The Traction system was started in India under the supervision of the private firms. Later on it was undertaken by the Government of India. The first Traction System was DC system.
There are four types of Traction Systems:
- DC System
- Single Phase AC system
- 3 Phase AC system
- Composite System
- Kando system
- Single phase AC to DC system.
1. DC SYSTEM
In DC system ,DC series Motors are used to provides the necessary tractive Force. It was the earliest form of Traction system. It is usually used in 600 V,750 V,1500 V,3000 V. It consists of a single phase overhead wire connections and which is further converted into three phase which is then provided to the input of the Rectifier circuit for converting it into DC supply. This DC input is given to the DC seried motor.
ADVANTAGE of DC series motor is that it have High Starting torque and easy speed control . It is more efficient then other motors used
DISADVANTAGE of DC motor is that it is incapable of Regenerative Braking
2. SINGLE PHASE AC SYSTEM
In AC systems , AC series motors is used. The single phase AC commutator motor is usually preferred. It consists of AC single phase overhead wire and single Phase AC motor. It is incapable of regenerative Braking. It is usually preferred for Main line services. IT uses low value of the frequency. Usually 16.66 Hz is used.
ADVANTAGE is that it does not require any additional convertor or the rectifier circuit.
DISADVANTAGE is it is incapable of regenerative Braking.
3. Three Phase AC system
It uses three phase induction motor for providing the necessary tractive effort. Three phase induction motor is capable of regenerative Braking. But there are several disadvantage sof three phase induction motore is that it have constant speed torque characteristics and low startingh torque.
- It uses the composite of single phase overhead wire and three phase induction motor.
- It is used in Hungary and many other italian countries.
SINGLE PHASE AC TO DC SYSTEM
- It is widely used in India. It consists of AC overhead wires and DC series motor.