1

LOCOMOTIVE WORKSHOP

NORTHEN RAILWAY, CHARBAGH

LUCKNOW

A

INDUSTRIAL TRAINING REPORT

ON

TYPES OF GENERATORS AND ITS

CHARACTERISTICS

SUBMIETTED TO : SUBIMITTED TO:

PRINCIPAL : SK . SHARMA MUKESH MAURYA

STC /CB , ELECTRICAL ENGG. (III year)

LUCKNOW ROLL N. 1505420901

REGD. N.: B-893

2

ACKNOWLEDGEMENT

I take this opportunity my sincere thanks and deep gratitude to Dr. MONIKA

MEHROTRA (HEAD OF ELECTRICAL DEPARTMENT) all these people who

extended their whole hearted co-operation and helped me in completing this project

successfully.

First of all I would like to thanks all the S.S.E. and J.E. of the all the sections for

creating oppurtunities to undertake me in this esteemed organization. Special thanks to all

the department for all the help and guidance extended to me by them in every stage during

my training. His inspiring suggestions and timely guidance enabled me to perceive the

various aspects of the project in the new light.

In all I found a congenial work environment in DIESEL LOCOMOTIVE

WORKSHOP, CHARBAGH LUCKNOW and this completion of the project will mark a

new beginning for me in the coming days.

SUBMIETTED TO : SUBIMITTED TO:

PRINCIPAL : SK . SHARMA MUKESH MAURYA

STC /CB , ELECTRICAL ENGG. (III

year)

LUCKNOW ROLL N. 1505420901

REGD. N.: B-893

Date: 20 july 2017

3

Content

Page n.

1. Introduction ………………………………………………………………………3

1.1 Introduction to locomotives…………………………………………………....3

1.2 Diesel electric…………………………………………………………………..4

1.3 History……………………………………………………...…………………..6

2. Block diagram……………………………………………………………………….9

2.1 Block diagram of locomotive ………………….……………………………….9

2.2 Basic structure of LOCOMOTIVE ……………………………………………10

3. Power Distribution system in locomotives………………………………………..12

3.1 Main generator (traction alternator)…………………………………………….12

3.2 Companion alternator…………………………………………,…………………12

3.3 Auxiliary generator…………………………………………….…………………13

3.4 DC link voltage…………………………………………………………………..14

3.5 Dynamic braking………………………………………………………………….14

3.6 EM2000 computer………………………………………………………………..15

4. ELECTRICAL CONTROL CABINETS…………………….………………….16

5. MAJOR ELECTRICAL EQUIPMENTS OF LOCOMOTIVES……………..20

5.1 Main Alternator……………………………………………………….…………20

5.2Companion Alternator ……………………………………………………..……22

5.3Inertial Blower (Dustbin Blower)………………………………..……….……..23

5.4 RADIATOR COOLING FAN MOTORS…………………..…………….…….23

5.5 BATTERY……………………………………………….………………………24

5.6 AC Traction Motors……………………………………………..………………25

5.6.2 Traction motor run test…………………………………………………………27

5.7 Traction Motor Blower………………………………………….……………….27

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Page n.

5.8 TCC1 and TCC2 Inverters……………………………………………………………27

5.9 TCC Blower………………………………………………………………………….28

5.10 Radiator Cooling Fan Motors………………………………………………………..28

5.11 Computer EM 2000………………………………………………………………….29

5.12 Computer Control Brake………………………………………………………..…..29

5.13 Dynamic Brake Traction Control Computers………………………………......…..29

5.14 Under Truck………………………………………………………….……….…......30

6. Conclusion………………………………………………………………,…………….31

7. Refrences………………………………………………………………….………...…32

5

CHAPTER-1

Introduction

1.1 Introduction to Indian railways

Indian Railways is the state-owned railway company of India. It comes under

the Ministry of Railways. Indian Railways has one of the largest and busiest rail networks in

the world, transporting over 18 million passengers and more than 2 million tonnes of freight

daily. Its revenue is Rs.107.66 billion. It is the world's largest commercial employer, with

more than 1.4 million employees. It operates rail transport on 6,909 stations over a total route

length of more than 63,327 kilometers(39,350 miles).The fleet of Indian railway includes

over 200,000 (freight) wagons, 50,000 coaches and 8,000 locomotives. It also owns

locomotive and coach production facilities. It was founded in 1853 under the East India

Company.

Indian Railways is administered by the Railway Board. Indian Railways is

divided into 16 zones. Each zone railway is made up of a certain number of divisions. There

are a total of sixty-seven divisions.It also operates the Kolkata metro. There are six

manufacturing plants of the Indian Railways. The total length of track used by Indian

Railways is about 108,805 km (67,608 mi) while the total route length of the network is

63,465 km (39,435 mi). About 40% of the total track kilometer is electrified & almost all

electrified sections use 25,000 V AC. Indian railways uses four rail track gauges

Indian Railways operates about 9,000 passenger trains and transports 18

million passengers daily .Indian Railways makes 70% of its revenues and most of its profits

from the freight sector, and uses these profits to cross-subsidies the loss-making passenger

sector. The Rajdhani Express and Shatabdi Express are the fastest trains of India.

