Assuming a distribution substation SSO has a capacity of 30MVA with input - output voltages are 66KV - 9KV. SSO is feeding a square shapedarea A1 by 4 primary feeders where A1=4 km2 with load density D1=2000KW/Km2. the operating voltage of primary feeders was 5.2KV /9KV.After 30 years, the area fed by SSO will be enlarged to become circular shape A2 with radius R=L2 = 4KM (as shown in the figure). The loaddensity of the extended area (A2 - A1) remains the same of the old area. For info, all loads in area A1 and (A2-A1) are lagging with PF=0.8Area A2D2=01Area A1D1Area A1D1S1SSo12 = New FeederL1= Old FeederDue to the enlarging of served area, it is decided to change the line to line primary voltage. Assuming that number of feeders of the new areaA2 is 10 and using voltage square factor, The new primary voltage VLLnew that should be used in the new substation SS1 isSelect one:Оа. 2690KVOb. 23.90KVOc 24.90KVO d. 25.90KVOe.22.90KVO f. None of these

Due to the enlarging of served area, it is decided to change the line to line primary voltage. Assuming that number of feeders of the new area A2 is 10 and using voltage square factor, The new primary voltage VLLnew that should be used in the new substation SS1 is:

Due to the enlarging of served area, it is decided to change the line to line primary voltage. Assuming that number of feeders of the new area A2 is 10 and using voltage square factor, The new primary voltage VLLnew that should be used in the new substation SS1 is:

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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At a 220 kV substation of apowersystem, it is given that the three-phase fault level is 4000 MVA and single-line toground fault level is 5000 MVA. Neglecting the resistance and the shunt susceptances ofthe system The positive sequence driving pointeactance at the bus is:
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