Figure 7.4 shows two 11 kV generators feeding a 132 kV double circuit line through gen- erator transformers. Each 132 kV line is 40 km long and with an inductive reactance of 0.40/km. Calculate the fault level for a three-phase fault at: Gen.1 11 kV 125 MVA X = 28% 11/132 kV 125 MVA X = 18% 40km B a. Point A on the busbar close to generator 1. b. Point B at the mid-point of one of the lines. A Gen.2 11 kV 75 MVA X = 18% 132/11 KV 90 MVA X = 12% Use a 100 MVA base for the calculation, express your answer in Amperes and ignore the effect of any system loads.

Figure 7.4 shows two 11 kV generators feeding a 132 kV double circuit line through gen- erator transformers. Each 132 kV line is 40 km long and with an inductive reactance of 0.40/km. Calculate the fault level for a three-phase fault at: Gen.1 11 kV 125 MVA X = 28% 11/132 kV 125 MVA X = 18% 40km B a. Point A on the busbar close to generator 1. b. Point B at the mid-point of one of the lines. A Gen.2 11 kV 75 MVA X = 18% 132/11 KV 90 MVA X = 12% Use a 100 MVA base for the calculation, express your answer in Amperes and ignore the effect of any system loads.

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 7.14P: Equipment ratings for the five-bus power system shown in Figure 7.15 are as follows: Generator G1:Â...

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