NATIONAL INSTITUTE OF TECHNOLOGY

AGARTALA, TRIPURA
AN INPLANT WINTER TRAINING REPORT ON
135MW AgGBPS, NEEPCO Ltd.

(A Govt. of India Enterprises)

SUBMITTED IN THE PARTIAL FULFILLMENT OF THE DEGREE

IN BACHELOR OF TECHNOLOGY IN MECHANICAL ENGNEERING

SUBMITTED BY:- TUSHAR DEB

ENROLLMENT NUMBER:- 21UME003
BRANCH:- MECHANICAL ENGINEERING
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 135MW, AGARTALA GAS BASED POWER STATION
(AgGBPS)
NEEPCO, INDIA

(A Govt. Of India Enterprises)

CERTIFICATE
This is to certify that TUSHAR DEB, B.Tech (6th semester), reg. no:
2113461 of the department of mechanical engineering of National
Institute of Technology, Agartala, Tripura has successfully completed this
industrial training from 16/12/2023 to 30/12/2023 under my close
supervision. During the training period he has successfully submitted
report on “Industrial training at AgGBPS, NEEPCO” related to various
plant and instruments used in power plant division. While during the
training period in AgGBPS, NEEPCO, trainee TUSHAR DEB was seen
to be punctual, sincere and hardworking and his behavior is very good.
We wish him all success in life.

Training Co-ordinator Mentor

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 ACKNOWLEDGEMENT

I would like to express our gratitude to Dr. Pritam Das (H.O.D), Dept.
of mechanical engineering National Institute of Technology Agartala,
Tripura for allotting this training and supporting us throughout the work.
I would like to express a deep sense of gratitude and thanks to Mr. Nanda
Basumatary, H.O.P of AgGBPS, NEEPCO without whose permission
and wise counsel and able guidance, it would have not been possible to
pursue my training. In this manner the help rendered by Mr. Nirup
Sarma DGM (E/M) and Mr. Gopal Karmakar DGM (E/M), for
experimentation is greatly acknowledged. I would also like to thanks Er.
Joydeep Bhattacharjee (Dy. Manager), Er. Atanu Saha (Asst. Engr.)
and Er. Abhijit Lodh (Asst. Engr.)
Finally, I would also like to express my indebtedness to all who have
directly or indirectly contributed to successful completion of industrial
training. At last, but not the least I would like to thanks all the staff
members of NEEPCO who helped me immensely during my stay.

Sincerely

TUSHAR DEB
3rd Year, 6th semester B.Tech. Mechanical Engineering
National Institute of Technology Agartala, Tripura

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 Abstract

I have undergone 15 days in plant training in AgGBPS, NEEPCO

where I learned many things theoretically as well as practically. As
we know, that field of fossil fuel-based technologies. Natural gas
combined cycle (NGCC) power plant we currently at the best position
for electricity generation, having efficiency close to 60% since this
type of power plant is new for me, I got an exposure to it. I learned
the working of various type of machine like turbine, generators,
boilers, and pumps etc. I learned about water filtration techniques,
Demineralization process, working of boilers, cooling systems, Gas
turbine and steam turbine, Electricity Transmission and distribution
in switch yard. This training provided me the much needed Industrial
Exposure and will definitely be helpful in coming years.

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➢ Table of contents:

SL NO Description Page no

• Introduction

➢ NEEPCO 8-11
1. ➢ Agartala Gas Based Power
Station (AgGBPS)
➢ Specifications
➢ Combined cycle power station

• Gas Turbine and Power Generation

2. ➢ Working principle 12-16

➢ Industrial gas turbine for power generation
➢ Advantages and limitations of gas turbine

• Heat recovery steam generator (HRSG)

3. ➢ Principle of HRSG. 17-24

➢ Part of HRSG.

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 • Water treatment facilities (for
steam turbine)/DM PLANT

➢ Source of water 25-34

4.
➢ Reservoir
➢ Treatment process
➢ Storage

• Steam turbine and power generation

➢ Production of steam. 35-41
5. ➢ Steam turbine and its accessories.
➢ Steam turbine principles and working.

• Air cooled condensation facility

42-44
6. ➢ Condensate storage tank.
➢ Condensate extraction pump.
➢ Ejector.

• Lubrication system 45-47

7.

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 • Electrical systems
➢ Generator
➢ Switch yard
➢ Transformers
➢ Bus duct
8. ➢ Unit auxiliary transformer (UAT)
➢ Emergency Diesel Generator (EDG) 48-55
➢ Lightening arrestor (LA)
➢ Isolator
➢ Current transformer (CT)
➢ Potential transformer (PT)
➢ Bus bar

9. • Conclusion
56

10. • Safety precautions. 57

11. • References.
58

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 1. Introduction
➢ NEEPCO
:-North Eastern Electric Power Corporation Limited (NEEPCO) is a schedule -A
‘MINI RATNA'

Category-1 Central public sector Enterprise owned by the Government of India

under the Ministry of Power, formed on 2 April 1976 to plan, investigate, design,
construct, generate, operate and maintain power stations in the North Eastern Region
of the country. It has 60% of total installed capacity of North East region, which is
2057 MW. With its headquarter in the charming town of Shillong, the capital of
Meghalaya, NEEPCO is a power sector enterprise with its plants in various states of
North East India.

The various projects of NEEPCO that are completed are:

• 600 MW Kameng Hydro Electric Project - ARUNACHAL PRADESH

• 405 MW Ranganadi Hydro Electric Project - ARUNACHAL PRADESH
• 110 MW Pare Hydro Electric Project - ARUNACHAL PRADESH
• 275 MW Kopili Hydro Project — ASSAM
• 291 MW Assam Gas based Power Plant — ASSAM
• 60 MW Tuirial Hydro Electric Project- MIZORAM
• 75 MW Doyang Hydro Electric Project-NAGALAND
• 135 MW Agartala Gas Based Power Station - TRIPURA
• 101 MW Tripura Gas Based Power Plant - TRIPURA
• 5 MW Grid Interective Solar Power Project — TRIPURA

The total production capacity of all NEEPCO plants combined is 2057 Mw.

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➢ AGARTALA GAS BASED POWER STATION(AgGBPS)

This is a 135 MW (4 x 21 MW + 2 x 25.5 MW) Combined Cycle Power Plant

is located in the West Tripura District of the state Tripura near the capital town
of Agartala. It is called the Agartala Gas Based Power Station (AgGBPS) and
also Agartala Gas Turbine Combined Cycle Power Plant (AgGBPS).
Initially the project consisted of 4 Gas Turbines of 21 MW each of European
Gas Turbine make operating on natural gas obtained from the gas fields of M/S
GAIL at Tripura. The Project was financed through the budgetary support of
the Government of India and partially through external commercial borrowings
from the Deutsche Bank, Germany. The Project was completed in 1997-98 at a
cost of Rs.322.55 Crores with a 50:50 debt equity ratio.