1.2 Diesel locomotive shed charbagh , Lucknow

Diesel locomotive shed is an industrial-technical setup, where repair and maintenance

works of diesel locomotives is carried out, so as to keep the loco working properly. It

contributes to increase the operational life of diesel locomotives and tries to minimize the line

failures. The technical manpower of a shed also increases the efficiency of the loco and

remedies the failures of loco.

6

The shed consists of the infrastructure to berth, dismantle, repair and test the loco and

subsystems. The shed working is heavily based on the manual methods of doing the

maintenance job and very less automation processes are used in sheds, especially in India.

The diesel shed usually has:-

Berths and platforms for loco maintenance.

Pits for under frame maintenance

Heavy lift cranes and lifting jacks

Fuel storage and lube oil storage, water treatment plant and testing labs etc.

Sub-assembly overhauling and repairing sections

Machine shop and welding facilities.

DIESEL SHED, CHARBAGH ,LUCKNOW of NORTHERN RAILWAY is located in

LUCKNOW The shed was established on 22nd April 1857. It was initially planned to home

75 locomotives. The shed cater the needs of Northern railway. This shed mainly provides

locomotive to run the mail, goods and passenger services. No doubt the reliability, safety

through preventive and predictive maintenance is high priority of the shed. To meet out the

quality standard shed has taken various steps and obtaining of the ISO-9001-200O& ISO

14001 OHSAS CERTIFICATION is among of them. The Diesel Shed is equipped with

modern machines and plant required for Maintenance of Diesel Locomotives and has an

attached store depot. To provide pollution free atmosphere, Diesel Shed has constructed

Effluent Treatment Plant. The morale of supervisors and staff of the shed is very high and

whole shed works like a well-knit team.

1.3 Introduction to locomotive

A diesel locomotive is a type of railway locomotive in which the prime mover is a diesel

engine. Several types of diesel locomotive have been developed, differing mainly in the

means by which mechanical power is conveyed to the driving wheels (drivers).

7

1.3 Diesel-Electric

A diesel–electric locomotive's power output is independent of road speed, as long as

the unit's generator current and voltage limits are not exceeded. Therefore, the unit's ability to

develop tractive effort (also referred to as drawbar pull or tractive force, which is what

actually propels the train) will tend to inversely vary with speed within these limits. (See

power curve below). Maintaining acceptable operating parameters was one of the principal

design considerations that had to be solved in early diesel–electric locomotive development

and, ultimately, led to the complex control systems in place on modern units.

Originally, the traction motors and generator were DC machines. Following the

development of high-capacity silicon rectifiers in the 1960s, the DC generator was replaced

by an alternator using a diode bridge to convert its output to DC. This advance greatly

improved locomotive reliability and decreased generator maintenance costs by elimination of

the commutator and brushes in the generator. Elimination of the brushes and commutator, in

turn, disposed of the possibility of a particularly destructive type of event referred to as

a flashover, which could result in immediate generator failure and, in some cases, start an

engine room fire.

The important components of diesel–electric propulsion are the diesel engine (also

known as the prime mover), the main generator/alternator-rectifier, traction motors (usually

with four or six axles), and a control system consisting of the engine governor and electrical

and/or electronic components, including switchgear, rectifiers and other components, which

control or modify the electrical supply to the traction motors. In the most elementary case, the

generator may be directly connected to the motors with only very simple switchgear.

In a diesel–electric locomotive, the diesel engine drives either an electrical DC

generator (generally, less than 3,000 horsepower (2,200 kW) net for traction), or an

electrical AC alternator-rectifier (generally 3,000 horsepower (2,200 kW) net or more for

traction), the output of which provides power to the traction motors that drive the locomotive.

There is no mechanical connection between the diesel engine and the wheels.

Besides steam- and diesel-powered locomotives, many trains operate solely on

electrical power. They get the electricity from a third rail, or electrical line, along the track.

Transformers transfer the voltage from the lines, and the electrical current drives the motors

(AC or DC) on the wheels.

8

1.4 History

Earliest recorded examples of an internal combustion engine for railway use included

a prototype designed by William Dent Priestman, which was examined by Sir William

Thomson in 1888 who described it as a "[Priestman oil engine] mounted upon a truck which

is worked on a temporary line of rails to show the adaptation of a petroleum engine for

locomotive purposes." .[3][4] In 1894, a 20 h.p. two axle machine built by Priestman

Brothers was used on the Hull Docks.[5][6] In 1896 an oil-engined railway locomotive was

built for the Royal Arsenal, Woolwich, England, in 1896, using an engine designed

by Herbert Akroyd Stuart.[7] It was not, strictly, a diesel because it used a hot bulb

engine (also known as a semi-diesel) but it was the precursor of the diesel

Following the expiration of Dr. Rudolf Diesel's patent in 1912, his engine design was

successfully applied to marine propulsion and stationary applications. However, the

massiveness and poor power-to-weight ratio of these early engines made them unsuitable for

propelling land-based vehicles. Therefore, the engine's potential as a railroad prime mover

was not initially recognized.[8] This changed as development reduced the size and weight of

the engine.

