What are the differences between AC and DC motor armature windings ???
The biggest difference between the armature windings or more correctly rotor windings (They are not normally called armature windings in AC motors) is how the windings are electrically connected to the outside world.
In conventional DC motors the connection is made though a commutator and brushes. This is done to reverse the magnetic polarity of the rotor so it will rotate inside the fix field of the stator.
I some DC motors like, stepper motors there is no electrical current in the rotor.
There are two types of AC motors – induction and synchronous.
In AC induction motors there is no physical electrical connection between the rotor and the outside world. The electrical current and resultant magnetic field is induced because of the rotating electrical field generated in the stator windings.
For synchronous AC motors the electrical current is supplied to the windings of the rotor though two or more slip rings.
For more information about motor design and construction
