b) The motor is supposed to carry a conveyer where requires a minimum and maximum mechanical torques of 30 and 50 N.m, respectively. The efficiency of the motor at its full-load condition is calculated to be 90.78%. We are interested to increase the efficiency of the motor without losing much on the mechanical torque. An electrical engineer proposed that if we increase the rotor resistance or rotor reactance, the efficiency of the motor would be increased. As a student in electrical machine class, recommend which of the following approach would be more suitable for this conveyer application and justify your answer? i. By doubling the per-phase rotor winding leakage reactance. ii. By doubling the per-phase rotor winding resistance.

b) The motor is supposed to carry a conveyer where requires a minimum and maximum mechanical torques of 30 and 50 N.m, respectively. The efficiency of the motor at its full-load condition is calculated to be 90.78%. We are interested to increase the efficiency of the motor without losing much on the mechanical torque. An electrical engineer proposed that if we increase the rotor resistance or rotor reactance, the efficiency of the motor would be increased. As a student in electrical machine class, recommend which of the following approach would be more suitable for this conveyer application and justify your answer? i. By doubling the per-phase rotor winding leakage reactance. ii. By doubling the per-phase rotor winding resistance.

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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