Prediction of wind-induced buffeting response of overhead conductor: Comparison of linear and nonlinear analysis approaches

Abstract

This study addresses the estimation of buffeting response of overhead conductor based on random vibration theory with closed-form formulations. Special attention is placed on the determination of static deformation with consideration of geometric nonlinearity, and its influence on the dynamic modal properties, aerodynamic modal damping and buffeting response. The dynamic response around the static equilibrium is separated into background and resonant components, which are calculated by using influence function and modal analysis, respectively. The aerodynamic modal damping ratios are estimated in closed-form formulations in which the influence of static swing of the conductor plane is explicitly accounted. Example studies presented in this study illustrate the accuracy and effectiveness of this linear buffeting analysis framework through comparison with nonlinear finite element model (FEM) analysis in the time domain. The importance of consideration of static deformation is revealed for the prediction of alongwind displacement and tension, especially, the resonant response component. The contributions of modal responses to various resonant responses are also examined.