Investigation of efficient piezoelectric energy harvesting from impulsive force
Sengsavang Aphayvong, Takeshi Yoshimura, Shuichi Murakami, Kensuke Kanda, Norifumi Fujimura
Abstract
Abstract This study investigated the electromechanical properties of MEMS piezoelectric vibration energy harvesters (MEMs-pVEHs) under various impulsive forces to discuss effective harvesting energy from random vibrations. MEMS-pVEHs with different resonance frequencies with an energy conversion efficiency close to the theoretical maximum were used. The output waveforms for various impulsive force could be fitted well with the dynamic model of pVEHs. The output energy density reached 34 nJ g −1 for an impulsive force with an acceleration of 8 m s −2 . To obtain high energy conversion efficiency, pVEHs should have a response time longer than the duration of the impulsive force; efficiency higher than 50% was obtained by an impulsive force with a short duration. Furthermore, the study investigated the pVEH requirements for impulsive force based on the results of numerical simulation.