Question Two A generating station consisting of two generators, one of 20 MVA, 11 kV, 0.18 pu reactance with the unit transformer of 20 MVA, 11/132 kV, 0.08 pu reactance, another of 30 MVA, 11 kV, 0.18 pu reactance with the transformer of 30 MVA, 11/132 kV, 0.12 pu reactance, transmits power over double circuit 132-kV transmission line. Each line is having reactance of 120 ohms per phase. Determine the fault current supplied by the generators to a three-phase solid fault on the 132-kV bus-bar at the receiving end. Neglect pre-fault current and losses. Assume pre-fault generated voltages at rated value.

Question Two A generating station consisting of two generators, one of 20 MVA, 11 kV, 0.18 pu reactance with the unit transformer of 20 MVA, 11/132 kV, 0.08 pu reactance, another of 30 MVA, 11 kV, 0.18 pu reactance with the transformer of 30 MVA, 11/132 kV, 0.12 pu reactance, transmits power over double circuit 132-kV transmission line. Each line is having reactance of 120 ohms per phase. Determine the fault current supplied by the generators to a three-phase solid fault on the 132-kV bus-bar at the receiving end. Neglect pre-fault current and losses. Assume pre-fault generated voltages at rated value.

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 3.21MCQ: In order to avoid difficulties with third-harmonic exciting current, which three-phase transformer...

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