A real‐time alarm and early warning model for windage yaw of cat‐head type tower

Abstract

In recent years, accidents involving windage yaw flashover have been occurring on transmission lines frequently, affecting the operational security and the power supply reliability seriously. Moreover, it is expensive and difficult to reduce the windage yaw flashover by modifying the towers and transmission lines. Therefore, a real‐time alarm and dynamic early warning model for windage yaw of a cat‐head type tower is proposed in this paper from the perspective of operation. Starting with the side‐phase and the medium‐phase conductors of the cat‐head type tower, which are common and prone to accidents due to windage flashover, the windage yaw angle of the suspension insulator string in the real‐time alarm is provided by the inclination angle measuring instrument, while in the early warning scenario that is calculated based on meteorological forecasting information. Then the minimum gap between the line and tower is calculated. Finally, the model issues windage yaw alarms or warnings by comparing the calculated minimum gap with the minimum permissible clearance corrected by rain density and gives the operations corresponding to each alarm and warning. The correct predictions in three time intervals and the feasibility of the model can meet the requirement of engineering application. Because of the limitation of the numerical weather prediction (NWP) model and accuracy, the prediction result is not very good when the time interval is long; it could improve the prediction result when more accurate NWP data is employed. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.