The plant has been converted to combined cycle power plant with installation
& commissioning of 4 Nos. HRSG of Thermax make and 2 Nos. Steam Turbine
of Siemens make of capacity 25.5 MW each. The project was financed through
internal resource and external commercial borrowings from SBI, Singapore
with 30:70 debt equity ratio. The plant is presently running as a combined cycle
unit with 2 (two) modules consisting of two Gas Turbines, two HRSGs and one
Steam Turbine in each module.

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 Specification

Name: AGARTALA GAS BASED POWER STATION

Capacity: 135 MW (4 x 21 MW +2 x 25.5 MW)

Location: Ramchandra Nagar, TRIPURA (WEST)

Date of Commercial Operation (COD):

GTG-1 1-April-1998

GTG-2 1-April-1998

GTG-3 1-April-1998

GTG-4 1-August-1998

STG-1 1-September-2015

STG-2 29-July-2015

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➢ Combined Cycle Power Plant
Combine cycle is a power producing engine or plant that employs more than one
thermodynamic cycle. Heat engine are only able to use a portion of the energy of
their generation usually less than 50%. The remaining heat from combustion Is
generally wasted.

power plant (CCPP) or combined cycle gas turbine (CCGT) plant, as gas turbine
generator generates electricity, and waste heat is used to make steam to generate
additional electricity via a steam turbine, this last step enhances the efficiency of
electricity generation. As a rule, in order to achieve high efficiency, the
temperature difference between the input and output heat levels be as high as
possible. This is achieved by combining the Brayton (gas) and Rankine (steam)
thermodynamics cycle.

At NEEPCO AgGBPS a combined cycle facility Is set up. The facility consists
of 4 Gas Turbines and 2 Steam Turbines. The gas turbines use natural gas as fuel
for electricity generation. The heat ejected from the gas turbine is not released
into the atmosphere rather it is recovered using

Heat Recovery Steam Generators (HRSG) and is further used to heat water in
the boilers to make steam to run the steam turbines. There is one HRSG for every
gas turbine.

Fig: SCHEMATIC DIAGRAM OF COMBINED CYCLE POWER PLANT

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 2. Gas Turbine and Power
generation
➢ Working principle
“The gas turbine basically operates on the principle of the Brayton cycle,
where compressed air is passed and mixed with the fuel, and burned under
constant pressure conditions. The resulting hot gas is allowed to expand
through a turbine to perform work.”

The Gas turbine engines derive their power from burning fuel in a combustion
chamber and using the fast-flowing combustion gases to drive a turbine in much
the same way as the high-pressure steam drives a steam turbine. A simple gas
turbine is comprised of three main sections a compressor, a combustor, and a
power turbine.

FIG: SCHEMATIC DIAGRAM OF SINGLE LINE GAS TURBINE

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 Fig: Gas Turbine at AgGBPS

• Parts of the Gas turbine:

1. Compressor:
- The compressor is an apparatus used to increase the pressure of air taken from
the atmosphere. In gas turbine power plants, rotatory type compressors are
generally used.

- The air at atmospheric pressure is drawn by the compressor through an air filter
which removes the dust from the air. The rotatory blades of the compressor
push the air between the stationary blades to increase the pressure. Therefore,
the air at high pressure is available at the output of the compressor.

2. Combustion chamber:
- The combustion chamber is an apparatus used to increase the temperature
of the compressed air. Here, the air at high pressure from the compressor is
brought to the combustion chamber through the regenerator.
- In the combustion chamber, heat is added to the compressed air by burning
of fuel oil. The fuel oil is injected through the burner into the combustion
chamber at high pressure to ensure the atomisation of oil and its thorough
mixing with the air. Consequently, the combustion chamber attains a very
high temperature (about 1700 °C). The gases produced by the combustion
are suitably cooled to 700 °C to 800 °C and then delivered to the gas turbine.

3. Starting motor:
- Before starting the gas turbine, the compressor has to be started. For this
purpose, an electric motor (M) is mounted on the shaft of the turbine. This
motor is energized by the batteries. However, once the power plant is
started, a part of mechanical power of the turbine drives the compressor and

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 there is no need of the auxiliary motor now.

4. Gas Turbine:
- The gas turbine is a device which converts heat energy of hot gases into
mechanical energy. The products of combustion consisting of a mixture of
gases at high temperature and pressure are expanded in the gas turbine and
does the mechanical work, i.e., it converts the heat energy into mechanical
energy.

5. Alternator:
- Each alternator is coupled to a steam turbine and converts the mechanical
energy of the turbine into electrical energy. The alternator may be hydrogen
or air-cooled. The necessary excitation is provided by means of main and
pilot exciters directly coupled to the alternator shaft.

Fig: Schematic diagram of the parts of gas turbine

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➢ Thermodynamic Explanation of working
of the gas turbine:-
-“The working of the gas turbine is completely based and performed on the
basis of the Braton Cycle where combustion and heat release are done at
constant pressure rate”.
- The thermodynamic process used by the gas turbine is known as Brayton cycle.
According to the carnot cycle in which efficiency is maximized by increasing the
temperature difference of the working fluid between the input and output of the
machine, where as in the Brayton cycle the efficiency is maximized by increasing
the pressure difference across the machine.

The gas Turbine is basically comprised of the three main parts: Compressor
(Axial), Combustor and a turbine.
Working: The working fluid, air is compressed in the compressor (Adiabatically
compression- no heat gain or loss), then the air and fuel is mixed and burned
by using an ignition under constant pressure condition in the combustion chamber
(constant pressure heat addition). The resulting hot gas is then expanded
thoroughly through the turbine to perform work (adiabatic expansion).

Fig: (i) P v/s V ii) T v/s S diagram of Brayton Cycle

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➢ Advantages and Limitation of the Gas
Turbine

• Advantages:
- It is simple to design and construct as compare to steam turbine

- In gas turbine boiler are not required so they are compact and much smaller
in size as compare to steam turbine.

- It has low operating and less Maintenance cost.

- Less amount of loss are done in operation of the gas turbine.

- And easy to operate as compare to the steam turbine.

• Limitations:

- The net output of the gas turbine is low since greater power is used for
driving the compressor.

- The overall efficiency of the plant is low as 20% because of the exhaust
gases still containing heat.

