Determine most economical size of a 3-phase line which suppliesthe following load at 10 kV. Daily load curve: (i) 1000 kW at 0.8p.f. lag for 10 hours, (ii) 500 kW at 0.9 p.f. lag for 8 hours and (iii)100 kW at unity p.f. lag for 6 hours. The cost per km of the erectedline is (8000 a+1500) where 'a' is the area of cross section of eachconductor in cm?. The combined interest and depreciation is 10%per annum of capital cost. Cost of the energy losses is 80 paisa perkWh. Resistivity of conductor material is = 1.72 x 106 Q-cm.

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Answered: Determine most economical size

Engineering

Electrical Engineering

Determine most economical size

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

Chapter8: Symmetrical Components

Section: Chapter Questions

Problem 8.25MCQ

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