combine cycle diesel power plant

NAME: JAWAD ALI.
REG #: BSET01111037
SEMESTER: 6TH.
TECHNOLOGY: ELECTRICAL.
INDUSTRY: HUBCO POWER PLANT NWL.
DEPARTMENT OF TECHNOLOGY.
THE UNIVERSITY OF LAHORE.

DEDICATION
I dedicate this internship report to my parents. Because of
their prayers and encouragement I have been able to
complete this report.
Praise is to Allah, the most Gracious and Merciful,
who blessed me with the knowledge and wisdom and
enabled me to overcome this task. Heartiest gratitude to my
parents without their continuous encouragement and love I
could not have accomplished this task.

PREFACE :
Internship is the one step of a technical student's academic career. For a student of
the Department of Technology industrial training is essential to complete
understanding of the concepts, learned from formal education. There remains a huge
gap between academic learning and the implementation of that hypothetical
knowledge in the practical world of modern technology. Internship can compensate
this wide gap as it brings opportunities for a student to comprehend the main trends
of technology activities.
In compiling this report, I have intended to provide a synthesis of theoretical
approaches and methods of implementing them in the world of technology. I have
tried to discover the relationship between theoretical and practical type of knowledge.
I have tried to bridge the gap between theoretical assumptions and practical
necessities. During the entire course of our academic study we remain engaged in
theoretical learning where the primary objective is academic success. A concise
knowledge of the modern technology can only be attained through the pragmatic
implementation of hypothetical ideas, which we learn from our academic activities.
With these objectives, I have made all possible efforts and the necessary investigations
to submit this paper in an enlightened form in a very short time. I have tried my level
best to eliminate errors from the paper. As I had to complete my internship within a
short period of time so the study admits its limitations.
I visited the HUBCO POWER PLANT NAROWAL of Pakistan as a part of the
internship program undertaken by the Department of Technology starting from 16
June 2014 to 08 August 2014 (8 Weeks).
Sincerely
( JAWAD ALI )
BSET 01111037
Department of Technology (Electrical)
The University of Lahore.

ABSTRACT
This report contains the details of how power plant is operated, it’s
machinery as well as description of them.
The first work is the verification and collection of the data of
important electric equipment’s and system in power plant. This also
includes the operation, devices used for the protecting and
controlling devices used for the system.
This report describes my experience and suggestions which I want to
give to HUBCO Power Plant Narowal.

TABLE OF CONTENT
1) Introduction of organization(Past, Present, Future).................. 1
2) Organization Chart.................................................................. 3
2) Departments of the Organization............................................ 4
3) Project Area of Training…....................................................... 7
4) Schedule of Internship........................................................... 16
5) Major Equipment’s Name Plate Data...................................... 18
6) Operation…………………………………………………………………
7) STG OPERATION……………………………………………………….
8) Engine Operation……………………………………………………….
9) Switchyard Instrument………………………………………………..
10) Power Transformer……………………………………………………
11) Alternator Protection Equipment………………………………….
12) Skills and Technique............................................................. 44
13) Role/Responsibilities of Internee.............................................45
14) Useful Points For new Internees........................................... 48
15) Suggestions........................................................................... 50
16) Conclusion............................................................................ 51

TNB REMACO PAKISTAN (PVT) LTD.
HUBCO POWER PLANT.
225MW COMBINED CYCLE DIESEL
HUBCO POWER PLANT NAROWAL.
INTODUCTION OF THE PLANT:
HUBCO Power plant Narowal Construction work began in 2008 and completed in
2010. The plant achieved its COD on 22 April 2011.The plant entered into an
Equipment Supply Contract (ESC) with MAN Diesel & Turbo, Germany and
Construction Contract (CC) with MAN Diesel Pakistan (Pvt) Ltd in April 2008
collectively called Engineering, Procurement and Construction (EPC) Contract.
The Owners Engineers were Mott MacDonald, Ireland.The O&M Contractor are
TNB Remaco Pakistan (Pvt) Ltd a subsidiary of TNB Repair and Maintenance Sdn.
Bhd, Malaysia. Narowal is a combine cycle power plant with net output of 214 MW.

It consists of 11 diesel engines of 18.4 MW net output each plus a steam turbine of
16 MW. The fuel used is High Sulpher Furnace Oil (HSFO) supplied by Bakri
Trading Company Pakistan (Pvt) Ltd.
PROJECT BRIEF
Gross Capacity at ISO 225MW
Plant Output (Net) 215MW
Technology MAN Engines (18.4MW each)+1 Steam
turbine(16 MW) Combine Cycle
Term of Agreement 15 year
Net Efficiency
50%
(Life Cycle)
Customer WAPDA GAPCO
Construction Start Date April,2008
Fuel provided by Bakari Trading Company (PVT) LTD.
VISION, MISSION
Vision Statement
Enlighten the future through excellence, commitment, integrity and honesty.
Mission Statement
To become leading power producer with synergy of corporate culture and values that
respect community and all other stakeholders.
Quality Policy
We work together as a team for implementation and continual improvement of total
quality system in order to achieve satisfaction of our internal and external customers.
The Hub power station was one of the first and largest Independent
Power Producer (IPP) in Pakistan to be financed by the private sector
in Southern Asia .The Hubco Narowal Power Plant (HNPP) has been
constructed on 62 acres of land, 5 km off the Narowal Muridke Road,
15 km from Narowal and about 150 km North East of Lahore.
HUBCO Narowal Power Plant (HNPP) comprises of 11 generating
sets based on MAN 18V48/60 Engine(It means 18 cylinders V-type

