A 6.9 kV/600 V, multi-tap, single-phase distribution transformer is connected to the far end of a distribution line for which the rear end voltage is maintained at 6.9 kV. The equivalent impedance of the transformer referred to low voltage side is 0.05 + j0.25 Ω per phase. The impedance of each line is 1 + j2 Ω. It is required to maintain a terminal voltage of 600 V when the line current of 300 A at 80% pf lagging is delivered to the load. What approximate percentage tapping is required in the primary side? Neglect the changes in impedance due to changes in turns ratio. A. 94 % B. 92 % C. 90 % D. 88 %

A 6.9 kV/600 V, multi-tap, single-phase distribution transformer is connected to the far end of a distribution line for which the rear end voltage is maintained at 6.9 kV. The equivalent impedance of the transformer referred to low voltage side is 0.05 + j0.25 Ω per phase. The impedance of each line is 1 + j2 Ω. It is required to maintain a terminal voltage of 600 V when the line current of 300 A at 80% pf lagging is delivered to the load. What approximate percentage tapping is required in the primary side? Neglect the changes in impedance due to changes in turns ratio. A. 94 % B. 92 % C. 90 % D. 88 %

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 3.4P: A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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