The world's first diesel-powered locomotive was operated in the summer of 1912 on

the Winterthur–Romanshorn railroad in Switzerland, but was not a commercial success.[9] In

1906, Rudolf Diesel, Adolf Klose and the steam and Diesel engine manufacturer Gebrüder

Sulzer founded Diesel-Sulzer-Klose GmbH to manufacture diesel-powered locomotives.

Sulzer had been manufacturing Diesel engines since 1898. The Prussian State Railways

ordered a diesel locomotive from the company in 1909, and after test runs between

Winterthur and Romanshorn the diesel–mechanical locomotive was delivered in Berlin in

September 1912. During further test runs in 1913 several problems were found. After the

First World War broke out in 1914, all further trials were stopped. The locomotive weight

was 95 tonnes and the power was 883 kW with a maximum speed of 100 km/h.[10] Small

numbers of prototype diesel locomotives were produced in a number of countries through the

mid-1920s.

General Electric (GE) entered the railcar market in the early twentieth century,

as Thomas Edison possessed a patent on the electric locomotive, his design actually being a

type of electrically propelled railcar.[12] GE built its first electric locomotive prototype in

1895. However, high electrification costs caused GE to turn its attention to Diesel power to

9

provide electricity for electric railcars. Problems related to co-coordinating the Diesel engine

and electric motor were immediately encountered, primarily due to limitations of the Ward

Leonard electric elevator drive system that had been chosen

In 1917–18, GE produced three experimental diesel–electric locomotives using Lemp's

control design, the first known to be built in the United States.[14] Following this

development, the 1923 Kaufman Act banned steam locomotives from New York

City because of severe pollution problems. The response to this law was to electrify high-

traffic rail lines. However, electrification was uneconomical to apply to lower-traffic areas.

The first regular use of diesel–electric locomotives was in switching (shunter)

applications. General Electric produced several small switching locomotives in the 1930s (the

famous "44-tonner" switcher was introduced in 1940) Westinghouse Electric and Baldwin

collaborated to build switching locomotives starting in 1929. However, the Great

Depressioncurtailed demand for Westinghouse's electrical equipment, and they stopped

building locomotives internally, opting to supply electrical parts instead

Early diesel locomotives and railcars in Asia

Japan

In Japan, since the 1920s, some petrol-electric railcars were produced. The first

diesel–electric traction and the first air-streamed vehicles on Japanese rails were the two

DMU3s of class Kiha 43000. Japan's first series of diesel locomotives was class DD50 twin

locomotives, developed since 1950 and in service since 1953.

China

One of the first home developed diesel vehicles of China was the DMU Dongfeng ,

produced in 1958 by CSR Sifang. Series production of China's first diesel locomotive class,

the DFH 1, began in 1964 following construction of a prototype in 1959.

A system which causes the propulsion of vehicle in which tractive or driving force is

obtained from various devices such as diesel engine drives, steam engine

drives,electric motors, etc. is called as traction system. ... This traction power can be diesel,

steam or electric power

The cost of electronic devices in a modern locomotive can be up to 50% of the cost of the

vehicle. Electric traction allows the use of regenerative braking, in which the motors are used

10

as brakes and become generators that transforms the motion of the train into electrical power

that is then fed back into the lines.

Series-wound DC motors. That means current flows through the armature, then

through the fields. They have high starting torque, favorable for starting a train. Nowadays

the trend is toward AC motors, typically a 3-phase induction motordriven by a DC->AC

inverter control.

The ignition of diesel fuel pushes pistons connected to an electric generator. The

resulting electricity powers motors connected to the wheels of the locomotive. A “diesel”

internal combustion engine uses the heat generated from the compression of air during the

upward cycles of the stroke to ignite the fuel.

11

Chapter-2

2.1 Block diagram of diesel electric

(a)

(b)

Fig:2.1 a,b (Block diagram of diesel electric )

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2.2 Basic structure of LOCOMOTIVE

Fig 2.2 (Basic structure of LOCOMOTIVE)

The Electro-Motive GT46PAC diesel-electric locomotive is equipped with a

turbocharged 16 cylinder diesel engine, which drives the traction alternator. (The traction

alternator is an important component of the main generator assembly.) The traction alternator

converts diesel engine mechanical power into alternating current electrical power. Internal

rectifier banks in the main generator assembly convert traction alternator output alternating

current to direct current. Rectified DC power produced by the traction alternator is distributed

through the DC link to DC/AC inverters in the Traction Control (TC) cabinet. Based on

inputs from the locomotive computer (EM2000), traction inverters supply 3-phase AC power

to four traction motors. The EM2000 responds to input signals from operating controls and

feedback signals from the power equipment. The traction control converter (TCC) is an

electrical device that can convert AC to DC and invert DC into AC (traction power). The

terms converter and inverter are used interchangeably in this manual. Each traction motor is

13

geared directly, with a single pinion, to a pair of driving wheels. The maximum speed of the

locomotive is set by locomotive gear ratio (ratio of traction motor revolutions to wheel

revolutions) and wheel size. Although each GT46PAC locomotive is an independent power

source, a number of locomotives may be combined in a multiple-unit (MU) tandem to

increase total load capacity. The locomotives in tandem may be equipped with either AC or

