Asmall part of a power systems is shown in the single-line diagram in Figure 1. Grid 330 kV X=10 Q Transformer 1 to 180 MVA 330/132 kV X=8% Overhead transmission line 100 km long x = 0.05 02/km Figure 1 Part of a power system Transformer 2 Load 150 MVA 132/11 kV X = 5% (112+j84) MVA (a) Briefly explain why over-head transmission lines are used for long distance transmission of electricity instead of underground cables. (b) What type of support would you recommend for the overhead transmission line in Figure 1? Briefly describe this type of support, clearly stating why you think it is the most suitable support for the overhead line in Figure 1. (e) Calculate the load voltage if the grid voltage is 330 kV. (c) Calculate all the impedances in the power system in per-unit using a common base power of 200 MVA. (d) Sketch an impedance diagram of the power system and calculate the total impedance between the source and the load in per-unit.

Asmall part of a power systems is shown in the single-line diagram in Figure 1. Grid 330 kV X=10 Q Transformer 1 to 180 MVA 330/132 kV X=8% Overhead transmission line 100 km long x = 0.05 02/km Figure 1 Part of a power system Transformer 2 Load 150 MVA 132/11 kV X = 5% (112+j84) MVA (a) Briefly explain why over-head transmission lines are used for long distance transmission of electricity instead of underground cables. (b) What type of support would you recommend for the overhead transmission line in Figure 1? Briefly describe this type of support, clearly stating why you think it is the most suitable support for the overhead line in Figure 1. (e) Calculate the load voltage if the grid voltage is 330 kV. (c) Calculate all the impedances in the power system in per-unit using a common base power of 200 MVA. (d) Sketch an impedance diagram of the power system and calculate the total impedance between the source and the load in per-unit.

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

Chapter14: Power Distribution

Section: Chapter Questions

Problem 14.9P

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