Daily Thermal Rating Calculation of Overhead Conductor Driven by Meteorological Data

Abstract

At present, the static thermal rating (STR) used for overhead wires is calculated under the assumption that relatively unfavorable meteorological conditions occur simultaneously, which limits the efficient forthputting of transmission lines to a certain extent. Therefore, this paper proposes a calculation method to analyze the daily distribution of thermal rating driven by meteorological data to release the load capacity of the transmission line. Firstly, the distribution of thermal rating at daily time scales is calculated based on IEEE738, and then the distribution of ratings can be counted by Parzen-window technology. Then, the static thermal rating can be converted into the seasonal, monthly or daily values, as the time scale of the thermal rating is shortened. Finally, the operational risk assessment is evaluated combined with the actual operating parameters of the wire. The example shows that the proposed method can determine the appropriate thermal rating conveniently at daily time scale according to the allowable operational risk of the power system, as well improve the load capacity of overhead lines.