DC traction motors. Operating control functions are trainlined through a 27-conductor MU

cable. This enables the lead unit to simultaneously control other locomotives in tandem

14

Chapter- 3

3. Power Distribution system in locomotives

Supply system

The diesel engine is the source of locomotive power, when the engine is running it

directly drives three electrical generators:

1. Main generator (traction alternator)

2. Companion alternator

3. Auxiliary generator

3.1 Main generator (traction alternator)

The main generator (traction alternator) rotates at engine speed generating AC

power. Rectifiers are covered within the generator assembly. The rectifiers convert the

AC power to DC, and the DC output is applied to DC link. Switch gear and contractors

supply DC voltage to traction inverter circuits. The traction inverters convert the DC link

voltage to 3-phase AC power for the traction motors. There are two separate computers

TCC1 and TCC2 which control the traction motors by varying the voltage and frequency

which is fed to traction motors to get the proper torque and speed i.e., the output from

traction motors.

3.2 Companion alternator

The companion alternator is directly coupled to the traction alternator and is

within the main generator assembly itself. Output is utilized for the following:

• To excite the main generator (traction alternator) field.

• To drive the two rectifier cooling fan motors.

• To drive the inertial blower motors.

• To drive the traction inverter blowers.

• Various transducers and control devices.

15

3.3 Auxiliary generator

The auxiliary generator is driven by engine gear train. The output of aux. Gen. is

converted to74V DC in a rectifier &output from the rectifier is utilized for the following:

The auxiliary generator is driven by engine gear train. The output of aux. Gen. is

converted to74V DC in a rectifier &output from the rectifier is utilized for the following:

• To excite the companion alternator fields.

• Control systems.

• Battery charging.

• F. P. Motor.

• Turbo charger soak-back pump.

• Lighting and Misc. equipment.

The AC auxiliary Generator consists of a pilot exciter assembly and a three phase AC

Auxiliary Generator Field and armature assembly. The pilot exciter assembly consists of a

Stationary field, a rotating armature and rotating rectifier assembly. The AC Auxiliary

16

Generator has a rotating field and stationary armature. The pilot exciter rotating armature and

rotating rectifier assembly and the AC Auxiliary Generator rotating field are installed on a

common shaft. During start up, residual magnetism of the pilot exciter stationary field

induces voltage on the pilot exciter rotating armature. This AC voltage is rectified by the pilot

exciter rectifier assembly and applied to the AC Auxiliary Generator rotating field. This

rotating field induces voltage in the AC auxiliary generator stationary armature

(stator). The small AC output voltage of the auxiliary generator is applied to the DVR

(Digital Voltage Regulator Module).

The Low AC Signal is used by DVR to determine if the Aux. Generator is turning, if it does,

DVR will allow current from the batteries to flow in the exciter field of the Aux. Generator in

order to produce the 3 phase 55V AC output.

Model – 5A – 8147

Output – 18 KW

The Aux. Generator supplies voltage to the 2 GTO power supplies, panel mounted

module FCD (Firing control driver) and also to the full wave 3 phase rectifier (Battery

Charger) assembly to obtain 74V DC for battery charging, companion alternator excitation

and low voltage DC control power.

3.4 DC link voltage

During motoring the DC output from the main generator is called the DC link

voltage & is supplied to traction inverters.

DC link voltage varies with throttle position from 600 V DC to 2600 V DC at 8 th notch.

There is one traction inverter for each set of three parallel traction motors. The

two traction inverters TCC1 and TCC2 invert the DC link voltage in to variable voltage

and variable frequency 3 phase AC voltage. Both inverters are in turn controlled by

EM2000 computer.

3.5 Dynamic braking

During dynamic braking the energy of the moving train is transmitted into rotating

energy in the Traction motors. AC supply generated by all TMs will be fed back to

traction inverters TCC1 and TCC2 and is converted to DC. The converted DC supply is

now fed to dynamic braking grids which dissipate the electrical power in the form of the

17

heat. This loss of energy causes train to slow down. EM2000 maintains the braking

efforts required by the driver.

3.6 EM2000 computer

Both inverters are directly controlled by EM 2000 locomotive control computer,

which displays control system information on the screen. Most control and protective

functions are programmed into the EM2000 computer that monitors critical functions in

the locomotive power system provides a display message if a fault occurs. For serious

faults the EM 2000 also sounds the alarm bell and & takes corrective action.

Fig 3.6( single line diagram )

18

Chapter-4

4. ELECTRICAL CONTROL CABINETS

4.1.1 ELECTRICAL CONTROL CABINET # 1 This cabinet located at the back side of

the driver cab with the display to the front of ECC1. It houses some of the electrical and

electronic equipments needed to control the locomotive.

These equipments include:-

i. Locomotive control computer (EM 2000).

ii. Panel mounted modules

(ASC, TLF, FCD, FCF, DVR).

iii. Braking contactors (B1, B2, B3, B4)

iv. DC Link transfer switch

v. SCR assembly

vi. GTO power supply (GTO PS1 & 2)

vii. Current and voltage transducers

viii. Contactors and Relays

ix. Ground Relay Circuitry

x. Various circuit resistances

xi. Diode input panels (DIP 30, 31 & 32)

xii. Power Distribution Panels (PDP)

xiii. Circuit breaker panel.

