Traction

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.)
W  B.G.
Y  M.G.
Z  N.G.
A  AC Traction
D  Diesel-Electric
Traction (Not DC Traction)
P  Passenger
G  Goods
M Mixed (Passenger and Goods)
S  Shunting

7. TYPES OF RAILWAY SERVICES
 Main line service
 City service or urban service
 Sub-urban service
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 GAUGES USED

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
Horn
Pantograph arm
Contact strips
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. CONCLUSION
• Advanced technologies – Magnetic
Levitation used for ultra high speed trains
• Electric traction – economical, easy and
safe
ANY QUESTIONS ???