Passively Self-Tuning Piezoelectric Energy Harvesting System

14th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications

物理学;能源学

Gregg, C.G.^1 ; Pillatsch, P.^1 ; Wright, P.K.^1

University of California, Berkeley, Department of Mechanical Engineering, Advanced Manufacturing for Energy, 2111 Etcheverry Hall, Berkeley

CA

94709, United States^1

关键词: Clamped-clamped beam;    Higher frequencies;    Magnification factors;    Piezoelectric energy harvesting systems;    Piezoelectric patch;    Real-world system;    Single frequency;    Vibrational energy harvesting;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/557/1/012123/pdf
DOI  :  10.1088/1742-6596/557/1/012123

来源: IOP

【 摘 要 】

Real world systems that are candidates for vibrational energy harvesting rarely vibrate at a single frequency, nor are these frequencies constant over time. This necessitates that vibration harvesters operate over a wide bandwidth or tune their resonance. Most tunable devices require additional energy or active control to achieve resonance over various frequencies. This work presents a passively self-tuning energy harvester that autonomously adapts its resonant frequency to the input without requiring additional energy. The system consists of a clamped- clamped beam, a movable proof mass, and a piezoelectric patch bonded to the underside of the beam. It demonstrated an open-circuit voltage output of 668 mVrms at 160Hz, 0.65g input excitation. Discrepancies between displacement and voltage magnification factors upon tuning at higher frequencies are discussed, as well as instabilities of the system and sensitivity to proof mass characteristics.