Piezoelectric energy harvesting device in a viscous fluid for high amplitude vibration application

The fragile nature of ceramic piezoelectric cantilevers limits their ability to withstand high acceleration amplitudes in vibration energy harvesting applications. This study reports a potential solution, which is vibrating the fragile power generator in a viscous fluid. The changes in resonant frequency, Q-factor, damping ratio, and power output of a bimorph piezoelectric cantilever prototype, as well as the relationship of power output vs the vibration acceleration were investigated. The broadened application frequency spectrum and the increased maximum operational acceleration demonstrate the potential of the bimorph piezoelectric cantilever operating in a viscous fluid for high amplitude vibration applications. (C) 2008 The Japan Society of Applied Physics.