A

MINI PROJECT REPORT

ON
“WORKING OF THERMAL POWER PLANT AND
GENERATOR PROTECTIVE SYSTEM ”

Submitted in partial fulfillment for the award of the Degree of

BACHELOR OF TECHNOLOGY
IN
ELECTRICAL AND ELECTRONICS ENGINEERING
Submitted by

RADHANDI AJITH (22285A0203)

CHITTABOINA SAI PRANATH (22285A0226)
BURLA AKHILA (22285A0227)

Under the Guidance of

Mr. P. RAM REDDY
(Assistant professor)

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

KAMALA INSTITUTE OF TECHNOLOGY AND SCIENCE

(Approved by AICTE, Affiliated to J.N.T.U Hyderabad & Accredited by NAAC with A++, NBA )

Sponsored by Kamala Education Society.

SINGAPUR(V), HUZURABAD(M), KARIMNAGAR -505468 (T.G)

(2024-2025)
 KAMALA INSTITUTE OF TECHNOLOGY & SCIENCE

(Approved by AICTE, Affiliated to J.N.T.U Hyderabad & Accredited by NAAC with A++, NBA)
Sponsored by Kamala Education Society

SINGAPUR, HUZURABAD, KARIMNAGAR -505468 (T.G)

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

CERTIFICATE

This is to certify that RADHANDI AJITH (22285A0203), CHITTABOINA SAI

PRANATH (22285A0226), BURLA AKHILA (22285A0227), of IV year B. Tech has
satisfactorily completed the module of Mini-project entitled “WORKING THERMAL
POWER PLANT AND GENERATOR PROTECTIVE SYSTEM” under my
supervision and guidance towards partial fulfillment of requirements for the award
of degree of Bachelor of Technology in Electrical & Electronics Engineering to
JNTU-Hyderabad, T.G. during the year 2024-2025.

Project Guide Head of the Department

Mr. P. RAM REDDY Dr. YOGESH. Y. PUNDLIK
(Assistant Professor) (Professor)

Principal
Dr. K. ESWARAIAH
 ACKNOWLEDGEMENT

The satisfaction that accompanies the successful completion of any task would be
incomplete without the mention of people who made it possible and whose
encouragement and guidance has been the source of inspiration throughout the
course of work.

We express our deep sense of gratitude and sincere thanks to my project guide,
Mr. P. RAM REDDY, Assistant Professor of Electrical and Electronics
Engineering for his valuable guidance, inspiration, and constant encouragement
throughout the course of this work.
We wish to express our healthy gratitude to coordinator Mr. CH. BHASKAR,
Assistant Professor of EEE department for patience & for gratuitous co-operation
extended by him & who has given us valuable suggestions.

We owe our sincere thanks to Dr. YOGESH. Y. PUNDLIK, Head ofElectrical and
Electronics department and all other electrical engineering lecturers for the timely
suggestions and guidance.

We are also thankful to our principal Dr. K. ESWARAIAH who has always been
our backing force.
We place our sincere gratitude to Prof. K. SHANKER, Director OF KAMALA
INSTITUTE OF TECHNOLOGY AND SCIENCE for his support.

We would also like to express our heartfelt thanks to our in-charge officer and
support guide at Kesoram Cement, Basanthnagar.

Presented By:
RADHANDI AJITH (22285A0203)
CHITTABOINA SAIPRANATH (20281A0210)
BURLA AKHILA (22285A0227)
 ABSTRACT

This project Cement seldom used on its own, but rather to bind sand and gravel
together is operation of cement mill the clinker first cement from the clinker storage
piles to the clinker hopper through the deep bucket conveyer, then transferred to the
polycom, it crushes and machines like ECIT crane raw mill & different machines
drilling machines surveying lab etc. A substation receives electrical power
generating station via incoming transmission line & delivery electrical power
through feeders this is used for controlling the power on different router. Basically
substation consists of power transformed circuit breaker, relays, voltage,
transformers, isolators, earthing switches, synchronizing condensers/capacitor
tanks etc. Actually the incoming power is 132KV from malyalapally substation but
whole factory uses the 6.6 KV only per day, secondary option of the factory power
takes from the 15MW thermal powerplant it is near Basanthnagar kesoram
cement factory.
 CONTENTS
CHAPTER TITLE PAGE NO
1. INTRODUCTION 1-2
2. SUBSTATION 3-12
3. THERMAL POWER PLANT 13-16
4. SAFTEY 17
5. GENERATOR PROTECTIVE SYSTEM 18-23
5.1 Generator
5.2 Synchronous generator
5.3 Generator excitation
5.4 Excitation construction
6. CEMENT MILLS 24-28
6.1 Introduction of cement mills
6.2 Kiln
6.3 Raw mills
7. CRUSHER 29-32
7.1 Lime stone crusher
7.2 Primary crusher
7.3 Secondary crusher
7.4 Teritary crusher
7.5 Components of crusher
CONCLUSION 33
REFERENCE 34
 LIST OF FIGURES