each with 48 cm diameter of cylinder and 60 is length of strock.), 11
Alborg Heat Recovery Steam Generators and one air cooled
condensing Steam Turbine from Dresser Rand .
Each engine has generating capacity of 18.9 MW while the
designed output of the Steam Turbine is 16.45 MW Interconnection
with the NTDC system is via a 132 KV Switchyard of
HNPP having 4 overhead outgoing bays. The power is dispersed
to NTDC grid system through:
 Narowal Grid Station (12 km transmission)
 Baddomalhi – Narowal 132 kV circuit (2 km line)
The Operations and Maintenance (O&M) of HNPP is contracted out
to Tenaga National Berhad Repair and Maintenance Company (TNB
REMACO) for a period of 5 years.
The Fuel Supply Agreement has been executed with Bakri
Trading Company Pakistan (Pvt) Limited for a period of 25
years. The Complex has the storage capacity of 30 days of fuel
consumption at full dispatch level.

ORGANIZATION CHART
DEPARTMENTS OF ORGANIZATION
There are many departments in HUBCO Power Plant.
The Main Departments Are .
 MANAGEMENT DEPARTMENT
1. H.R Department
Human resources is the set of individuals who make up the workforce of
an organization, business sector, or economy.
The HR Department of Century also conductsinterviews, training programs.

2. Finance Department
The Finance department is responsible for organizing the financial and
accounting affairs including the preparation and presentation of proper
accounts, and the provision of financial information for managers. The main
areas covered by the financial department include; book keeping procedures,
providing management information, management of wages and raising of
finance.
 TECHNICAL DEPARTMENT
Technical Department Consist of Mechanical, Electrical , Decanting
and Chemical Departments.
1. Electrical
This department is responsible of all electrical ,maintenance all electrical
equipment’sand also observers whole electrical system like switch yard and
generators speed, powerfactor, winding temperature etc.Electrical have two
sub departmentone is called Electrical maintenance and other one is called
electrical operation department.
2. Mechanical
This departments is responsible of all the mechanical work in HUBCO to
check the vibration of Engine and also observers whole mechanical system
like working of engine, observe temperature of engine linear, header and also
do the daily or routine maintenance mechanical department control of boiler
etc. Mechanical have also two sub department one is called mechanical
maintenance and other one is called mechanical operation department.
3. Chemical
This departments is responsible of all the chemical work in HUBCO to check
the TDS in HT or LT water and check Sulpher in HFO also check dielectric
strength of transformer oil.
4. Decanting
In HUBCO Power Plant this heavy fuel oil (HFO) (LFO) and Lube Oil is
treated through different process to make it useful for the engine to generate
the electricity. This process called DECANTING PROCESS. Heavy fuel oil

(HFO) after suction from tanker in decanting station goes to the storage tanks
for storage.
 FIRE FIGHTING DEPARTMENT
A fire department provide "fire protection" or fire prevention services, and
give fire safety advice and fit smoke alarms for members of the Industry. In
HUBCO F.F Department gives training to all their employs and trainees how to
react in the emergency and how to protect the fire victim area from fire.
 HEALTH DEPARTMENT
This department gives medical facilities and first aid in case of any accident.
NAME PLATE DATA OF EQUIPMENTS:
Alternator used with Diesel Engine:
Alternator used with Steam Turbine :

Where volume in cubic meter, Pressure in bar and Temperature in centigrade.
STEAM TURBINE:

OPERATION:
There are 11 marine engine (18V/48/60B) rotate 11 generators, giving 18.9 MW
each. An engine uses HFO as a fuel. After it uses HFO, its exhaust is of so high
temperature that it can be used to convert water to steam. Exhaust converts the water
into steam by Heat Recovery Steam Generation HRSG. This steam is then used to
drive steam turbine which provides 16.2 MW. HRSG makes this process, combine
cycle, hence called combine cycle diesel power plant.
Principle of engine
An engine is a mechanical device which acts as a prime mover to
rotate the rooter of alternator to generate the electricity. It works on
the principle of 4-strocks in which 4-strocks take place in each
cylinder one after another .these 4-strocks are:
 Intake Stroke
 Compression Stroke
 Power Stroke (combustion)
 Exhausts Stroke
MAIN COMPONENT OF ENGINE
There are many component of engine which are following:
i. LINER
Such a component of engine which is cylindrical cone in shape. Piston moves in it
vertically. It is covered by head.
ii. HEAD

Such a component of engine in which intakes and exhausting valves open and close.
It covers the liner. This head is made of cost iron.
iii. PISTON
Such a component which sucks the air and compressed it. This piston helps in
combustion process.
There are three part of piston which is given bellow:
 Crown
 Skirt
 Piston rings
Types No
Compression ring 2
Oil compression rings 1
iv. CRANK SHAFT
Such a shaft which derived by cam shaft through rocker arms head valve pistons etc.
crank shaft is coupled with the alternator shaft and provide the mechanical energy of
alternator shaft.
v. CAM SHAFT
Such a shaft which is provide the mechanical power of rocker arm by push rods is
called cam shaft. It is moved by crank shaft with the help of gear.
vi. HEAD VALVES
Such a component which moves back and forth and cause.The
intakes the fresh air and exhausting of heat through head opening.
There are two types of valves:
 Intakes valves
 Exhausting valves
vii. ROCKER ARMS
Rocker arms located at upper side of engine, with
its two arms .One side of each arm attached with
cam shaft through pushing rods other sides
attached with head valves. When cam shaft moves
rocker arm attached with it also move and on the

