Transmission lines are an important part of the power system. The cost and life of a transmission line depend primarily on the material used to make the transmission line conductor. The most important and suitable material for transmission line conductors is copper because of its high electrical conductivity and high tensile strength. More importantly, it has good ductility. The only limitation is its cost. The most widely used material in transmission lines is aluminum.
Aluminum has sufficient electrical conductivity. Lighter weight. This reduces the weight of the conductor and reduces sagging. The only limitation is its low tensile strength. To overcome this limitation, steel cores are used to increase the tensile strength of aluminum conductors, such as in ACSR (Aluminum Conductor Steel Reinforced) conductors.
ACSR conductors are very popular in high-voltage overhead transmission lines. The selection of the appropriate material for the transmission line depends on –
Desired electrical performance
Required mechanical strength
Local conditions
Material costs
