Accurate ampacity determination: temperature-sag model for operational real time ratings

This report presents a method for determining transmission line ratings based on the relationship between the conductor´s temperature and its sag. The method is based on the ruling span principle and the use of transmission line tension monitoring systems. The report also presents a method of accurately calibrating the final sag of the conductor and determining the actual-ruling span length of the line sections between deadend structures. Main error sources for two other real time rating methods are also examined