other side of rocker arm head valves which are attached on that side also move up
and down .In the result of opening the hole of head and intake air and exhaust the
heat possible.
viii. COUNTER WEIGHT
It is installed on crank shaft .When
piston hits the crank shaft and it rotates
then counter weight helps in this
rotation of crank shaft also spot it.
ix. MAIN BEARING
It is installed on the crank shaft. They provide the spot, control the vibration and
move the crank shaft smoothly main bearing protect the shaft from damaging.
x. FLY WHEEL
Fly wheel are inserted at the end of
crank shaft in between engine and
alternator .it is a main part of engine
which rotates the crank shaft by
storing power during first stock and
provides it to the crank shaft in
remaining the three stroke. It is very
heavy in weight so it provides the inertia from rotation of crank shaft.
xi. TURBO CHARGER
Turbo charger instead on the front of engine speed of
T.C is 19000 rpm. It performs two functions.
It sucks the fresh air from atmosphere and compress it
.After compressing the air turbo charger sends it to the
engine for combustion.
It exhausts the heat which produces during the
combustion.
xii. CHARGE AIR COOLER
Charge air cooler is used to
maintain the temperature of
compressed air before

sending it to the engine for the combustion air coming out of turbo charger has very
high temperature then required for the combustion in the engine. That why we
installed charge air cooler to reduce the temperature to a useable value .it is located
under the turbo charger.
xiii. FUEL SUCTION PUMP
A suction pump is installed near the every liner of engine it sucks the HFO from the
pipe lining which is supplying HFO to the engine and sends it to fuel injector. Then
sprays this HFO on the piston in the liner for combustion in the form of sprinkles
from fuel injector.
KEY SYSTEMS
The key systems of the plant include:
 Fuel System
 Air System
 Cooling System of Engine
 Lubrication System of Engine
 Steam Handling System
 Power System
 Dispatch System
 Control Room
These systems help to maintain the engines which drive the alternator which in
return produce electricity. We will discuss these systems one by one.
 FUEL SYSTEM
In HUBCO Power plant we are using heavy fuel oil (HFO) as a fuel for production
of electricity. This heavy fuel oil (HFO) is treated through different process to make
it useful for the engine to generate the electricity. These process are given bellow:
 FUEL DECANTING PROCESS
 STORAGE OF FUEL
 FUEL TREATMENT HOUSE

1. FUEL DECANTING PROCESS
In Decanting station pumps using to unload fuel.These pumps drived by induction
motor which sucks the heavy fuel oil (HFO) from tanker through a filter and valves.
These are 8 in numbers which is installed in decanting station.
And these pumps transfer HFO in main Tank…
2. STORAGE OF FUEL
The storage tanks are Different types which are given bellow:
I. Main Tank
II. Buffer Tank
III. Day Tank
IV. Lube Oil Tank
V. Sludge Tank
VI. Oily Water Tank
Heavy fuel oil (HFO) is stored in Main Tank after suction from decanting process.
Buffer tank need of our daily requirement heavy fuel oil (HFO) is pumped from
main tank to buffer tank through various pump with the help of valve installed in the
line.
After purification in the fuel treatment house (FTH) the purified heavy fuel oil
(HFO) goes to day tank for storage. Day tank stores the heavy fuel oil (HFO) daily
consumed by engine.
Lube oil after suction from tanker goes to lube oil tanks first storage.
Sludge tank stores the sludge coming out of HFO separator after treatment from oily
water treatment house in which oily water and sludge are separated.
Oily water tank stores the oily water coming out of oily water treatment plant and
lube oil separator.
 COOLING SYSTEM OF ENGINE
It consists of LT water, HT water and the row water. LT and HT water are
actually the same form of water moving in the engine in a close cycle from heat
exchanger to the back that the heat exchanged but the only difference between LT
and HT is that of temperature value so called the low temperature and the high
temperature.

1. LT Water
With heat exchanger, the LT water start moving with its initial temperature range to
420 C to 480 C. It goes to charge the air cooler first to maintain the temperature of the
compressed air to useable value. From charged air cooler, LT water moves to the
lube oil cooler to cool down the lube oil to make it workable when this LT water
comes out of the lube oil cooler. Its temperature crosses the value of 500 C which is
the limiting value of LT Water. This water now becomes High temperature with
temperature about 590 C.
2. HT Water
It is the water coming out of the lube oil cooler with the temperature of 590 C.
Initially as it moves in the internal part of the engine, the temperature goes on
increasing. Before entering the liner of the engine, its temperature is 800 C to 840 C.
In liner, it keeps the temperature of the liner walls to a limited value. It also saves the
liner walls from expanding which occur often because of increase in temperature.
After coming out of the liner, HT water has temperature of 900 C to 950 C. This high
temperature water goes to heat exchanger where it exchanges the heat with row
water and again becomes the LT water and the cycle continues.
3. Raw Water
It absorbs the heat in the heat exchanger and its temperature increases to some
extent. After this, it goes to cooling water for cooling purpose.
4. COOLING TOWER
It is the part of engine cooling system where raw water is cooled. A cooling tower is
basically a closed room in which fans and sprinkles are installed.The raw water
moves in spiral pipes on which sprinkles are sprinkling the water to cool the raw
water. The raw water is cooled which is pumped down to heat exchanger. The
sprinkled water is again pumped to the sprinkled pipes which are sprinkling. The air
fans collect the stream from cooling tower and exhaust to atmosphere. These fans are
driven by induction motors
 LUBRICATION SYSTEM
Lube oil from main tank is pumped to the engine for the cooling and lubricating
purpose in the engine. The temperature of lube oil increases so we send it to the heat
exchanger through pumps. In heat exchanger the high temperatures lube oil it
exchanges its heat with raw water and becomes cool. After exchanging heat the cool
lube oil passes through auto filter section. Where it filtered and then sends it to
engine.

