the construction of new transmission lines and the establishment of new transmission corridors is rendered difficult due to the increasing real-estate costs and continued opposition to new transmission lines. The costs, on a per megawatt-mile basis is estimated by this article, aimed at uprating the transmission capacity without increasing the footprint of transmission.

MODEL OF AC TRANSMISSION LINES
Parameters Specifying ElectricalModel and Characteristics
the electrical model and characteristics of AC transmission lines are the following:
-1) Admittance and Impedance
The single-phase equivalent of a transmission line can be shown by the pi network. an inductance in series with a resistance forms the series element. The resistivity of the conductor determines the resistance and the inductance
depends primarily on the spacing of the conductors.
-2) Losses:
electrical losses is produced by the current flowing in the line resistance. The current flow and ambient conditions determines the temperature rise.
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