Q1: The following test results are obtained on a 7,500-line V alternator: O.C.V.: 3,100 4,900 6,600 7,500 8,300 Field current (A): 16 25 37.5 50 70 A field current of 20 A is found necessary to circulate full-load current on short-circuit of the armature. Calculate by (i) the ampere-turn method and (ii) the synchronous impedance method the full-load regulation at 0.8 p.f. (lag). Armature resistance is 2 ohm and leakage reactance is 2 ohm.

Q1: The following test results are obtained on a 7,500-line V alternator: O.C.V.: 3,100 4,900 6,600 7,500 8,300 Field current (A): 16 25 37.5 50 70 A field current of 20 A is found necessary to circulate full-load current on short-circuit of the armature. Calculate by (i) the ampere-turn method and (ii) the synchronous impedance method the full-load regulation at 0.8 p.f. (lag). Armature resistance is 2 ohm and leakage reactance is 2 ohm.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter31: Three-phase Alternators

Section: Chapter Questions

Problem 1RQ: What conditions must be met before two alternators can be paralleled together?

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