Energy Harvesting and Optimization Using Active Resonance Fitting

Energy harvesting is an emerging topic recently. This harvested energy is used tooperate wireless sensors for different industrial monitoring and automation. Tomaximize the harvested energy in spinning systems, the harvester should vibrate atresonance for different spinning frequencies which can be achieved by active fitting.In this research, a novel methodology was developed by actively customizing thelength of vibrating element beam to manipulate its natural frequency according to thespinning frequency. Different models were investigated numerically andexperimentally to verify the proposed methodology. COMSOL Multiphysics softwareV5.1 was used to develop the numerical model, then and tip deformation and voltagedifference results were benchmarked. The numerical model was verifiedexperimentally by attaching a piezoelectric MIDE PPA 1021 which its vibratinglength was varied by changing the supporting length from 0 mm to 12 mm to aspinning object having variable frequency from 0-200 Hz. It is found that the MIDEPPA 1021 beam vibrated at its resonance throughout the specified spinningfrequencies. The proposed harvester can be applied in battery-free sensors being usedin automotives, wind-mills blades, and rotating machinery.