A novel parametrically excited non-linear energy harvester

In this study, a method utilizing parametrical resonance for harvesting energy from low-frequency vibrations was investigated. A pendulum-type architecture with electromagnetic induction as the energy conversion mechanism was proposed. A prototype device with a natural frequency of approximately 2 Hz was fabricated and evaluated experimentally. The performance of the device was studied theoretically and numerically. The results were validated by experiments. It was found that the numerical results were consistent with the experimental measurements, while the theoretical analysis slightly overestimated the power output. In the cases considered, the proposed device demonstrated qualitatively different behaviors as compared to a conventional linear device. Such difference, e.g. broadened bandwidth and increased power output at higher damping levels, may be advantageous in certain applications.

► Low-frequency energy harvesting based on parametrical resonance. ► Enlarged bandwidth compared to method based on linear resonance. ► Bandwidth increases as damping level decreases. ► Optimal damping level exists.