- We can increase the efficiency by using the combine cycle to use that
exhaust gas efficiently as compare to release it into atmosphere.

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3. Heat Recovery Steam Generator
(HRSG)
The HRSG is basically a heat exchanger, or rather a series of heat exchangers, It
is also called a boiler, as it creates steam for the steam turbine by passing the hot
exhaust gas flow from a gas turbine or combustion engine through banks of heat
exchanger tubes, The HRSG can rely on natural circulation or utilize forced
circulation using pumps. As the hot exhaust gases flow past the heat exchanger
tubes in which hot water circulates, heat is absorbed causing the creation of steam
in the tubes. The tubes are arranged in sections, or modules, each serving a
different function in the production of dry superheated steam. These modules are
referred to as economizers, evaporators, superheaters/reheaters and preheaters.

Fig: Combined Cycle Utility Heat Recovery Steam Generator Diagram

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 ➢ Principle Of Operation:
The economizer is a heat exchanger that preheats the water to approach
the saturation temperature (boiling point), which is supplied to a thick-
walled steam boiler. The boiler is located adjacent to finned evaporator
tubes that circulate heated water. As the hot exhaust gases flow past the
evaporator tubes, heat is absorbed causing the creation of steam in the
tubes. The steam-water mixture in the tubes enters the steam boiler where
steam is separated) from the hot water using moisture separators and
cyclones. The separated water is recirculated to the evaporator tubes.
Steam boilers also serve storage and water treatment functions

An alternative design to steam boilers is a once-through HRSG, which

replaces the steam boiler with thin-walled components that are better
suited to handle changes in exhaust gas temperatures and steam pressures
during frequent starts and stops.

This provides the following attributes:

➢ Maintains vertical tube module arrangement in horizontal gas

path as proven in boiler- type boilers.
➢ Replaces HP boiler with thin-walled components (separator), which
improves operational flexibility.
➢ Maintains natural circulation flow characteristics and therefore
assures the flow stability and even heat distribution.
➢ Requires no changes in HP economizer and HP superheater.
➢ Retains proven low pressure and intermediate pressure boilers.

In some designs, duct burners are used to add heat to the exhaust gas
stream and boost steam production, they can be used to produce steam
even if there is insufficient exhaust gas flow.
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Saturated steam from the steam boilers or once-through system is sent to the
super-heater to produce dry steam, which is required for the steam turbine.
Preheaters are located at the coolest end of the HRSG gas path and absorb energy
to preheat heat exchanger liquids, such as water/glycol mixtures, thus extracting
the most economically viable amount of heat from exhaust gases.

The superheated steam produced by the HRSG is supplied to the steam turbine
where it expands through the turbine blade imparting rotation to the turbine shaft.
The energy delivered to the generator drive shaft is converted into electricity.
After exiting the steam turbine, the steam is sent to a condenser which routes the
condensed water back to the HRSG.

Fig: HRSG (Heat Recovery Steam

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 ➢ PARTS OF HRSG:

- The heat Recovery Steam Generator have the following parts:

• Economizer:

The Economizer sections raise the boiler food water to a suitable approach
temperature. Evaporator: The HP and LP evaporator systems are of natural
circulation. Each pressure evaporator section consists of evaporator heat transfer
section, steam boiler, down comers, and risers. The heat transfer section consists
of multiple rows of finned tubes, Lower and upper headers, manifolds, vents and
drains are included.

• Super-heater: The super-heater section is designed to increase the

steam temperature to the temperature stated in heat balance.
Superheated steam has a high energy content and is free of moisture.
Required crossover tubes, vents, drains and safety valves are included.

• Thermal insulation: Thermal insulation is applied to piping, valve,

tank and equipment having an operating temperature in excess of 60
°C.

• Stack: Typically, the HRSG stacks are of self-supporting and

constructed of carbon steel. The HRSG is equipped with an access door
located for convenient access in the base section, drains, connecting
ductwork with the expansion joint access platforms and vertical
ladders with enclosing safety cage to the platform level.

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• Boiler Feed Pump (BFP):
The boiler feed pump is employed to feed the water from LP drum to HP drum
through Economizer. NEEPCO uses16 stage feed pump which is powered by a
250 KW motor rotating at a speed of 2970 rpm. The speed of the pump is
controlled by hydraulic coupling or scoop. Mechanical sealing is provided to the
boiler feed pump. To maintain a stable thrust on the boiler a balancing line is
installed in the BFP stuffing box, NEEPCO have arranged two BFP for each of
the HRSG, among which one is employed to service & another is kept in standby.

• Blowdown and drain system:

- Piping and valves are provided for each HRSG to collect blowdown
water, boiler overflow water and steam drains. Each HRSG is fitted
with two blowdown facilities, one may be designed to operate on a
continuous and the other one on an intermittent basis. Both are led to
the blowdown flash vessel.
The same applies for the boiler overflow (Emergency blow down) An
intermittent blow down connection is located on each of HP and LP
evaporator. This blowdown is used to reduce the solids collected in
the evaporator. It is usually operated intermittently, once a shift or
shortly after the HRSG is shut down and still pressurized. Also, this
blowdown is used to lower the boiler level in case of abnormal high
level during operation.
The continuous blowdown connection is used during normal
operation. In conjunction with the chemical feed system, to maintain
proper steam boiler water quality.
• Exhaust gas inlet duct:
- The ductwork is properly stiffened, reinforced and complete with
expansion joint and necessary doors. HRSG heat exchanger chamber:
The HRSG heat exchanger chamber is constructed of carbon steel
casing externally reinforced with structural steel. All structural steel
is seal welded to the casing to prevent corrosion behind the structural.

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• Dosing system:
- A chemical dosing system to dose phosphate solution to the boiler water
has been provided to condition the boiler water to control scale forming
components. Under these two types of dosing is done namely HP
dosing& LP dosing.

- In HP Dosing tri-phosphate is dosed into the steam drum to maintain a

phosphate concentration of 40 to 42 PPM and pH of 10.8 to 114. The
Phosphate has the capacity to convert hardness producing insoluble
calcium/magnesium salts to soluble sodium salts, which are drained
through the blow down. The dosed phosphate desired alkalinity to the
boiler water. An alkaline pH minimizes the possibilities of corrosion.
Dosing of phosphate to the Boiler water is to be done in a manner that it
quickly mixes with the whole boiler water. To enable this, a perforated
pipe has been laid along the length of the drum and connected to the HP
dosing line through a valve [HP 054] and a NRV [HP 055]

- In LP Dosing hydrazine is dosed to the LP drum as needed, to remove

the excess oxygen dissolved in the De-mineralized water. The dissolved
oxygen can accelerate the corrosion, by getting in touch with iron
surface. That’s why LP dosing is used to eliminate the chance of
corroding of the surface.

