Vibration dampers on AAC and AAAC conductors

The subject addressed is that Electricity Distribution companies often classify, for overhead lines, STOCKBRIDGE vibration dampers are for Transmission and plastic HELICAL vibration dampers are for Distribution. The problem is that, whilst distribution companies generally use smaller conductors than in transmission, the above statement is not true for all types of conductors. Because of the author´s involvement in the new IEC standards 62567 (Self damping of conductors) and IEC 62568 (Fatigue testing of conductors), further research has shown that in the absorption characteristics of aeolian vibration, the conductor self-damping plays an important role in the deployment of plastic helical or spiral vibration dampers. The AAC (All Aluminium Conductor) and AAAC (All Aluminium Alloy Conductor) have less self-damping than other conductors. [1] So for these types of conductors, AAC and AAAC, a STOCKBRIDGE or coulomb absorbing type vibration damper is better suited for energy absorption. Whilst the conductor diameter is never the governing factor in determining the size of vibration damper to be used, it is rather, the characteristic impedance of the conductor and the manufacturer´s known characteristics of their dampers to match. [2] So the lower CI values, less than say 50 N/m, the Helical Vibration Damper (HVD) may be better suited. Zm = (T.W/g)^0.5. The outcome of this paper is to provide a better vibration damping solution for electricity distribution companies´ overhead lines and prevent catastrophic failure and fires.