Fig no Name Page

no
1.1 Plant line diagram 2

2.1 Line diagram of 132KV supply from malyalapally substation 3

2.2 5
Instrument transformer
2.3 5
Current transformer
2.4 6
Potential transformer
2.5 Insulators 6
2.6 Isolator 7
2.7 Busbars 7
2.8 Lighting arrestors 8

2.9 Circuit breakers 8

2.10 Relays 9

2.11 9
Capacitor banks
2.12 Batteries 10
2.13 Wave trapper 10

2.14 Switch yard 11

3.1 Layout and working of a thermal power plant 13
5.1 Brushless excitor 20
5.2 Brush exciter 21
5.3 Rotor 21
5.4 Schematic of DC-AC excitation without the measurement 22
equipment.

5.5 Schematic of the rectifier 23

6.1 Cement mill 24

6.2 Layout of cement mill 25
6.3 Kiln layout 26
7.1 Primary crusher 30
7.2 Secondary crusher 31
7.3 Tertiary crusher 31
 CHAPTER-1
INTRODUCTION

Introduction
Kesoram Industries Limited is one of the pioneer companies in India. It is under the
flagship BK Birla Group of Companies. Its production ranges from tires to cement
to rayon. Kesoram Industries installed a small stationary packing unit Kesoram
Industries entered into a joint venture with Maharashtra Seamless Limited and
Dhariwal Infrastructure Private Limited in 2012 for working a coal block allocated
to it by the Central Government in the State of Maharashtra Kesoram Industries
Limited (KIL) has diversified business including tyres, cement and rayon. The
company owns and operates two integrated tyre manufacturing plants located at
Balasore, Odisha (the "BalasoreTyre Plant") and Haridwar, Uttarakhand (The
"LaksarTyre Plant"). The tyres are marketed under the brand name "Birla Tyres".
KIL also owns and operates two cement manufacturing plants, located at Sedam,
Karnataka (the "Vasavadatta Cement Plant") and Basanthnagar, Andhra Pradesh
(the "Kesoram Cement Plant"). The company manufactures viscose rayon, filament
yarn and transparent paper. The rayon is marketed under the brand name "Kesoram
Rayon", while transparent paper is marketed under the brand name "Kesophane"
The company, incorporated in 1919, was originally known as Kesoram Cotton Mills
Limited and is based in Kolkata.
Power input
 The Power is Taken In 2 ways
1. Near By Substation
2. Own power Generation
The power is taken form the malyalapalli substation 132kv the Power Flow diagram
is in the following slide The Plant own power Generation is in the next slide too.
It's the single line diagram of whole plant.

1
Plant single Line diagram

Fig :1.1 plant line diagram

2
 CHAPTER-2
SUBSTATION
A substation is a part of an electrical generation, transmission, and distribution
system Substations transform voltage from high to low, or the reverse, or perform
any of several other important functions. Between the generating station and
consumer, electric power may flow through several substations at different voltage
levels A substation may include transformers to change voltage levels between high
transmission voltages and lower distribution voltages, or at the interconnection of
two different transmission voltages.
132KV supply from malyalapally substation

Fig:2.1 132KV supply from malyalapalli substation

The power is taken form the malyalapalli substation 132KV then the factory uses
only 6.6KV secondary option of the factory to take the power supplyfrom the
Basanthnagar 15MW powerplant.

3
Components of substation
1. Instrument Transformers
2. Current Transformer
3. Potential Transformer
4. Conductors
5. Insulators
6. Isolators
7. Busbars
8. Lightning Arrestors
9. Circuit Breakers
10. Relays
11. Capacitor Banks
12. Batteries
13. Wave Trapper
14. Switch Yard
15. Metering and Indication Instruments
16. Equipment for Carrier Current
17. Prevention from Surge Voltage
18. The Outgoing Feeders

1. Instrument Transformers:
The instrument transformer is a static device utilized for reduction of higher
currents and voltages for safe and practical usage which are measurable with
traditional instruments such as digital multi-meter etc. The value range is from 1A
to SA and voltages such as 110V etc. The transformers are also used for actuation
of AC protective relay through supporting voltage and current Instrument

4
transformers are shown in the figure below and its two types are also discussed
undeneeth.