• Boiler Feed Pump (BFP):

• The boiler feed pump is employed to feed the water from LP drum to
HP drum through Economizer. NEEPCO uses 16 stage feed pump
which is powered by a 250 KW motor rotating at a speed of 2970 rpm.
To maintain a stable thrust on the boiler a balancing line is installed in
the BFP stuffing box, NEEPCO have arranged two BFP for each of the
HRSG, among which one is employed to service & another is kept in
standby.

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• High pressure (HP) Steam Drum:
• The steam drums are steam/water separators, storage tanks, and water
treatment sites for steam purity control. The steam/water mixture
entering the drum from the riser tubes usually 5-10% steam
depending on the boiler load and pressure. In the steam drum,
saturated steam is separated from the steam/water mixture. The
separator steam rises up through the drum as feed water enter the
drum from economizer.
• The separated water from the steam/water mixture is then recirculate
together with the feed water to the heat absorbing evaporator tubes
through the circulation loop. The water flows down the cylinder wall
by gravity and is discharged from the cyclone through an annulus
located below the water level. The separated water returns to the
boiler cycle virtually free of steam. Each steam drum head includes
an elliptical manhole, providing access to drum internals and
connections for the remote level indicators, level gauges, and other
control instruments. Each steam drum also contains. Connections for
pressure safety relief valves, vents, pressure indicators, nitrogen
blankets, downcomers, riser pipes, continuous blow down, chemical
feeds and other control instruments. The drum vents are used to vent
air during boiler filling and venting non- condensable gas during start
up. Its rated pressure is 66Kg/cm²

• Low Pressure (LP) Steam Drum:

- The water enters the drum from CEP and from DM plants during

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 initial filling. To increase its efficiency the water is taken through
CPH when generation reaches 7MW. It also consists of drum vent.
Its rated pressure is 6kg/cm.

• Diverter, Damper and Bypass Stack System –

- The function of the diverter damper and bypass stack system is to

conduct exhaust gas from the GT exhaust to either the HRSG inlet
or to the atmosphere. The main equipment which is responsible for
the direction of the exhaust gas is diverter damper. Many CCPP
cannot operate in simple cycle mode through the bypass stack
because the combustion turbine emissions will exceed the plant's
air permit limits. In normal operation the exhaust gasses must pass
through the selective catalytic reduction (SCR) located in the
HRSG which reduces the carbon monoxide (CO) and Nitrogen
Oxide (NOx) emissions below the plant's air permit levels.

- Many CCPP choose not to run in simple cycle mode through

the bypass stack because it is not economical without the
efficiency benefit of the steam turbine bottoming cycle.
- The system consists of sub-systems with the following functions:
1. Diverter damper to divert the exhaust gas pass.
2. Bypass stack with silencer to conducts exhaust gas to the
3. Atmosphere.
4. Seal air unit to seal the diverter damper.
5. Guillotine damper and shut-off the exhaust gas to HRSG.

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 4. WATER TREATMENT FACILITY
(DM PLANT)

Water treatment is essential before steam generation. Water obtained from

various sources contains different types of impurities, which must be removed
before converting water into steam. If impurities are not removed this can damage
various equipment of the steam power generation unit like boiler, turbine blades,
etc. or significantly reduce their lives. Water treatment is carried out in DM Plant
(De- mineralization)

Sources of Water:
• There are 3 types of sources of water:-
1. Surface water-River water, lake water, pond water etc.
2. Ground water -Bore water, well water.
3. Sea water-Sea Water.
NEEPCO- AgGBPS uses ground water (bore water) for steam production.

➢ Reservoir:
- Reservoir is used for water storage purpose. Water is taken from here
for DM water process work. High-Rate Solid Contact Clarifier: This
clarifier is a high rate, solid contact, sludge re- circulation type
clarifier, which is minimum time and space and using a minimum
amount of Chemicals, produces an effluent of the highest quality, it
is used principally for clarification, lime softening, silica reduction
or organics reductions of water and waste water containing
suspended solids, colour and organic impurities. As such, it provides
a means for chemical addition and mixing, Flocculation and up flow
clarification in a single unit.

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 Fig: Reservoir
➢ Water Treatment Process:
- In power plant water is known as the heart of the plant, so it is most
necessary to supply salt free water for process. The demineralization
is the process of removing mineral salts from water by using ion
exchange process. The D.M water reduces the scale formation,
Deposition and corrosion of tubes. It increases the life of pipes and
tubes in plant. It prevents the deposition of minerals in turbine
blades. It removes Mineral salts in the form of cations such as
sodium, calcium, iron, copper and anions such as chloride, sulphate,
nitrate etc. Also, various other parameters of water like hardness, pH
(acidity-alkalinity), conductivity, etc. are check to make the water
have optimum characteristics for steam production.

- Water Treatment are done in two stages

2) Pre-Treatment

1) De-Mineralization

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➢ Pre-Treatment:
• First water is extracted from natural underground reserves using
bore-well and stored in reservoir. This water contains a lot of
impurities specially mud, silica, salts, and other solid and gaseous
impurities in dissolved and suspended form.

• The water from the reservoir is then passed through Degasser /

Aerator where itis passed in a zig-zag motion. This removes the
gaseous impurities and some solid impurities.

• The water is then treated with Alum and lime. Alum acts as a
coagulant and removes suspended solids from water. Lime
acts as pH booster.

• Then the water is sent for filtration. Filtration consists of passing

the water through packed layers of sand charcoal etc. Now
bleaching powder is added to the water that has come out of
filtration. Bleaching powder contains chlorine and hence acts as
disinfectant.

Fig: Degasser/Aerator

NOW THE WATER SENT TO DE- MINERALISATION

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➢ De-Mineralization Of Water:
- De-mineralization of water has 3 main steps, they are

1. Activated Carbon filtering

2. Strong Acid Cation (SAC) Treatment

3. Strong Base Anion (SBA) Treatment

4. Mixed Bed treatment

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 • Activated Carbon filtering:

- After pre-treatment the water is stored in tanks containing activated

charcoal/carton. It is employed for the process of removing organic
compounds and extracting free dire from water, thereby making the
water suitable for discharge or use in manufacturing processes. The DM
Plant at NEEPCO AgGBPS has two activated carbon filtering tanks
which perform the filtration process.

