
Introductory Circuit Analysis (13th Edition)
13th Edition
ISBN: 9780133923605
Author: Robert L. Boylestad
Publisher: PEARSON
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A 100-kVA, 3,000-V, 50-Hz, 3-phase star-connected alternator has effective armature resistance of 0.2 Ω. A field current
of 40 A produces short-circuit current of 200 A and an open-circuit e.m.f. of 1040 V (line value). Calculate the full-load
percentage regulation at a power factor of 0.8 lagging.

Transcribed Image Text:A 3-phase star-connected alternatar is excited
ta give 6600v between lines an open Circuit It has
a vesistance of 0.5w and synchranous veactance
of 5w per phase Galculate the termina valtage and
regulation at fuload current of 130a when the pf.
Is (1) 0.8lagging, (1i) 0.6 leading.
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