ACSR Conductors in Power Transmission

ACSR is an acronym for Aluminium Conductor Steel Reinforced. These conductors are widely used in High Voltage Power lines.

Aluminium is a good conductor of electricity besides being cheap. However, its mechanical properties are not desirable. It is soft and cannot be hardened. It also has low tensile strength

This problem is resolved by providing a core of steel stranded cables inside an outer layer of aluminium stranded cables. The steel imparts excellent mechanical properties. Due to the skin effect, the bulk of the power is transmitted through the outer aluminium layer of the conductor which have better conductivity.

The amount of aluminium and steel strandings can be adjusted depending on the requirement for mechanical strength vis-a-vis electrical conductivity.

The conductors are sometimes impregnated with grease to protect against corrosion.

The strength of ACSR conductors is greater than that of copper conductors. The ACSR conductors also have a higher corona limit as they have a higer diameter.