A 3-phase, 1,200 kVA, 2,300 volts alternator is short circuited and open circuited and is operated at rated speed to produce rated current. With the short circuit removed and the same excitation, the voltage between stator terminals is 850 volts. The effective ac resistance between stator terminals is 1.25 ohms. Determine the percent voltage regulation at 0.9 power factor lagging. Draw the single line diagram.

A 3-phase, 1,200 kVA, 2,300 volts alternator is short circuited and open circuited and is operated at rated speed to produce rated current. With the short circuit removed and the same excitation, the voltage between stator terminals is 850 volts. The effective ac resistance between stator terminals is 1.25 ohms. Determine the percent voltage regulation at 0.9 power factor lagging. Draw the single line diagram.

EBK ELECTRICAL WIRING RESIDENTIAL

19th Edition

ISBN:9781337516549

Author:Simmons

Publisher:Simmons

Chapter28: Overcurrent Protection–fuses And Circuit Breakers

Section: Chapter Questions

Problem 10R: Using the method shown in this unit, what is the approximate short-circuit current available at the...

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