A 100 kVA, 1100 V, three-phase, 6-pole, Y-connected, 50 Hz synchronous machine has synchronous reactance of 6 2 per-phase and negligible armature resistance. Its core losses are 7 kW 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 generator is supplying a line current of 52.5 A at 0.85 PF lagging. Draw the phasor diagram and find the generator efficiency and voltage regulation. Also find the applied torque.

A 100 kVA, 1100 V, three-phase, 6-pole, Y-connected, 50 Hz synchronous machine has synchronous reactance of 6 2 per-phase and negligible armature resistance. Its core losses are 7 kW 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 generator is supplying a line current of 52.5 A at 0.85 PF lagging. Draw the phasor diagram and find the generator efficiency and voltage regulation. Also find the applied torque.

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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