30. A single phase transformer has percentage regulations of 4 and 4.4 for lagging power factors of 0.8 and 0.6, respectively. The full-load copper loss is equal to the iron loss. Calculate (a) the lagging power factor at which the full-load regulation is maximum, and (b) the full-load efficiency at unity power factor. [Ans. : (a) 0.4472 lagging; (b) 96.15 %]

30. A single phase transformer has percentage regulations of 4 and 4.4 for lagging power factors of 0.8 and 0.6, respectively. The full-load copper loss is equal to the iron loss. Calculate (a) the lagging power factor at which the full-load regulation is maximum, and (b) the full-load efficiency at unity power factor. [Ans. : (a) 0.4472 lagging; (b) 96.15 %]

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

Distribution System

The final stage in the delivery of the electric power is the electric power distribution system. From the transmission system to the individual customers it carries electricity. The distribution system is connected with the transmission system and is used to lower the voltage of the transmission to medium voltage in the range of 2 kV to 35 kV with the help of transformers. This medium voltage to the distribution transformers located near the customer's premises is carried by the primary distribution system lines. These distribution transformers in turn lower the voltage to utilization voltage used in lightings, household appliances, industrial equipments etc. Through secondary distribution lines often several customers are supplied from one transformer. It is through service drops, the commercial and residential customers are connected to the secondary distribution system lines. Customers who demand a larger amount of power can be connected directly to the primary distribution system level or the sub-transmission level.

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30. A single phase transformer has percentage regulations of 4 and 4.4 for lagging
power factors of 0.8 and 0.6, respectively. The full-load copper loss is equal to the
iron loss. Calculate (a) the lagging power factor at which the full-load regulation is
maximum, and (b) the full-load efficiency at unity power factor.
[Ans. : (a) 0.4472 lagging; (b) 96.15 %]

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