What is the working principle of 3 phase induction motor?

The stator of an induction motor consists of a number of overlapping windings offset by an electrical angle of 120°. When the primary winding or stator is connected to a three phase alternating current supply, it establishes a rotating magnetic field which rotates at a synchronous speed.

Which starting method is best in three-phase induction motor?

Star Delta starter This is the most common form of starter used for three phase induction motors. It achieves an effective reduction of starting current by initially connecting the stator windings in star configuration which effectively places any two phases in series across the supply.

Which type of induction motor is best?

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.

What are the advantages of 3 phase induction motor?

Unlike synchronous motors, a 3 phase induction motor has a high starting torque, good speed regulation and reasonable overload capacity. An induction motor is a highly efficient machine with full load efficiency varying from 85 to 97 percent.

How does a 3 phase induction motor work?

• The 3-phase set of currents, each of equal magnitude and with a phase difference of 120o, flow in the stator windings and generate a rotating field will constant magnitude. The rotating magnetic field. • Consider a two-pole.

Why are the slots in a phase induction motor skewed?

The slots are not exactly made parallel to the axis of the shaft but are slotted a little skewed because this arrangement reduces magnetic humming noise and can avoid stalling of the motor. The stator of the motor consists of overlapping winding offset by an electrical angle of 120 o.

What are the different types of induction motors?

Types of Electric Motors 3-Phase induction machine construction • 3 stator windings (uniformly distributed as in a synchronous generator) • Two types of rotor: –Squirrel cage –Wound rotor (with slip rings) The rotating magnetic field

How does a rotor move in an induction motor?

The current-carrying rotor conductors are placed in the magnetic field produced by the stator. Consequently, a mechanical force acts on the rotor conductors. The sum of the mechanical forces on all the rotor conductors produces a torque which tends to move the rotor in the same direction as the rotating field.