Problem 1) A synchronous motor is supplied from a 3 phase, 208V, 60HZ power supply. The field excitation is adjusted so that the power factor is unity when the motor draws 3kW from the supply. The machine has negligible armature resistance and an inductive reactance of 8 ohms. a) Find the field excitation voltage and power angle. Draw the corresponding phasor diagram. b) If the field excitation is held constant and the shaft load is slowly increased, determine the maximum torque (i.e., pull-out torque) that the motor can deliver.

Problem 1) A synchronous motor is supplied from a 3 phase, 208V, 60HZ power supply. The field excitation is adjusted so that the power factor is unity when the motor draws 3kW from the supply. The machine has negligible armature resistance and an inductive reactance of 8 ohms. a) Find the field excitation voltage and power angle. Draw the corresponding phasor diagram. b) If the field excitation is held constant and the shaft load is slowly increased, determine the maximum torque (i.e., pull-out torque) that the motor can deliver.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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