50 feet on side and 130 feet tall. theirs walls
are made of high pressure steel tubes about 2.3 inches in diameter which circulates
DM water to be converted into steam. The thermal radiation heats water and
changes to steam. Steam is sent to the turbine .The efficiency and technology of
boiler vary according to the operational pressures.
1. Operational pressure>221 KSC---%n=42.45%-----super critical boiler
2. 175KSC <Operational pressure<221 KSC---%n=38.42%----- critical boiler
3. Operational pressure<175KSC---%n=38%-----sub critical boiler
The turbine generator consists of a series of steam turbines interconnected to each
other and generators on a common shaft.
It pumps the water from the cooling tower which goes to the condenser.

9. The steam coming out from the Low Pressure Turbine
(a little above its boiling pump) is brought into thermal
contact with cold water (pumped in from the cooling
tower) in the condenser, where it condenses rapidly
back into water, creating near Vacuum-like conditions
inside the condenser chest.
A deareator is a device for air removal and used to remove
dissolved gases (an alternate would be the use of water
treatment chemicals) from boiler feed water to make it
noncorrosive.

10. Reheater is a heater which is used to raise the
temperature of steam which has fallen from the
intermediate pressure turbine.
The purpose of the air preheater is to recover the heat from
the boiler flue gas which increases the thermal efficiency
of the boiler by reducing the useful heat lost in the flue
gas.
An Electrostatic precipitator (ESP) is a particulate device that
removes particles from a flowing gas (such as air) using the force of
an induced electrostatic charge.

11.  General Voltage Level
LT – 415 V
HT – 11KV & 3.3 KV
EHT – 400KV
 Voltage generation level (NTPC Barh)
stage 1 – 24.5kv
stage 2 – 21.5kv
 voltage level ( power plant)
5.5kv, 11kv, 132kv,400kv

12. Switchyard is considered as the HEART of the Power Plant. Power generated can be worthy only if it is
successfully transmitted and received by its consumers. Switchyard plays a very important role as a junction
between the generation and transmission. It is a junction, which carries the generated power to its destination (i.e.
consumers).
Outdoor equipments
1. Bus bar
2. Lightening Arrester
3. Wavetrap
4. Breaker
5. Capacitive voltage transformer
6. Earthingrod
7. Current transformer
8. Potential transformer
9. Lightening Mask
Indoor equipments
1. Relays
2. Control panels’
3. Circuit breakers

13. 1. Bus bar
In electrical power distribution, a busbar is a strip or
bar of copper, brass or aluminium that conducts electricity
within a switchboard, distribution board, substation,
battery bank, or other electrical apparatus.
PICTORIAL VIEW OF BUS BAR
A lightning arrester is a device used on electrical
power systems and telecommunications systems to
protect the insulation and conductors of the system
from the damaging effects of lightning. The typical
lightning arrester has a high-voltage terminal and a
ground terminal.
2.lightning arrester
PICTORIAL VIEW OF LIGHTNING ARRESTER

14. 3.wave trap
Wave Traps are used at sub-stations using Power Line
Carrier Communication (PLCC). PLCC is used to
transmit communication and control information at a
high frequency over the power lines..
4 .Breaker
A circuit breaker is an automatically operated
electrical switch designed to protect an electrical
circuit from damage caused by overload or short
circuit. Its basic function is to detect a fault condition
and interrupt current flow.

15. Depending on the arc quenching medium being used C.B.s can be categorizedinto various
types. In BSTPP for 400 KV/132 KV switchyard only one type is being used
ACB (Air break circuit breaker):-
operated as well asarc quenched through air.
BOCB (Bulk oil circuit breaker):-
arc quenching done through oil(Aerosol fluid oil).
MOCB (Minimum oil circuit breaker):-
arc quenching done through oil(Aerosol fluid oil).
ABCB (Air Blast Circuit Breaker):-
arc quenching done by blast of air
SF6 circuit breaker:-
arc quenching done through SF6 gas.

16. A capacitor voltage transformer (CVT), or
capacitance-coupled voltage transformer (CCVT), is
a transformer used in power systems to step down
extra high voltage signals and provide a low voltage
signal.
5. CAPACITIVE VOLTAGE TRANSFORMER
6.CURRENT TRANSFORMER
The current transformer is a step up transformer , it
means current is stepped down to a very low value
(generally 1 A or 5 A) so that it can be used for
measuring and protection purposes .

