Performance of a dual piezoceramic cantilever for low frequency energy harvesting applications: modeling and experiment verification

Vibration-based energy harvesting is a growing field for generating low-power electricity to use in wireless electronic devices. These applications are usually in an environment of abundant low frequency vibration, which can be collected through an appropriate energy conversion structure. However, traditional energy conversion architectures such as cantilever-cantilever type or spring-mass type have the problem of high working frequency and narrow bandwidth (limiting its use and far from the frequency found in the surrounding environment). To overcome these challenges, this work proposes a study of a piezoelectric vibration energy harvester based on a dual cantilever structure. The energy harvesting system is designed, analyzed and verified with the finite element analysis method and an experimental study. The results show that the bandwidth is enlarged of 30 Hz and a power is generated and equals to the sum of the power generated by each cantilever (190 nW) with an output voltage supplying a resistive load of 110 KΏ.