(b) A 480 V, 220 kVA, 0.80 power factor lagging, 40 Hz, two-pole, Y-connected synchronous generator has a synchronous reactance of 1.2 Q and an armature resistance of 0.035 Q. Its friction and windage losses are 22 kW, and its core losses are 10 kW. The field circuit has a DC voltage and maximum Ip of 200 V and 9 A, respectively. The resistance of the field circuit is adjustable from 20 2 to 200 Q. The Open Circuit Characteristic (OCC) of this generator is shown in Figure Q1(b). (i) Explain the field current when the generator is running at no load using OCC in Figure Q1(b). (ii) By referring to Figure Q1(b) the field current of the generator is adjusted to 3A. Determine the terminal voltage of this generator if it is connected to a A connected load with an impedance of 20230° N. (iii) Calculate the efficiency of the generator.

(b) A 480 V, 220 kVA, 0.80 power factor lagging, 40 Hz, two-pole, Y-connected synchronous generator has a synchronous reactance of 1.2 Q and an armature resistance of 0.035 Q. Its friction and windage losses are 22 kW, and its core losses are 10 kW. The field circuit has a DC voltage and maximum Ip of 200 V and 9 A, respectively. The resistance of the field circuit is adjustable from 20 2 to 200 Q. The Open Circuit Characteristic (OCC) of this generator is shown in Figure Q1(b). (i) Explain the field current when the generator is running at no load using OCC in Figure Q1(b). (ii) By referring to Figure Q1(b) the field current of the generator is adjusted to 3A. Determine the terminal voltage of this generator if it is connected to a A connected load with an impedance of 20230° N. (iii) Calculate the efficiency of the generator.

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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