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

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.1P

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