Answer or step for A-F A 250 MVA, 25 kV, 3 phase synchronous generator has a synchronous reactanceXs of 1.6 pu. It is delivering the rated output of 250 MVA, 25 kV at the generatorterminals at a power factor of 1.0.(a) Calculate the per unit base impedance of the generator ZB and the synchronousreactance X, in Ohm.(b) Calculate the phase current magnitude.(c) Calculate the per phase voltage drop E – V across the synchronous reactance.(d) Calculate the line to neutral no load voltage E(e) Now suppose there is a 3 phase fault near the generator terminals. Assumingthe field current and E remain the same, calculate the steady state fault currentmagnitude.(f) The initial fault current due to the 3 phase fault is much larger because for tran-sient situations the effective synchronous reactance is much smaller. The transientsynchronous reactance is X = 0.23 pu. Use the transient synchronous reactanceto calculate the initial fault current. This fault current is used to design the circuitbreakers because this is the worst case current that the circuit breakers will have tointerrupt.

According to company policy, i am solve only first 3 part. We can draw the given power system as a)…

A 250 MVA, 25 kV, 3 phase synchronous generator has a synchronous reactance X, of 1.6 pu. It is delivering the rated output of 250 MVA, 25 kV at the generator terminals at a power factor of 1.0. (a) Calculate the per unit base impedance of the generator ZB and the synchronous reactance X, in Ohm. (b) Calculate the phase current magnitude. (c) Calculate the per phase voltage drop E – V across the synchronous reactance.

A 250 MVA, 25 kV, 3 phase synchronous generator has a synchronous reactance X, of 1.6 pu. It is delivering the rated output of 250 MVA, 25 kV at the generator terminals at a power factor of 1.0. (a) Calculate the per unit base impedance of the generator ZB and the synchronous reactance X, in Ohm. (b) Calculate the phase current magnitude. (c) Calculate the per phase voltage drop E – V across the synchronous reactance.

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 7.6P

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