Control of wind-excited towers by active tuned liquid column damper

Abstract

An active control system involving a tuned liquid column damper (TLCD) is developed for the vibration control of a single-degree-of-freedom tower subjected to wind excitation. This new control system will be referred to as the active tuned liquid column damper (ATLCD) system. It is found that the wind-induced response of the tower can be reduced substantially by the ATLCD system. The most efficient type of sensor is found to be the acceleration sensor when compared with displacement- and velocity-type sensors. To assess the effectiveness of such a control system, a comparison study is made between the ATLCD and the active–passive tuned mass damper (APTMD). In seeking the optimal control parameters for both systems, the norm of the root-mean-square of the system output under actual wind excitation, ‖ H‖ rms, is adopted as the objective function instead of the commonly used ‖ H‖ 2 (i.e., the norm of the system output under a unit white noise). The results show that the proposed ATLCD system is a good alternative to the APTMD system. Considering the potential advantages of the liquid column damper, the ATLCD system may be a better choice for vibration control of wind-induced towers.