Dynamic Thermal Line Rating Estimation Using Live Regional Weather Data

The ampacity (thermal rating) of an overhead conductor depends on the meteorological conditions around the conductor and is time-varying. The estimation of the dynamic thermal line ratings (DTLRs) of regional overhead conductors is of great significance for making efficient use of the transfer capability of regional power grids thus benefiting the security and economic performance of power systems. By using the historical hourly live regional weather data and the historical minutely micrometeorological data of the overhead conductor, the correlation and deviation distribution between these two datasets in air temperature and solar radiation are analyzed, then a DTLR estimation method using the live regional meteorological data is presented. The method can estimate the probability distribution of the thermal rating under the conservative assumption on wind conditions, thus providing information for operators to safely exploit the transfer capability of regional overhead lines. The case studies testify the validity of the proposed method, and the test results show that the method can significantly improve the thermal rating of the regional overhead conductor compared with the conventional static thermal rating.