Wide-band piezoelectric resonance frequency energy harvester

Some of the piezoelectric devices work more efficiently around the resonance frequencies. Piezoelectric structures have the highest displacement and charge generation closer to the resonance conditions. In this study, a wide band energy harvester with a spiral metal plate was designed. Metal shim with various length were integrated with piezo ceramic rings in a spiral form. Each metal shim has its own resonance frequencies. Neighboring metal shim has also its own resonance frequency. Intriguingly, resonance frequency of each shim is close to each other to trigger each other vibration. With such a structure it will be possible to scavenge energy in vibrating structure with a wider frequency range. Resonance frequency of piezoelectric structures is depend on mass of piezoelectric ceramics and clamped metal shim geometry. Parametric studies were performed to investigate the optimal condition of such a structure.