Electric traction systems use electrical power to provide traction for railways, trams, and trolleys. The key components of an electric traction system include traction substations that transform and rectify power, overhead wiring to transmit current, pantographs or trolley poles on vehicles to collect current, track to complete the circuit, and traction motors on vehicles powered by the collected current. Electric traction systems offer advantages over other systems like steam engines in terms of lower operating costs, lack of smoke and gas emissions, lower maintenance costs, faster starting and acceleration due to high starting torque of DC and AC series motors used, and regenerative braking that feeds energy back into the system.

1. ELECTRIC
TRACTION SYSTEM

2. CONTENTS
INTRODUCTION
MAJOR COMPONENTS
REQUIREMENT OF AN IDEAL TRACTION SYSTEM
OPERATION
WHY ELECTRIC TRACTION SYSTEM??
LEADING TRACTION SYSTEMS AROUND THE WORLD
PRESENT STATUS
ELECTRIC TRACTION SYSTEM

3. INTRODUCTION
 Driving forward of vehicle is called traction and the system, which employs this
type of mechanism is called Traction system.
 Classified broadly into groups namely:
 Non-Electric traction system:
Traction system which do not involve the use of electricity such as steam engine
drive, IC engine drive etc .
 Electric traction system.
The system which use electrical power for traction system i.e. for railways,
trams, trolleys, etc. is called electrical traction.

4. ELECTRICAL TRACTION SYSTEM
Electric traction is meant for locomotion in which the driving (tractive) force
is obtained from electric motors(called as traction motors).
BACKGROUND
The first known electric locomotive was built in 1837 by
chemist Robert Davidson of Scotland. It was powered by
galvanic cells (batteries).
In 1880, Thomas Edison built a small electrical railway,
using a dynamo as the motor and the rails as the current-
carrying medium.

5. TYPES OF ELECTRIC TRACTION SYSTEM
POPULARLY PRACTISED VOLTAGE
25KV,50HZ 1500V &3000V DC
Multisystem:
1.5kv DC, 3kv DC , 1.5kv AC, 25kv AC

6. MAJOR COMPONENTS
1-TRACTION SUBSTATION 2-OVERHEAD WIRING
3-CURRENT COLLECTOR 4-TRACK
5-TRACTION SYSTEM (VEHICLE)

7. MAJOR COMPONENTS CNTD…
1-TRACTION SUBSTATION
 Switchgear
 AC Circuit Breaker
 DC Circuit Breaker
 Transformers & Rectifiers
 Transfer to required voltage level and Rectification.
 Control and Monitoring unit
Substation spacing
 Typically 4km to 15km
 Depends on a number of factors including
• Train loads
• Track grades
• Losses
• Over head wiring types

8. TRACTION
SUBSTATION

9. 2-OVERHEAD WIRING
• Contact wire-suspended with minimum of sag so that
contact between the trolley wire and current collector can be
maintained at higher speeds.
• The wire is supported by another wire called as catenary.
• Two different types of catenary construction can be used-
 single catenary:
One or two contact wires supported by a catenary wire
 compound catenary
A main catenary supports an auxiliary catenary, which in
turn supports the contact wire.
MAJOR COMPONENTS CNTD…

10. Trolley collector
BOW COLLECTOR
PANTOGRAPH
COLLECTOR
3-CURRENT COLLECTOR

11. MAJOR COMPONENTS CNTD…
4-TRACK

12. 5-TRACTION SYSTEM ( VEHICLE)
 CIRCUIT BREAKERS: To disconnect the engine (motor)
in case of some fault
 TRANSFORMER: Tap changing transformer is installed
in the locomotive for stepping down the voltage according
to the requirement of the traction motor.
 ON LOAD TAP CHANGER: Used for varying the
output voltage for controlling the speed of motor.
 RECTIFIER AND SMOOTH REACTORS:
Semiconductor rectifier are used for AC to DC power
conversion. Smooth reactors eliminates ripples found on
output side of rectifier.
MAJOR COMPONENTS CNTD…

