A 50 MVA 230/115-kV, A-Y three-phase connected power transformer has a per unit resistance of 0.015 pu and a per-unit reactance of 0.006 pu. The excitation branch elements are Rc = 125 pu and XM = 20 pu. What is the equivalent branch resistance, Rc, in k2 referred to the low-voltage side?

A 50 MVA 230/115-kV, A-Y three-phase connected power transformer has a per unit resistance of 0.015 pu and a per-unit reactance of 0.006 pu. The excitation branch elements are Rc = 125 pu and XM = 20 pu. What is the equivalent branch resistance, Rc, in k2 referred to the low-voltage side?

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 3.10P: A single-phase step-down transformer is rated 13MVA,66kV/11.5kV. With the 11.5 kV winding...

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Concept explainers

Single Phase Transformer

A single-phase transformer is a type of power transformer. It is an electrical device that accepts converts the single phase alternating power into single phase alternating power. In this power conversion the voltage is stepped up or down. If the voltage is stepped up, the current will be stepped down and if the voltage is stepped down, the current will be stepped up.

Question

A 50 MVA 230/115-kV, A-Y three-phase connected power transformer has a per unit resistance of
0.015 pu and a per-unit reactance of 0.006 pu. The excitation branch elements are Rc = 125 pu and
XM = 20 pu.
What is the equivalent branch resistance, Rc, in kn referred to the low-voltage side?

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