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is this correct (2 Viewers)

Arithela

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The operation of AC motors
-[FONT=&quot] [/FONT]A 3-phase AC current, which are 120 degrees out of phase with each other, is passed through the 3 pairs of electromagnets on the stator, and this produces a rotating magnetic field.
-[FONT=&quot] [/FONT]As a result, the rotor experiences a change in flux, and induces a current (Faraday’s Law).
-[FONT=&quot] [/FONT]The induced current generates a magnetic field that opposes the original change in flux (Lenz’s Law).
-[FONT=&quot] [/FONT]As a result, the induced eddy currents generate a magnetic field that opposes the magnetic field produced by the rotating magnetic fields of the stator.
-[FONT=&quot] [/FONT]This causes the rotor to be “dragged” along with the rotating magnetic field caused by the stator, hence causing it to rotate in the same direction as the moving magnetic field.


i dont get how the rotor gets dragged along with the rotating magnetic field DUE to the induced eddy currents generating a magneic field that opposes the original magnetic field produced by the stator
 

wogblogger

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Arithela said:
i dont get how the rotor gets dragged along with the rotating magnetic field DUE to the induced eddy currents generating a magneic field that opposes the original magnetic field produced by the stator
well i like to think its the "chaser", the rotating magnetic feild is rotating(lol), this causes a change in field passing through the conductor,,, and as we know things dont like to change to much (kinda lik le chatelier), and so to minimise the change in flux the induced eddy currents will spin in such a way to reduce the amount of change.

and so we have a rotating magnetic field that is being "chased" by the induced eddy currents

you might want to read about slipage i think thats how u spell it. its basically then the "chaser" falls to far behind and somthing needs to be done.

just remember that nothing likes to change and so everything is relative to somthing else
 

me121

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Arithela said:
The operation of AC motors
-[FONT=&quot] [/FONT]A 3-phase AC current, which are 120 degrees out of phase with each other, is passed through the 3 pairs of electromagnets on the stator, and this produces a rotating magnetic field.r
it does not HAVE to be 3-phase. some ac motors are, some are not.
 

a-n-d-r-e-w

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Arithela said:
i dont get how the rotor gets dragged along with the rotating magnetic field DUE to the induced eddy currents generating a magneic field that opposes the original magnetic field produced by the stator
the rotating magnetic field creates a constantly changing magnetic flux that threads the bars of the squirrel cage of an ac induction motor. This constantly changing magnetic flux induces a current such that it opposes the change that caused it (Lenz's Law), current carrying conductors in magnetic fields experience a force, this force pushes the cage such that it 'chases' the rotating magnetic field.

I hope ive answered what your asking, it should help
 

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