The one-line diagram of an unloaded power system is shown below. Reactances of the two sections of transmission line are shown on the diagram. The generators and transformers are rated as follows: 20 MVA, 13.8 kV, X = 0.20 p.u Generator 1: Generator 2: Generator 3: 30 MVA, 18 kV, X = 0.20 p.u Transformer Ti: Transformer T2: 30 MVA, 20 kV, X = 0.20 p.u 25 MVA, 220Y/13.8A kV, X = 10% Three single-phase units each rated 10 MVA, 127/18 kV, X = 10% HT sides connected in wye Transformer T3: LT sides connected in delta 35 MVA, 220Y/22Y KV, X = 10% j80 Q j100 Q Line 1 Line 2 T₁ T₂ Draw the impedance diagram with all reactances marked in per unit. Choose a base of 50 MVA, 13.8 kV in the circuit of generator 1.

The one-line diagram of an unloaded power system is shown below. Reactances of the two sections of transmission line are shown on the diagram. The generators and transformers are rated as follows: 20 MVA, 13.8 kV, X = 0.20 p.u Generator 1: Generator 2: Generator 3: 30 MVA, 18 kV, X = 0.20 p.u Transformer Ti: Transformer T2: 30 MVA, 20 kV, X = 0.20 p.u 25 MVA, 220Y/13.8A kV, X = 10% Three single-phase units each rated 10 MVA, 127/18 kV, X = 10% HT sides connected in wye Transformer T3: LT sides connected in delta 35 MVA, 220Y/22Y KV, X = 10% j80 Q j100 Q Line 1 Line 2 T₁ T₂ Draw the impedance diagram with all reactances marked in per unit. Choose a base of 50 MVA, 13.8 kV in the circuit of generator 1.

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 3.33P: Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage...

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