Induction Machines

A motor with only a continuous set of armature winding is called an induction motor
Such motors are called induction machines because the rotor voltage is induced (which produces the rotor current and the rotor magnetic field) in the rotor wingdings rather than being physically connected by wires.The distinguishing feature of an induction motor is that no dc field current is required to run it.

The induction machine is by far the most common type of motor used in industrial, commercial and residential settings. The main reasons for its commonality in these arenas are that it is inexpensive and highly robust. Induction machines can be operated in either generation mode or as a motor (i.e. load). 

An induction motor always runs at speed less than synchronous speed. Because the rotating magnetic field produced in the stator will create flux in the rotor and hence will make the rotor to rotate. Due to the lagging of flux current in the rotor with flux current in the stator, the rotor will never reach its rotating magnetic field speed, i.e. the synchronous speed.

There are basically two types of induction motors. The types of induction motors depend upon the input supply. The single phase induction motor and three phase induction motor. Single phase induction motor is not a self-starting motor, and three phase induction motor is a self-starting motor.








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