Assignment • Given the one-line diagram of an unloaded power system, Draw the reactance diagram with all reactances in per unit. Choose a base of 30MVA, 6.9 kV in the circuit of gen 1. 100-10 MY 442 100 800 000 • • • • Generator 1: 20 MVA, 6.9 kV, X" = 0.15 pu Generator 3: 30 MVA, 13.8 kV, X" = 0.15 pu Generator 2: 10 MVA, 6.9 kV, X" = 0.15 pu Transformer T1: 25 MVA, 6.9A/115Y KV, X = 10% Transformer T2: 12 MVA, 6.9A/115Y kV, X = 10% Transformer T3: 3-single-phase units each rater 10MVA, 7.5/75 kV, X = 10%

Assignment • Given the one-line diagram of an unloaded power system, Draw the reactance diagram with all reactances in per unit. Choose a base of 30MVA, 6.9 kV in the circuit of gen 1. 100-10 MY 442 100 800 000 • • • • Generator 1: 20 MVA, 6.9 kV, X" = 0.15 pu Generator 3: 30 MVA, 13.8 kV, X" = 0.15 pu Generator 2: 10 MVA, 6.9 kV, X" = 0.15 pu Transformer T1: 25 MVA, 6.9A/115Y KV, X = 10% Transformer T2: 12 MVA, 6.9A/115Y kV, X = 10% Transformer T3: 3-single-phase units each rater 10MVA, 7.5/75 kV, X = 10%

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 3.32P: Determine the positive- and negative-sequence phase shifts for the three- phase transformers shown...

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