This cabinet is subjected to high voltages and

currents; hence it should not be opened without following proper safety precautions:

4.1.2 ELECTRICAL CONTROL CABINET #2: ECC2 is located in the underframe of the

locomotive between Truck 1 and the Fuel tank. It houses:

i. ST& STA contactors

ii. Battery charging assembly iii. Auxiliary Generator circuit breaker (250A)

iv. Terminal Board for connecting ECC2 components

to external system

v. DC link reactor core

4.1.3 ELECTRICAL CONTROL CABINET #3: It is located near the equipment rack. It is

also called AC cabinet. It contains:-

19

i. Radiator Fan contactors

ii. 300 Amps radiator fan fuses or circuit breakers

iii. Main Reservoir pressure transducer

iv. Diode input panel DIP 80

All the three electrical control cabinets are pressurized cabinets. It contains one 800

Amps starting fuse and Battery knife switch. The battery switch should be kept closed and

never opened when the loco is in cranked condition.

4.2 COMPUTERS CONTROL OF LOCOMOTIVE

The GM locomotives are equipped with four interrelated computers to provide

electronic control of the various functions involved in locomotive operation. These

individual computers are:

1. The locomotive control computer, designated as EM2000.

i. The primary control system device is the EM 2000 locomotive control computer

(LCC).

ii. The locomotive operating controls provide inputs to the control computer, which

then directs electrical power equipment and the diesel engine to operate within the

constraints of the power and brake requirements.

iii. The EM 2000 exerts over all control over the other computers. Thus the other

three computers are is some way dependent on the EM 2000.

2. The Knorr CCB computer -This controls the air brake system based on control inputs

from the electrical brake valve and feedback from the active brake elements.

3. The Siemens SIBAS 16 computers- (02 Nos)

i. The EM 2000 manages the entire traction system through 02 Siemens SIBAS 16

computers and the traction control converters (TCC1, TCC2).

ii. SIBAS 16 monitors feedback signals and protective functions for each Traction

Control converters(TCC1, TCC2).

iii. The EM 2000 locomotive computer controls the main locomotive functions based

on inputs from the two traction control computers SIBAS 16.

iv. Each SIBAS 16 uses an Intel 8086 microprocessor with an Ultra-Violet Erasable

/Programmable Read Only Memory (UVEPROM).

20

Fig 4.3 (block diagram of computer control)

EM2000 Computer interaction

4.4 The EM2000 locomotive computer

1. The EM2000 locomotive computer controls-

• Generation of traction.

• Brake reference signals.

• Display/Diagnostic System (computer display).

• Locomotive Cooling System - cooling fans, radiator shutters.

• Diesel Engine - governor speed settings, turbo. lube pump, fuel pump.

• Engine Starting Circuit.

• Dynamic Brake System -braking contactors/braking effort.

• Excitation - monitors companion alternator (CA6B) output and controls main

generator excitation.

• Vigilance and wheel flange lubrication systems.

2. All communication with EM 2000 is through the key board on the display panel.

3. The microprocessor display panel is made of 6 line 40 columns vacuum fluorescent

display with a 16-button feedback key pad.

The display panel combined with loco control computer is referred as to display

diagnostic system. Thus the display diagnostic system is an interactive device that

provides an interface between EM 2000-control computer and the driver.

21

5. The computer provides massage for driver on the screen indicating loco control,

maintenance and trouble shooting function.

6. The computer is shaving four function keys F1, F2, F3 & F4 which indicates to cutout

traction motor or truck, reset a fault or request more information about other stored

data.

7. The display screen displays crew messages under normal operating conditions as well

as problems occur on loco such as:

♦ Engine speed up for low water temperature.

♦ Loco is not set up for the requested mode of operation.

♦ Power is limited.

♦ Some piece of equipment or system has failed and protective function is active.

8. Data can be downloaded.

22

Chapter-5

MAJOR ELECTRICAL EQUIPMENTS OF LOCOMOTIVES

The GM locomotive equipped with the following special features equipments in

constitutional aspect-

5.1 Main Alternator

No of pole : 10

Terminal Voltage : 1075 V

Speed : 1050 RPM

Rated current : 1998A-3600 A

Output : 2083 KW

The main alternator TA10102 is a 3-phase, 10 pole, 90 slots machine equipped with two

independent and interwoven sets of stator winding.

