The full load speed of a three-phase four-pole 50Hz, 160kW induction motor is 1,475rpm. The starting...

The full load speed of a three-phase four-pole 50Hz, 160kW induction motor is 1,475rpm.
The starting torque is 170%, the yield torque is 280% of the rated torque,
and the moment of inertia of the rotor is 2.5kg-m ^ 2.
The torque of the load converted to the motor shaft is 800 N-m at full load speed
and the moment of inertia is 20 kg-m ^ 2.

a) Find the starting time when the load torque is assumed to be constant.
b) Find the start time assuming load torque is proportional to speed.
c) Find the starting time assuming load torque is proportional to the square of the speed.
d) Find the starting time when the load torque is assumed to be pure inertia with zero.

answer -
a) 2.7sec
b) 2.0sec
c) 1.9sec
d) 1.7sec

Expert Solution

Manojponduru answered 7 months ago

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