Evaluation of potentially effective ways for increasing power capacity of existing overhead lines

The assessment of the efficiency of increasing power capacity of existing overhead lines (OHL) is essential under the demands for cost-effective and ecological solutions within the current competitive market. In this paper we provide the basics of a methodology that permits the calculation of conductors´ sag and ampacity at any temperature and power frequency, when the conductors are erected on a pre-specified OHL structure. This methodology takes a holistic perspective on the system performance and allows the calculations to be applied to even newly developed high temperature low sag composite conductors. The implementation of this methodology allowed the comparative analysis of the performance of conductors of different technologies and sizes erected on a 33 kV wood pole system. Results, among others, indicated that the novel conductors have better mechanical and electrical performance at normal operating temperatures, potentially permitting the operation of the system at 66 kV.