The main alternator construction is such that it is basically two alternators in one -

two sets of stator windings, permanently connected in series, work with a rotating field

common to both the windings in order to provide higher alternator output voltage, which is a

basic requirement of a low current high voltage alternator used on AC-AC locomotives. The

diesel engine drives the main alternator. The main alternator converts the mechanical power

of diesel engine into electrical power. The internal rectifier bank of the main alternator

converts alternating current into direct current there by providing a DC power output. The

DC power output from the main alternator is called the DC link voltage and is applied to the

traction inverters. DC link voltage varies with the engine speed from 600 V DC at idle to

2600 V DC at full speed. The inverter changes DC into variable AC power Alternator and

Traction Motor Blower

The Main Alternator Blower and Traction Motor Blower share a common housing

mounted on the front side of the auxiliary generator. Although both the blowers are

mounted on the auxiliary generator shaft an internal partition separates the two blower

portions. Air is drawn from the central air compartment into the alternator blower close to

the auxiliary generator and pass through a duct to the main alternator air box. Air from

alternator blower first cools the main alternator rectifier banks then passes internally

through the alternator and companion alternator to the engine room. This creates a slight

positive pressure to keep the dirt from entering the engine room.

23

Fig 5.1 ( main generator of diesel electric locomotive)

fig 5.1.2 ( curve voltage between current )

24

5.2 Companion Alternator

Companion alternator is a three phase AC steady state alternator of 250 kVA

rating, which is physically connected but electrically independent of the main alternator.

The companion alternator rotor field is excited directly by auxiliary supply of the

locomotive. It receives the excitation current from the auxiliary alternator through a pair

of slip rings, which are located adjacent to the slip rings of the main alternator.

The companion alternator develops power whenever the diesel engine is running. The

output voltage is directly proportional to the speed of rotation but varies to some extent

with change in alternator temperature and load. It is used for excitation of the main

alternator as well as for supply to Inertial (dustbin) blower, TCC1 and TCC2 blower

motor, TCC electronic blower, 55- 220 V AC for radiator fans and various control

circuits. An AC auxiliary alternator of 18 kW rating is used for meeting the auxiliary and

control system load.

The companion Alternator is physically connected but Electrically independent of

the Traction Alternator. The Companion Alternator field (rotating field) is excited by a

low voltage current output from Aux. Generator through a pair of slip rings adjacent to

the slip rings of the main alternator. The 3 phase AC output of the Companion Alternator

coming from the stationary armature (stator) is connected to a terminal board on the left

bottom of the Companion Alternator.

Type – CA 6B

Power – 250KVA at 0.8 PF.

Voltage – 45-220V 3 Ph AC.

Max. Frequency – 120 Cycles/Sec at 900 rpm.

Max. Current – 600 amps.

Brush grade – AY.

No. of Brushes – 4 (+ 2 Nos. –ve 2 Nos.)Condemning

Length – 38mm.

Fig (companion alternator )

25

5.3 Inertial Blower (Dustbin Blower)

Outside air is cleaned by Inertial (dustbin) Blower, before it enters central air

cabinet. In the Inertial Blower there are two inertial filter panels, one mounted on either

side of the locomotive. Outside air is drawn rapidly through the tubes which contains

specially designed vanes that induce a spinning motion to the contaminated incoming air.

Dirt and dust particles, because they are heavier than air are thrown to the outer wall of

the tube and carried to the bleed duct where it is removed by the scavenging action of the

Inertial blower and expelled through the roof of the locomotive. The resulting clean air

continues on through the smaller diameter portion of the tube where the air is again

caused to swirl by internal vanes. The particles are carried to the bleed duct and the

resulting clean air enters the central air compartment.

Model – DC Series Motor.

No. of Poles – 4

Capacity – 36 HP Brush Condemn Length – 25.4 mm (1”)

Each Dynamic Brake Grid cooling blower assembly consists of a 48” 10 blade fan powered

by a series wound DC motor. During Dynamic Braking the locomotive Traction Motors

operate as Generators supplying AC power to inverters. The inverters convert AC power into

DC voltage and supply back to the DC link. The DC link is connected across the grids

through contactors B1, B2, B3 & B4 and the Braking energy is dissipated as heat. A portion

of the electrical grid is used to power grid blower motor (36 HP).To dissipate grid heat to

atmosphere.

5.4 RADIATOR COOLING FAN MOTORS:

These motors are of inverted squirrel cage induction type and are an integral part of

the cooling fan assembly. The term inverted indicates that they differ from the conventional

squirrel cage motor in that the rotor is located outside the stator. Two 52” Cooling Fans (8

blades) which operate independently are located at the hood under the radiators and blow the

cooling air upwards through the radiator cores. They are numbered 1 and 2 with No. 1 close

to the cab.

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5.5 BATTERY

The locomotive is fitted with 500 A lead acid batteries. Each loco contains 8 batteries

each having 4 cells. These batteries supply power during cranking for the cranking motors

and the low voltage control circuit.

SCHEDULES:

1. Clean the batteries and blow with compressed air.

2. Visually examine the batteries for any terminal cracks, cable overheating marks, any

leakage.

3. Remove the vent plugs and clean properly.

4. Record cell voltage (2-2.2V), specify gravity (1.40-1.60), cell temperature (27-38C) and

electrolyte level (45 +/-5mm).

5. Ensure tightness of inter connection cables.

6.Ensure that batteries are properly packed in the battery box and there is no rubbing of

cables.

Note:

Work on Removed Batteries:-

1. In case any cell is weak, the battery to be removed and new/reconditioned battery to be

provided. The removed battery to be reconditioned as per MIS.

