A 100-MVA 12.5-kV 0.85-PF-lagging 50-Hz two-pole Y-connected synchronous generator has a per-unit synchronous reactance of 1.1 and a per-unit armature resistance of 0.012. (a) What are its synchronous reactance and armature resistance in ohms? (b) What is the magnitude of the internal generated voltage E, at the rated conditions? What is its torque angle d at these conditions? (c) Ignoring losses in this generator, what torque must be applied to its shaft by the prime mover at full load? SOLUTION The base phase voltage of this generator is V4me =12,500//3 = 7217 V. Therefore, the base impedance of the generator is 3 V hae 3(7217 V)* Z = -=1.56 N base Sue 100,000,000 VA

A 100-MVA 12.5-kV 0.85-PF-lagging 50-Hz two-pole Y-connected synchronous generator has a per-unit synchronous reactance of 1.1 and a per-unit armature resistance of 0.012. (a) What are its synchronous reactance and armature resistance in ohms? (b) What is the magnitude of the internal generated voltage E, at the rated conditions? What is its torque angle d at these conditions? (c) Ignoring losses in this generator, what torque must be applied to its shaft by the prime mover at full load? SOLUTION The base phase voltage of this generator is V4me =12,500//3 = 7217 V. Therefore, the base impedance of the generator is 3 V hae 3(7217 V)* Z = -=1.56 N base Sue 100,000,000 VA

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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