Wind induced motion on bundled conductors (Excluding ice galloping)Part B – Subspan oscillations

Subspan oscillations is a well-known phenomenon in High Voltage and Ultra High Voltage Overhead Transmission Lines (HV and UHV OHTL) [1]. It occurs on conductor bundles and it is due to the effect of the wake produced by the windward conductor on the leeward one. For this reason the phenomenon is also classified as wake induced oscillations, this phenomenon is a flutter type instability due to the coupling of vertical, horizontal modes in a frequency range between 0.5 - 2 Hz.