Correction of the calculation method for resistance increment due to the proximity effect of bundled conductors

With the increasing demand for electrical power, Ultra High Voltage (UHV) presents significant developmental opportunities due to its vast transmission capacity and extensive range. Bundled conductors are utilized in transmission lines to reduce losses caused by electronic corona, but their AC resistance deviates from that of a single conductor due to the proximity effect. Therefore, it is crucial not to oversimplify bundled conductors as merely an amalgamation of multiple single conductors. This paper first explains the principle of proximity effect and then presents a calculation methodology for the incremental resistance caused by this phenomenon. Finally, based on empirical findings, we refine the existing calculation methodology and demonstrate that the correction coefficient for relative resistance increment attributed to proximity effect depends on operating temperature and conductor separation distance rather than specific types of bundled conductors.