Fig:2.2 Instrument transformer

2.Current Transformer
A current transformer is a gadget utilized for the transformation of higher value
currents into lower values. It is utilized in an analogous manner to that of AC
instruments, control apparatus, and meters. These are having lower current ratings
and are used for maintenance and installation of current relays for protection
purpose in substations

Fig.2.3 Current transformer

5
3. Potential Transformer:
The potential transformers are similar in characteristics as current transformers but
are utilized for converting high voltages to lower voltages for protection of relay
system and for lower rating metering of voltage measurements.

Fig.2.4 Potential Transformer

4. Conductors:
Conductors are the materials which permit flow of electrons through it. The best
conductors are copper and aluminum etc. The conductors are utilized for
transmission of energy from place to place over substations.
5.Insulators:
The insulators are the materials which do not permit flow of electrons through it.
Insulators are resisting electric property. There are numerous types of insulators
such as shackle, strain type, suspension type, and stray type ete Insulators are used
in substations for avoiding contact with humans or short circuit.

Fig.2.5 Insulator

6
6.Isolators:
The isolators in substations are mechanical switches which are deployed for
isolation of circuits when there is an interruption of current. These are also known
with the name of disconnected switches operation under no-load conditions and are
not fortified with are- quenching devices. These switches have no specific current
breaking value neither these have current making value. These are mechanically
operated switches

Fig.2.6 Isolators

7.Busbars:
The busbar is among the most important elements of the substation and is a
conductor which carries current to a point having numerous connections with it.
The busbar is a kind of electrical junction which has outgoing and incoming current
paths. Whenever a fault occurs in the busbar, entire components connected to that
specific section should be tripped for giving thorough isolation in a small time, for
instance, 60ms for avoiding danger rising due to conductor's heat. These are of
different types such as ring bus, double bus, and single bus etc. A simple bus bar is
shown in the figure below which is considered as one of the most vital electrical
substation components.

Fig.2.7 Busbar in substation

7
8. The Lightning Arresters:
The lightning arresters can be considered as the first ever components of a
substation. These are having a function of protecting equipment of substation from
high voltages and are also limiting the amplitude and duration of the current's flow.
These are connected amid earth and line ie. connected in line with equipment in the
substation. These are meant for diversion of current to earth if any current surge
appears hence by protecting insulation as well as conductor from damages. These
are of various types and are distinguished based on duties.

Fig.2.8 Lighting Arrester

9. Circuit Breakers:
The circuit breakers are such type of switches utilized for closing or opening circuits
at the time when a fault occurs within the system. The circuit breaker has 2 mobile
contacts which are in OFF condition in normal situations. At the time when any
fault occurs in the system, a relay is sending the tripped command to the circuit
breaker which moves the contacts apart, hence avoiding any damage to the circuitry.

Fig.2.9 Circuit Breaker in Substation

8
10.Relays:
Relays are a dedicated component of electrical substation equipment for the
protection of system against abnormal situations e g faults. Relays are basically
sensing gadgets which are devoted for sensing faults and are determining its
location as well as sending interruption message of tripped command to the specific
point of the circuit. A circuit breaker is falling apart its contacts after getting the
command from relays. These are protecting equipment from other damages as well
such as fire, the risk to human life, and removal of fault from a particular section of
the substation. Following is the substation component diagram is known as a relay.

Fig.2.10 Relays

11.Capacitor Banks:
The capacitor bank is defined as a set of numerous identical capacitors which are
connected either in parallel or series inside an enclosure and are utilized for the
correction of power factor as well as protection of circuitry of the substation. These
are acting like the source of reactive power and are thus reducing phase difference
amid current and voltage. These are increasing the capacity of ripple current of
supply and avoid unwanted selves in the substation system. The use of capacitor
banks is an economical technique for power factor maintenance and for correction
of problems related to power lag.

Fig.2.11 Capacitor bank in substation

9
12.Batteries:
Some of the important substation parts such as emergency lighting, relay system,
and automated control circuitry are operated through batteries. The size of the
battery bank is depending on the voltage required for operation of the DC circuit
respectively The storage batteries are of two basic types i.e. acid-alkaline batteries
and lead-acid batteries. The lead acid batteries are of the most common type and
used in substations in abundance as these provide high voltages and are cheaper in
cost.

Fig.2.12 Substation Batteries

13.Wave Trapper:
The wave trapper is one of the substation components which is placed on the
incoming lines for trapping of high-frequency waves. The high-frequency waves
which are coming from nearby substations or other localities are disturbing the
current and voltages, hence its trapping is of great importance. The wave trapper is
basically tripping high-frequency waves and is then diverting the waves into
telecom panel.

