Galloping Mechanism and Anti-Galloping Design of UHV Transmission Lines in Extreme Meteorological Environments

Intensifying extreme weather conditions have significantly increased transmission conductor galloping. To address this, this study proposes an anti-galloping composite inter-phase spacer arrangement for 1,000 kV AC UHV lines with a three-phase vertical configuration. Using a 4DOF nonlinear simulation model and the finite element method, multi-span conductor-insulator systems were analyzed to evaluate variations in minimum inter-phase distance. Results reveal that galloping severity and spacer efficacy correlate strongly with tension section span lengths, leading to five optimized arrangement schemes. Specifically, for spans below 300 m, installing 2 spacers (at 1/3 upper-middle and 2/3 middle-lower positions) achieves 96% suppression efficiency. For 300–360 m spans, 3 spacers (1/4, 3/4…