1. ELECTRIC TRACTION SYSTEMS
Prepared By :

2. MOTIVATION Sheer size and roaring sound.
Use of electronics to bring down distance and time.
A fascination for electrical students
- Use of traction motors
- Speed Control
- Braking

3. TOPICS TO BE DISCUSSED
Traction system, its classification and nomenclature.
Power Supply in Electric Traction (AC and DC systems).
Traction motors used.
Control of traction motors.
Braking.

4. TRACTION SYSTEM, ITS CLASSIFICATION AND NOMENCLATURE

5. INTRODUCTION
Traction - locomotion on the rails (driving force - steam or electric drive)
Classification of Traction Systems:
> Non-Electric
> Electric
- receive electricity externally
- self contained locomotives

6. NOMENCLATURE IN INDIAN RAILWAYS
Name consists of four parts e.g. WDP2: Diesel-Electric Passenger train running on broad gauge
W/Y/Z
(Gauge type)
A/D
(Mode of traction)
P/G/M/S
(What for it is used)
2/4/6/2C
(Model No.)
A  AC Traction
D  Diesel-Electric
Traction (Not DC Traction)
P  Passenger
G  Goods
M Mixed (Passenger and Goods)
S  Shunting
W  B.G.
Y  M.G.
Z  N.G.

7. TYPES OF RAILWAY SERVICES
TYPES OF GAUGES USED
Type of Gauge
Gauge Width 1.
Standard Gauge or Broad Gauge (B.G)
1.676 m 2.
Meter Gauge (M.G)
1.0 m 3.
Narrow Gauge (N.G)
0.762 m 4.
Light Gauge (L.G)
0.610 m
TYPES OF RAILWAY SERVICES
Main line service
City service or urban service
Sub-urban service

8. SYSTEMS OF TRACK ELECTRI-FICATION
Direct current system
Single phase low frequency a.c system
Single phase high frequency a.c system
Three phase a.c system
Composite system
- Single phase to Three phase - Single Phase to Direct Current

9. POWER SUPPLY IN ELECTRIC TRACTION (AC AND DC SYSTEMS)

10. POWER SUPPLY IN ELECTRIC TRACTION
Conductor Rail System
Overhead System
Contact strips
Horn
Pantograph arm
Fig: Pantograph and its parts

11. OVERHEAD LINE CATENARY

12. TYPES OF OVERHEAD CATENARY

13. CONTROL OF TRACTION MOTORS

14. CONTROL OF DC TRACTION MOTORS
Rheostatic Control
Series-Parallel Control

15. CONTROL OF DC TRACTION MOTORS (Contd.)
Field Weakening Method
Diesel-Electric Locomotive Control

16. CONTROL OF AC INDUCTION MOTOR
Rheostatic Control
Pole-Changing Control
Cascade Control
Combination of Cascading and Pole-Changing Control

17. BRAKING OF TRACTION MOTORS

18. BRAKING Electrical Braking - Plugging - Rheostatic Braking
- Regenerative Braking
Mechanical Braking
- Compressed Air Brake
- Vacuum Brake
- Magnetic Track Brake

19. REGENERATIVE BRAKING

20. ADVANCED TRACTION SYSTEMS
Multiple Unit Traction System (EMU, DMU)
Driving force – from multiple units
EMU – suburban railway transport
Rheostatic Control

21. ANY QUESTIONS ??? CONCLUSION
Advanced technologies – Magnetic Levitation used for ultra high speed trains
Electric traction – economical, easy and safe
ANY QUESTIONS ???