An Active Tuned Mass Damper for Vibration Reduction of Ultra-High-Precision Equipment

In this paper, an analytical method is presented to determine the optimal parameters of the symmetric tuned mass damper, such as the ratio between natural frequency of tuned mass damper and shaft (tuning ratio) and the ratio of the viscous coefficient of tuned mass damper (damping ratio). The optimal parameters of tuned mass damper are applied to reduce the torsional vibration of the shaft based on consideration of the vibration duration and stability criterion. The dynamic equations of the shaft are provided via Lagrangian equations, and the optimal parameters of tuned mass damper are derived by using the principle of minimum kinetic energy. Analytical and numerical examples are implemented to verify the reliability of the proposed method. The analytical and numerical results indicate that the optimal parameters of tuned mass damper have significant effects in the torsional vibration reduction of the shaft.

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Research on Seismic Response Vibration Hybrid Control of Hefei TV Tower

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.5197 ◽

2011 ◽

Vol 243-249 ◽

pp. 5197-5203

Author(s):

Zhi Qiang Zhang ◽

Fei Ma

Keyword(s):

Viscous Fluid ◽

Seismic Response ◽

Control Method ◽

Hybrid Control ◽

Spectral Characteristics ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Mass Damper ◽

Fluid Dampers ◽

Viscous Fluid Dampers

In this paper, Hefei TV Tower is used as an analytical case to examine the Hybrid control method on seismic response. Firstly, on the basis of the other’s work, a bi-model dynamic model is proposed to study the seismic response vibration hybrid control, using tuned mass damper and viscous fluid dampers. Then the optimal coefficient is obtained by considered the seismic response of upper turret as optimization objectives. According to analysis, it’s showed that the seismic responses of the tower are decreased greatly with tuned mass damper and viscous fluid dampers, and the vibration reduction effectiveness of the tower is sensitive to the spectral characteristics of earthquake wave.

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Study on the Stability of Non-Structural Element Using Active Tuned Mass Damper

Journal of Computational and Theoretical Nanoscience ◽

10.1166/jctn.2020.9165 ◽

2020 ◽

Vol 17 (7) ◽

pp. 3224-3230

Author(s):

Hong-Won Kim ◽

Dong-Gi Kwag

Keyword(s):

High Frequency ◽

Seismic Waves ◽

Passive Control ◽

Control Method ◽

Amplitude Ratio ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Structural Element ◽

High Frequency Region ◽

Mass Damper

Currently, the frequency of earthquakes is increasing in Korea, but due to the lack of appropriate seismic equipment, significant damage is expected. In order to solve this problem, active tuned mass damper will be developed to reduce earthquake damage in response to seismic waves, which are combined from low frequency to high frequency. In this paper, various control methods are introduced to reduce the amplitude ratio occurring at the 1st and 2nd natural frequencies for 3 DOF nonstructural elements. Through mathematical modeling, we confirm how each control method is applied and present the problems of the existing passive tuned mass damper and suggest the active tuned mass damper. To induce an active copper reducer, the response according to the control method can be predicted with a focus on the energy change rate. The active controller receives feedback from the relative displacement and relative velocity of the structure and uses it as a variable to set the control method. The passive control method and the active control method are compared through the simulation, and excellent control performance can be confirmed in the high frequency region as well as the second natural frequency. Vibration reduction performance was confirmed by each control method and the most ideal control method was selected. The optimum vibration reduction performance can be confirmed by using the signal function to always generate 180° of phase difference with respect to the speed of the structure. Not only earthquake but also mechanical vibration, wind load, etc., it can be used in all fields where damage is caused by excitation force inherent in various complex frequencies.

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Performance of TMDI for Tall Building Damping

Actuators ◽

10.3390/act9040139 ◽

2020 ◽

Vol 9 (4) ◽

pp. 139

Author(s):

Felix Weber ◽

Peter Huber ◽

Fredrik Borchsenius ◽

Christian Braun

Keyword(s):

Mass Matrix ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Tall Building ◽

Realistic Case ◽

Absolute Acceleration ◽

The Earth ◽

Mass Damper ◽

The Absolute ◽

Bending Modes

This study investigates the vibration reduction of tall wind-excited buildings using a tuned mass damper (TMD) with an inerter (TMDI). The performance of the TMDI is computed as a function of the floor to which the inerter is grounded as this parameter strongly influences the vibration reduction of the building and for the case when the inerter is grounded to the earth whereby the absolute acceleration of the corresponding inerter terminal is zero. Simulations are made for broadband and harmonic excitations of the first three bending modes, and the conventional TMD is used as a benchmark. It is found that the inerter performs best when grounded to the earth because, then, the inerter force is in proportion to the absolute acceleration of only the pendulum mass, but not to the relative acceleration of the two inerter terminals, which is demonstrated by the mass matrix. However, if the inerter is grounded to a floor below the pendulum mass, the TMDI only outperforms the TMD if the inerter is grounded to a floor within approximately the first third of the building’s height. For the most realistic case, where the inerter is grounded to a floor in the vicinity of the pendulum mass, the TMDI performs far worse than the classical TMD.

