A star-connected 3-phase synchronous motor operates at a frequency of 50 Hz and a line voltage of 380 V and serves a load of 20 kW at a single load factor of 0.8. The field winding has 4 poles. If the synchronous reactance of the motor is 1 Ohm and the armature resistance is neglected determine: a. Difference between synchronous motor and induction motor b. induced voltage in the armature and torque angle of the motor c. motor speed if motor load is reduced to 5 kW

A star-connected 3-phase synchronous motor operates at a frequency of 50 Hz and a line voltage of 380 V and serves a load of 20 kW at a single load factor of 0.8. The field winding has 4 poles. If the synchronous reactance of the motor is 1 Ohm and the armature resistance is neglected determine: a. Difference between synchronous motor and induction motor b. induced voltage in the armature and torque angle of the motor c. motor speed if motor load is reduced to 5 kW

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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