5. Three single-phase transformers rated at 250 kVA, 7200 V/600 V, 60 Hz, are connected in wye-delta on a 12470 V, 3-phase line. If the load is 450 kVA, calculate the following currents: (1) In the incoming and outgoing transmission lines (2) In the primary and secondary windings (3) If this transformer is used to raise the voltage of a 3-phase, 600 V line to 7.2 kV. (a) How must they be connected? (b) Calculate the line currents for a 600 kVA load. (c) Calculate the corresponding primary and secondary currents.

5. Three single-phase transformers rated at 250 kVA, 7200 V/600 V, 60 Hz, are connected in wye-delta on a 12470 V, 3-phase line. If the load is 450 kVA, calculate the following currents: (1) In the incoming and outgoing transmission lines (2) In the primary and secondary windings (3) If this transformer is used to raise the voltage of a 3-phase, 600 V line to 7.2 kV. (a) How must they be connected? (b) Calculate the line currents for a 600 kVA load. (c) Calculate the corresponding primary and secondary currents.

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 3.33P: Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage...

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In per-unit equivalent circuits of practical three-phase transformers, under balanced thr-phase operation, in which of the following connect ions would a phase-shifting transformer come up? (a) Y-Y (b) Y- (c) -
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