Energy Harvesting From an Impulsive Load With Essential Nonlinearities
Vibration based energy harvesting, whereby mechanical energy is converted to electrical energy that can be stored and later used, offers the possibility of a long-term energy source under many realistic environmental conditions. This work considers an energy harvesting system based on the response of an attachment with strong nonlinear behavior. The electro-mechanical coupling is achieved with a piezo-electric element across a resistive load. When the system is subject to harmonic excitation, the harvested power from the nonlinear system exhibits a wider interval of frequencies over which the harvested power is significant, although an equivalent linear device offers greater efficiency at its design frequency. However, under impulsive excitation the performance of the nonlinear harvesting system exceeds the corresponding linear system in terms of both magnitude of power harvested and the frequency interval over which significant power can be drawn from the mechanical vibrations.