Explain Squirrel- cage rotor
Squirrel- cage rotor having of a slotted laminated core of sheet-steel. The slots of the rotor are not always parallel to the slots on the stator, but they are given a twist called as skew. (Skew decreases noise, eliminates cogging and enhances the starting torque). The windings are placed in the slots. Every slot carries a thick copper or aluminum bar. These bars are short-circuited on either end by a solid copper or aluminum ring known as end-ring. Most of the 3-phase induction motors are of squirrel cage type, due to its rotor is simple and rugged in construction and is cheaper.