Example 37.30. A 3.5-MVA, Y-connected alternator rated at 4160 volts at 50-Hz has the open-circuit characteristic given by the following data:Field Current (Amps)50100150200250300350400450E.M.F. (Volts)162031504160475051305370555056505750A field current of 200 A is found necessary to circulate full-load current on short-circuit of thealternator. Calculate by (i) synchronous impedance method and (ii) ampere-turn method the full-load voltage regulation at 0.8 p.f. lagging. Neglect resistance. Comment on the results obtained.1.A 30-kVA, 440-V, 50-Hz, 3-0, star-connected synchronous generator gave the following test data :Field current (A)46.101214Terminal volts:155287395440475530570592S.C. current1122344046576980:Resistance between any two terminals is 0.3 2Find regulation at full-load 0.8 p.f. lagging by (a) synchronous impedance method and (b) Rothert'sampere-turn method. Take Z, corresponding to S.C. current of 80 A.[(a) 51% (b) 29.9%]

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1. A 30-kVA, 440-V, 50-Hz, 3-0, star-connected synchronous generator gave the following test data: Field current (A) 4. 6. 7 10 12 14 Terminal volts 155 287 395 440 475 530 570 592 S.C. current 11 22 34 40 46 57 69 80 Resistance between any two terminals is 0.3 2 Find regulation at full-load 0.8 p.f. lagging by (a) synchronous impedance method and (b) Rothert's ampere-turn method. Take Z, corresponding to S.C. current of 80 A. [(a) 51% (b) 29.9%]

1. A 30-kVA, 440-V, 50-Hz, 3-0, star-connected synchronous generator gave the following test data: Field current (A) 4. 6. 7 10 12 14 Terminal volts 155 287 395 440 475 530 570 592 S.C. current 11 22 34 40 46 57 69 80 Resistance between any two terminals is 0.3 2 Find regulation at full-load 0.8 p.f. lagging by (a) synchronous impedance method and (b) Rothert's ampere-turn method. Take Z, corresponding to S.C. current of 80 A. [(a) 51% (b) 29.9%]

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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