Switch Yard System.
COMPONENTS OF SWITCHYARD
Basic electrical components available in Switchyard are: Power Transformer,
Reactors, Instrument Transformers (Current and Voltage/Potential Transformer),
Disconnect Switches, Bushings, Surge Arresters, Standoff Insulators and earth
switches. Some of these components look alike and hence are sometimes misused for
one another, effect of which is catastrophic to the equipment, the entire electrical
network and to the personnel. This is applicable to Standoff Insulators, Lightning
Arresters and Bushings, but each of them possess unique characteristic, which this
paper will expatiate. In view of this, discussion will be limited to these three
components, and the station Operator and Infrared thermographs who have limited
substation experience will be able to differentiate among these components. Each
components located in the Switchyard.
1. MV ROOM
Many medium voltage (MV) indoor switchgear rooms exist worldwide. The
complexity of these rooms varies considerably depending on location, function and
technology adopted by the owner.
2. CONTROL ROOM
Control Room is actually a place which monitors and controls boilers, turbine,
engine, alternator, transformer and switch yard, every part and components of the
thermal power plant or any other plant. Different types of control panels and feeders
are installed in the control room for a s a whole and individually control of the
components of plants. In HUBCO control 11 control panels for 11 engines and the
generators in turn. 7 Panels are installed for DC supply to the control room. 4 panels
are installed for 4 power supply lines. 1 for KALA SHAH KAKO and 3 for
NAROWAL. All this system is PLC based and controlled automatically by high
technology computers and software. The control system performs following
operations.
 Maintains safe and efficient boiler operation.
 Monitors plant operational and emission data detects and responds to the
changing conditions with the regard to the maximizing plant safety and
efficiency.
 Overseas the operation of plant equipment and dispatch operators for local
maintaining for safe operation.

 Works with maintenance to troubleshoot the problems and ascertains possible
cause.
 Read meters and gauges or automatic recording devices at specified intervals
to verify operating conditions.
 Record data such as temperature of equipment, hours of operation, fuel
consumed, temperature or pressure, water level, analysis of fuel gases, voltage
load and generator balance.
STARTING AIR SYSTEM:
Staring air is necessary for the staring of engine initially. For this
purpose there is a proper system, which provides compressed air.
This system is called starting air system. According to this system
the fresh air is taken from the environment and compressed to
required pressure. This process takes place in the compressor room
where the fresh air is sucked from the environment and sent to the
compressors. Where it is compressed to 25-30 bar of pressure. This
compressed air is then sent to the engine where it is provided to the
liner of engine. It accumulates at the bottom of every liner of engine
and provides initial push to the piston in upward direction. When the
engine gain the speed of about 120 rpm. The starting air supply is
interrupted and working air supply is switched on which takes the
engine to full speed e.g. 500rpm.
WORKING OF ENGINE
In engine, the main part is crank shaft which rotates itself, the other parts of the
engine and the alternator itself. As the crank shaft moves, it also moves the cam shaft
through push rod. Cam shaft on the other hand moves the head valves up and down.
As the head valve moves up and down, the intake of air and exhaust of gases occur
through the opening of the head. The air intake causes the combustion of the fuel by
up and down movement of the piston. The piston is connected to the crank shaft. By
this up and down movement of piston, the crank shaft rotates about its axis. The
crank shaft in turn rotates the cam shaft and this process continues. As mentioned
above, the crank shaft is also coupled with the rotor of the alternator through the fly
wheel. 100 rotations of the crank shaft cause the rotation of the rotor of the alternator
which in turn produces the electricity.

Alternator
Such a machine which converts a mechanical energy into electrical
energy is called generator.
In HUBCO, 12 Alternators, 11 have connection type Ү, output power
23035KVA, 15KV, 500rpm, power factor 0.8, current 887amp, salient
pole. Excitation system pilot 131vdc, 11.3Adc.
One Alternator ABB, connection type Ү, output power 18428KVA,
15KV, 1500rpm, power factor 0.8, current 703amp, salient pole.
Excitation system pilot 123vdc, 10Adc.
STEAM HANDELING SYSTEM
This system of steam handling refers to the production of steam in the boiler and
then utilization
Of this steam in the turbine for production of electricity. The exhaust coming out of
turbo charger of eleven engines goes to their respective boiler unit for conversion
into steam. In boiler the heat (exhaust) coming out of engines with temperature
about 400 -450 degree to steam after passing through different components of boiler.
1. Boiler Unit
Boiler is consisted of 4 parts named as LP evaporator. Economizer, HP evaporator
and super heater. It is the boiler unit where actually the conversion of heat into steam
takes place. The exhaust coming out of engine goes to the LP evaporator. At this
stage it is to be noted that the boiler being used in HUBCO are water tube boiler in
which water circulates in tubes heat is surrounding these tubes inside the boiler. This
water is provided by boiler feed water tank, from the LP evaporator. The water in
tube goes to economizer converts the water in tube into unsaturated steam. This
unsaturated steam gains its proper value in HP evaporator unit where the actual
unsaturated steam is produced. From HP evaporator this unsaturated steam drum
inserted above the every boiler unit. This stream drum is partially filled with water
and partially with unsaturated steam. The stream drum the moisture in the
unsaturated steam is absorbed in water to some extent.
This unsaturated steam not completely steam not completely dried goes to super
heater for drying purpose. Now the stream coming out of super heater is pure steam
and this steam is sent to steam header. The steam header is the storage tank where
steam tank where steam coming out of boiler is stared and then fed to steam turbine.