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Development and Performance Evaluation of Tuned Mass Damper for Vibration Reduction of 3MW Wind Turbine Tower

Korean Society of Hazard Mitigation ◽

10.9798/kosham.2016.16.5.261 ◽

2016 ◽

Vol 16 (5) ◽

pp. 261-271

Author(s):

Cheolgeun Seok ◽

◽

Sungkyung Lee ◽

Sukjun Joo ◽

Seungwoo Lee ◽

...

Keyword(s):

Performance Evaluation ◽

Wind Turbine ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Wind Turbine Tower ◽

Mass Damper ◽

And Performance

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Experimental Study on a Tuned-Mass Damper of Offshore for Vibration Reduction

Journal of Physics Conference Series ◽

10.1088/1742-6596/744/1/012045 ◽

2016 ◽

Vol 744 ◽

pp. 012045 ◽

Cited By ~ 2

Author(s):

Qiong Wu ◽

Xilu Zhao ◽

Rencheng Zheng

Keyword(s):

Experimental Study ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Mass Damper

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Parametric Study of Tuned Mass Dampers for Long Span Transmission Tower-Line System under Wind Loads

Shock and Vibration ◽

10.1155/2016/4965056 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 8

Author(s):

Li Tian ◽

Yujie Zeng

Keyword(s):

Frequency Ratio ◽

Damping Ratio ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Reduction Ratio ◽

Transmission Tower ◽

Tuned Mass Dampers ◽

Line System ◽

Long Span ◽

Mass Damper

A parametric study of tuned mass dampers for a long span transmission tower-line system under wind loads is done in this paper. A three-dimensional finite element model of transmission tower-line system is established by SAP2000 software to numerically verify the effectiveness of the tuned mass damper device. The wind load time history is simulated based on Kaimal spectrum by the harmony superposition method. The equations of motion of a system with tuned mass damper under wind load excitation are proposed, and the schematic of tuned mass damper is introduced. The effects of mass ratio, frequency ratio, damping ratio, the change of the sag of transmission line, and the robustness of TMD are investigated, respectively. Results show that(1)the change of mass ratio has a greater effect on the vibration reduction ratio than those of frequency ratio and damping ratio, and the best vibration reduction ratio of TMD is not the frequency ratio of 1;(2)the sag-span ratio has an insignificant effect on the vibration reduction ratio of transmission tower when the change of sag-span ratio is not large; and(3)the effect of ice should be considered when the robustness study of TMD is carried out.

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A low-cost and efficient d33-mode piezoelectric tuned mass damper with simultaneously optimized electrical and mechanical tuning

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x20966056 ◽

2020 ◽

pp. 1045389X2096605

Author(s):

Yong-An Lai ◽

Jin-Yeon Kim ◽

Chuang-Sheng Walter Yang ◽

Lap-Loi Chung

Keyword(s):

Optimal Design ◽

Energy Harvesting ◽

Piezoelectric Materials ◽

Low Cost ◽

Vibration Reduction ◽

Tuned Mass Damper ◽

Spring Stiffness ◽

Mass Damper ◽

Piezoelectric Stacks ◽

Optimal Values

This paper proposes a low-cost and efficient piezoelectric tuned mass damper (Piezo-TMD) for structural vibration reduction and energy harvesting. The Piezo-TMD consists of not only a proof mass, piezoelectric materials deforming in the d33 mode, and an electrical resistance, but also a spring and an inductor which enable the mechanical frequency and electrical frequency of the Piezo-TMD to be tuned to the structural resonance frequency. The equations of motion of a structure with the Piezo-TMD are derived, and an optimal design procedure for the Piezo-TMD is proposed to achieve a simultaneous maximum vibration reduction and energy harvesting. The performance of the Piezo-TMD is compared with that of a conventional optimal TMD installed in a footbridge under a pedestrian loading. The simulation results show that the Piezo-TMD performs better than the optimal conventional TMD in terms of vibration reduction while efficiently converting the absorbed mechanical energy to electricity with a high energy harvesting ratio. The innovative development of simultaneously tuning the mechanical and electrical systems leads to a much lower number of PZT stacks (saving 88% of piezoelectric materials in an illustrated case). The parametric study shows that the Piezo-TMD achieves the best performance when the optimal values for the spring stiffness, resistance, inductance, and the number of piezoelectric stacks are adopted from the proposed optimal design. If the selected spring stiffness and inductance are uncertain in a range between 0.94-1.07 times the optimal values, the vibration reduction performance of the Piezo-TMD remains similar, and the energy harvesting performance reduces less than 5%, as compared to the optimal performance. The effect of the number of piezoelectric stacks was also investigated. An insufficient number of piezoelectric stacks reduces the Piezo-TMD performance, and an excessive stack number does not improve the Piezo-TMD performance but increases the Piezo-TMD cost. Finally, the proposed Piezo-TMD employs inductance to significantly reduce the PZT stack number, thereby significantly reducing the cost of Piezo-TMDs.

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