A 3-phase star connected alternator is rated 30 MVA, 13.8 kV and has the following sequencevalues X1 = 0.25 p.u. X2 = 0.35 p.u. and Xo = 0.10 p.u.The neutral of the alternator is solidlygrounded. Determine the sequence components of currents and fault current when double line toground (LLG) occurs on its terminals. Assume that the alternator is unloaded and is operating atrated voltage.o la1 = -j3.052; Ia2 = -j0.677; Iao = -j2.37, If = -j7.11 or 7.11 L-900o la1 = -j1.052; Ia2 = -j0.477; Iao = -j5.37, If = -j3.11 or 3.11 L-900None of theseo la1 = -j5.052; Ia2 = -j0.577; Iao = -j3.37, If = -j9.11 or 9.11 L-900%3D%3D

A 3-ph star connected alternator has, Rating (S)= 30 MVA Line voltage (VL)= 13.8 kV Positive…

A 3-phase star connected alternator is rated 30 MVA, 13.8 kV and has the following sequence values X1 = 0.25 p.u. X2= 0.35 p.u. and Xo = 0.10 p.u.The neutral of the alternator is solidly grounded. Determine the sequence components of currents and fault current when double line to ground (LLG) occurs on its teminals. Assume that the alternator is unloaded and is operating at rated voltage. o la1 = -j3.052; Ia2 = -j0.677; Iao = -j2.37, If = -j7.11 or 7.11 L-900 o la1 = -j1.052; Ia2 = -j0.477; Iao = -j5.37, If = -j3.11 or 3.11 L-900 %3D None of these o Ia1 = -j5.052; Ia2 = -j0.577; Iao = -j3.37, If = -j9.11 or 9.11 L-900 %3D

A 3-phase star connected alternator is rated 30 MVA, 13.8 kV and has the following sequence values X1 = 0.25 p.u. X2= 0.35 p.u. and Xo = 0.10 p.u.The neutral of the alternator is solidly grounded. Determine the sequence components of currents and fault current when double line to ground (LLG) occurs on its teminals. Assume that the alternator is unloaded and is operating at rated voltage. o la1 = -j3.052; Ia2 = -j0.677; Iao = -j2.37, If = -j7.11 or 7.11 L-900 o la1 = -j1.052; Ia2 = -j0.477; Iao = -j5.37, If = -j3.11 or 3.11 L-900 %3D None of these o Ia1 = -j5.052; Ia2 = -j0.577; Iao = -j3.37, If = -j9.11 or 9.11 L-900 %3D

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 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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