A 3Ø, Y-connected alternator is rated at 1,600KVA, 13.5KV. The armature effective AC resistance per phase is 1.52. The percentage regulation for a load of 1,280kW at unity power factor is 3.5%. Determine: (a) synchronous reactance of the alternator (b) %VR at full-load 0.8pf leading (c) What is the effect on %VR value if taken at half-load lagging pf? Justify and explain briefly your answer on one(1) sentence.

A 3Ø, Y-connected alternator is rated at 1,600KVA, 13.5KV. The armature effective AC resistance per phase is 1.52. The percentage regulation for a load of 1,280kW at unity power factor is 3.5%. Determine: (a) synchronous reactance of the alternator (b) %VR at full-load 0.8pf leading (c) What is the effect on %VR value if taken at half-load lagging pf? Justify and explain briefly your answer on one(1) sentence.

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

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.46P: The motors M1andM2 of Problem 3.45 have inputs of 120 and 60 MW, respectively, at 13.2 kV, and both...

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