• Strong Acid Cation (SAC) Treatment:

- After activated carbon filtering, the water is sent for Strong Acid
Cation (SAC) treatment in SAC tanks. These tanks contain strong
acid cation resins. The strongly acidic cation exchange resins are
bead-like products which have a sulfonic acid group in the cross-
linked styrene frame. SAC is a cation exchange process. There are
two SAC tanks in the DM plant to carry out this operation. After
SAC treatment the hardness of water is removed and pH of water
obtained is less than 3.5.

• Strong Base Anion (SBA) Treatment:

- After SAC treatment the water is sent for Strong Base Anion
(SBA) treatment in SBA tanks. It contains strongly basic anion
exchange resin with quaternary ammonium groups
Incorporated into the styrene frame. SBA is an anion
exchange process. There are two SBA tanks in the DM plant
to carry out this operation. After SBA treatment Silica content
In water is less than 0.2 pm, Conductivity less than 5 micro
siemens and pH obtained is 7.8 to 8

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 • Mixed Bed Treatment:

- After passing water through cation then anion exchanger it is

passed through mixed bed unit. In mixed bed cation and anion
resins are mixed and while water passes through it, as it passes
through thousands of cation/anions exchanger resulting final
effluent of very good quality water. It is similar to conventional
ion exchanger a cylindrical steel vessel. Internally rubber lined
containing resin bed above which there is free space to allow
expansion of resin when back washed. In addition to the usual
distributors, a mixed bed is fitted with a center distribution and
collection system. At the time of regeneration, the bed is back
washed. This expands the resin bed and allows the heavy cation
resin to sink to bottom and lighter anion resin rises to top. After
some time when back wash is stopped the resins settle without
upsetting the separation. There is a well- defined interface between
the cation and anion resin bed and that interface is just at the level
of center distributors Anion resin can be regeneration with caustic
and rinsed. Spend caustic solution and rinse water can be
withdrawn through the center distributors. After this cation resin
can be regenerated and rinsed. In that case caustic will now be acid
inlet/rinse water inlet. When both the resins are regenerated and
rinsed the excess water is drained down to the surface of the bed
and the resins are mixed thoroughly, with the help of air blowing.
The air is blown in through bottom distributors and out through the
air release at the top. After proper mixing the space above the bed
is filled from above and unit is put into final rinse.

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 Fig: ACF Tank, SAC Tank, SBA Tank
• Degasser:

- Degasser is an integral part of any demineralization plant,

where it is generally placed between cation and anion
exchanges and removes Carbon Dioxide, which is generated
by dissociation of carbonic acid at cation outlet water. In this
Degassing processes, Degasser Tower is utilized, which is
made coating. Low air pressure is generated at the bottom of
the tower that drives out CO2 and the degassed water is
collected in a sump beneath the tower.

Fig: Mixed Bed

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 Fig: Bleaching Powder Fig: Retention Chamber

Fig: Pre-Treated water Fig: Dual Media Filter

32 | P a g e
Quality of Effluent Water:
The quality of effluent water of SAC, Degasifier, SBA & MB will have
the following property.

SAC Outlet Water Parameter

pH at 25 ℃ 2.8 to 3.5

Free Mineral Acidity Should be Equal to Equivalent Mineral Acidity

(FMA) (EMA)

Hardness ppm as CaCO3 NIL

Sodium ppm as Na+ <0.005

Degasifier Outlet Water Parameter

Residual free CO2 ppm <5.0

SBA Outlet Water Parameter

pH at 25 ℃ 7.5 to 9.0

Total silica SiO2 ppm <0.05

Conductivity(µs/cm) < 2.0 preferably < 1.0

Chloride (ppm as Cl) NIL

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MB Outlet Water Parameter

pH at 25 ℃ 6.8 to 7.2

Total silica SiO2 ppm <0.02

Conductivity(µs/cm) < 0.2

Sodium ppm as Na+ <0.003

34 | P a g e
 5. STEAM TURBINE AND POWER GENERATION

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

generator is steamy driven. Water is heated, turns into steam and spins a
steam turbine which drives an electrical generator. 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. Worldwide, most electric power is produced by steam-electric
power plants, which produce about 86% of all electric generation. The only
other types of plants that currently have a significant contribution are
hydroelectric and gas turbine plants, which can burn natural gas or diesel.
Photovoltaic panels, wind turbines and binary cycle geothermal plants are
also non-steam electric, but currently do not produce much electricity

➢ Steam Production:
Steam is most essential to run a steam turbine. Steam in a power plant is
produced by heating water in boilers. In NEEPCO-AgGBPS the water
required for steam production is obtained from underground natural
reserves using bore well and is purified by the DM plant and then
supplied to boiler. The heat required to make the steam is obtained from
gas turbines by the use of Heat Recovery Steam Generators (HRSG).
There are also Boiler Feed Pumps (BFP) to assist the process. The steam
produced is of two types i.e., Low Pressure (LP) Steam and High Pressure
(HP) steam. Hence two types of Boilers are used i.e., LP Steam drum (For
producing LP steam) and HP Steam drum (for producing HP steam). Both
LP and HP steams are used to run the turbine. After the steam has passed
over the turbine it is condensed to form water which is then again heated
to make steam for the turbine and hence forms a cyclic process. However,
if quality of steam produced is less it can be recovered by allowing de-
mineralized water to enter the boilers from DM plant.

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➢ Energy absorption from steam
-When turbine blades get rotated by high pressure high temperature
steam, the steam loses its energy. This in turn will result in a low pressure
and low temperature steam at the out of the turbine. Here steam is
expanded till saturation point is reached. Since there is no heat addition or
removal from the steam, ideally entropy of the steam remains same. This
change is depicted in the following PV and T-s diagrams. If we can bring
this low pressure, temperature steam back to its original state, then we can
produce electricity continuously.

➢ Heat Addition in Boiler & Rankine Cycle:

-Here external heat is added to the fluid in order to bring fluid back to its
original temperature. This heat is added through a heat exchanger called a
boiler. Here the pressure of the fluid remains the same, since it is free to
expand in heat exchanger tubes. Temperature rises and liquid gets
transformed to vapour and regains its original temperature. This completes
the thermodynamic cycle of a thermal power plant, called Rankine Cycle.
This cycle can be repeated and continuous power production is possible.

