A novel piezoelectric energy harvester using a multi-stepped beam with rectangular cavities

Abstract

In vibration-based piezoelectric energy harvesters, one of the major critical issues is increasing the bandwidth and output voltage simultaneously. This manuscript explores a new technique for broadening the operating frequency range and enhancing the output voltage of the piezoelectric material-based energy harvester by appropriate structural tailoring. The wide bandwidth and the improvement in harvested output are accomplished by means of a multi-stepped cantilever beam shaped with rectangular cavities. The harvester is mathematically modeled and analyzed for modal characteristics. It was demonstrated from the outcome that the first two consecutive mode frequencies could be brought closer and the output power was large at both the resonant frequencies compared to the regular cantilever beam energy harvester. The results obtained from experimentation were in agreement with analytical results.