ABSTRACT
This chapter explains the principle of operation of the different types of three-phase induction motors. It aims to understand how a rotating magnetic field is produced. The chapter describes the principle of operation of a three-phase induction motor. It addresses torque-speed and torque-slip characteristics for an induction motor. The induction motor is a three-phase alternating current motor and is the most widely used machine in industrial applications. In three-phase induction motors that are inherently self-starting, energy transfer is usually from the stator to either a wound rotor or a short-circuited squirrel cage rotor. Three-phase cage rotor induction motors are widely used in industrial drives because they are rugged, reliable and economical. In a three-phase induction motor, the magnetic field rotates and this has the advantage that no external electrical connections to the rotor need be made.
