Answer / desingurajan

The emf induced in the rotor depends upon the rotor frequency which further depends on relative speed between rotor and synchronous speed of rotating magnetic field. The relative speed at the time of starting or standstill is maximum and hence large emf in induced in rotor conductors or winding due to which very high current flows in rotor which is generally 5 to 7 times of the full load or running current of an indication motor.

Answer / avd

Dear, Back EMF is not present during starting (till rotor
achieves its speed) Hence starting curent will be high. You
can consider motor as a secondary shorted transformer
during starting. Hope it is clear now...

Answer / vinod kumar

At Starting air gap between the stator and rotor was not magtnetised.To magnetise the air medium it draws more magnetising current.

Answer / sundar

The transformer losses depends on the current and voltage so the ratings of transform is kva not in kw

Answer / soosantony

Dears enjoy with this answer
Induction motor we are giving three phase ac power supply to statar windings so magnetic field induced on statar windings this magnetic field cut the rotor winding its single winding with shorted. So emf induced on rotor winding rotor is closed winding so current is produced on rotor winding this current make more magnetic field so there is interaction between both magnetic field.so easy to rotate construction of rotor rotate force of stator magticfield.when rotor rotate there is produce the end is called back emf.there is any position called resistance but it's AC machine so it's called impedance

Answer / alokbahukhandi

this is due to the reason that a huge amount of energy is required to magnetise the motor to overcome the inertia of the system at standstill position. so that a sufficient amount of starting torque id developed.

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