9. Four identical alternators each rated for 20 MVA, 11 KV have a subtransient reactance of 164 are working in parallel. The short circuit level at the bus bar is a. 500 MVA b. 125 MVA c. 400 MVA d. 80 MVA A generator having a solidly grounded neutral and arte 10. 50-MVA, 30 kV has positive, negative and zero sequence reactances of 25, 15 and 5 percent respectively. What reactance must be placed in the generator neutral to limit the fault current for a line to ground fault to that for a three phase fault? a. 1.330 b. 1.80 c. 0.80 d. 0.12

9. Four identical alternators each rated for 20 MVA, 11 KV have a subtransient reactance of 164 are working in parallel. The short circuit level at the bus bar is a. 500 MVA b. 125 MVA c. 400 MVA d. 80 MVA A generator having a solidly grounded neutral and arte 10. 50-MVA, 30 kV has positive, negative and zero sequence reactances of 25, 15 and 5 percent respectively. What reactance must be placed in the generator neutral to limit the fault current for a line to ground fault to that for a three phase fault? a. 1.330 b. 1.80 c. 0.80 d. 0.12

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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