A 480-V, 50-Hz, Y -connected, six-pole synchronous generator has a per-phase synchronous reactance of 1.0 n. Its full-load armature current is 60 A at 0.8 PF lagging. This generator has friction and windage losses of 1.5 kW and core losses of 1.0 kW at 60 Hz at full load. Since the armature resistance is being ignored, assume that the 12R losses are negligible. The field current has been adjusted so that the terminal voltage is 480 V at no load. (a) What is the speed of rotation of this generator? (b) What is the terminal voltage of this generator if the following are true? 1. It is loaded with the rated current at 0.8 PF lagging. 2, It is loaded with the rated current at 1.0 PF. 3, It is loaded with the rated current at 0.8 PF leading. (c) What is the efficiency of this generator (ignoring the IUlknown electrical losses) when it is operating at the rated current and 0.8 PF lagging? (d) How much shaft torque must be applied by the prime mover at full load? How large is the induced countertorque? (e) What is the voltage regulation of this generator at 0.8 PF lagging? At 1.0 PF? At 0.8 PF leading?

A 480-V, 50-Hz, Y -connected, six-pole synchronous generator has a per-phase synchronous reactance of 1.0 n. Its full-load armature current is 60 A at 0.8 PF lagging. This generator has friction and windage losses of 1.5 kW and core losses of 1.0 kW at 60 Hz at full load. Since the armature resistance is being ignored, assume that the 12R losses are negligible. The field current has been adjusted so that the terminal voltage is 480 V at no load. (a) What is the speed of rotation of this generator? (b) What is the terminal voltage of this generator if the following are true? 1. It is loaded with the rated current at 0.8 PF lagging. 2, It is loaded with the rated current at 1.0 PF. 3, It is loaded with the rated current at 0.8 PF leading. (c) What is the efficiency of this generator (ignoring the IUlknown electrical losses) when it is operating at the rated current and 0.8 PF lagging? (d) How much shaft torque must be applied by the prime mover at full load? How large is the induced countertorque? (e) What is the voltage regulation of this generator at 0.8 PF lagging? At 1.0 PF? At 0.8 PF 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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