Answer / jaiiseelan

Yes,by increase the frequency of motor by using variable
frequency drive(VFD).

Answer / swapnil patil

An induction motor rotor runs because of the torque created
in the rotor which is directly proportional to the relative
speed between rotor and stator.When motor tries to achieve
the synchronous speed, relative speed becomes zero and so
the torque also becomes zero.So induction motor can never
run at a speed more than or equal to synchronous
speed.Rated speed refers to speed of motor at full
load.Motor can have speed greater than rated speed butnot
beyond synchronous speed.

Answer / padmanabh thakur

wheninduction motor run over synchoronous speed then it
behave as generator.
this can be done by using flux control or by external means

Answer / anil

yes by using flux control method

Answer / sachin_pawaskar2001

Yes. Either by reducing pole or increasing supply frequency.

Answer / b.murali dhara babu

speed of the Induction motor can be caliculated using the
formula N=120*f/p , N = speed of the motor , f= frequncy
of the supply , p = pairs of poles .The speed of the
induction motor is always runs at less than its
synchronous speed due to leakage flux from stator to the
rotor .If change the parameters llike f, p the motor
rated speed also changes again the new speed is less thaqn
it synchronous speed due to the leakage flux and rotor
inertia and friction .

Answer / vishal

yes,
1) By flux control method,but not suitable for plain ind.
motor & old technique
2) you can have two speed motor, but limited speed
variation. again speed will lower than rated.
3) By putting VFD's, but motor deration is required.

Answer / alacoque jean

Yes, by flux control.
Rated speed is the maximum motor speed at full torque (full load).
To increase the motor speed beyong the rated speed, one must decrease the motor flux module, with a constant feeding voltage and a maximum decreasing torque in inverse ratio of the speed.
This can be made with inverter and voltage vector control as "Field Oriented Control".
The feeding frequency increase.

Answer / suresh

no

Answer / padmanabh thakur

rated speed means no load speed .at no load, speed of rotor
is approximately equal to the speed of stator magnenetic
field,so slip become zero and hence torque devlop to rotate
rotor is also equal to zero.

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