NTPC Anta Training Report
NTPC Anta Training Report
NTPC Anta Training Report
INTRODUCTION
National Thermal Power Corporation Ltd (NTPC) was incorporated in 1975 by an Act of
parliament, to supplement the efforts of the states for quicker and greater capacity addition
in thermal power generation .In1997 the Department of Public enterprises, Government of
india status with power of operational autonomy to the board of NTPC . This helped NTPC
in speedy implementation of power projects. Recently NTPC has been awarded the
Maharatna status which has given it greater autonomy.
In line with its vision and mission over the last five years NTPC has grown
to become the largest power utility in India with a commission degeneration capacity of
34,754MW (asonJuly,2011) .Besides largest power generation utility NTPC has also grown
to become the number one independent power in Asia and second globally in 2009 (by Platt
a division of McGraw-Hill companies) ,5largest company in Asia and 317Largest company
th
in the world (FORBESranking2009) .NTPC has also thehonor of becoming the 6 largest
the power generator in the world and second most efficient in terms of capacity utilization
among stop 10 utilities in the world.
In line with the changing business environment ,NTPC has expanded its
operation in the area of Hydro Power and cover substantial ground in the area sof Coal and
Mining .Oil& Gas Value chain ,Power Trading and Distribution .With the forward and
th
backward plans ,NTPC has been re-christened as NTPC Limited since 7 Nov2005.
Chapter-2
STATE
COMMIS
SIONEDC
1.
Anta
Rajasthan
413
2.
Auriya
UttarPradesh
652
3.
Kawas
Gujarat
645
4.
Dadri
UttarPradesh
817
5.
Jhanor- Gandhar
Gujarat
648
6.
Rajiv
Kerala
350
7.
GandhiOCP
Fridabad
Haryana
430
Total
3,955
Table 2.1
Gas
Station
3. Steam Turbine
: 1x 153.2MW
4. Total Capacity
: 419.33 MW
5. Gas turbine
6. GT Comprossor
Chapter-3
Chapter-4
GAS TURBINE
Gas turbine is a heat engine working on the air standard Brayton cycle.
The process Includes
1. Compression: Compression of working medium (air) taken from atmosphere in a
compressor.
2. Combustion: Increase of working medium temperature by constant ignition of fuel
in combustion chamber.
3. Expansion: Expansion of the product of combustion in a turbine.
4. Rejection: Rejection of heat in the atmosphere.
Figure4.1GasTurbine
Chapter-5
FIELD INSTRUMENTS
1. PRESSURE GAUGE
2. TEMPERATURE GAUGE
3. PRESSURE TRANSMITTER
4. TEMPERATURE TRANSMITTER
5. DP TRANSMITTER
6. VIBRATION PICK UP
7. SPEED PICK UP
8. FLOW SENSOR
9. LEVEL SENSOR
10. PRESSURE SWITCH
11. THERMOCOUPLE ,RTD
10
11
12
13
5.5 THERMOCOUPLE
It is based on SEEBACK effect which says that when heat is applied to a junction of two
dissimilar metals an EMF is generated which can be measured at the other junction.
14
Chapter-6
GENERATOR
The transformation of mechanical energy into electrical energy is carried out by the
Generator. This Chapter seeks to provide basic understanding about the working principle and
development of Generator.
15
Rotor
The electrical rotor is the most difficult part of the generator to design. It revolves in most
modern generators at a speed of 3,000 revolutions per minute. The problem of guaranteeing
the dynamic strength and operating stability of such a rotor is complicated by the fact that a
massive non-uniform shaft subjected to a multiplicity of differential stresses must operate in
oil lubricated sleeve bearings supported by a structure mounted on foundations all of which
possess complex dynamic be behavior peculiar to them. It is also an electromagnet and to
give it the necessary magnetic strength.
