A single phase 100KVA 4000/240V 60 Hz. transformer, whose impedance refered to low voltage side is 0.0015+ j0.0020 is connected to the load end (load side) of a feeder line whose impedance is 0.28+ j0.580 Find the voltage at secondary terminals of the transformer when the load connected its secondary draws rated current from the transformer and the power factor of the load is 0.8 lagging. The sending end (source side) of the feeder line is connected to 4000V voltage level.

A single phase 100KVA 4000/240V 60 Hz. transformer, whose impedance refered to low voltage side is 0.0015+ j0.0020 is connected to the load end (load side) of a feeder line whose impedance is 0.28+ j0.580 Find the voltage at secondary terminals of the transformer when the load connected its secondary draws rated current from the transformer and the power factor of the load is 0.8 lagging. The sending end (source side) of the feeder line is connected to 4000V voltage level.

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 3.51P: The ratings of a three-phase three-winding transformer are Primary(1): Y connected 66kV,15MVA...

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An infinite bus, which is a constant voltage source, is connected to the primary of the three-winding transformer of Problem 3.53. A 7.5-MVA,13.2-kV synchronous motor with a sub transient reactance of 0.2 per unit is connected to the transformer secondary. A5-MW,2.3-kV three-phase resistive load is connected to the tertiary Choosing a base of 66 kV and 15 MVA in the primary, draw the impedance diagram of the system showing per-unit impedances. Neglect transformer exciting current, phase shifts, and all resistances except the resistive load.
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