A 3-phase, 50-Hz, 415V, Y-connected, 4-pole, squirrel-cage rotor induction motor, has a per-phase of rotor winding impedance of 0.015+j0.08Ω. Assuming that the stator winding impedance is negligible, determine the following; i) The maximum slip, smax ii) The maximum pull-out torque, τmax iii) The required starting torque, τstart iv) The external resistance that should be added in series with rotor resistance if ratio between starting torque and the maximum torque should be 0.85

A 3-phase, 50-Hz, 415V, Y-connected, 4-pole, squirrel-cage rotor induction motor, has a per-phase of rotor winding impedance of 0.015+j0.08Ω. Assuming that the stator winding impedance is negligible, determine the following; i) The maximum slip, smax ii) The maximum pull-out torque, τmax iii) The required starting torque, τstart iv) The external resistance that should be added in series with rotor resistance if ratio between starting torque and the maximum torque should be 0.85

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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