2. Whenever batteries are separately charged, ensure that cell temperature does not increase

beyond 45 0C

3. Ensure proper electrolyte level during charging.

4. Ensure proper setting of charging current and voltage.

5. Keep the batteries clean & dry.

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5.6 AC Traction Motors

Rated Power

425 kW

Maximum rotational speed 3320 rpm

Max. current rating 350 A

Application WDP4 and WDG4/ WDP4D

Customer Indian Railw ays (Diesel Locomotive Works)

A system which causes the propulsion of vehicle in which tractive or driving force is

obtained from various devices such as diesel engine drives, steam engine drives,

electric motors, etc. is called as traction system. ... This traction power can be diesel, steam

or electric power.

Series-wound DC motors. That means current flows through the armature, then

through the fields. They have high starting torque, favorable for starting a train. Nowadays

the trend is toward AC motors, typically a 3-phase induction motor driven by a DC->AC

inverter control.

The ignition of diesel fuel pushes pistons connected to an electric generator. The

resulting electricity powers motors connected to the wheels of the locomotive. A “diesel”

internal combustion engine uses the heat generated from the compression of air during the

upward cycles of the stroke to ignite the fuel. Traction motor refers to a type of

electric motor. A traction motor is used to make rotation torque on a machine. It is usually

changed into a straight line motion. Traction motors are used in electrically powered rail

vehicles such as electric multiple units and electric locomotives.

Traction motor refers to a type of electric motor. A traction motor is used to make

rotation torque on a machine. It is usually changed into a straight line motion.Traction

motors are used in electrically powered rail vehicles such as electric multiple units and

electric locomotives.

AC-AC transmission has the advantage of high adhesion and high tractive

effort, maintenance free Siemens ITB – 2622 -0TA02 Three phase AC traction motors,

28

high reliability and availability and higher energy efficiency. A specialty of this motor is

that there is no separate stator frame resulting in reduction of weight. In braking mode,

the three-phase motors act as generators and power is fed back to the DC link via the two

inverters.

Fig 5.6 (Traction motor mounting on axles )

Fig 5.6.2 (Traction motor)

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5.6.2 Traction motor run test

1. All of first check the IR of assemble motor and record .

2. Connect to the DC rectifier of traction motor .

3. First ,motor run at 40V . current should not be more than 50A and speed should be

600rpm & run at 30 min .

4. Change the motor supply voltage 10 V and at each changes run 30 min . and at each

changes note the current and note the temperature of PI & CI .

5. At the end , motor should run at half hour .

6. In every changes temperature of CI and PI will be 80 centigrade not more than .

7. Motor should run 160 V for five min .the speed of motor should be 1200rpm to 2275

rpm.

8. Check the last RI of motor and record .

5.7 Traction Motor Blower

The Traction Motor Blower is mounted on the auxiliary generator, supplies air for

traction motor cooling, generator pit aspirator operation, main electrical cabinet

pressurisation and traction computer cooling. Air is drawn through a movable inlet guide

vane through the blower, and delivered into a duct to the traction motors. A portion of this

air is diverted through a set of filters for delivery to the computer module portion of

traction inverter cabinets for module cooling. Another set of filters cleans the air used to

pressurise the main electrical cabinet.

5.8 TCC1 and TCC2 Inverters

The locomotive has two inverters TCC1 and TCC2. The output converter, a pulse

width modulated (PWM) inverter, is responsible for providing the variable frequency and

the variable terminal voltage for the three-phase motor. The main alternator feeds

electrical power to the DC link via two series connected diode rectifiers. Two identical

PWM inverters TCC1 and TCC2 with GTO and their capacitors are connected electrically

to the DC link via isolating switches. There is one traction inverter for each parallel set of

three traction motors, which are responsible for supplying power to them. A protective

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circuit based on GTO is connected to the DC link to protect the inverters against any

over- voltages. The TCC blower defuses heat produced by losses generated in TCC.

5.9 TCC Blower

An electronic blower in each TCC cabinet driven by its own 3-phase AC motor

draws the air from central air compartment in across the modules and expels it across the

R2 snubber resistor. This air is used for cooling and pressurising in some parts of the

inverter cabinet. This air keeps dirt from contaminating areas containing DC

linkcapacitors, gate units and traction computers. The TCC blower motor is a dual speed

3-phase AC induction motor. It operates as a series-Y wound machine for lower speed

(only low speed configuration is used on WDG4 locomotives). Power for the motors is

taken from the companion alternator through the main contacts of TCC1SS and TCC2SS.

EM2000 exercises control of the blower contactors at the request of the TCC via RS-485

serial link.

5.10 Radiator Cooling Fan Motors

Radiator Cooling Fan Motors are of the inverted squirrel cage induction type and

are integral part of the cooling fan assembly. Each cooling fan (total two per locomotive)

is driven by a two-speed AC motor, which in turn is powered by the companion

alternator. Cooling fans are powered through contactors, which are controlled by the

EM2000 program. Each fan motor circuit consists of one slow-speed and two fast-speed

contactors that are located in the AC cabinet.

