How does a squirrel-cage rotor work in an induction motor?

In an induction motor, the squirrel-cage rotor is a robust and economical component designed to facilitate rotation through electromagnetic induction.1

The rotor consists of a core made of steel laminations featuring slots that house solid conductors. These conductors are short-circuited at both ends of the rotor by conducting end rings, forming a structure that resembles a squirrel cage. Because the conductors are shorted together, there is no requirement to insulate them from the iron core.1

The motor operates when the stator creates a rotating magnetic field that induces a voltage in the rotor conductors. This induced voltage drives electric current through the shorted bars, which, in turn, interacts with the magnetic field to produce the torque necessary for rotation. For smaller motors, the assembly is often an aluminum casting that includes the conductors, end rings, and a cooling fan, while larger motors typically use copper, aluminum, or brass bars welded or brazed to end rings.123