Example 3.5 Three single-phase transformers are connected in A-A to provide power for a three-phase wye- connected 200 kVA load with a 0.80 lagging power factor and an 80 kVA single-phase light load with a 0.90 lagging power factor, as shown in Figure 3.43. TAC I, BO 0.90 PF FIGURE 3.43 For Example 3.5. Application of Distribution Transformers 133 Assume that the three single-phase transformers have equal percent impedance and equal ratios of percent reactance to percent resistance. The primary-side voltage of the bank is 7,620/13,200 V and the secondary-side voltage is 240 V. Assume that the single-phase transformer connected between phases b and c is rated at 100 kVA and the other two are rated at 75 kVA. Determine the following: The line current flowino in each seconda "A*

Example 3.5 Three single-phase transformers are connected in A-A to provide power for a three-phase wye- connected 200 kVA load with a 0.80 lagging power factor and an 80 kVA single-phase light load with a 0.90 lagging power factor, as shown in Figure 3.43. TAC I, BO 0.90 PF FIGURE 3.43 For Example 3.5. Application of Distribution Transformers 133 Assume that the three single-phase transformers have equal percent impedance and equal ratios of percent reactance to percent resistance. The primary-side voltage of the bank is 7,620/13,200 V and the secondary-side voltage is 240 V. Assume that the single-phase transformer connected between phases b and c is rated at 100 kVA and the other two are rated at 75 kVA. Determine the following: The line current flowino in each seconda "A*

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

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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

100%

Example 3.5
Three single-phase transformers are connected in A-A to provide power for a three-phase wye-
connected 200 kVA load with a 0.80 lagging power factor and an 80 kVA single-phase light load
with a 0.90 lagging power factor, as shown in Figure 3.43.
TAC
I,
BO
2.
RO kVA
0.90 PF
Co
FIGURE 3.43 For Example 3.5.
Application of Distribution Transformers
133
Assume that the three single-phase transformers have equal percent impedance and equal ratios
of percent reactance to percent resistance. The primary-side voltage of the bank is 7,620/13,200 V
and the secondary-side voltage is 240 V. Assume that the single-phase transformer connected
between phases b and c is rated at 100 kVA and the other two are rated at 75 kVA. Determine
the following:
a. The line current flowing in each secondary-phase wire
-"A*

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