- The rotor windings are star-connected like a three-phase star connected transformer.
- Rotor winding is present inside rotor drum. Rotor drum is placed on the motor shaft.
- Motor shaft carries three slip rings which are circular in shape and rotates at the same speed as that of the rotor. The rotor winding terminal is permanently connected to these slip rings.
- The slip rings are continuously in contact with three brushes which are stationary. In most of the time, external resistances is necessary to develop a high starting torque.
- Thus external resistance can be added to rotor resistances with the combination of slip rings and brushes. So rotor terminals are accessible to the user due to use of slip rings and brushes.
Wound rotor induction motor