QUESTION FOUR A single-phase 1kVA, 440/110V, 50 Hz transformer has the following equivalent circuit parameters. R1=4.992; R2=0.302; X1=5.502; X2=0.3502; Rel=645002; Xml = 35000; (a) Calculate the equivalent winding resistance and the equivalent leakage reactance of this transformer referred to the high-voltage side and draw the approximate equivalent circuit (referred to the high-voltage side). (b) Calculate the full-load copper losses. (c) Calculate the core losses.

QUESTION FOUR A single-phase 1kVA, 440/110V, 50 Hz transformer has the following equivalent circuit parameters. R1=4.992; R2=0.302; X1=5.502; X2=0.3502; Rel=645002; Xml = 35000; (a) Calculate the equivalent winding resistance and the equivalent leakage reactance of this transformer referred to the high-voltage side and draw the approximate equivalent circuit (referred to the high-voltage side). (b) Calculate the full-load copper losses. (c) Calculate the core losses.

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 3.16P: A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters:...

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A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when operated at rated load, 0.8 power factor lagging. This transformer is to be utilized as a 1440/1200-V step-down autotransformer in a power distribution system. (a) Find the permissible kVA rating of the autotransformer if the winding currents and voltages are not to exceed the ratings as a two-winding transformer. Assume an ideal transformer. (b) Determine the efficiency of the autotransformer with the kVA loading of part (a) and 0.8 power factor leading.
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