17. Current Transformer is used for basically two major functions: -
1 .Metering
which means current measurement.
2. Protection
such as over current protection, overload earth faultprotection, Bus-bar protection, Bus
differential protection.CT is typically described by its current ratio from primary to secondary.
ISOLATOR
An isolator is one, which can break an electrical circuit when the circuit is to beswitched on
no load. These are normally used in various circuits for the purposes of isolating a certain
portion when required for maintenance etc.

18. In BSTPP there are two switchyards:-
(i) 400KV SWITCHYARD
(ii) 132KV SWITCHYARD
.400 KV SWITCHYARD
There are total 22 bay in 400 KV switchyard. A Bay is basically
a way for the incoming power from generator as well as
outgoing power for distribution.
 5 Bay for each generating transformer
 3 Bay for ICT(Inter Connecting Transformer)
 2 Bay for PATNA line
 2 Bay for KAHALGAON line
 2 Bay for BALIA line
 7 for FUTURE line
 1 Bay for SHUNT REACTOR
There are four main buses in 400 KV switchyard.
 Main bus – 1& 2
 Main bus – 3&4
132 KV SWITCHYARD
There are total 11 Bay in 132 KV switchyard.
 3 Bay for ICT (Inter Connecting Transformer)
 5 Bay for S.T (Station Transformer)
 2 Bay for MST (Miscellaneous Service Transformer)
 1 Bay for Bus Coupler
There are two main buses in 132 KV switchyard.
 Main bus - 1
 Main bus - 2

19. It is a static machine which increases or decreases the AC voltage without changing the frequency of the supply. It is a
device that:
 Transfers electric power from one circuit to another.
 It accomplishes this by electromagnetic induction.
 In this the two electric circuits are in mutual inductive influence of each other.
WORKING PRINCIPLE: It works on FARADAY‟S LAW OF ELECTROMAGNETIC INDUCTION (self or
mutual induction depending on the type of transformer).
CLASSIFICATION:
(I) ACCORDING TO THE CORE: a) Core type transformer b) shell type transformer c) Berry type transformer
(II) ACCORDING TO PHASES: a) 1phase transformer b) 3phase transformer
(III) ACCORDING TO THE PURPOSE FOR WHICH USED : a) Distribution transformer b) Transmission
transformer c) Generator transformer d) Station transformer e) Unit Auxiliary transformer (UAT)

20. GENERATING TRANSFORMER:-
A generating transformer is a single – phase power transformer(3 single phase units shall form a
bank) . Generating Transformer steps–up the generated voltage of 24 KV by alternator to a higher
voltage of 400 KV (hence, working as a step-up Transformer).This voltage of 400 KV is then
transmitted to Switchyard
INTER CONNECTING TRANSFORMER:-
An ICT is a 3-phase auto transformer used to interconnect 400 KV switchyard and 132 KV switchyard
STATION TRANSFORMER:-
Station Transformer is used only for initializing the start-up of the station (Main Plant).It
is very beneficial during emergency situations such as tripping of Units, shut-down etc. Station
transformers is used to start Station auxiliaries a which are required for generating services such as
coal and ash handling system, lighting system, water purifying system etc

21. UNIT TRANSFORMER
The Unit Auxiliary Transformer is the Power Transformer that
provides power to the auxiliary equipment of a power
generating station during its normal operation.
MISCELLANEOUS SERVICE TRANSFORMER
Miscellaneous service transformer are used to supply
miscellaneous loads of plant. It is a two winding
transformer connected to 132 KV switchyard

22. GENERATOR SPECIFICATIONS-
KVA 247000
Pf 0.85
Volts of stator 15750
Amperes of stator 9050
Volts of rotor 310
Amperes of rotor 2600
Rpm 3000
Hz 50
Phase 3
Connection YY
Coolant water(stator)&hydrogen(rotor)
Gas pressure 3.5kg/cm-sq.
Insulation class B
Turbo generators are used in thermal power stations because of the steam energy to mechanical energy
conversion, turbo generators are more efficient.