Fig.2.13 Wave Trapper in Substation

10
14.Switchyard:
The switchyards, switches, circuit breakers, and transformers for the connection and
disconnection of transformers and circuit breakers. These are also having lighting
arrestors to protect the substation or power station from strokes of natural lighting.

Fig.2.14 Switch Yard

15.Metering and Indication Instruments:

There are mumerous instruments for metering and indication in each substation
such as watt- meters, voltmeters, ammeters, power factor meters, kWh meters, volt-
ampere meters, and KVARH meters etc. These instruments are installed at different
places within substation for controlling and maintaining values of current and
voltages For instance, 33/11KV substation equipment will comprise digital multi-
meters for various readings of currents and voltages.

16. Equipment for Carrier Current:

The equipment of carrier current is installed in the substation for the purpose of
communication, supervisory control, telemetry, and/or relaying etc. Such
equipment is often mounted on a room which is known as carrier room and is
connected across the power circuit highvoltages

17.Prevention from Surge Voltage:

The transient of overvoltages substation system is because of inherent and natural
characteristics. There are several reasons for overvoltages which may be caused due
to a sudden alteration in conditions of the system eg. load rejection, faults, or
switching operations etc or because of lighting ete. The types of overvoltages can
be classified into two Le switching generated or lightning generated. However, the
scale of overvoltages could be over maximum allowable voltage levels, hence these
are required to be protected and reduced for avoiding damage to instruments,
equipment, and lines of a substation.

11
18. The Outgoing Feeders:
There are numerous outgoing feeders which are connected to that of substations.
Basically, the connection is with a bus of the substation for carrying power from the
substation to service points. The feeders can hug overhead streets, underground,
underneath streets, and are carrying electrical power to that of distribution
transformers at near or farther premises. The isolator in substation and breaker of
the feeder are considered as entities of the substation and are of metal-clad typically.
Whenever a fault is occurring in the feeder, the protection is detecting and the circuit
breaker is opened. After detection of fault through manual or automatic way, there
are more than one attempts for re-energraing the feeder.

12
 CHAPTER-3
THERMAL POWER PLANT
A thermal power plant is a power plant where steam is used to drive a steam turbine.
This turbine is connected to an electrical generator. After this, the water is
condensed, and may be used again. This is known as the Rankine cycle. There are
different procedures that can be used to heat the water
Typical layout and working of a Thermal Power Plant

Fig.3.1 Layout and working of a thermal power plant

3.1 Working priciple:

A thermal power station is a power station in which heat energy is converted to
electric power. In most places the turbine is steam-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 and recycled to
where it was heated. This is known as a Rankine cycle. The greatest variation in the

13
design of thermal power stations is due to the different heat sources, fossil fuel
power generation, though nuclear heat energy, solar heat energy, biofuels, andwaste
incineration are also used. Some prefer to use the term energy center because such
facilities convert forms of heat energy into electrical energy certain thermal power
stations are also designed to produce heat for industrial purposes, for district
heating, or desalination of water, in addition to generating electrical power.
4.2 Components of thermal power plant
1. Coal
2. Boiler

 Super heater
 Economizer
 Air pre heater
3. Steam turbine
4. Condenser
5. Alternater
6. Feed water pump
7. Chimney
8. Pulverizer
9. Precipitator
10. Cooling tower
1.Coal: in a coul based thermal power plant, coal is transported from coal mines to
the generating station. Generally, bituminous coal or brown coal is used as fuel The
coal is stored in either 'dead storage or in 'live storage. Dead storage is generally 40
days backup coal storage which is used when coal supply is unavailable. Live
storage is a raw coal bunker in boiler house. The coal is cleaned in a magnetic
cleaner to filter out if any iron particles are present which may cause wear and tear
in the equipment. The coal from live storage is first crushed in small particles and
then taken into pulverizer to make it in powdered form. Fine powdered coal
undergoes complete combustion, and thus pulverized coal improves efficiency of
the boiler. The ash produced after the combustion of coal is taken out of the boiler
furnace and then properly disposed. Periodic removal of ash from the boiler furnace
is necessary for the proper combustion
2.Boiler: The mixture of pulverized coal and air (usually preheated air) is taken into
boiler and then burnt in the combustion zone. On ignition of fuel a large fireball is
formed at the center of the boiler and large amount of heat energy is radiated from
it. The heat energy is utilized to convert the water into steam at high temperature
and pressure. Steel tubes run along the boiler walls in which water is converted in
steam. The flue gases from the boiler make their way through superheater,