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➢ Condenser Heat Rejection - Cooling Tower:
-In order to reject heat from the condenser a colder liquid should
make contact with it. In a thermal power plant continuous supply
of cold quid is produced with the help of a cooling tower. Cold
fluid from the cooling tower absorbs heat from a condenser and
gets tested, this heat is rejected to the atmosphere via natural
convection with the help of a cooling tower

➢ Steam Turbine and its Accessories:

• Steam Turbine:-
A steam turbine is a machine that extracts thermal energy from
pressurized steam and uses it to do mechanical work on a rotating
output shaft. Because the turbine generates rotary motion, it is
coupled to a generator to harness its motion into electricity. Such
turbogenerators are the core of thermal power stations. The steam
turbine is a form of heat engine that derives much of its improvement
in thermodynamic efficiency from the use of multiple stages in the
expansion of the steam, which results in a closer approach to the
ideal reversible expansion process.

The HP and LP steam produced in the boilers is fed to turbine which

turns rotate the blades thus giving mechanical energy to alternator
through reduction gearbox. This turbine is a combination of impulse
and reaction turbine. The exhaust pressure of which is 0.9 kg/cm²
When the steam passes through different stages in turbine the
temperature as well as pressure of steam gets drop and the exhaust
is passed through duct of air-cooled condenser. Before turbine
rolling, bearing gear has to be engaged and should be run for a

37 | P a g e
 minimum 15- 17 hours to increase the casing temperature and to
avoid the expansion of turbine blades. This happen if the HP steam is
directly fed to stationary turbine blades by opening the Emergency
Stop Valve (ESV). Bearing gear is rotates at turbine shaft ata speed
of 108 rpm during starts up Bearing gear is said to an auto engaged
mode so that when the turbine gets tripped it starts automatically.
Bearing gear gets auto engaged when the turbine shaft reaches at a
speed of 350 rpm while shutdown.
There are two Steam Turbines at NEEPCO-AgGBPS. Each turbine
produces 25.5 Mw electricity and in total both produce 51 Mw of
electricity.
When turbine blades get rotated by high pressure high temperature
steam, the steam loses its energy. This in turn will result in a low
pressure and low temperature steam at the outlet of the turbine.
Here steam is expanded till saturation point is reached. Since there
is no heat addition or removal from the steam, ideally entropy of
the steam remains same. If we can bring this low pressure, low
temperature steam back to its original state, then we can produce
electricity continuously.

• Condenser:
Compressing a fluid which is in gaseous state requires a huge
amount of energy, so before compressing the fluid it should be
converted into liquid state. A condenser is used for this purpose,
which rejects heat to the surrounding and converts steam into
liquid. Ideally there will not be any pressure change during this
heat rejection process, since the fluid is free to expand in a
condenser.

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 • Pump:-
At exit of the condenser fluid is in liquid state, so we can use a
pump to raise the pressure. During this process the volume and
temperature (2-3 °C rise) of fluid hardly changes, since it is in
liquid state. Now the fluid has regained its original pressure.

• Boiler:
Here external heat is added to the fluid in order to bring fluid back
to its original temperature. This heat is added through a heat
exchanger called a boiler. Here the pressure of the fluid remains
the same, since it is free to expand in heat exchanger tubes.
Temperature rises and liquid gets transformed to vapour and
regains its original temperature. This completes the
thermodynamic cycle of a thermal power plant, called Rankine
Cycle. This cycle can be repeated and continuous power
production is possible.

• Gland Sealing System:

Gland sealing system is provided to seal the inlet & outlet of a
turbine so that the high pressure steam cannot escape from the
turbine casing, except through the exhaust Gland seating is a low-
pressure system that is led to a sealing gland. The steam seal the
gland, which may either a carbon ring or labyrinth type against air
at the vacuum end of the shaft.

• Pressure Reducing & De-Superheating System (PRDS):

The main function of PRDS is to reduce the temperature & pressure
of HP steam, so that it can be used as motive steam & gland sealing
steam. Usually, water from CEP discharge is sprayed into the steam.
As a result, the temperature as well as the pressure gradually
decreases.

39 | P a g e
 • Boot Tank:
The partially condensate water from turbine exhaust duct is stored
into the boot tank or drain tank. This water sometimes fed to CST
by some drain boot pumps.

• LP and HP Steam Dumping:

This system is used when there is continuous production of steam
and the steam cannot be supplied to turbine due to various faults. It
consists of spraying system through which water coming from
cooling tower is sprayed and the temperature and pressure gets
reduced before entering into exhaust line of Steam turbine which
is then condensed by means of Air-cooled condenser.

➢ WORKING PRINCIPLE OF THE STEAM

TURBINE
The working principle of Steam turbine is based on Rankine cycle and
depends on the dynamic action of the steam. A high-velocity steam is
coming from the nozzles and it strikes the rotating blades which are fitted
on a disc mounted on a shaft. This high- velocity steam produces dynamic
pressure on the blades in which blades and shaft both start to rotate in the
same direction. Basically, in a steam turbine pressure energy of steam
extracts and then it converted into kinetic energy by allowing the steam
to flow through thew nozzles. The conversion of kinetic energy does
mechanical work to the rotor blades and the rotor is connected to a steam
turbine generator which acts as a mediator. Turbine generator collects
mechanical energy from the rotor and converts into electrical energy.
Since the construction of steam turbine is simple, its vibration is much
less than the other engine for same rotating speed.

40 | P a g e
 Fig: Steam Turbine at NEEPCO AgGBPS

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 6. AIR COOLED CONDENSER (ACC)

The exhaust steam from the STG is cooled & condensed by the
air-cooled condenser & stored in the condensate storage tank. It
consists of a huge duct which is later divide into two, followed by
various small pipes which are connected to the common header to
condensate storage tank. There are many heat exchangers attached
with the small pipes to make the process quicker.
There are 6 huge fans which act as air coolers rotating at a rated
speed of 1500 rpm (each fan) for each of the steam turbine. As
there is no pump given to extract the exhaust gas from STG, hence
a negative pressure is maintained inside ACC duct. This process
is usually done by taking ejector into service. It also extracts all
non-condensable gases from duct. The Air- Cooled Condenser
installed in this project is of A-frame shape. There are a total 12
nos. of ACC fans for two STG unit and the blades of each fan are
set at an angle of 15-17° depending upon the voltage consumed
by fan.

Air Cooled Condenser fans runs on 415 volts. When the ACC fans
rotates it provides the cooling medium (air) in the upward
direction (due to set blade action) which makes the exhaust
present in duct to condensate and later is collected in condensate
tank.

