Output Power Optimization of Energy Harvester, Employing Segmentation of Its Electrodes

This research suggests employing electrode segmentation in order to avoid charge cancellation in the piezoelectric layers of harvester, which occurs, if strain nodes of vibrating harvester are covered by continuous electrodes. For the experimental investigations two types of piezoelectric energy harvester prototypes were produced from piezoelectric T107 H4E 602 plate, epoxy bonded to stainless steel substrate. The first (reference) harvester prototype posses no electrode segmentation, while electrodes covering piezoelectric material of second harvester were segmented. Segmentation of the second harvester was configured for its operation at the second resonant frequency – i. e., performed so, that the electrodes of piezoelectric material are not covering strain node of the second vibration mode. Experimental results revealed that segmented harvester prototype posses efficiency advantage as compared to the non-segmented counterpart – adding voltages, generated at each segment would result from 8% to 52% increase of maximum generated voltage.