Corona loss of the bundle conductors on EHV/UHV AC power lines under sandy and dusty conditions in high-altitude areas

Abstract

Corona loss (CL) of bundle conductors is a key parameter to evaluate the economy and reliability of AC Power lines. In spring and autumn, sandstorms frequently occur in north-west China, the presence of sand particles affects CL characteristics on AC power lines. Based on a UHV corona cage built in Xining, Qinghai Province, China at an altitude of 2200 m, this study experimentally investigated CL of bundle conductors generally used in EHV/UHV power lines under sandy and dusty conditions. Furthermore, changes of CL with sub-conductor radii r, bundle number n, field strength E, dust concentration g, and particle size rd were revealed. It was found that CL quasi-linearly changed with increases in r2, n, and E2, CL non-linearly changed and showed a certain saturated trend with increases in rd and g. In addition, the empirical expression for calculating CL by considering r, n, E, g, and rd was proposed. Finally, CL of typical actual double-circuit UHV AC power lines on the same tower under sandy and dusty conditions in high-altitude areas was evaluated. The research results can provide references for evaluating the economy and conductor selecting on EHV/UHV AC power lines in high-altitude areas where sandy and dusty weather frequently occurs.