Analytical model of high-voltage transmission line subjected to the downburst wind with rainfall

Abstract

There have been many reports recently on unanticipated galloping and collapse accidents of tower-line systems due to downburst wind with rainfall. Although wet downburst is characterized by high-velocity wind with rainfall, very little research work is involved with galloping of high-voltage transmission line induced by the downburst wind with rainfall. Thus, this article proposes a preliminary theoretical study aiming to provide an analytical model of the high-voltage transmission line subjected to the downburst wind with rainfall to explain some phenomena observed from field measurements. Through wind or rain–wind tunnel experiments, we obtained aerodynamic characteristics of the high-voltage conductor with different yaw angles and rainfall rates. Considering the variations of several factors such as wind velocity, rainfall rate, yaw angle, and attack angle, the proposed analytical model was created by finite element method and central differences with the obtained aerodynamic coefficients of the high-voltage conductor. The theoretical results accord well with the experimental data. The analytical model enables better comprehension of the galloping of the high-voltage transmission line subjected to the downburst wind with rainfall.