The windings must carry a fairly high current. The passage of the current through the
windings generates heat but the temperature must not be allowed to become so high,
otherwise difficulties will be experienced with insulation. To keep the temperature down, the
cross section of the conductor could not be increased but this would introduce another
problems. In order to make room for the large conductors, body and this would cause
mechanical weakness. The problem is really to get the maximum amount of copper into the
windings without reducing the mechanical strength. With good design and great care in
construction this can be achieved. The rotor is a cast steel ingot, and it is further forged and
machined. Very often a hole is bored through the centre of the rotor axially from one end of
the other for inspection. Slots are then machined for windings and ventilation.
Rotor winding
Silver bearing copper is used for the winding with mica as the insulation between conductors.
A mechanically strong insulator such as micanite is used for lining the slots. Later designs of
windings for large rotor incorporate combination of hollow conductors with slots or holes
arranged to provide for circulation of the cooling gas through the actual conductors. When
rotating at high speed. Centrifugal force tries to lift the windings out of the slots and they are
contained by wedges. The end rings are secured to a turned recess in the rotor body, by
shrinking or screwing and supported at the other end by fittings carried by the rotor body. The
two ends of windings are connected to slip rings, usually made of forged steel, and mounted
on insulated sleeves.
16
Rotor balancing
When completed the rotor must be tested for mechanical balance, which means that a check
is made to see if it will run up to normal speed without vibration. To do this it would have to
be uniform about its central axis and it is most unlikely that this will be so to the degree
necessary for perfect balance. Arrangements are therefore made in all designs to fix
adjustable balance weights around the circumference at each end.
Stator
Stator frame: The stator is the heaviest load to be transported. The major part of this load is
the stator core. This comprises an inner frame and outer frame. The outer frame is a rigid
fabricated structure of welded steel plates, within this shell is a fixed cage of girder built
circular and axial ribs. The ribs divide the yoke in the compartments through which hydrogen
flows into radial ducts in the stator core and circulate through the gas coolers housed in the
frame. The inner cage is usually fixed in to the yoke by an arrangement of springs to dampen
the double frequency vibrations inherent in 2 pole generators. The end shields of hydrogen
cooled generators must be strong enough to carry shaft seals. In large generators the frame is
constructed as two separate parts. The fabricated inner cage is inserted in the outer frame
after the stator core has been constructed and the winding completed. Stator core: The stator
core is built up from a large number of 'punching" or sections of thin steel plates. The use of
cold rolled grain-oriented steel can contribute to reduction in the weight of stator core for two
main reasons:
a) There is an increase in core stacking factor with improvement in lamination cold Rolling
and in cold buildings techniques.
b) The advantage can be taken of the high magnetic permeance of grain-oriented steels of
work the stator core at comparatively high magnetic saturation without fear or excessive iron
loss of two heavy a demand for excitation ampere turns from the generator rotor.
Stator Windings
Each stator conductor must be capable of carrying the rated current without overheating. The
insulation must be sufficient to prevent leakage currents flowing between the phases to earth.
Windings for the stator are made up from copper strips wound with insulated tape which is
17
impregnated with varnish, dried under vacuum and hot pressed to form a solid insulation bar.
These bars are then place in the stator slots and held in with wedges to form the complete
winding which is connected together at each end of the core forming the end turns. These end
turns are rigidly braced and packed with blocks of insulation material to withstand the heavy
forces which might result from a short circuit or other fault conditions. The generator
terminals are usually arranged below the stator. On recent generators (210 MW) the windings
are made up from copper tubes instead of strips through which water is circulated for cooling
purposes. The water is fed to the windings through plastic tubes.
18
The hydrogen cooling system mainly comprises of a gas control stand, a drier, an
liquid level indicator, hydrogen control panel, gas purity measuring and indicating
instruments.
The system is capable of performing the following functions:
I.
Filling in and purging of hydrogen safely without bringing in contact with air.
II.
Maintaining the gas pressure inside the machine at the desired value at all the times.
III.
Provide indication to the operator about the condition of the gas inside the machine
i.e. its pressure, temperature and purity.
IV.
Continuous circulation of gas inside the machine through a drier in order to remove
any water vapor that may be present in it.
