The per-unit system calculations method allows to: Select one: O a. improve the efficiency of the power system. O b. eliminate the need for explicit voltage-level conversions at every transformer in the system. O c. reduce the losses in transformers. O d. None of the above

The per-unit system calculations method allows to: Select one: O a. improve the efficiency of the power system. O b. eliminate the need for explicit voltage-level conversions at every transformer in the system. O c. reduce the losses in transformers. O d. None of the above

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 3.13MCQ: Consider the adopted per-unit system for the transformers. Specify true or false for each of the...

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The per-unit system calculations method
allows to:
Select one:
a. improve the efficiency of the power
system.
O b. eliminate the need for explicit
voltage-level conversions at every
transformer in the system.
c. reduce the losses in transformers.
O d. None of the above

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Consider three ideal single-phase transformers (with a voltage gain of ) put together as three-phase bank as shown in Figure 3.35. Assuming positive-sequence voltages for Va,Vb, and Vc find Va,Vb, and VC. in terms of Va,Vb, and Vc, respectively. (a) Would such relationships hold for the line voltages as well? (b) Looking into the current relationships, express IaIb and Ic in terms of IaIb and Ic respectively. (C) Let S and S be the per-phase complex power output and input. respectively. Find S in terms of S.
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