Three single-phase two-winding transformers, each rated (3 mathrm{kVA}, 220 / 110) volts, (60 mathrm{~Hz}), with a 0.10
Question:
Three single-phase two-winding transformers, each rated \(3 \mathrm{kVA}, 220 / 110\) volts, \(60 \mathrm{~Hz}\), with a 0.10 per-unit leakage reactance, are connected as a three-phase extended \(\Delta\) autotransformer bank, as shown in Figure 3.36 (c). The low-voltage \(\Delta\) winding has a 110 volt rating.
(a) Draw the positivesequence phasor diagram and show that the high-voltage winding has a 479.5 volt rating.
(b) A three-phase load connected to the low-voltage terminals absorbs \(6 \mathrm{~kW}\) at 110 volts and at 0.8 power factor lagging. Draw the per-unit impedance diagram and calculate the voltage and current at the high-voltage terminals. Assume positive-sequence operation.
Figure 3.36 (c)
Step by Step Answer:
Power System Analysis And Design
ISBN: 9781305632134
6th Edition
Authors: J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma