Q12:A 100|k VA, 1100 V, three-phase, 6-pole, Y-connected, 50 Hz synchronous machine has synchronous reactance of 6 Q per-phase and negligible armature resistance. Its core losses are 7 k W and its friction and windage losses are 8 kW. The speed droop is 2.5%. initially the machine is operated alone as a generator and the field current is adjusted such that the no-load voltage equals the rated voltage. a) If the prime mover of the machine is removed while the machine is connected to the infinite bus, and field flux of the machine is increased by 11%. Find the power factor for the machine in this case.

Q12:A 100|k VA, 1100 V, three-phase, 6-pole, Y-connected, 50 Hz synchronous machine has synchronous reactance of 6 Q per-phase and negligible armature resistance. Its core losses are 7 k W and its friction and windage losses are 8 kW. The speed droop is 2.5%. initially the machine is operated alone as a generator and the field current is adjusted such that the no-load voltage equals the rated voltage. a) If the prime mover of the machine is removed while the machine is connected to the infinite bus, and field flux of the machine is increased by 11%. Find the power factor for the machine in this case.

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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