A 100-MVA, 230/115-kV, A-Y three-phase power transformer has a per-unit resis- tance of 0.015 pu and a per-unit reactance of 0.06 pu. The excitation branch elements are Rc 100 pu and XM 20 p = 0 pu. = (a) If this transformer supplies a load of 80 MVA at 0.8 PF lagging, draw the pha- sor diagram of one phase of the transformer. (b) What is the voltage regulation of the transformer bank under these conditions? (c) Sketch the equivalent circuit referred to the low-voltage side of one phase of this transformer. Calculate all the transformer impedances referred to the low- voltage side. (d) Determine the losses in the transformer and the efficiency of the transformer un- der the conditions of part (b).

A 100-MVA, 230/115-kV, A-Y three-phase power transformer has a per-unit resis- tance of 0.015 pu and a per-unit reactance of 0.06 pu. The excitation branch elements are Rc 100 pu and XM 20 p = 0 pu. = (a) If this transformer supplies a load of 80 MVA at 0.8 PF lagging, draw the pha- sor diagram of one phase of the transformer. (b) What is the voltage regulation of the transformer bank under these conditions? (c) Sketch the equivalent circuit referred to the low-voltage side of one phase of this transformer. Calculate all the transformer impedances referred to the low- voltage side. (d) Determine the losses in the transformer and the efficiency of the transformer un- der the conditions of part (b).

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 3.16P: A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters:...

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