Optimization of Array of Tapered Piezoelectric Energy Harvester

This paper addresses two issues of piezoelectric harvesters, which are the narrow bandwidth and the low power at ultra-low frequencies through the optimization of two proposed designs of arrays, one consisting of rectangular beams and the other of tapered beams using finite element analysis using COMSOL Multyphisics6.2. To ensure a reliable results a comparison between the natural frequency obtained from the finite element method and that derived through the analytical model stated in literature. It was found that the tapered design gave peak power almost 10 times the rectangular one with a value of 0.67 mW at a natural frequency of 3.22 Hz for the tapered harvester and 0.073mW at a resonant frequency of 3.2068 Hz, competing with this value with more complex designs of harvesters.