Given a conventional single-phase transformer is converted to a step-up autotransformer asshown in Figure 1.a) If three single phase autotransformers of this kind are connected in Y - Y connection, as tohandle 2000KVA from a 12.6kV distribution line to a 13.8kV distribution line, calculate theapparent power that must the windings of each autotransformer can handle.b) Compare the apparent power calculated in (b) with the per phase apparent power. Are theyequal? If not, where the rest of power goes? Justify your answer by showing the how the restof power being calculated.c) Now if one of the autotransformers was to reconnected as an conventional transformer,calculate its voltages, currents and apparent power ratings. VseV,N,N,(=N,e)Vc( =NJConventional transformerStep up autotransformerFigure 1 Conversion of a conventional transformer to a step-up autotransformerNote:1 = primary currentz = secondary currentV, = primary voltageV2 = secondary voltageVc = primary coil voltageVee = secondary coil voltageIc = primary coil currentIse = secondary coil currentNc = primary coil turnsNge = secondary coil turnsNp = primary total turnsNg = secondary total turns

Solution- a) Since 3 phase, 200 KVA so single phase or apparent power of each windings,…

iven a conventional single-phase transformer is converted to a step-up autotransformer as shown in Figure 1. a) If three single phase autotransformers of this kind are connected in Y Y connection, as to handle 2000k VA from a 12.6kV distribution line to a 13.8kV distribution line, calculate the apparent power that must the windings of each autotransformer can handle. b) Compare the apparent power calculated in (b) with the per phase apparent power. Are they equal? If not, where the rest of power goes? Justify your answer by showing the how the rest of power being calculated.

iven a conventional single-phase transformer is converted to a step-up autotransformer as shown in Figure 1. a) If three single phase autotransformers of this kind are connected in Y Y connection, as to handle 2000k VA from a 12.6kV distribution line to a 13.8kV distribution line, calculate the apparent power that must the windings of each autotransformer can handle. b) Compare the apparent power calculated in (b) with the per phase apparent power. Are they equal? If not, where the rest of power goes? Justify your answer by showing the how the rest of power being calculated.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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