Induction motor is the horse power of the industry since long time ago, because of its cost is cheep, construction and maintenance are simple. It comes from fractional horse power up to thousands of horse power. That is why.

Thanks

You are welcome

i know induction motor is a AC motor...if we supply DC means what is happening?

It will not rotate, and it might create short circuit, because the Dc current can not create a rotating magnetic field alone , it needs an other rotating field in order to establish torque in the rotor . and as you know that the Ac induction machine is a singly fed machine at the stater only, however the Dc machine there are two fields and the interaction between these two torques will create the circumferential torque which leads to rotate the rotor .

thanks Adel Aktaibi..if supply AC to DC motor ,it can rotate slow with in reverse direction but dc shut motor stand still....can you explain what is the reason for that?

could you please give more information, as I could not understand what happened. And , did you make this experiment ?

No i didn't make this experiment. My friends told me...so i ask how is this possible?

I don't know about further information about that

Refer the induction motor working.....only ac can provide an rotating magnetic field...if we provide dc instead of ac it will not create..and also it doesnt provide high torque

Induction motors are rugged in construction self starting, small in size less in weight , high efficiency low maintanance less accidents last but not least low cost for same power rating requirments which are required characterstics for industries.Thus 90% industrial drives are of induction motor.

I agree with Mr. Kinhal Sir... Even if it is single phase machine also, a small capacitor will make the motor run. Basically compact, rugged and cheap as said by Kinhal sir.

because 3-phase induction motors have Starting Torque (because in starting instant, stator and rotor rotating fields have same speed (synchronous speed) and angle between these two field is time-independent and torque is non-zero) and can start itself. synchronous motors has not starting torque because in starting instant, angle between stator and rotor rotating fields is time-dependent and torque is zero (rotor field is constant and stator field rotates at synchronous speed).

Thank you everyone who cleared my doubt

In three phase power system electric power delivery is constant, so power and torque ripples are very limited. IM don't need any rotor contact (commutator) - the power is delivered by rotational magnetic flux.

Widest power range: from 1W to 20 MW.

INduction motor is more commonly used for small applications as

Its construction is cheaper and it is more economical than other types. The technical reasons are already listed above by the others.

he AC induction motor is the dominant motor technology in use today, representing more than 90 percent of installed motor capacity.

Induction motors are available in single-phase and polyphase configurations, in sizes ranging from fractions of a horsepower (hp) to tens of thousands of a horsepower (hp). Induction motors may run at fixed speeds -- most commonly 900, 1,200, 1,800, or 3,600 rpm -- or be equipped with an adjustable-speed drive.

The most commonly used AC motors by far have a squirrel-cage configuration. This kind of ac motor is so named because of the shape of the rotor bar structure. And wound-rotor models, in which coils of wire turn the rotor windings, are also available.

These are expensive but offer greater control of the motor's performance characteristics. So these ac motors are most often used for special torque and acceleration applications and for adjustable-speed applications.

The major choice facing motor specifiers is whether or not to select a premium-efficiency model. Premium-efficiency motors typically cut losses by 10 to 40 percent (increasing motor efficiency by 1 to 10 points) and carry a cost premium of 15 to 30 percent compared with a standard motor.

In retrofit situations, users also have the choice of repairing failed motors or replacing them. It is becoming common practice among energy-conscious companies to replace all failed, moderate-duty induction motors up to about 125 horsepower (hp) with new premium-efficiency models rather than repairing and rewinding the failed motor. This is because motor rewinds often degrade motor efficiency by 1 to 3 percent.

Go through the different parameters of induction motor to others types of motors like efficiency ,cost ,durable ,performance etc .....

You will get your ans.

With the advent of power electronics devices, it is possible to use ac motors, especially, induction motor in variable speed drives.It has flexible speed control strategy. Speed can be varied within a wide range. It requires less maintenance due to absence commutator and brushes. It has high torque to weight ratio.It doesn't require starting torque. It has rugged construction and can be employed in dirty and radioactive environment.

having good efficiency up to 97% - self-starting - Less maintenance is required because no brushes needs (in case of Squirrel cage IM type) - The construction is simple and robust and it is cheap