42 | P a g e
 Fig: ACC (NEEPCO AgGBPS)

➢ CONDENSATE STORAGE TANK:

The condensate storage water, collected by the air cooling of
steam through ACC is stored in the condensate storage tank. For
intake of the steam through the outlet duct, it is required to
maintain a negative pressure in the line. That's why an ejector
system is installed throughout the ACC line and CST tank. For the
proper maintenance of the pump, it is required to maintain the
level between 60-70%

➢ FIELD DETAILS:

43 | P a g e
 ➢ Condensate Extraction Pump:
The condensate extraction pump extracts the condensed water from
condensate storage tank and delivers it into the ejector. It is also used to
fill up the LP drum during start up if needed through CPH bypass.
NEEPCO has arranged two CEP for each of the steam turbine among
which one is employed for the service and another is kept in the standby.
Ejector:
Steam jet Ejectors are based on the venture ejector principle & operated
by passing motive steam through an expanding nozzle. The nozzle
provides controlled expansion of the motive steam to convert pressure
into velocity which creates a negative pressure or gas are then completely
mixed and then passed through the diffuser, where the gases velocity is
converted into sufficient pressure to meet the predetermined discharge
pressure. The ejector maintains a negative pressure into discharge line,
condensate storage tank. The condensate water from condensate storage
tank is supplied to ejector through condensate extraction pump and then
supplied to gland sealing condensate.

FIELD DETAILS:

44 | P a g e
 7. LUBRICATION SYSTEM

➢ GAS TURBINE LUBE OIL SYSTEM:

“The lubrication oil is the life blood of the gas turbine and it is very
important for the gas turbine to perform its function and to extend
the length between overhauls. Fluid film journal bearings play a
significant role in the machine’s overall reliability and rotor- bearing
system vibration and performance characteristics.”

Turbine engines oil systems can also be classified as a pressure relief

system that maintains a somewhat constant pressure: the full flow
type of system, in which the pressure varies with engine speed, and
the total loss system, used in engines that are for short duration
operation (target drones, missiles, etc.). The most widely used
system is the pressure relief system with the full flow used mostly
on large fan type engines. One of the main functions of the oil system
in turbine engines is cooling the bearings by carrying heat away,
circulating oil around the bearing.
This gas turbine engine has an oil tank. The lubricant oil is supplied
from the tank to the lube pump which pushes liquid throughout the
filter into two different branches. The first branch lubricates the first
journal bearing and additional equipment like fuel, and auxiliary
gear pumps. The second branch lubricates the other bearing and gear
pumps.

45 | P a g e
 Fig: Gas Turbine Lube oil system

➢ STEAM TURBINE LUBE OIL SYSTEM:

Steam turbines are widely used in the power industry as prime
movers for generators. As a paramount component to a company’s
production, these machines generally run on continuous operating
schedules. Maintenance professionals are challenged with
implementing tactics that enhance equipment performance given the
turbine’s extreme operating conditions associated with lengthy
periods of time in service, such as high temperatures, water
contamination and lengthy periods of time in service.
Lubrication plays a vital role in supporting optimal steam turbine
performance. Selecting an inadequate lubricant can have expensive
consequences, including unexpected shutdowns and high labour
costs associated with frequent cleaning and filtering of lubrication
systems and inspections of journal bearings.

46 | P a g e
 ➢ Selection Criteria:
A steam turbine oil’s most important functions are to:
• Lubricate bearings, both journal and thrust. Depending on the
type of installation, this also may include the hydraulic control
system, oil shaft seals, gears and flexible couplings.
• Provide efficient cooling.
• Prevent sludge, rust and corrosion while in service.
• Maintenance professionals need to evaluate and monitor
several integral properties of their steam turbine oil to achieve
these optimal performance characteristics. Some of these
attributes include viscosity, viscosity index, foam resistance,
rust and corrosion prevention and oxidation stability.
➢ Uses:
• Lubrication and cooling of turbine and generator bearings
• Metallic debris flush out from bearings.
• Supply of Control Oil to Governing and Protection System
• Supply of Control Oil to LP Bypass Governing.

Fig: Steam Turbine lubes oil system

47 | P a g e
 8. ELECTRICAL SYSTEMS

The generator coupled to Turbine through reduction gear

generates 11KV power which is given to 132 KV switch yard via
set-up transformer where the 11 KV is being stepped up into 132
KV.
There is tapping of 11 KV which is given to UAT (unit auxiliary
transformer) where 11KV is stepped down to 6.6 KV
This 6.6 KV is required to run the 8 no of BFP. Again 6.6 KV is
being stepped down to 415 Volt in VFD (variable frequency
drive). VFD is used to operate the ACC fans.
6.6 KV is also stepped down to 415 Volt in station transformer.
Station transformer is used for CEP, Battery charge, HRSG MCC,
STG MCC, Emergency MCC and HVAC MCC.

From station transformer 415 volt is stepped down to 220 Volt

in lightning transformer.

• Generator:
In electricity generation, a generator is a device that converts
motive power (mechanical energy) into electric power for use in
an external circuit. Sources of mechanical energy include steam
turbines, gas turbines, water turbines, internal combustion
engines, wind turbines and even hand cranks.

48 | P a g e
 • Switch Yard:
Before electricity is consumed, three steps are followed:
production, transmission and distribution. In the first, the
generator produces the electricity from a primary energy source.
The transmission step consists of moving the electricity produces
at generating stations to consumption locations. Thereafter, the
electricity must be distributed to each house, factory or business.
Electricity generated by the generators flows to transformers that
step up the voltage in preparation for travel over long distances.
The most powerful generating stations are more than one thousand
kilometers from major consumption centers. Electricity travels
more easily at high voltage because there are fewer energy losses.

Towers are the most visible pieces of equipment in the electricity

transmission chain. The high voltage conductors on the towers are
made of aluminium a lightweight material and very good
conductor offering a better price-quality ratio than other metals
such as silver, gold or copper. Each conductor is stranded with
wires twisted together around a steel core that gives the conductor
its required strength.