2. Steam Turbine
Stream turbine being used in HUBCO is impulse steam turbine in which the
steam is passed through nozzle before hitting the rotor plates. The steam injecting
out of nozzle has much velocity and pressure. It then hits the plates of rotor of
turbine and causes its rotation. This rotor is coupled with generator through shaft and
causes the rotation of rotor of generator which gives electricity in turn the normal
running speed of steam turbine rotor is 6000 rpm. The output speed is 1500rpm. The
tripping speed is 6871/7177rpm. The power output of stream turbine is 16MW. The
steam inlet pressure of steam turbine is 15Bar and the exhaust pressure is 0.01Bar.
the steam inlet temperature of steam turbine is 350 degree.
Black Start Generator
If all of the plant’s main generators are shut down, To provide a
black start, power stations have small diesel generators, normally
called the Black Start Diesel Generator (BSDG).
Type Sab 901 Year 2008 Rated power 375KVA
Max Ambient 20 0C P.f 0.8 Frequency 50Hz
Voltage 400V Current 541A Speed 1500rpm
Performance class 82
LUBE OIL SYSTEM:
Lubricating oil ( Lube Oil ) of a Diesel Engine achieves two objectives:
It must cool and lubricate.
Among the other benefits yielded are
 Reduced maintenance costs
 Maximized Engine life
 Maximized power output
 Low oil consumption.
Lube oil perform a number of important functions in the Diesel
Engine:

 Wear reduction of components such as bearings, pistons, piston
rings and cylinder liners .
 Reduction of Friction .
 Cooling of Piston .
 Corrosion prevention due to acids and moisture.
 Cleaning pistons and preventing sludge build-up on internal
surfaces.
 Keeping seals lubricated and controlling swelling to prevent
leakage due to seal failure.
Engine lube Oil consist of
 Base Oil (typically75 - 83%)
 Viscosity Modifier (5 - 8%)
 Additive Package (12 - 18%)
As the base oil alone cannot provide all of the lubricating oil
functions required in modern engines, the additive package has
evolved to play an increasingly important role in the oil lubrication.
The bellow Diagram describes the supply and storage of the lube Oil
in Power Plant. Lube oil after suction from tanker goes to lube oil
tanksfor storage and then circulated and filter for each eleven Engine
in Plant. LO SEPARATOR UNIT is used for the Circulation and
purification of the Lube Oil.

In a 4 stroke Diesel Engine the Lube Oil is supplied to the main bearings through
drillings in the engine frame to the crankshaft main bearings. Drillings in the
crankshaft then take the oil to the crankpin or bottom end bearings. The oil is then
led up the connecting rod to the piston or gudgeon pin and from there to the piston
cooling before returning to the crankcase.
Oil is also supplied to lubricate the rocker gear operating the inlet and
exhaust valves and to the camshaft & camshaft drive.
 The oil then drains from the crankcase into the drain tank or sump.
 The oil in the drain tank is being constantly circulated through a centrifugal
purifier. This is to remove any water and products of combustion plus any
foreign particles which may be in the oil.
 The cylinder liner must be lubricated as well. This is so there will be a film of
oil between the piston rings and the liner and also so that any acid produced
by combustion of the fuel is neutralized by the oil and does not cause
corrosion. The oil is led through drillings onto the liner surface where grooves
distribute it circumferentially around the liner, and the piston rings spread it
up and down the surface of the liner.

The below Diagram illustrate the Circulation of the Lube oil
The below Diagram explains the Lube Oil cooling Tower

EXAUST GAS SYSTEM :
In Exhaust gas heat recovery system exhaust gases of the internal combustion
diesel engine are utilized to generate steam which is used for driving a turbine for
an electric generator and the steam for miscellaneous uses in the Plant.
Four Basic HRSG Boiler Components
• Super heaters (gas to dry steam heat exchanger)
Super heater is one of HRSG components that serves to raise temperature of
saturated steam to be superheated steam.
Superheated steam when used to perform work by way of expansion in the turbine
will not condense, thus reducing the possibility of danger which is caused by back
stroke caused by steam that condenses yet in time, so it will cause vacuum in undue
area of expansion.

• Evaporators (gas to wet steam heat exchanger)
Evaporator is one of HRSG components which serve to convert water into saturated
steam. Evaporator will heat water that falls from steam drum which still in liquid
phase to form the saturated steam so it can be forwarded to super heater.
• Economizers (gas to water heat exchanger)
Economizer serves to heat feed water before it enters steam drum and evaporator.
Furthermore the evaporation process can be easier by using high temperature flue
gas of HRSG so increase the efficiency of HRSG because it can reduce heat loss in
the Heat Recovery Steam Generator (HRSG). Water which enters evaporator is at
high temperature so evaporator pipes are not easily damaged due to difference in
temperature is not too high.

