Risk Analysis in Dynamic Thermal Overhead Line Rating

Making the most of the load capacity of the existing transmission and distribution system is now of great importance. The real value of the load capacity of an overhead line depends significantly on actual weather conditions. The method of line rating using the real risk analysis is described in the paper. The overhead line ampacity calculated using the risk evaluation has different values in comparison to traditional methods. The ampacity for the lower ambient temperature is usually set too high while the ampacity for the higher ambient temperature is set too low. The incorrectly calculated line rating can cause the significant conductor temperature and sag increase or incomplete utilization of the line load capacity