Fig: Switch Yard of NEEPCO (AgGBPS)

49 | P a g e
 • Transformer:
A transformer is a static electrical device that transfers energy by
inductive coupling between its winding circuits. A varying
current in the primary winding creates a varying magnetic flux in
the transformers core and thus a varying magnetic flux through
the secondary winding. This varying magnetic flux induces a
varying electromotive force (EMF) or voltage in the secondary
winding. Transformers are essential for the transmission,
distribution and utilization of electrical. As an essential element
of all nuclear, thermal or hydraulic power stations. generator
transformers are step-up transformers with delta connected LV
windings energized by the generator

voltage, while star connected HV windings are connected to the

transmission lines. Constantly, faced with voltage changes either
due to load rejection or switching operations, followed by
generator over excitation, it must also maintain the ability to
withstand overloads. The high rated current involved requires
absolute control of the magnetic field inside the tank to avoid
localized overheating of associated metallic parts. Transformers
are used to increase voltage before transmitting electrical energy
over long distances through wires. Wires have resistance which
loses energy through joule heating at a rate corresponding to
square of the current. By transforming power to higher voltage
transformers enable economical transmission of power and
distribution. Consequently, transformers have shaped the
electricity supply industry, permitting generation to be located
remotely from points of demand. All but a tiny fraction of the
worlds electrical power has passed through a series of
transformers by the time it reaches the consumer

50 | P a g e
 Fig: Transformer of AgGBPS

• Bus Duct:
In electrical power distribution, a bus duct is sheet metal duct
containing either copper or aluminium busbar for the purpose of
containing a substantial current of electricity. It is an alternative
means of conducting electricity to power cables or cables bus

• The Unit Auxiliary Transformers (UAT):

The Unit Auxiliary Transformers is the power Transformer that
provides power to the auxiliary equipment of a power generating
station during its normal operation. This transformer is connected
directly to the generator output by the tap of the isolated phase bus
duct and thus becomes cheapest source of power to the generating
station.
51 | P a g e
 • Emergency Diesel Generator (EDG):
An Emergency Diesel Generator is the combination of a diesel
engine with an electric generator to generate electric energy. This
is a specific case of engine generator. Diesel generating sets are
used in places without connection to power grid, or as emergency
power-supply if the grid fails as well as for more complex
applications such as peak looping, grid support and export to the
power grid.

• Lightening Arrestor (LA):

Lightening arrestors are the Instrument that are used in the
incoming feeders so that to prevent the high voltage entering the
main station. This high voltage is very dangerous to the
Instruments used in the substation. Even the Instruments are very
costly, so to prevent any damage lightening arrestors are used. The
lightening arrestors do not let the lightening to fall on the station.
If some lightening occurs the arrestors pull the lightening and
ground it to the earth. In any substation the main important is of
protection which is firstly done by these lightening arrestors. The
lightening arrestors are grounded to the earth so that it can pull the
lightening to the ground. The lightening arrestor works with an
angle of 30 to 45 making a cone.

• Isolator:
Isolator is a manually operated mechanical switch which separates
a part of the Electrical power. Its main purpose is to isolate one
portion of the circuit from the other and is not intended to be
opened while current is flowing in the line. Isolator are generally
used on both ends of the breaker so that repair or replacement of
circuit breaker can be done without any danger.

52 | P a g e
 • Current Transformer (CT):
Current transformers are basically used to take the readings of the
currents entering the substation. This transformer steps down the
current from 800 amps to 1 amp. This is done because we have no
instrument for measuring of such a large current. The main use of
this transformer is
1. Distance Protection
2. Backup Protection
3. Measurement

• Potential Transformer:
There are two Potential Transformers (PT) used in the bus
connected both side of the bus The potential transformer uses a
bus isolator to protect itself. The main use of this transformer is to
measure the voltage through the bus. This is done so as to get the
detail information of the voltage passing through the bus to the
instrument. There are two main parts in it
1. Measurement
2. Protection

• Bus Bar:
The bus is a line in which the incoming feeders come into and get
into the instruments for further step up or step down. The first bus
is cd for putting the incoming feeders in la single line. There may
be double line in the bus so that if any fault occurs in the one the
other can still have the current and the supply will not stop. The
two Lines in the bus are separated by a little distance by a
conductor having a connector between them. This is so that one
can work at a time and the other works only if the first is having
any fault.

53 | P a g e
 Specification of Different Machineries

GENERATORS:

MVA 28.9
Gen volt: 11 KV; PF: 0.8
1 Gas Turbine Generator No. of poles: 02 04 nos.
Ratted speed: 3000 rpm
Make: Alstom
Model: T-600
Site rating: 21 MW
Make: TDPS, standard .IS4712
2001
MVA Rating: 32.5 MVA
2 Steam Turbine Generator No. of poles: 4 02 nos.
Speed: 1500 rpm

MECHANICAL RATINGS:
1 Gas Turbine Model: G 5371 (PA)
No of shafts:1 04 nos.
Shaft Rotation: Counter
Clockwise
Make: GE

2 Auxiliary Gear of GTG Type: A519 Special 04 nos.

3 HRSG Make: Thermax LTD 04 nos.

Boiler Main Fuel: Exhaust Gas
Max working/Design Pressure:
78 (HP) and 9 (LP) Boiler rating

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55 | P a g e
 9. CONCLUSION

AgGBPS is a combined cycle power plant which

produces power by utilizing the exhaust of the gas turbine
generators to run the steam turbine generators.

One speciality of this plant is that it is capable of black start

i.e., even if there is no power in the entire north east region,
it is able to run the plant through the use of DG (Diesel
Generator).

• Vision:

To be a leading integrated Electric Power Company of the

country with a strong environment conscience.

• Mission:
To harness the huge power potential of the country, from
conventional and non- conventional sources, with minimal
impact on the environment through a planned development
of power generation projects by an integrated approach
covering all aspects of investigation, planning, design
construction, operation and maintenance of power projects,
which in turn would effectively promote the development
of the nation as a whole.

56 | P a g e
 10. SAFETY PRECAUTIONS

➢ All personnel must wear the correct protective

clothing. All personnel must avoid contact with
turbine casing, valve bodies, drains and gas lines,
which could result in serious burns.

➢ Do not wear loose clothing, neckties, etc. near rotating

machinery.

➢ All personnel should develop safety awareness.

➢ All personnel are to wear correct ear protection when

working in the vicinity of the turbines.

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 11. REFERENCES

➢ North Eastern Electric Power Corporation Limited | Home

(neepco.co.in)
➢ https://neepco.co.in/photogallerymore/1626
➢ https://neepco.co.in/power-generation/thermal-
power/agartala-gas-based- power-station
➢ https://en.wikipedia.org/wiki/Steam_turbine
➢ https://petrotechinc.com/how-does-a-steam-turbine-work/
➢ https://en.wikipedia.org/wiki/Gas_turbine
➢ https://www.energy.gov/fecm/how-gas-turbine-power-
plants-
work#:~:text=As%20hot%20combustion%20gas%20ex
pands,a%20gener
ator%20to%20produce%20electricity.
➢ https://blog.softinway.com/gas-turbine-lubrication-systems/
➢ https://www.coalhandlingplants.com/turbine-lube-oil-
system-in-thermal- power-plant/
➢ https://www.britannica.com/technology/transformer-electronics
➢ Power Plant Engineering Book
➢ Site Engineers
➢ Practical Knowledge

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