In India we are familiar to only on system of trains that is a locomotive leading the coaches (I say it a leading power system). This system is neither safe,fast nor efficient. For the replacement of this system few countries have introduced Train set System.
What are Trainsets?
Trainsets are just coaches having their own traction motors for each pair of wheels which are controlled by a controller system present in the first and/or last coach in the set.
Why they are fast?
It is quite simple to answer this. The individual traction motors makes the power distribution good so the momentum transfer from locomotive to coaches is not required hence the speed becomes good.
- Good Acceleration : Because they have individual traction motors they are good in acceleration.
- Safer than leading power system : The change in momentum is negligible when train stops or starts so there is low probability of shocks as well they derail (due to emergency braking) rarely.
Usage in India
They are currently used as EMUs,MEMUs,DEMUs,etc. They are proposed to be used in premium trains from 2020.