14
economizer, air preheater and finally get exhausted to the atmosphere
from the chimney.
 Superheater: The superheater tubes are hanged at the hottest part of the
boiler. The saturated steam produced in the boiler tubes is superheated to
about 540 °C in the superheater The superheated high pressure steam is then
fed to the steam turbine
 Economizer: An economizer is essentially a feed water heater which heats
the water before supplying to the boiler
 Air pre-heater: The primary air fan takes air from the atmosphere and it is
then warmed in the air pre-heater. Pre-heated air is injected with coal in the
boiler. The advantage of pre-heating the air is that it improves the coal
combustion.
4.Steam turbine: High pressure super heated steam is fed to the steam turbine
which causes turbing blades to rotate. Energy in the steam is converted into
mechanical energy in the steam turbine which acts as the prime mover. The pressure
and temperature of the steam falls to a lower value and it expands in volume as it
passes through the turbine The expanded low pressure steam is exhausted in the
condenser
5. Condenser: The exhausted steam is condensed in the condenser by means of
cold water circulation. Here, the steam loses it's pressure as well as temperature and
it is converted back into water. Condensing is essential because, compressing a fluid
which is in gaseous state requires a huge amount of energy with respect to the
energy required in compressing liquid. Thus, condensing increases efficiency of the
cycle
6. Alternater: the steam turbine is coupled to an alternator. When the turbine rotates
the alternator, electrical energy is generated. This generated electrical voltage is
then stepped up with the help of a transformer and then transmitted where it is to be
utilized
7. Feed water pump: The condensed water is again fed to the boiler by a feed water
pump Some water may be lost during the cycle, which is suitably supplied from an
external water source
8. Chimney: The Chimney is a structure which provides ventilation for hot flue
gases or smoke coming out of boiler and furnace. The size of chimney depends on
the size of boiler and environmental regulation of factory/power plant location. 9.
9. Pulverizer: A pulverizer or grinder is a mechanical device for the grinding of
many different types of materials. For example, a pulverizerpuritch is used to
pulverize coal for combustion in the steam-generating furnaces of coal power
plants.
10. Cooling Tower: A cooling tower is a heat rejection device that rejects waste
heat to the atmosphere through the cooling of a water stream to a lower temperature
Cooling towers may either use the evaporation of water to remove process heat and

15
cool the working fluid to near the wet-bulb air temperature or, in the case of closed
circuit dry cooling towers, rely solely on air to cool the working fluid to near the
dry-bulb air temperature.

16
 CHAPTER-4
SAFETY
2.1 FactoryAct:
The factories Act, 1948, as amended by the factories act, 1987, serves to assist in
formulation national policies in india with respect to occupation safety and health
in factories and docks in india. It deals with various problem concerning safety,
health, efficiency and well-being of the persons at work places.
2.2 Safety equipments:

o Safety Harness
o Respiratory Mask
o Safety Glasses
o Hearing Protection (Headphones)
o Protective Clothing
o Face Shield
o Safety Helmets
o Reflective Clothing
o Foot Protection

2.3 Safety:
 Be sure you know how to perform the job and perform it safely
 Always work clean of suspended loads.
 Never conduct work, unless trained.
 Wear the required personal protective equipment necessary for the job.
 Safety glasses are required as minimum eye protection on all job sites.
 Obey all warning signs and barricades.

17
 CHAPTER-5
GENERATOR PROTECTIVE SYSTEM
5.1 Generator:
A generator is a machine by which mechanical energy is transformed into electrical
energy.
Generator ratings:
Out put power : 19625 KVA
No of phases :3
No of poles :4
Arm. Voltage : 6600V
Arm. Current : 1717A
Frequency : 50HZ
Speed : 1500RPM
P.f : 0.8
Field voltage : 195V
Field current : 450A
Coolant temp : 450
Weight : 45tones
Date : 1996

5.2 SYNCHRONOUS GENERATOR

Synchronous machines:
The synchronous machine is an important electromechanical energy converter.
Synchronous generators usually operate together, forming a large power system
supplying electrical energy to the loads or consumers. For high-speed machines, the
prime movers are usually steam turbines employing fossil or nuclear energy
resources.

