A 3Ø, 2000KW, 480V A-connected alternator is short-circuited and is operated at rated speed to produce rated current at 4A excitation. With the short-circuit remove and with the excitation adjusted to 5A, the voltage between stator terminal is 330V. The effective resistance between terminal as measured with dc is 20. Determine the %V.R. of the alternator at half-load and pf of 0.8 leading without changing any given values.

A 3Ø, 2000KW, 480V A-connected alternator is short-circuited and is operated at rated speed to produce rated current at 4A excitation. With the short-circuit remove and with the excitation adjusted to 5A, the voltage between stator terminal is 330V. The effective resistance between terminal as measured with dc is 20. Determine the %V.R. of the alternator at half-load and pf of 0.8 leading without changing any given values.

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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