What will happen if the rotor of an induction motor is fed
from a 3 phase supply and the stator short circuited ?

Answer Posted / 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 .

Is This Answer Correct ?    54 Yes 5 No



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