• Preheaters (gas to water heat exchanger)
Pre heater is one of HRSG components that serves as initial heater of water which is
pumped from condenser before enter into feed water tanks. In the HRSG system,
preheater serves to raise temperature before enter feed water tanks which later will
be forwarded to economizer.
The Diagram of the Boiler illustrate the different Temperature ranges in
the different regions of the Boiler.
COOLING SYSTEM :
The below Diagram describes the Cooling Water Supply.

The below Diagram describes the supply of Charge Air Cooling Water.

The below diagram describes the Cooling of the Nozzle.
The below diagram describes the cooling of the lube oil.

WATER TREATMENT PLANT (WTP):
Reverse osmosis (RO) is a water purification technology that uses a
semipermeable membrane. This membrane technology is not properly a filtration
method.
In reverse osmosis, an applied pressure is used to overcome osmotic pressure, a
colligative property, that is driven by chemical potential, a thermodynamic
parameter.
Reverse osmosis can remove many types of molecules and ions from solutions, and
is used in both industrial processes and the production of potable water. The
result is that the solute is retained on the pressurized side of the membrane and the
pure solvent is allowed to pass to the other side. To be "selective", this membrane
should not allow large molecules or ions through the pores (holes), but should allow
smaller components of the solution (such as the solvent) to pass freely.

Basic components of Reverse Osmosis System :
1. Cold Water Line Valve:Valve that fits onto the cold water supply line. The
valve has a tube that attaches to the inlet side of the RO pre filter. This is the water
source for the RO system.
2. Pre-Filter (s): Water from the cold water supply line enters the Reverse
Osmosis Pre Filter first. There may be more than one pre-filter used in a Reverse
Osmosis system. The most commonly used pre-filters are sediment filters. These are
used to remove sand silt, dirt and other sediment. Additionally, carbon filters may be
used to remove chlorine, which can have a negative effect on TFC (thin film
composite) & TFM (thin film material) membranes. Carbon pre filters are not used if
the RO system contains a CTA (cellulose tri-acetate) membrane.
3. Reverse Osmosis Membrane: The Reverse Osmosis Membrane is the heart of
the system. The most commonly used is a spiral wound of which there are two
options: the CTA (cellulose tri-acetate), which is chlorine tolerant, and the
TFC/TFM (thin film composite/material), which is not chlorine tolerant.
4. Post filter (s): After the water leaves the RO storage tank, but before going to
the RO faucet, the product water goes through the post filter (s). The post filter (s) is
generally carbon (either in granular or carbon block form). Any remaining tastes and
odors are removed from the product water by post filtration.
5. Automatic Shut Off Valve (SOV): To conserve water, the RO system has an
automatic shutoff valve. When the storage tank is full (this may vary based upon the
incoming water pressure) this valve stops any further water from entering the
membrane, thereby stopping water production. By shutting off the flow this valve
also stops water from flowing to the drain. Once water is drawn from the RO
drinking water faucet, the pressure in the tank drops and the shut off valves opens,
allowing water to flow to the membrane and waste water (water containing
contaminants) to flow down the drain.
6. Check Valve: A check valve is located in the outlet end of the RO membrane
housing. The check valve prevents the backward flow or product water from the RO
storage tank. A backward flow could rupture the RO membrane.
7. Flow Restrictor: Water flow through the RO membrane is regulated by a flow
control. There are many different styles of flow controls. This device maintains the

flow rate required to obtain the highest quality drinking water (based on the gallon
capacity of the membrane). It also helps maintain pressure on the inlet side of the
membrane.
8. Storage Tank: The standard RO storage tank holds up to 2.5 gallons of water. A
bladder inside the tank keeps water pressurized in the tank when it is full.

MAINTENANCE:
Operation & Maintenance (O&M) contracts cover all aspects and activities
necessary to run your power plant in a safe and most economical manner. An O&M
agreement will help you minimize your risks and maximize your profit.
Operation & Maintenance (O&M) service means that care about your assets and has
major Objectives as below mention:
nce

Benefits :
General Maintenance Periods of Systems :
1.5 k Maintenance
3 k Maintenance
18 k Maintenance
SWITCH YARD:
The three-phase power goes to SWITCH YARD where power transformers are used
to convert the generator's voltage (15 KV) up to extremely high voltages for
long distance transmission (132 KV).
Switch yard includes:

Power transformer:
A transformer is an electrical device that transfers energy between two or more
circuits through electromagnetic induction. In order to minimize the transmission
losses power transformer is used by increasing voltage up to certain level i.e 132
KV.
The two main functions of a power transformer are to transfer electrical
current from a source to a destination, and to regulate the voltage of that
current before it reaches the intended destination. This is managed in the coil
system of the device. The coils function as conductors, helping to maintain the
current flow within a range that is considered acceptable. By managing the magnetic
field fluctuation that takes place within the core of the power transformer, it is
possible to control the voltage and change it in whatever manner is necessary
before the current is delivered to houses or businesses.
The main parts of the transformer are as under :
1. Oil Tank:
This part of the transformer contains the assembly of the core and the
winding which is immersed in insulation oil.
2. Radiator :
This part is basically used for the cooling of transformer by the means of
natural air.

