壓電調諧質量阻尼器於垂直振動減振與能量擷取

Piezoelectric Tuned Mass Damper for Vertical Vibration Reduction and Energy Harvesting

賴勇安(Yong-An Lai) ； 周維苓(Wei-Ling Chou) ； 鍾立來(Lap-Loi Chung)

《結構工程》 35卷3期 (2020/09) Pp. 63-84

https://doi.org/10.6849/SE.202009_35(3).0003

摘要

近年來人類對於能源的需求持續攀升，然而為因應氣候變遷，將迫使減少石化能源的使用，因此尋求更多更環保的能量來源，以因應未來需求，為當前各國的研究重點之一。由於土木結構與材料技術的發展，結構物設計建造越趨經濟，橋梁結構重量漸趨輕量，外觀也逐趨細長，結構週期也隨之延長，使得橋梁結構也較易受人行等外力激振。土木工程師為了有效降低此振動量，逐以加裝調諧質量阻尼器（Tuned Mass Damper, TMD）的方式，透過調諧質量阻尼器的振動頻率與結構自然頻率調諧，吸收結構的振動能量，並透過自身之阻尼器來消散傳入之振動能。然此能量為一綠色能源，如能量就此消散，實為浪費，有鑑於此，本文研究「壓電調諧質量阻尼器（Piezoelectric Tuned Mass Damper, Piezo-TMD）」，以壓電材料將吸收之機械振動能轉換為電能，以便進行能量擷取。本文首先提出壓電調諧質量阻尼器之模型，推導出壓電調諧質量阻尼器系統之運動方程式。與一般調諧質量阻尼器不同，壓電調諧質量阻尼器除了力學之運動方程式外，另有一電路方程式，且兩方程式互為耦合。本文之壓電調諧質量阻尼器設計目標為能量擷取的平均功率最大化，並以一人行橋結構進行數值模擬，結果顯示壓電調諧質量阻尼器具有與傳統調諧質量阻尼器相近之結構減振效果，並可將人行外力所引致之振動能轉為可再利用之電能。且模擬結果顯示，壓電調諧質量阻尼器除其機械之自然頻率需與結構相調諧外，其電路之自然頻率也需與結構調諧，方可使結構之振動能量有效利用共振效應轉移至電路上。

關鍵字

調諧質量阻尼器 ； 壓電材料 ； 能量擷取 ； 垂直振動 ； 最佳化設計

並列摘要

In recent years, the energy consumption has continually grown. However, due to climate change, the use of fossil fuel to generate electrical power forces to be reduced. Therefore, looking for environmental friendly energy sources is one of the current research priorities. Because of the development of civil engineering technology, the design and construction of structures turn into more economical. The weight of the bridge structure is becoming lighter, the appearance is accomplishing slender, and the structural period is therefore prolonged, making the bridge structure more susceptible to external forces such as pedestrian loads. In order to effectively reduce the vibration, civil engineers designed and installed Tuned Mass Damper (TMD). Through the tuning of the natural frequency of TMD to the structure, the vibration energy of the structure was absorbed and then dissipated by dashpot. However, this absorbed energy is a kind of green energy source to waste to be dissipated. In view of this, this article studies ＂Piezoelectric Tuned Mass Damper (Piezo-TMD)＂, which uses piezoelectric materials to convert the mechanical vibration energy into electricity for energy harvesting. This research proposes the model and derives the equation of motion of the Piezo-TMD system. Different from the conventional TMD, Piezo-TMD has a circuit equation in addition to the mechanical equation, and these two equations are mutually coupled. The design goal of the Piezo-TMD in this paper is to maximize the average power for energy harvesting, and the numerical simulations are carried out with a pedestrian bridge structure. The simulation results show that the Piezo-TMD achieves the similar performance of vibration reduction as the conventional TMD and thus the vibration comfort requirement can be satisfied. Moreover, the vibration energy is further transferred to electricity for harvest to verify the feasibility of Piezo-TMD. In addition to tuning the mechanical natural frequency of the Piezo-TMD, the natural frequency of the circuit also needs to be tuned to the structure, so that the vibration energy of the structure can be effectively transferred to the circuit by using the resonance effect.

並列關鍵字

tuned mass damper ； piezoelectric material ； energy harvesting ； vertical vibration reduction ； optimal design