18
Types of synchronous machines:
According to the arrangement of the field and armature windings, synchronous
machines may be classified as rotating armature type or rotating field type.
Rotating-Armature Generator
 The rotating-armature generator rotates in a stationary magnetic field. The
armature is what produces the power in a generator. To help with this, slip
rings are used. A slip ring is a type of connector. Two are needed one goes
on each side of the field to connect the power. This type of alternator is not
used very often because it does not provide power in the large quantities
often needed by a generator.
Rotating-Field Alternator
 With the rotating-field alternator, the alternator itself is stationary while the
field rotates. Because the armature is not moving, the power can be
connected right to the source that needs the power. For this reason the
rotating-field alternator is the more commonly used of the two types of
rotating AC generators
Synchronous generator supplying an isolated load
 When a synchronous generator is excited with field current and is driven at
a constant speed, a balanced voltage is generated in the armature winding.
If a balanced load is now connected to the armature winding, a halanced
armature current at the same frequency as the emf will flow. since the
frequency of generated emf is related to the rotor speed, while the speed of
the armature rotating mmf is related to the frequency of the current, it
follows that the armature mmf rotates synchronously with the rotor field.
Synchronising procedure
The process of paralleling a synchronous machine onto infinite bus bars is known
as synchronising. Before a synchronous generator can be synchronized onto live
bus bars, the following conditions must be satisfied.

 The frequency of the generator must be equal to that of the bus bars.
 The phase sequence of the generator must be the same as that of the bus bars
 At the instant of synchronising, the voltage phasors of the generator and the
bus bars must coincide.
Exciter device:
An Electric source that comes from three phase ac exciter is rectified to de by the
rotary rectifier with silicon rectifier, then, that de electric source excites the field
coil of generator.

19
Rotory rectifier:
The rotary rectifier consists of silicon rectifier, protecting condenser and attachment
rings. The attachment rings keep the silicon rectifier and condenser against the
centrifugal force. Silicon rectifier stands against high centrifugal force.
Gear box:
Gear box provides speed and torque conversions from a rotating power source to
another device are in gear ratio-transmission reduces higher engine speed to the
slower wheel speed increases torque in the process. Transmission will have multiple
gear ratios with the ability to switch between them as speed varies. Directional
control can also be provided.
Brushless excitor:
A brushless alternator is composed of two alternators built end-to-end on one shaft.
Smaller brushless alternators may look like one unit but the two parts are readily
identifiable on the large versions. The larger of the two sections is the main
alternator and the smaller one is the exciter. The exciter has stationary field coils
and a rotating armature (power coils). The main alternator uses the opposite
configuration with a rotating field and stationary armature. A bridge rectifier, called
the rotating rectifier assembly, is mounted on a plate attached to the rotor. Neither
brushes nor slip rings are used, which reduces the number of wearing parts. The
main alternator has a rotating field as described above and a stationary armature
(power generation windings).
Varying the amount of current through the stationary exciter field coils varies the 3-
phase output from the exciter. This output is rectified by a rotating rectifier
assembly, mounted on the rotor, and the resultant DC supplies the rotating field of
the main alternator and hence alternator output. The result of all this is that a small
DC exciter current indirectly controls the output of the main alternator.

Fig.5.1 brushless excitor

20
Brush exciter:

Fig.5.2 Brush exciter

Rotor:
Two types of rotors used in alternators are

 Salient pole rotor type and

 Cylindrical rotor type

Fig.5.3 Rotor

 Salient pole type rotor is used in low and medium speed alternator.
 Cylindrical rotor is used for steam turbine driven alternators.

Damper windings:
The damper winding is a path for the circulation of induced currents when the
generator is operating at other than the rated speed. Damper windings are used in
the synchronous motors to help them produce the required starting torque rather

21
than another motor to use to start them. Damper windings act as an induction motor
in a synchronous motors. it is highly economical.
5.2 GENERATOR EXCITATION
Direct-current excitation
Direct current supplied excitation (DC-AC excitation) is the most commonly used
brushless excitation method in which the excitation power to the rotor is supplied
by a separate excitation machine. The excitation machine is usually installed in the
main frame and on the same shaft as the main machine.
The DC-AC excitation machine is a salient-pole external-pole generator that has its
field winding in the stator and armature winding in the rotor. As the rotor rotates,
the direct current supplied to the stator winding induces a three-phase alternating
current into the rotor winding. This current is rectified into direct excitation current
using a diode bridge installed in the rotor. The frequency of the rotor current before
the rectifier is fronpm, where n is the mechanical rotation frequency of the rotor
and p is the number of pole pairs in the excitation machine. The pole-pair number
of the excitation machine is typically 13 or 17 which is larger than that of the main
machine.
For the control of the voltage or reactive power of the main machine, the stator
current is controlled by an automatic voltage regulator (AVR). The excitation power
can be obtained using voltage and current transformers, an auxiliary winding
installed in the stator slots of the main machine or a separate permanent magnet
generator (PMG). In the first two cases, one of the stator poles must be a permanent
magnet to enable self-excitation. In each case, instrument transformers for voltages
and currents are needed for the regulator to control the voltage and power. The
regulator and supply of the excitation power are considered later in this work.

