Why Use ACSR for High Voltage Transmission
 

 
 

Although the overhead conductor structure is simple, its role is extremely important. In the power network, the length of the line accounts for more than 90% of the total, especially in the 110kv-500kv high-voltage transmission and distribution lines. So why use steel core aluminum stranded for high-voltage power transmission?

The bare strands can be divided into three types from the structural composition. One type is a single wire made of a single metal material, such as aluminum stranded wire, copper stranded wire, aluminum alloy stranded wire, etc. The other type is to take the steel strand as the core wire to increase the tensile strength, and lay one or several layers of aluminum wire or aluminum alloy wire on the outside of the steel core aluminum strand; The third type is a stranded wire made of a bimetallic single wire, such as an aluminum-clad steel stranded wire.

When the voltage reaches 10kV, 30mm thick rubber insulation has lost its function (breakdown by high voltage). The reason for the high-voltage transmission of steel-cored aluminum stranded wire is that the density of aluminum is small. In the case of an equal volume, the quality of aluminum is smaller than that of iron and copper, and the electrical conductivity is better than that of iron. The reason for using the steel core is that the strength of aluminum is poor, soft and easy to break. The use of steel core can not only increase the strength of the conductor, but also do not affect the conductivity.