Nonlinear Galloping Control of Transmission Line Conductors Based on Negative Stiffness Damped Cable System

Abstract

Transmission lines are prone to large-amplitude galloping under wind loads. To effectively suppress such vibrations, this study proposes the use of a negative stiffness damped cable system (NSDCS) to enhance the structural damping. First, a finite element model of a single-span transmission line is established based on a three-node cable element, and the influence of adjacent-span conductors is incorporated through boundary condition treatment. Furthermore, based on a nonlinear iteration method, a static and dynamic solution process for the nonlinear governing equations of the system is proposed, where the dynamic analysis takes into account the effect of the conductor’s self-excited force. Using this analytical framework, the damping performance of the NSDCS is evaluated, and the influence law of each key parameter of the NSDCS on its additional damping ratio is revealed. Finally, nonlinear wind loads are applied to the conductor to analyze and verify the anti-galloping effect of the device. The results show that for the present conductor model, the NSDCS can completely suppress galloping when the initial wind attack angle lies within the range of 30[Formula: see text]–57[Formula: see text].