3. Conservator:
This is mainly used for the storage of extra insulation oil which is to
overcome the requirement of the tank assembly system.
4. Air breather:
This is used for the extraction of the moisture from the core of the
transformers.
5. Temperature meter (O.T/W.T):
These are used for taking the readings of O.T.I - Oil temperature Indicator
and W.T.I - Winding Temperature Indicator.
6. Drain Valve:
This is used for the Exhaust of the insulation oil during the maintenance of
the Transformer.
7. Tap-changer:
This is used for the tapping of the Transformer at different levels.
8. Pressure release Valve (P.R.V):
This is used for the tripping purpose in the Transformers for the safety
purpose.
9. Buchhloz Relay:
This is used for the tripping purpose by the help air gap inbetween the
switching circuit.
10. Primary and secondary winding:
These are the two coils of the Transformer and the no. of turns depend upon
the rating of the transformer.
Bus Bars :
A conductor or an assembly of conductors for collecting electric currents and
distributing them to the outer circuit.
Bus Bar Scheme
In HUBCO have double bus bar scheme,Indouble
bus bar system two identical bus bars are used in
such a way that any outgoing or incoming feeder
can be taken from any of the bus.

Bus Coupler :
Two different bus sections of two different power transformers are connected by
means of a bus coupler. The bus coupler becomes useful when one of the power
transformers fails or a fault occurs in either of the bus sections.
Insulators:
The overhead line conductors should be supported on the poles or towers in such a
way that currents from conductors do not flow to earth through supports i.e., line
conductors must be properly insulated from supports. This is achieved by securing
line conductors to supports with the help of INSULATORS.
The insulators provide necessary insulation between line conductors and supports
and thus prevent any leakage current from conductors to earth.
Circuit Breaker & Relays:
A circuit breaker is an automatically operated electrical switch designed to protect an
electrical current from damage caused by overload or short circuit. Its basic function
is to detect a fault condition and, by interrupting continuity, to immediately
discontinue electrical flow. The circuit breaker works along with the relays which
give a tripping signal in case of any irregularity or the faults. The circuit breaker then
opens to open the circuit such that other instruments of the system can be protected.
Isolators:

It is used to make sure that an electrical circuit can be completely de energized for
service or maintenance. It also allowa the isolation of the apparatus such as circuit
breakers transformers and transmission lines, for maintenance.
Current Transformers
A current transformer (CT) is a measurement device designed to provide a current in
its secondary coil proportional to the current flowing in its primary. Current
transformers are commonly used in metering and protective relaying in the electrical
power industry where they facilitate the safe measurement of large currents, often in
the presence of high voltages. The current transformer safely isolates measurement
and control circuitry from the high voltages typically present on the circuit being
measured.
Voltage transformers:
Voltage transformers (VT) or potential transformers (PT) are another type of
instrument transformer, used for metering and protection in high-voltage circuits.
They are designed to present negligible load to the supply being measured and to
have a precise voltage ratio to accurately step down high voltages so that metering
and protective relay equipment can be operated at a lower potential. Typically the
secondary of a voltage transformer is rated for 69 V or 120 V at rated primary
voltage, to match the input ratings of protection relays.
Lightning Arrester:
A lighting arrester is a piece of equipment that is designed to protect electrical
systems and components from damages that can be caused by surges of electricity.
When a surge of electricity hits an electrical system, it attempts to equalize and
dissipate itself, taking the most efficient routes. A lightning arrester provides a path
of least resistance for doing this, routing the excess electricity away from the system

and into the ground where it can dissipate without doing any harm. The lighting
resistor includes components attached to the electrical system with leads that reach
the ground.
ALTERNATOR PROTECTIONS:
 In a generating station the generator and transformer are the most expensive
equipments and hence it is desirable to employ a protective system to isolate
the faulty equipment as quickly as possible to keep the healthy section in
normal operation and to ensure uninterruptable power supply.
 The basic electrical quantities those are likely to change during abnormal fault
conditions are current, voltage, phase angle and frequency . Protective relays
utilizes one or more of these quantities to detect abnormal conditions in a
power system.
 Protective system cost is 4-5%of the total cost.
FAULT OCCUR IN GENERATOR:
Unbalanced Loading.
Unbalanced loading arises from fault to earth or faults between phases on the
circuits external to the alternator. Unbalanced current may burn the
mechanical fixing of the rotor core or damage the field winding.
Under normal operating condition, algebraic sum of three currents flowing
through the relay is zero and relay does not operate. When unbalancing
occurs, resultant current flows through the relay and relay trips the circuit
breaker to disconnect the alternator from the system.
Stator Winding Faults.
Fault between phase and ground.
Fault between phases.
Inter-turn faults involving turns of same phase winding.

Differential Protection:
It provides protection against phase to phase and phase to ground current at
two ends of the protected sections are compared. Under normal operating
conditions, these currents are equal, hence no current flows through the relay.
When a fault occurs in the protected zone, currents at two ends
of the CT becomes unequal. Differential current flowing the the
relay isolates the protected section from the system .
LIMITATION
It is impossible to provide protection to the whole winding when neutral
earthing resistance is used. It protects only 85% of the winding.
Failure of Field
The chances of field failure of alternators are undoubtedly very rare. Even if it
does occur, no immediate damage will be caused by permitting the alternator
to run without a field for a short period. In this case the alternator can be
disconnected manually. So there is no need of automatic protection.
Over-current
It occurs mainly due to partial breakdown of winding insulation or due to
overload on the supply system. Over current protection for alternator is
considered unnecessary because of the following reasons:
As the modern alternators have considerably high values of
internal impedance, these will stand a complete short circuit at
their terminals for sufficient time without serious overheating.
On the occurrence of an overload, the alternators can be
disconnected manually.
Over-speed
The chief cause of over speed is the sudden loss of all or the part of load on
the alternator. Centrifugal devices mounted on their driving shafts trip the
main valve of the prime mover when a dangerous overs peed occurs.

