(a) Draw (neatly) a phasor diagram showing the three, primary line-to-line voltages and the six secondary phase and line voltages. What is the phase relationship between the primary voltage VAn and the secondary voltage V12? Indicate on the phasor diagram. (b) Determine the apparent power rating of each single-phase transformer required for this application. (c) Determine the nameplate voltage ratings of cach single-phase transformer required for this application. (d) Determine the primary (HV) coil and line currents (magnitudes only) when the 3-ph transformer bank is delivering 120 kVA at 575 Vu.

(a) Draw (neatly) a phasor diagram showing the three, primary line-to-line voltages and the six secondary phase and line voltages. What is the phase relationship between the primary voltage VAn and the secondary voltage V12? Indicate on the phasor diagram. (b) Determine the apparent power rating of each single-phase transformer required for this application. (c) Determine the nameplate voltage ratings of cach single-phase transformer required for this application. (d) Determine the primary (HV) coil and line currents (magnitudes only) when the 3-ph transformer bank is delivering 120 kVA at 575 Vu.

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 3.26P: A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a...

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