Answer / rakesh

Now the corrrect answer would be that the rotor will start
rotating in direction opposite to the rotating magnetic
field . say fr ex, the 3 phs supply on the rotor produces a
rotor mmf rotating in clockwise direction then this rotor
flux will cause an induced emf on the stator windings
lagging it by 90* say for a unity pf wrt to e the armature
mmf is also 90* lagging again rotating in clockwise
direction. to oppose this induced emf the stator tries to
rotate in the direction of rotating magnetic field but beng
fixed it fails to do so , in return the rotor in order to
nullify the cause of induced emf starts rotating in
opposite direction to rotating manetic field .

Answer / manas ghosh

It is
just like using the secondary of a transformer as primary. In this case the effective load depending on the value of rotational speed, which is r(1/s - 1) will be on the stator side. so, here 'r' is the actual stator resistance. Here supply side(rotor) acts as primary and stator acts as secondary. All other quantities like silp,Ns remain same but the definition of silp is not the same as in the case of stator side supply.

Answer / vinova

The rotor will run in the opposite direction of rotating
magnatic field of rotor because the induced current in the
stator set up stator rotating magnatic feld now due to
intraction of these two magnatic fields the rotor start
rotating in the opposite direction of rotor magnatic field
so that frequency of stator current become sf (slip* rotor
fed frequency)the interesting point here is that speed of
rotation of stator magnatic field will be very low (rotor
magnatic field- rotor speed). and the resultant magnatic
field will also rotate at very low speed in the space as
copaired to it happen when the stator is fed electrical
supply and rotor is short circuited

Answer / k.prakashchandra

If the rotor winding can sustain the applied voltage ,the
motor runs normally as a squirrel cage motor with less
efficiency.The direction depends on the phase sequence.It is
just like using the secondary of transformer as primary

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