1- A 500-kVA, 3-phase, 50 Hz transformer has a voltage ratio (line voltages) of 66/33 kV and is delta/star connected. The resistances per phase are: high voltage 35 2, low voltage 0.876 2 and the iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of full-load respectively (a) at unity pf and (b) 0.8 pf.

1- A 500-kVA, 3-phase, 50 Hz transformer has a voltage ratio (line voltages) of 66/33 kV and is delta/star connected. The resistances per phase are: high voltage 35 2, low voltage 0.876 2 and the iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of full-load respectively (a) at unity pf and (b) 0.8 pf.

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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