Vibration Control of Tower Structure by a Two-Dimensional Hybrid Dynamic Absorber.

In order to control the vibration of tower structures, this paper proposes a two-dimesional hybrid dynamic absorber that combines an electromagnetic actuator with a magnetic-damping-type dynamic absorber, and also shows a new method for making a reduced-order model. To control the vibration of a flexible structure like a tower using LQ control theory, it is ncessary to make a reduced-order model of the structure. However, the order reduction may cause a spillover instability problem, the effect of which can be ignored higher-order modes in a full-order structure. In this method, nodes of the higher-order mode are selected as set points for the model sensors. It is shown that the two-dimensional hybrid dynamic absorber can control two-dimensional vibrations, and spillover instability can be prevented easily using this method.