The line side converter converts the a.c.voltage into D.C.Voltage and this D.C.Voltage is converted into 3 phase AC by inverter with variable frequency which powers AC traction motors. ... AC traction for locomotives is a major improvement over the old DC systems.
DC motor maintenance was very expensive and regeneration was also not possible. With 3 phase traction motor maintenance cost is reduced and prime objective of regeneration is also achieved.
For locomotive we are using two types of Traction Motors of rating 1150 KW & 850KW.And for EMU & MEMU motors upto 270KW.