Problem: A 50-kVA, 13,800/208 V Delta-Wye distribution transformer has a resistance of 1 percent and a reactance of 7 percent per unit. a. What is the ohmic value of transformer’s phase impedance referred to the low voltage side b. Draw the three-phase circuit referred to low voltage side ignoring the excitation branch of the three-phase transformer c. Calculate this transformer’s voltage regulation at full load and 0.8 PF lagging, using the calculated low-side impedance.

Problem: A 50-kVA, 13,800/208 V Delta-Wye distribution transformer has a resistance of 1 percent and a reactance of 7 percent per unit. a. What is the ohmic value of transformer’s phase impedance referred to the low voltage side b. Draw the three-phase circuit referred to low voltage side ignoring the excitation branch of the three-phase transformer c. Calculate this transformer’s voltage regulation at full load and 0.8 PF lagging, using the calculated low-side impedance.

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 3.13P: A single-phase 50-kVA,2400/240-volt,60-Hz distribution transformer has a 1-ohm equivalent leakage...

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Similar questions

The ideal transformer windings are eliminated from the per-unit equivalent circuit of a transformer. (a) True (b) False
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Why is it important to reduce the moisture within a transformer to acceptable levels during transformer installation?