Applicability of Dynamic Thermal Line Rating for Long Lines

Abstract

With an increased focus on renewable power generation, dynamic thermal line rating is being investigated as a way to connect the new intermittent generation to the grid without needing to build additional infrastructure. Traditionally, dynamic thermal line rating is only applied to thermally limited lines. This paper expands this notion by taking advantage of the relationship between temperature, conductor resistance, and voltage drop across a line; to increase the rating of non-thermally limited lines. This investigation is carried out with changes to the thermal limit to demonstrate how the intersection between thermal and voltage limits changes when resistance is considered. The sensitivity of the rating to different environmental parameters and the impact of changing the voltage limit are also investigated.