Asmall part of a power systems is shown in the single-line diagram in Figure 1. Grid 330 kV X =10 Q Transformer 1 180 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 1 180 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

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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