A 480-V, 50HZ, Y-connected, 6-pole synchronous generator has a per-phase synchronous reactance of 1.02. It's full load armature current is 60A at 0.8PF lagging. This generator has friction and windage losses of 1.5kW and core losses of 1.0kW at 60HZ at full load. Since armature resistance is being ignored, assume that l?R losses are negligible. The field current has been adjusted so that terminal voltage is 480V at no load. a) What is the speed of rotation of this generator? b) What is the terminal voltage at full load? What if the generator is then loaded with rated current at unity power factor? c) How efficient is this generator when it is operated at rated current at 0.8PF legaling? d) What is the voltage regulation of this generator at 0.8PF leading ?

A 480-V, 50HZ, Y-connected, 6-pole synchronous generator has a per-phase synchronous reactance of 1.02. It's full load armature current is 60A at 0.8PF lagging. This generator has friction and windage losses of 1.5kW and core losses of 1.0kW at 60HZ at full load. Since armature resistance is being ignored, assume that l?R losses are negligible. The field current has been adjusted so that terminal voltage is 480V at no load. a) What is the speed of rotation of this generator? b) What is the terminal voltage at full load? What if the generator is then loaded with rated current at unity power factor? c) How efficient is this generator when it is operated at rated current at 0.8PF legaling? d) What is the voltage regulation of this generator at 0.8PF leading ?

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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