A small plant produces electric energy and, through a transformer, sends it out over the transmission lines at 50 A and 20 kV. The line reaches a small town over 25 km long transmission lines whose resistance is 1.2 ΩΩ/km. a) What is the power loss in the lines if the energy is transmitted at 20 kV? 75 b) What should be the output voltage of the transformer to decrease the power loss by a factor of 15? Assume the transformer is ideal. c) What would be the current in the lines in part b)?

A small plant produces electric energy and, through a transformer, sends it out over the transmission lines at 50 A and 20 kV. The line reaches a small town over 25 km long transmission lines whose resistance is 1.2 ΩΩ/km. a) What is the power loss in the lines if the energy is transmitted at 20 kV? 75 b) What should be the output voltage of the transformer to decrease the power loss by a factor of 15? Assume the transformer is ideal. c) What would be the current in the lines in part b)?

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 3.57P: A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when...

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