A 50-kVA 13.8-kV/208-V (rms, line-line) ∆−Ythree-phase distribution transformer has a per-unit resistance of 1 percent and a per-unit reactance of 0.07 pu. Neglect the excitation branchelements, and answer the following questions. (a) What is the transformer’s phase impedance referred to the high-voltage side? Calculate it inΩ. (b) Calculate this transformer’s voltage regulation using the calculated high-side impedance inΩ if it supplies a full load at 0.866 PF lagging. (c) Calculate this transformer’s voltage regulation under the same conditions, using the per-unitsystem.

A 50-kVA 13.8-kV/208-V (rms, line-line) ∆−Ythree-phase distribution transformer has a per-unit resistance of 1 percent and a per-unit reactance of 0.07 pu. Neglect the excitation branchelements, and answer the following questions. (a) What is the transformer’s phase impedance referred to the high-voltage side? Calculate it inΩ. (b) Calculate this transformer’s voltage regulation using the calculated high-side impedance inΩ if it supplies a full load at 0.866 PF lagging. (c) Calculate this transformer’s voltage regulation under the same conditions, using the per-unitsystem.

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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