Fig.5.4 schematic of DC-AC excitation without the measurement equipment.

5.3 EXCITATION CONSTRUCTION

1. Excitation machine: In low-voltage synchronous generators, brushless DC-AC
excitation is used. The excitation machine is mounted inside the generator frame on

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to the non-drive end. The exciter stator has salient poles one of which is a
permanent-magnet pole to obtain self- excitation in case the excitation power is not
provided by a separate permanent-magnet generator. The permanent-magnet pole is
magnetized during the manufacturing by using a winding wound around the pole
the exciter rotor is slotted and has a three-phase single-layer diamond winding with
one slot per pole and per phase and each pole pair connected in parallel.

Fig.5.5 schematic of the rectifier

2. Rotating rectifier
The three-phase voltage induced into the exciter rotor winding is rectified and
supplied to the main field winding. The rectifier is a six-pulse diode bridge mounted
on the exciter rotor. A varistor protects the system from overvoltage peaks and a RC
snubber damps the voltage peaks caused by the diodes.

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 CHAPTER-6
CEMENT MILLS

6.1 Introduction

 A Cement mill is the equipment used to grind the hard, nodular clinker from
the cement kiln into the fine grey powder that is cement.
 Most cement is currently ground in ball mills and also vertical roller mills
which are more effective than ball mills

Fig.6.1 Cement mill

Working Principle:

 In case of continuously operated ball mill, the material to be ground is fed

from the left through a 60° cone and the product is discharged through a 30°
cone to the right.
 As the shell rotates, the balls are lifted upon the rising side of the shell and
ten they cascade down from near the top of the shell.

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  In doing so, the solid particles in between the balls and ground are reduced
in size by impact.
 The ball mill is a key piece of equipment for grinding crushed materials, and
it is widely used in production lines for powders such as cement, silicates,
refractory material, fertilizer, glass ceramics, etc, as well as for ore dressing
of both ferrous and non-ferrous metal.

Fig.6.2 Cement mill layout

6.2 kiln

Introduction

A kiln is a thermally insulated chamber, a type of oven, which produces

temperatures sufficient to complete some process, such as hardening, drying, or
chemical changes. Kilns have be ensued for millennia to turn objects made from
clay into pottery, tiles and bricks various industries use rotary kilns for
pyroprocessing to calcinate ores, to calcinate limestone to lime for cement, and to
transform many other materials.

Rotary kiln

A rotary kiln is a pyroprocessing device used to raise materials to a high temperature

(calcination) in a continuous process.

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Materials produced using rotary kilns include:

o Cement
o Lime, Refractories, Metakaolin
o Titanium dioxide
o Alumina
o Vermiculite
o Iron ore pellets

Working Principle:

 The kiln is a cylindrical vessel, inclined lightly to the horizontal, which is

rotated slowly about its longitudinal axis.
 The process feed stock is fed into the upper end of the cylinder. As the kiln
rotates, material gradually moves down toward the lower end, and may
undergo a certain amount of stirring and mixing.
 Hot gases pass along the kiln, sometimes in the same direction as the
process material but usually in the opposite direction.

The hot gases may be generated in an external furnace, or may be generated By a

flame inside the kiln

Fig.6.3 Kiln layout diagram

Construction of Kiln:

 Kiln shell
 Refractory lining
 Tires and rollers
 Drive gear

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6.3 Raw Mill

A raw mill is the equipment used to grind raw materials into "raw mix" during the
manufacture of cement.Which is then fed to a cement kiln, which transforms it into
clinker, which is then ground to make cement in the cement mill.

Types of raw mill:

a. Wet raw mills

b. Wash mill

c. Ball mills & wash drums

d. Dry raw mills

e. Ball mills& Roller mill

a). Wet raw mills:

o Wet grinding is more efficient than dry grinding because water coats the
newly formed surfaces of broken particles and prevents re-agglomeration.
o The disadvantage is that the water in the resultant slurry has to be removed
subsequently, and this usually requires a lot of energy

b). Wash mill

o This represents the earliest rawmilling technology, and was used to grind
soft materials such as chalk and clay

c). Ball mills and wash drums:

o The ball mill allows grinding of the harder lime stones that are more
common than chalk
o The various mineral components of the rawmix are fed to the mill at a
constant rate along with water, and the slurry runs from the outlet end

d). Dry raw mills:

o Dry raw mills are the normal technology installed today, allowing
minimization of energy consumption and CO2 emissions.

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 o A hot-aur furnace may be used to supply this heat, but usually hot waste
gases from the kiln are used.

e). Ball mills:

o These are similar to cement mills, but often with a larger gas flow.
o The gas temperature is controlled by cold-air bleeds to ensure a dry product
without overheating the mill.

