A 15 KVA, 2400: 240/120 V, 60 Hz, the two-winding transformer is to be reconnected as a 2400:2520 V step-up transformer. From test work on the two-winding transformer, it is known that its rated voltage core losses and coil losses are 280 and 300 W, respectively. For this autotransformer, (a) determine the apparent power rating and (b) the full-load efficiency if supplying 2520 V to a 0.8 PF lagging load.

A 15 KVA, 2400: 240/120 V, 60 Hz, the two-winding transformer is to be reconnected as a 2400:2520 V step-up transformer. From test work on the two-winding transformer, it is known that its rated voltage core losses and coil losses are 280 and 300 W, respectively. For this autotransformer, (a) determine the apparent power rating and (b) the full-load efficiency if supplying 2520 V to a 0.8 PF lagging load.

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 3.29MCQ: For developing per-unit equivalent circuits of single-phase three-winding transformer, a common...

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For developing per-unit equivalent circuits of single-phase three-winding transformer, a common Sbase is selected for all three windings and voltage bases are selected in proportion to the rated voltage of the windings (a) True (b) False
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Consider a bank of this single-phase two-winding transformers whose high-voltage terminals are connected to a three-phase, 13.8-kV feeder. The low-voltage terminals are connected to a three-phase substation load rated 2.0 MVA and 2.5 kV. Determine the required voltage, current, and MVA ratings of both windings of each transformer, when the high-voltage/low- voltage windings are connected (a) Y-, (b) -Y, (c) Y-Y, and (d) -.
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Two transformers A and B have the following data Transformer A: 6600/440 V, (250 KVA ) requires ( 6%) of rated voltage to circulate (90%) of full load current at power factor (0.25) when the low voltage winding is short circuited and the no load loss is equal to (2500 W). Transformer B: 6600/420 V, (600 KVA) requires (9%) of rated voltage to circulate (80%) of full load current at power factor (0.16) when low voltage winding is short circuited and no load loss is equal to (4500 W). Calculate the followings: If both transformers are connected in parallel to supply a load (1.2 + j 2.3) ohm, find the output power of each transformer.