5.11 Computer EM 2000

The WDG4 locomotive is equipped with a microprocessor based computer control

system. It provides fault detection of components and systems, it contains 'self tests' to aid

in trouble shooting locomotive faults. It has basic features like, significant reduction in

number of control modules, better fault detection of components, memory archive and

data snap shot. The microprocessor EM2000 is the locomotive control computer. EM

2000 utilises "Flash PROM" memory. It is a 32 bit computer based on Motorola 68020

microprocessor running at 16 MHz with a math co-processor communication through RS-

232 serial cable / port. EM 2000 controls the main locomotive functions based on inputs

from two traction computers. This system is equipped with a diagnostic display system in

the cab to provide an interface between the maintenance personnel and the computer. The

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computer is programmed to monitor and control locomotive traction power, record and

indicate faults that have been incorporated into EM 2000 system.

5.12 Computer Control Brake

The locomotive is equipped with KNORR/NYAB CCB (computer controlled

braking) 1.5 system. This system is an electro-pneumatic microprocessor based system

with 30A CDW type desktop controls. The overall purpose of using a computer

(microprocessor) to control the air brake system is to eliminate as many of the electrical

and mechanical devices as possible, there by reducing periodic maintenance, simplifying

trouble shooting, fault diagnostics etc. It allows greater reliability and flexibility for future

system upgrade.

5.13 Dynamic Brake

Each unit of the Dynamic Brake Grid Blower Assembly consists of fan assembly

powered by a 36 HP series wound DC motor. During dynamic braking, a portion of the

current (rectified DC) from the traction motors is shunted around one of the resistor grids

and used to power the grid blower motor. Air driven by the grid blower drives grid heat to

atmosphere.

5.16 Traction Control Computers

There are two SIBAS 16 traction control computers. Each computer is dedicated to one

inverter. SIBAS 16 is a 16-bit computer based on an INTEL 8086 microprocessor running at

5.6 MHz. The TCC receives data via RS-485 serial link from the locomotive computer

EM2000. The bi-directional bus carries data such as how much power for traction the TCC

must develop as well as other information to control activation of devices like blowers and

heaters. In addition to the RS-485 data, information constantly gets fed back into the TCC, to

monitor various things such as status of relays and temperature of various components,

voltages and currents. Based on this feed back data and information received via RS-485

serial link, the programs stored in the TCC work to drive the TCC as well as to protect it in

the event of faulty operating conditions. Radar

The locomotive is equipped with a K- BAND RADAR module. The mounting

location of radar under the cab of the locomotive near the end plate. This particular type

32

of RADAR system mounts at an angle of 37.5° with respect to the rail. It is particularly

susceptible to signal error as a result of inaccurate mounting.

5.17 Under Truck

The WDG4 locomotive is equipped with a high adhesion HTSC (High Tensile

Steel Cast) truck or bogie. The bogie assembly supports the weight of the locomotive and

provides the means for transmission of power to the rails. The HTSC bogie is designed as

a powered 'bolsterless unit'. Although the bogie or truck frame itself is rigid, the design

allows the end axles to move or "yaw" within the frame. This movement will allow the

wheels to position themselves tangent to the rails on curves for reduced wheel and rail

wear. Axles 1 and 3 can move or kink a little bit to negotiate a curve from 0-8 degree

deflection, increases the tractive effort and improves the rolling resistance.

Traction loads are transmitted from the truck or bogie to the locomotive under frame

through the carbody pivot pin assembly. Each bogie is equipped with three unidirectional AC

traction motors for better adhesion characteristics. The motors are geared to the driving axles,

which in turn apply rotational force to the rails through the wheels. The driving force is

transmitted to the bogie through tractive rod attached to the journal-bearing adapter in the

frame. From the truck / bogie frame the driving force is transmitted to the locomotive car

body through the car body pivot pin.

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CONCLUSION

I have completed my training from the DIESEL LOCOMOTIVE WORKSHOP,

LUCKNOW .I have observed many shop in the workshop I mainly performed my training in the

TRACTION GENRATOR SECTION.

In the locomotive workshop all the S.S.E & J.E. & SUPERVISIORS of all the shops

helped very much. Without his or her supervision I was not able to perform the training in all the

workshop. I am very grateful to him.

We have learned too much in the workshop, DIFFERENT TYPE OF WORKSHOP

TECHNOLOGY, TESTING OF THE PARTS OF THE LOCOMOTIVE AND THE PROPER

FUNCTIONING of the different locomotive part as an , Dynamic Brake Traction Control

Computers Main Alternator Auxillary alternator Companion Alternator Inertial Blower (Dustbin

Blower RADIATOR COOLING FAN MOTORS BATTERY Battery ,Traction Motors, Traction

Motor, Blower, TCC1 and TCC2 Inverters, Radiator Cooling Fan Motors, Computer Control

Brake, Dynamic Brake, Traction Control Computers .

34

REFRENCES

https://wikimedia.org.in

http://www.woodward.com/ApplicationsLocomotive.aspx

https://en.wikipedia.org/wiki/Turbocharger

https://www.dieselnet.com/tech/diesel_fi_ui.php

https://www.IRFCA.CO.IN

https://www.rdso.in

https://www.indianrailay.in

https://www.wikipedia.org

https://www.google.com