An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. Three-phase squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable and economical. Single-phase induction motors are used extensively for smaller loads, such as household appliances like fans. Although traditionally used in fixed-speed service, induction motors are increasingly being used with variable-frequency drives VFD in variable-speed service.
Three-Phase Induction Motor – Construction, Working, Types & Applications
Three Phase Induction Motor: Types, Working, and Applications
The steps began for the introduction of induction motor in the year Earlier it was made to run under 60 HZ power supply in This was made practically possible by Westinghouse. Later investigations have been conducted to work these type of motors under two-phase supply. The multi-phase supply produced much better advantages than single-phase. The disadvantage of one-phase is, it cannot self-start while the three-phase motor can self-start. The Three-phase IM can develop a Rotating magnetic field which makes it possible to self-start.
Non-Uniform magnetic field produces a non-uniform torque which makes the operation of the motor noisy, affect starting torque. A single phase induction motor consists of a single phase winding on the stator and a cage winding on the rotor. When a 1 phase supply is connected to the stator winding, a pulsating magnetic field is produced. In the pulsating field, the rotor does not rotate due to inertia. Therefore a single phase induction motor is not self-starting and requires some particular starting means.
Induction machines are the most frequently-used type of motor used in residential, commercial, and industrial settings so far. In an induction motor, the electric current in the rotor needed to produce torque is obtained via electromagnetic induction from the rotating magnetic field of the stator winding. An induction motor is a generally used AC electric motor.