b. A three-phase, 400 V, 50 Hz, 6-poles, 960 rpm, star-connected induction motor has the following parameter per phase referred to the stator; R; = 0.4 0, R2 = 0.2 0, X1 = X2 = 1.5 0 and Xm = 30 Q. The motor is controlled by variable frequency control at a constant flux of rated value. Examine the followings; i. motor speed and stator current at half the rated torque and 25 Hz, ii. assuming the speed-torque curve to be straight lines, solve for part (i) for s < Sm,

b. A three-phase, 400 V, 50 Hz, 6-poles, 960 rpm, star-connected induction motor has the following parameter per phase referred to the stator; R; = 0.4 0, R2 = 0.2 0, X1 = X2 = 1.5 0 and Xm = 30 Q. The motor is controlled by variable frequency control at a constant flux of rated value. Examine the followings; i. motor speed and stator current at half the rated torque and 25 Hz, ii. assuming the speed-torque curve to be straight lines, solve for part (i) for s < Sm,

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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