Piezoelectric Multi-Frequency Nonlinear MEMS Converter for Energy Harvesting from Broadband Vibrations

This paper proposes a MEMS piezoelectric converter for energy harvesting from vibrations which exploits nonlinear effects to broaden the operating bandwidth. The converter is composed of an array of cantilevers with different geometric dimensions. Piezoelectric layer and electrodes have been deposited on the cantilevers by a custom low-curing temperature post process. Nonlinearity is achieved by the magnetic interaction of a magnet and ferromagnetic particles deposited on the cantilever tips. Preliminary results show that the converter behaves like a nonlinear system and a downshift of the resonant frequency of the cantilevers with respect to the linear resonant frequency is observed, as expected.