Nonlinear dynamics and control of the galloping of elastic structures is an important research topic that has been addressed in the present paper. Some recent research has used high-frequency excitation in controlling galloping oscillations under steady wind. However, galloping under unsteady wind is potentially more dangerous because of the presence of an additional parametric instability on top of self-excited oscillation. No scientific study is thus far available in the literature concerning the control of galloping under unsteady wind. The present paper investigates the efficacy of high-frequency excitation, both parametric and direct, for controlling unsteady galloping. Analytical and numerical methods are employed to understand the dynamics of the system with and without high-frequency excitation. A detailed nonlinear analysis of the problem reveals rich dynamic characteristics of the system under different types of possible aerodynamic damping profiles. Overall, it is shown that both direct and parametric high-frequency excitation can effectively control the galloping oscillation. Direct excitation can completely eliminate the periodic as well as quasiperiodic galloping arising due to unsteady wind. However, parametric excitation can only limit the oscillation amplitude.

弹性结构舞动的非线性动力学和控制是本文研究的一个重要课题。最近的一些研究使用高频激励来控制稳定风下的舞动振荡。然而，由于在自激振荡之上存在额外的参数不稳定性，在不稳定风下疾驰可能更危险。迄今为止，文献中还没有关于控制在不稳定风下疾驰的科学研究。本论文研究了高频激励（参数激励和直接激励）在控制非定常驰骋方面的功效。采用分析和数值方法来了解有和没有高频激励的系统的动力学。对该问题的详细非线性分析揭示了系统在不同类型的可能气动阻尼曲线下的丰富动态特性。总体而言，表明直接和参量高频激励都可以有效地控制舞动振荡。直接励磁可以完全消除非定常风引起的周期性和准周期性舞动。然而，参量激励只能限制振荡幅度。