A 30 MVA generator with 15% reactance is connected to a bus bar. A 25 MVA transformer with 10% reactance is also connected through a 10% bus bas reactor to the same bus bar. Both of these reactance is based on 25 MVA. If a feeder taken out from the bus bars through a circuit breaker develops a three-phase fault, what should be the appropriate rating of the current breaker?

A 30 MVA generator with 15% reactance is connected to a bus bar. A 25 MVA transformer with 10% reactance is also connected through a 10% bus bas reactor to the same bus bar. Both of these reactance is based on 25 MVA. If a feeder taken out from the bus bars through a circuit breaker develops a three-phase fault, what should be the appropriate rating of the current breaker?

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 3.34P: Three single-phase, two-winding transformers, each rated 450MVA,20kV/288.7kV, with leakage reactance...

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