A study on the influence of design parameters on the power output characteristic of piezoelectric vibration energy harvester

This contribution derives a model of a vibration energy harvester in the form of a cantilever beam consisting of two piezoelectric layers, a single non-piezoelectric layer in-between and carrying a tip mass. The derived model discretizes the infinite-degrees-of-freedom system into an equivalent single-degree-of-freedom one (1-DOF) utilizing the Rayleigh-Ritz method. The output power is obtained as a function of the design parameters, including dimensions and material properties. At the resonance operation condition, the maximum power and the optimal load resistance formulas are obtained. Both are dependent on the design parameters and thus, for an optimal design of the harvester, the load resistance should be considered.