- 117500 KVA
2. Voltage
- 10500V
3. Speed
- 3000 rpm
4. Hydrogen
- 2.5 Kg/cm2
5. Power factor
- 0.85 (lagging)
19
Chapter-7
Figure7.1ControlUnit
20
Chapter-8
TRANSFORMER
8.1 INTRODUCTION
A transformer generally consist of one or more coils (windings) of conducting wire, wound
on a former (bobbin) that surrounds the centre limb (sometimes all limbs) of a circuit of
magnetic material (core). The winding wires are insulated and the core is made from thin
sheet steel plates known as laminations (this reduce eddy current losses). The assembly is
held together by metal cheeks known as clamps, these clamps are held in place by long
screws that are insulated from the rest of the structure (again to limit eddy currents). The
winding wires are either made off to terminals mounted on the clamps or the wire may leave
the coil by flying leads.
21
and reducing eddy current that may occur perpendicular to the plane of lamination.
Sometimes one or both sides of a lamination are sprayed with lacquer for insulation purposes.
Laminations are mostly at power distribution frequencies of 50 Hz or 60 Hz and audio
frequencies; if higher frequencies (up to a hundred or so kHz) are envisaged then ferrite or
other sintered iron oxide compounds are used to make solid split cores. Commonly used
versions are RM Cores and ETD cores. The liked pages also give some rudimentary design
details.
The laminations when assembled from an interleaved stack or core. The
interleaving is usually to avoid any gaps in the magnetic circuit as air is much less permeable
to magnetic flux than iron and steel.
The magnetic flux runs around the two side limbs and combines in the centre limb
which is twice the area of a single side limb, thus keeping flux density constant. The flux
lines that are indicated in red in the diagram at right would follow a slightly higher path near
the corner fixing holes, than my graphic skills can reproduce. It should be noticed that there is
practically zero flux in the centre of the long side and fixing holes or notches are common at
this point.
The holes in the core are known as windows or window spaces and in an
assembled component they are filled by coils wound on a bobbin. Coil formers or bobbins are
of two types known as plain or split, the one shown at left is plain and the other at right is
the split version.
Bobbins these days are mainly injection moulded in plastic, but larger ones often
have paxolin or balkanised paper board cheeks. Occasionally, transformers are constructed
with two or more independent bobbins, each having its own winding(s). this method of
construction is rare, but has its uses at very high voltages( above 3,000 volts). The windings
or coils that are wound around these bobbins can be either single coils or multiple ones.
Single coils are a type known as Auto Transformers and we will not deal any further with
them as they are generally not applicable to the type of project that I get involved in.
Multiple coil types are known as double wound and the windings fall into two
subdivisions Primary and Secondary generally there is only one primary although it
may be divided into two or more portions. Secondary windings may be of any number. Coils
22
may be wound side by side on split bobbins or may be wound on top of one another with a
suitable insulation between. Generally the primary or input winding is completed first as the
innermost coil then layers of plastic or paper are placed over the completed primary and this
is then used as a base upon which further windings are made.
23
or
24
Chapter-9
BOILERS
A boiler is a closed vessel in which steam is produced from water by combustion of fuel.
Classification of boilers: 1. Horizontal, vertical and inclined.
2. Fire tube and water tube.
25
te Heat Recovery
Boiler
flue
gas to
atmosphere
HP drum pressure
drum
HP
boiler
LP drum
pressure
drum
LP
boiler
HP
and
LP
circulating
pumps
Temp.110*C
64bar
condensate preheater
from HP feed pumps
HP economiser1
LP economiser
from LP feed pumps
LP evaporator
6bar
LP superheater
LP steam to LP turbine
Temp.225*C
HP economiser2
HP evaporator
HP superheater1&2
HP steam to HP turbine
Temp.485*C
Flue gas
after
gas turbine
Temp.505*C
26
An evaporator is the component of a refrigeration system and is used to extract heat from the
chamber is to be kept at low temperature. The refrigerating liquid enters the evaporator,
absorbs latent heat from the chamber at constant pressure and comes out as a .
