Three single-phase distribution transformers, each rated for 18kVA, 20000/220 volts, are connected in a Dy three-phase bank.For convenience, at the factory, the OCT and the SCT were per-formed as per standards with the whole three-phase bank alreadyconnected and the measured values were as follows:Vline 381.051V, line 1.78436A, P30 = 372.414 W.Vline = 5656.85 V, Iline = 1.55885 A, P30 = 2160 W.Three phase bank of single phase transformer on a utility pole.37.5 K(a) Find the single phase equivalent circuit referred to the low volt-age side.(b) Find the transformer regulation at the rated load and voltageand a power factor of 0.45 lagging (Neglect the excitation current).(c) Using the "load" model, what is the approximate transformer-bank's efficiency, n, under these conditions of load?(a) R2 X=2Rsc=mXsc = mS(b) Vreg=(c) n = %

Three single-phase distribution transformers are connected in a Dy three-phase bank. Rated power…

Three single-phase distribution transformers, each rated for 18 kVA, 20000/220 volts, are connected in a Dy three-phase bank. For convenience, at the factory, the OCT and the SCT were per- formed as per standards with the whole three-phase bank already connected and the measured values were as follows: Vline 381.051V, line = 1.78436A, P30 = 372.414 W. Vline = 5656.85 V, pline = 1.55885 A, P3 =2160 W. Three phase bank of single phase transformer on a utility pole. 37.5 K (a) Find the single phase equivalent circuit referred to the low volt- age side. (b) Find the transformer regulation at the rated load and voltage and a power factor of 0.45 lagging (Neglect the excitation current). (c) Using the "load" model, what is the approximate transformer- bank's efficiency, n, under these conditions of load?

Three single-phase distribution transformers, each rated for 18 kVA, 20000/220 volts, are connected in a Dy three-phase bank. For convenience, at the factory, the OCT and the SCT were per- formed as per standards with the whole three-phase bank already connected and the measured values were as follows: Vline 381.051V, line = 1.78436A, P30 = 372.414 W. Vline = 5656.85 V, pline = 1.55885 A, P3 =2160 W. Three phase bank of single phase transformer on a utility pole. 37.5 K (a) Find the single phase equivalent circuit referred to the low volt- age side. (b) Find the transformer regulation at the rated load and voltage and a power factor of 0.45 lagging (Neglect the excitation current). (c) Using the "load" model, what is the approximate transformer- bank's efficiency, n, under these conditions of load?

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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Concept explainers

Single Phase Transformer

A single-phase transformer is a type of power transformer. It is an electrical device that accepts converts the single phase alternating power into single phase alternating power. In this power conversion the voltage is stepped up or down. If the voltage is stepped up, the current will be stepped down and if the voltage is stepped down, the current will be stepped up.

Question

Three single-phase distribution transformers, each rated for 18
kVA, 20000/220 volts, are connected in a Dy three-phase bank.
For convenience, at the factory, the OCT and the SCT were per-
formed as per standards with the whole three-phase bank already
connected and the measured values were as follows:
Vline 381.051V, line 1.78436A, P30 = 372.414 W.
Vline = 5656.85 V, Iline = 1.55885 A, P30 = 2160 W.
Three phase bank of single phase transformer on a utility pole.
37.5 K
(a) Find the single phase equivalent circuit referred to the low volt-
age side.
(b) Find the transformer regulation at the rated load and voltage
and a power factor of 0.45 lagging (Neglect the excitation current).
(c) Using the "load" model, what is the approximate transformer-
bank's efficiency, n, under these conditions of load?
(a) R2 X=2
Rsc=mXsc = mS
(b) Vreg=
(c) n = %

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