Double conductors for transmission lines

Two overhead conductors a few inches apart used for each phase of a transmission line circuit reduce the reactance 20 per cent or more, thus, in many cases, increasing the power rating of the line. Also current carrying capacity and corona voltage limits are increased. However, costs with this type of construction are higher than with one larger conductor per phase. In addition to describing the advantages and disadvantages of double conductor lines, formulas are given in this article for the calculation of the electrical characteristics.