Methodology for optimizing the capacity and costs of overhead transmission lines by modifying their bundle geometry

The electrical power systems demand is continuously growing, in such a way that it is necessary to pursue methods to increase the overhead transmission line power capacity for single circuit lines. In this paper, it is proposed a methodology to increase the line energy transport capacity at lower costs. The enhancement is done by modifying the bundle geometry by using a heuristic optimization process divided into two steps. Firstly, a fixed bundle geometry is generated. Secondly, this form is modified seeking the optimization of line energy transmission capacities. During all process, electrical, mechanical and economical analyses are performed. As result, single circuit line geometries with almost 26% higher surge impedance loading than the original, significant costs reduction (50%), moderate bundles size (smaller than 2.5 m), similar electric fields within the conductors of the bundle, smaller right of way, and similar transient response were obtained. Thus, compared with regular single circuit transmission lines, these new transmission lines have a lower overall cost and environmental impact. Finally, a transient analysis of the proposed transmission line is presented.