The working principles and stator construction of the slip ring induction motor are exactly the same as that of the squirrel cage motor.
Slip ring induction motor rotor connection.
Instead of bars in this motor three windings are used.
This construction of the rotor is aimed at reducing the phase difference.
The major difference between squirrel cage rotor and wound type rotor is the presence of a slip ring in wound type rotor hence it is also called a slip ring rotor.
The three terminals of star connected rotor windings are brought out and are connected to the external resistors through the slip ring.
The rotor is wound for the same number of poles as that of the stator.
However the rotor construction of the slip ring motor is quite interesting.
The motor which employing the wound rotor is known as a slip ring induction motor or phase wound motor.
A wound rotor motor also known as slip ring rotor motor is a type of induction motor where the rotor windings are connected through slip rings to external resistance.
Adjusting the resistance allows control of the speed torque characteristic of the motor.