A 3-phase transmission line operating at 33 kV and having a resistance of 5 2 and reactance of 20 Nis connected to the generating station through 15,000 kVA step-up transformer. Connected to the bus-bar are two alternators, one of 10,000 kVA with 10% reactance and another of 5000 kVA with 7-5% reac- tance. Calculate the short-circuit kVA fed to the symmetrical fault between phases if it occurs (1) at the load end of transmission line (i) at the high voltage teminals of the transformer [) 44,500 kVA (ii) 100,000 kVA]

A 3-phase transmission line operating at 33 kV and having a resistance of 5 2 and reactance of 20 Nis connected to the generating station through 15,000 kVA step-up transformer. Connected to the bus-bar are two alternators, one of 10,000 kVA with 10% reactance and another of 5000 kVA with 7-5% reac- tance. Calculate the short-circuit kVA fed to the symmetrical fault between phases if it occurs (1) at the load end of transmission line (i) at the high voltage teminals of the transformer [) 44,500 kVA (ii) 100,000 kVA]

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.44P: A 130-MVA,13.2-kV three-phase generator, which has a positive-sequence reactance of 1.5 per unit on...

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Concept explainers

Three-Phase Transformers

Three-segment transformers are a type of transformer used to transform voltages of electrical systems into three ranges. Two type transformers are shell-type transformer and core type transformer. In brief, it could be described because of the exquisite kinds of configurations.

Transformer

Ever since electricity has been created, people have started using it in its entirety. We see many types of Transformers in the neighborhoods. Some are smaller in size and some are very large. They are used according to their requirements. Many of us have seen the electrical transformer but they do not know what work they are engaged in.

Question

2. A 3-phase transmission line operating at 33 kV and having a resistance of 5 2 and reactance of 20 is
connected to the generating station through 15,000 kVA step-up transformer. Connected to the bus-bar
are two alternators, one of 10,000 kVA with 10% reactance and another of 5000 kVA with 7-5% reac-
tance. Calculate the short-circuit kVA fed to the symmetrical fault between phases if it occurs
(1) at the load end of transmission line
(ii) at the high voltage terminals of the transformer
[1) 44,500 kVA (ii 100,000 kVA]

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