Induction Motor:

Previous explanations of the operation of an AC motor dealt along with induction motors. An induction motor is the most generally used AC motor in organizational applications since of its simplicity, rugged construction, and associatively low manufacturing costs. The purpose in which the induction motor has these features is since the rotor is a self-contained unit, along with no external connections.   This category of motor derives its name from the actual fact in which AC currents are induced into the rotor through a rotating magnetic field.

The induction motor rotor that was show in the figure is made of a laminated cylinder along with slots in its surface. Windings in the slots are one of two types.  The most generally used is the "squirrel-cage" rotor.  That rotor is made of heavy copper bars which are linked at every end through a metal ring made of copper or brass.  No insulation is needed among the core and the bars since of the low voltages induced within the rotor bars.   A size of the air gap among the rotor bars and stator windings must have to acquire the maximum field strength is small.

Figure: Squirrel-Cage Induction Rotor

Figure: Split-Phase Motor