Over-voltage
The field excitation system of modern alternators is so designed that over
voltage conditions at normal running speed can’t occur.However, overvo ltage
in an alternator occurs when speed of prime mover increases due to sudden
loss of alternator load.Usually control governers are provided which
continuously checks the speed and prevents the over speed.
SKILL AND TECHNIQUE
I have learnt many techniques during my internship but my mostly focus was to
learn complete system of power plant. I learn different system in power plant like ,
heat recovery system, generator system, cooling system, starting and shut down
engine, fuel oil system, lube oil system, dispatch system. Control room engineer
teach us about this system.
After learn some system they give me some home assignment (presentation at
combine cycle diesel power plant and lube oil system working etc) to check my
ability of learning. I complete my all assignments with full of devotion and satisfied
my senior engineer. Basic skills are IR test, temperature sensor test which is detailed
below.
1. IR test of Alternator
The insulation resistance and polarization index tests of an electric generator has
been regarded as a useful tool in evaluating its windings for buildup of dirt or
moisture., deterioration of the insulation, fitness for high
potential tests and suitability for further operation.
The IR test measures the resistance of the electrical insulation
between the copper conductors and the core of the stator or
rotor. Ideally the value of this resistance is infinite since the
purpose of the insulation is to block current flow between the
copper and the core. But in practice, it is not possible.
However, the resistance should have a high value to avoid any
appreciable leakage current. Lower value of IR indicates that
the insulation has been deteriorated.
PI is a variation of the IR test. It is the ratio of IR measured
after voltage has been applied for 10 minutes (R
) to the IR
10
measured after one minute (R
), i.e.
1

PI = R
10
/R
1
Low value of PI indicates that the winding may have been contaminated with oil, dirt
etc or absorbed moistures. In the test, a relatively high DC voltage is applied
between the copper conductor and the stator or rotor core usually between the
winding and ground as the machine core &body is grounded).
2 TEMPERATE SENSOR TEST
Using two way to check the temperature sensors pt100 and thermocouple.Details are
given below.
1. HEATER OIL BATH
It is used to calibrate and testing
of temperature switches which are used
in industry.
TEMPERATURE SWITCH:
The figure shown below is the
temperature switch that can sense the
temperature of fluid or water or oil have
set points and consist of limit switches
that can change the contact of switch
when desire temperature achieved.
2. Process Calibrator
Temperature measurements with PT 100 elements
have proven to be very robust and reliable. These
sensors are very rarely replaced due to insufficient
calibration results.
First of all sensor heated by using oil bath, then
temperature sensor output check using process
calibrator and give signal to PLC.

RESPONSIBILITIES OF INTERNEE
 Be Punctual
 Be Civilize
 Use Good Language with all your seniors and juniors.
 Be Ethical in all your Behaviors.
 Accept and Obey the all Rule and Regulations of your organization
 Before performing any Practical First have sufficient knowledge of it.
 First Learn proper use of Tools and Equipment’s.
 Call every Tool with it Specific proper name.
 During Performing practical put all your concentration on your work.
 Wear all Safety equipment in working area e.g. Ear Muffs, helmets,
Glovesetc.
 Take care of your safety and Environment safety.
 Never go in Restricted Area.
 First take permission from your seniors to visit the industry.

SUGESTION AND RECOMMENDATION
1. INCREASE THE EFFICIENCY OF TRANSFORMERS
TO PREVENT YOUR SYSTEM FROM DISSOLVE GASSES THEY SHOULD INCREASE
VALUE OF TRANSFORMER.
2. REMOVING MOISTURE IN SUPER-HEATED STEAM
THEY SHOULD MAKE A SAFE DISTANCE BETWEEN PIPES USED FOR SUPER
HEATER AND EVAPORATOR IN STEAM DRUM.
3. SAFETY OF INTERNEE
PROVIDE PPS TO INTERNS FOR SAFETY.
PROVIDE SAFETY SHOES TO INTERNS FOR SAFETY.
PROVIDE SAFETY HELMET TO INTERNS FOR SAFETY.
PROVIDE EAR PROTECTOR TO INTERNS FOR SAFETY.
4. TRANSPORT FACILITY
PROVIDE TRANSPORT TO INTERNS.
5. SCHEDULE
PROVIDE INTERNSHIP SCHEDULE.
6. GOOD BEHAVIOR
DO NOT BURN BRIDGES AND BEHAVE GOOD WITH INTERNS.
CONSIDER INTERNS AS STUDENTS.
MAKE POSSIBLE LEARNING FOR INTERNS.

CONCLUSION
On the whole, this internship was a useful experience. I have
gained new knowledge and met many new people. I got insight into
professional practice. I learned the different facts of working within
a company.
The internship was also good to find out what are my strengths and
weaknesses. This helped me to define what skills and knowledge I
have to improve in the coming time. This internship was definitely
beneficial for me.

combine cycle diesel power plant

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (20)

Ähnlich wie combine cycle diesel power plant

Ähnlich wie combine cycle diesel power plant (20)

Mehr von Jawad Ali

Mehr von Jawad Ali (7)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

combine cycle diesel power plant