3. Economizer
The function of an economizer in a steam generating unit is to absorb heat from the flue gases
and add this as sensible heat to the feed water before the water enters the evaporative circuit
to the boiler .Advantages of economizer
The temperature between various parts of boiler is reduced which result in reduction of
stresses due to unequal expansion .Evaporative capacity of the boiler is increased. Overall
efficiency of the plant is increased.
4. Air Pre heater
An air pre heater is used to recover heat from flue gases. It is installed between the chimney
and economic.
5. De aerator
It is used to remove air from water as air carries oxygen which is corrosive in nature so to
protect the various parts of boiler from corrosion. We add the hydrazine (NH 2=NH2) in to the
water which react with O2 and makes the pure water.
6. De super heater
It is used keep the temp. Of super heated steam constant. By spraying of some amount of
water over the superheated steam, we can decrease the temp. of steam to keep it at constant
temp. About 5250 C.
9.3 WHRB-SPECIFICATIN
1. Registration No
RJ-661-RJ 666
Wagner-Biro AG
a. Graz-Vienna, Austria
3. Manufactured For
27
a. Corporation (NTPC)
4. Contract No.
01/CC/9505-001-01-1505
5. Type of Boiler
Forced Circulation
6, 4 m
Length:
18, 5 m
Height:
28,0 m
DESIGN DATA:
HP-Part
LP-Part
Cond. Rec.
Design Pressure:
83 bar (g)
bar (g)
15 bar (g)
73 bar (g)
5, 5 bar (g)
11 bar (g)
B2
B3
B1
B2
B3
B1
B2
B3
2994
2995
2990
2991
2992
2997
2998 2999
Water tubes:
8990 m2
23859m2
584 m2
6715m2
-
162, 6 t/h
39, 1 t/h
56 t/h
488/5010C
2070C
1600C
Firing
Year of Manufacture
1988
Mass flow:
28
29
First of all the water from Right main canal is taken in to two reservoirs and from
these reservoirs the water is taken into the water house. Three pumps are used for pumping
this water into aerator. The function of aerator is to add oxygen to the water and to remove
dust particles from the water. From this; water goes to small reservoir, in which chlorination
is done to remove the algae, bacteria and other micro organisms present in the water. After
this the water goes to fore bay storage tank and from here, it goes to pump house where six
pumps are used. Three pumps are used to supply water to De-mineralized water & other three
are used to supply water to Effluent treatment plant. When the water reaches to the pre
treatment plant it is again passed from the aerator, to add oxygen to it. Now water rushes to
stilling chamber where chlorination is done to water for cleaning other micro organisms. The
flow of water at this point can be known by orifice flow meter. Now water is sent to two
clarifiers, from which anyone can be used at a time. In the clarifiers polymer & alum is added
in the centre of the tank purpose of addition of the alum is that it increase the size of small
impurities that are present in the water, but cant be seen with help of our naked eye & the
function of the polymer is to bond that particles. Now the impurities can be easily removed.
The clarifier consists of three parts is inner most tank in which first water goes. The sludge
settles down & in taken to the sludge put & the clear water is taken to the gravity sand filters.
G.S.F. consists of four layers. First layer consists of large gravel. Second layer consists of
medium size gravel. On the top of that is small size gravel & at top most is present the layer
of sand. From these G.S.Fs the water gets more purified and it goes to D.M. plant.
30
CONCLUSION
I have studied about the power plant, especially in ANTA. Studied about gas power plant,
especially natural gas could be used for power generation in gas power plant. It is very
economical but less efficient. Mainly methane (CH 4) is used as fuel. It is very profitable in
case of pollution. It is very less polluted. At place of fuel naphtha is used in alternate form.
But it is very costly and polluted. So it is used in very few shortages. This is very profitable
plant because it has combined cycle plant. According to combined cycle plant less
temperature gas will be recycled and used for generation of power. ANTA gas power plant
has four units in which three gas units and one steam unit. ANTA gas power plant has more
plants for reduction for pollution approximately 1.8 lac trees.
31
BIBLIOGRAPHY
1
2
3
4
5
32
33