Modelling and Simulation of Micro-electro-Mechanical Systems for Energy Harvesting of Random Mechanical Vibrations

We consider the problem of modelling and analyze nonlinear piezoelectric energy harvesters for ambient mechanical vibrations. The equations of motion are derived from the mechanical properties, the characterization of piezoelectric materials, and the circuit description of the electrical load. For random ambient vibrations, modelled as white Gaussian noise, the performances are analyzed through Monte-Carlo simulations. Recently proposed solutions inspired by circuit theory, aimed at improving the power performances of energy harvesters are tested. Our results show that circuit theory inspired solutions, permit to design energy harvesters with significant improved performances, also in the case of random vibrations.