What is a three phase induction motor?

Answer 1

Induction motor is nothing but rotating transformer it works on principle of mutual induction , mainly induction motor consists of rotor and stator,stator is excited by three phase supply and rotor is shorted through resistances and slip rings. When ever stator is excited by three phase supply a rotating magnetic field running at synchronous speed is produced which in turn cuts the rotor winding causes flowing of current results in production of magnetic fields in rotor which having less than synchronous speed (slip speed), then the interaction of these stator and rotor magnetic fields produces a twisting moment in the rotor called synchronous speed

Answer 2

A three phase induction motor is a device in which the rotor rotates at speed slightly less than the synchronous speed. the difference between the synchronous speed and the rotor speed is called slip which ranges from 2-5%.

Answer 3

What is the question? Three phase motors are usually the choice for large motor and commercial applications. They usually operate on higher voltages which reduces associated costs of wiring and switchgear. These voltages are not available to the average homeowner. They are also cheaper than single phase motors. They use fewer parts and simpler windings. Commercial demand also affects the cost. The most important consideration in motor selection is power consumption, measured in watts. Three phase motors still consume watts to generate horsepower, so the basic difference is economic in nature.

Answer 4

Three phase supply can be connected with the help of following to the induction motor:

1. Directly with M.C.B.

2. Directly with M.P.C.B.

3. Through Direct On-line Starter.

4. Through Star-Delta Stater.

5. Through Soft Stater.

6. Through A.C. Drive.

Answer 5

Normally you use a motor starter or contactor. There are manual and electric starters available. With a starter it closes all three legs of power at the same time to the individual phases. Other options are VFD's and Soft starts.