13. TRACTION SYSTEM ( VEHICLE) CNTD…..
TRACTION MOTORS:
 D.C series motors:
 Single phase A.C series motors:
 Easier construction
 Three-phase Induction motors
 High torque at low speeds & low torque at high speeds.
 Easy speed control
 Speed of an ac series motor may be controlled efficiently by taps on a transformer
 Robust construction
 Trouble free operation
 Less maintenance requirement
 complicated speed control systems
 Not suitable for traction work
 Automatic regeneration is the main advantage of this motor

14. CONTROL UNIT:
 REMOTE CONTROL CENTER(RCC):
 From substation/ Traffic control division
 Nerves system for traction system.
 3 Pair of conductors from and to RCC
 SYSTEM CONTROL CENTER:
 Master controller ,From the vehicle
 Enable output from the vehicle
operator’s commands
 Forward, reverse, powering, neutral and
braking, to the electric control device

15. REQUIREMENT OF IDEAL TRACTION
SYSTEM
 Thewearcausedonthetrackshouldbeminimum.
 Maximumtraction effortsshouldbeexertion atstartinginordertohaverapid
acceleration.
 Capacityofwithstanding voltagefluctuation andtemporaryinterruption of
supply.
 Brakingshouldbepossible withoutexcessive wearonthebrush.
 Parallel running usually more thanonemotor(twoorfour)shouldbepossible.

16. OPERATION OF TRACTION SYSTEM

17. [1] Traction transformer
[3] Traction control
[5] Traction motor
[7] Auxiliary converter
[9] Energy storage
[2] Traction convertor
[4] Control and Monitoring System
[6] Diesel engine generator
[8] Battery charger

18. BRAKING OF ELECTRIC TRACTION
MOTOR
BRAKING CAN BE ACHIEVED BY TWO METHODS-
1.MECHANICAL BRAKING
2.ELECTRICAL BRAKING
ELECTRICAL BRAKING very superior then MECHANICAL BRAKING
ELECTRICAL BRAKING
CLASSIFIED INTO THREE CATEGORIES-
1.PLUGGING
2.RHEOSTATIC BRAKING
3.REGENERATION
1.PLUGGING- Plugging is applied by changing phase sequence of synchronous or
induction motors.
2.RHEOSTATIC BRAKING- Connection are made changed from power configuration to
brake configuration and resistor are inserted in motor circuit.
3.REGENERATIVE BRAKING- Motors become generators and feed resulting current
back into supply system.. Return current, generated during braking, to the supply system for use by
other trains

19. WHY ELECTRIC TRACTION SYSTEM???
Cheapness: Lowoperationcost
Cleanliness: Smokeandgasfree
Maintenancecost: 50%less then othersteamengines
Startingtime and speed:Withoutlossoftime.
Highstartingtorque:UsesofD.C&A.Cseriesmotor-veryhighstartingtorque.
Braking : Regenerativebreakingisusedwhichfeedsbackenergy.
Savinginhighgradecoal:Savingofnon-renewableenergysource.

20. LEADING TRACTION SYSTEMS AROUND THE WORLD
 Magnetic traction (maglev).
 Speeds up to 581 kmph have been successfully
tested.
 Shinkansen (bullet train) uses electrical system,
offering high acceleration and deceleration.
 It employs an automatic train control system
(atc),which controls all train movements ,track
,station and schedule are networked and
computerized.
 Software Analysis and Modelling (etrax)

21.  LONGEST ELECTRIC TRACTION SYSTEM
IN RUSSIA
 OUR NEIGHBOURS CHINA AND INDIA ARE
IN 3RD &4 TH POSITION.
 Don’t we bear the potential??
Yes, of course!!!!!
PRESENT
STATUS

22. Past electric trolly bus
Present status of
electric trolly bus
Started in 1975 - gift by the government of the People's Republic of China.
13km - 10,000 passengers daily
Route: Tripureshwor Ktm – Suryabinayak Bhaktapur
Tripureshwor – Koteshwor
NEPA
L
Suspended in 2008
Permanently dismissed in 2009 by KMC due to chronic unprofitability.

23. MAY 13, 2016 STARTED

24. THANK
YOU