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 CHAPTER-7

CRUSHER

Introduction

A crusher is a machine designed to reduce large rocks into smaller rocks, gravel, or
rock dust. Crushers may be used to reduce the size, or change the form, of waste
materials. Crushing is the process of transferring a force amplified by mechanical
advantage through a material made of molecules that bond together more strongly,
and resist deformation more, than those in the material being crushed do

7.1 Lime stone crusher:

 A type of crusher used to cut the lime stone into small pieces.
 RCL's L&T Hazemag, a German-made impact crusher, is then used to crush
1,200mm limestone boulders into 70mm limestone pieces.
 In this stage of the production process, the apron feeder uniformly pushes
the limestone boulders into the crusher. Thehydraulic, adjustable impact
aprons are provided to break the limestone boulders into smaller pieces.

7.2 Primary crusher:

 A primary crusher is one of the main types of primary crushers in a mine or

ore processing plant
 Gyratory crushers can be used for primary or secondary crushing.
 Lime stone crusher, size-200mm to 150min.
 For this crusher there is not hammers.

29
 Fig.7.1 primary crusher

7.3 Secondary crusher:

 line after the primary crushing to further reduce the particle size of shale or
other Jock
 Secondary Crushing Equipment. The term "secondary crushing" single or
multiple, which follows immediately after the primary crusher, taking all or
a portion of the product of the primary crushing stage as its feed
 The crushing size of secondary crusher is 40mm to 2mm.

Fig.7.2 Secondary crusher

7.4 Tertiary crusher:

 The third stage in crushing, following primary and secondary crushing

 Tertiary impact crushers are an excellent solution in the production of
fine particles

30
  Tertiary Impact Crushers are used to produce 5-0 mm sand type material as
Tertiary and Secondary crushers.
 SAES Tertiary Impact Crushers, with have low initial investment costs, have
a low filler mtió and wear and a high obtaining ratio for sand owing to
thespecial design of impactplates and high speed rotor.

Fig.7.3 Tertiary crusher

Components of crusher:

 Crushing plants make use of a large range of equipment, such as a pre-

screener, loading conveyor, intake hopper, magnetic separator, crushing
unit, such as jaw crushers, and cone crusher etc.
 Vibratory Feeder
 Crusher
 Vibrating Screen
 Belt Conveyor
 Central electric Control system

Vibratory Feeder:

 A vibratory feeder is an instrument that uses vibration to "feed" material to

a process or machine
 Vibratory feeders use both vibration and gravity to move material.
 Gravity is used to determine the direction, either down, or down and is used
to move the material and then vibration.

Types of Vibratory Feeders:

31
1. Vibratory Tray Feeders

2. Vibratory Tubular feeders

3. Heavy Duty Feeders.

Conveyor Belts:

A conveyor system is a common piece of mechanical handling equipment that

moves materials from one place to another. Conveyors ara especially useful in
applications involving the transportation of heavy or bulky materiais

Minerials Sizes:

 The basic concept of the mineral size is the use of two rotors with large
teeth, on small diameter shafts, driven at a low speed by a direct high
torque drive system.
 This design produces three major principles which all interact when
breaking materials using sizer technology.

32
 CHAPTER-8
CONCLUSION
The conclusion of our industrial oriented mini project in kesoram cement factory,
we studied about the process of cement factory and power supply of substation
belongs to the malyalapally village. The substation send the 132KV of power to the
factory and the whole factory uses the 6.6KV only the remaining on hold. Power
used by the crushers, mills, office etc. And it is uses only 6.6 KV per day. The
factory has another option to take power from the 15 MW thermal power plant

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 CHAPTER-9
REFERENCES

1. https://en.wikipedia.org/wiki/Kesoram_Industries_Ltd.
2. https://www.birlashakticement.com/

3. https://www.tvh.com/en-in/blog/7-types-
of-personal-protective- equipment-ppe-
toguarantee-your-safety

4. https://www.kemperequipment.com/blo
g/answered-common- questions-about-
jawcrushers/
5. https://en.wikipedia.org/wiki/Rawmill#History

6. http://www.cementmillequipment.com/cement-
grinding/cementballmiller.html#:~:text=of%20the%
20feed.,The%20inside%2 0of%20the
%20cylinder%20i
s%20filled%20with%20grinding%20media,the%20
inner%20wall%20of%20the
7. https://en.wikipedia.org/wiki/Cement_kiln#:~:text=Cement%20kilns%2
0are
%20used%2 0for,a%20mixture%20of%20calcium%20silicates.
8. https://en.wikipedia.org/wiki/Cement_mill

34