擷取風能之壓電發電機設計

Abstract

近年來再生能源議題受到人們的密切討論，越來越多人研究如何將環境中的能量轉換成有效利用之能源。本研究利用壓電材料的特性，擷取環境中的風能，將它轉換成電能。研究所使用的壓電片為雙晶片，它是一個三層板的結構，利用能量法與漢彌頓定理來推導壓電片的運動方程式，之後代入邊界條件推導其自然頻率，最後利用推導結果計算壓電片的自然頻率，並且使用有限單元軟體的模態分析得到壓電片的振動模態及相應的頻率。本研究所設計的發電機構是在壓電片自由端裝上一薄板，然後把壓電片固定在一驅體上，使用電風扇產生風力，將風速分別為3m/s、4m/s、5m/s的風力施加在發電機構上，再利用數位電表量測發電電壓及電流，得到的最大電壓為1.14V，最大電流為9.42#westeur024#10^-6 A。

Recently, renewable energy is discussed intensely. More and more literature investigates how to transform ambient energy into useful energy. This study uses the characteristics of piezoelectric materials to acquire wind energy, and then transform into electrical energy. The piezoelectric bender used in our study is bimorph, which is a three-layer beam structure. This study uses the energy method and Hamilton's principle to derive the equation of motion. Boundary conditions are utilized to calculate the natural frequency of piezoelectric benders. The finite element method is carried out to obtain the vibration modes of a piezoelectric bender and its corresponding frequency. This study designs a generator that fixes a thin plate on the free end of a piezoelectric bender and fixes a bender on a metal strut. An electric fan was used to exert wind speeds at 3m/s, 4m/s, and 5m/s, respectively, on the generator. A digital multimeter was thus employed to measure the voltage and current. The maximum voltage is measured at 1.14V. The maximum current is measured at 9.42#westeur024#10^-6 A.