A 3000V, 24-pole, 50HZ, 3-phase, star-connected induction motor has a slip ring rotor of resistance 0.0162 and standstill reactance 0.2652 per phase. Full-load torque is obtained at a speed of 247 r.p.m. Calculate (i) the ratio of maximum to full-load torque (ii) the speed at maximum torque. Neglect stator impedance. Ans[2.61 , 235 r.p.m.]

A 3000V, 24-pole, 50HZ, 3-phase, star-connected induction motor has a slip ring rotor of resistance 0.0162 and standstill reactance 0.2652 per phase. Full-load torque is obtained at a speed of 247 r.p.m. Calculate (i) the ratio of maximum to full-load torque (ii) the speed at maximum torque. Neglect stator impedance. Ans[2.61 , 235 r.p.m.]

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter35: Harmonics 916

Section: Chapter Questions

Problem 3RQ: Would a positive-rotating harmonic or a negative-rotating harmonic be more harmful to an induction...

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