A 400 V, 4 Pole, 3-phase, 50 Hz star conp d inducion motor has a rotor resistance andreactance per phase equal to 0.012/Phase and 0.10/mhase respectively. The magnitude of the inducede.m.f. in the rotor at standstill condition is 57 725V/Phase The full-load speed is 1440 r.p.m.Determine: i) The starting torque. ii) The addifional rotor resistance required to produce 577 of themaximum torque at starting. iii) The frequency of rotor current at full-load.

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A 400 V, 4 Pole, 3-phase, 50 Hz star connected induction motor has a rotor resistance and reactance per phase equal to 0.0132/Phase and 0.10mbese resnectively. The magnitude of the induced e.m.f. in the rotor at standstill condition is 57 725/Phase The full-load speed is 1440 r.p.m. Determine: i) The starting torque. ii) The additional rotor resistance required to produce 577 of the maximum torque at starting. iii) The frequenc rent at full-load

A 400 V, 4 Pole, 3-phase, 50 Hz star connected induction motor has a rotor resistance and reactance per phase equal to 0.0132/Phase and 0.10mbese resnectively. The magnitude of the induced e.m.f. in the rotor at standstill condition is 57 725/Phase The full-load speed is 1440 r.p.m. Determine: i) The starting torque. ii) The additional rotor resistance required to produce 577 of the maximum torque at starting. iii) The frequenc rent at full-load

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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