High Voltage (Feb 2023)
Experimental study on dynamic response characteristics of isolated‐span transmission lines after ice‐shedding
Abstract
Abstract The dynamic response characteristics, including maximum jump height and unbalanced tension, of isolated‐span transmission lines after ice‐shedding are investigated by means of experiments. A reduced‐scale modelling method for ice‐shedding from conductor lines is presented and verified with numerical simulations and full‐scale test results in the literature. A parameter study on dynamic responses of isolated‐span conductors under three ice‐shedding scenarios, including whole span ice‐shedding, partial ice‐shedding and unzipping ice‐shedding, is carried out by means of reduced‐scale modelling tests. The effects of these parameters on the maximum jump height at typical positions and unbalanced tension in the tension tower are obtained. It is observed that the partial ice‐shedding scenario may be the worst situation for electrical insulation clearance rather than the whole span ice‐shedding scenario. Moreover, the position of maximum jump height along the span of isolated‐span transmission lines after ice‐shedding could be at around 2/5 of span length, which is different from the conventional opinion that the position is at the midpoint. The results may provide a foundation for the defining of the insulation clearance for an isolated‐span transmission line and the structure design of tension tower arms in an iced zone.