QUESTION 3The following test results are obtained for a 3ph, 25 kV, 750 MVA, 50 Hz, 3600rpm, star-connectedsynchronous machines at rated speed.4, (A)Vu (kV)open-circuit test1, (A)short-circuit testVu (kV)air gap line15002510,00030i. Determine the unsaturated and saturated values of the synchronous reactance in ohms and pu.If a short-circuit test is performed at constant field current 1500 A but at different speeds; 1000, 2000, 3000and 3600 rpm.ii. Determine the short-circuit current at these speeds above.ii. Determine the field current if the synchronous machine delivers rated MVA to an infinite bus at 0.9 laggingpower factor.

An alternator/Synchronous generator is a type of electrical machine that converts mechanical energy…

Answered: QUESTION 3 The following test results…

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter7: Symmetrical Faults

Section: Chapter Questions

Problem 7.8P

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