Why are DC motors used in trains and not AC motors ?

1 Answer

Answer :

The reason is torque. torque is inversely proportional to speed..i.e when th knowe train comes to rest position to motion.. initial speed is zero..so it requires high starting torque for that we use D.C series type motor.. because of in this motor both armature and field coils are connected in series .hence at the initial stage maximum current will flow through field and armature coils then maximum torque is available at the intial condition.

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