Optimization of Conductor Configuration for UHV Double-circuits Transmission Lines

The optimization method for designer to select the conductor size and bundle-conductor configuration of UHV double-circuit transmission lines on a tower is presented. The effects of the bundle-conductor size and configurations, such as the subconductor diameter, the number of subconductors, the bundle diameter, the conductor heights, phase arrangements and phase spacings, on the environmental impacts of UHV transmission line are analyzed. Based on the method ,UHV line designer can select the configuration for two types of tower, drum-type and umbrella-type, as follows: the minimum conductor is determined and the horizontal spacing between two circuits and the vertical spacing of each circuit is adjusted in order to get the minimum horizontal spacing and minimum vertical spacing, with which the requirements for controlling EM (electromagnetic) environmental impacts would be satisfied. Corresponding curves are presented to offer the line designers.