Experimental study of coupled dynamic and electric characteristics of piezoelectric energy harvester under variable resistive load

The paper presents experimental study of dynamic and electric characteristics of cantilever-type bimorph piezoelectric energy harvester at the presence of varying resistive loads spanning from short circuit to open circuit conditions. Frequency response measurements of tip displacement and voltage output were performed in a setup with a differential laser Doppler vibrometer. Reported results include resonant frequency, tip displacement, quality factor as well as generated voltage, current and power. It is demonstrated that the magnitude of connected electrical load significantly influences power generated by the harvester as well as other characteristics. The trends in experimentally obtained data are analyzed and reasons behind them are discussed. Conducted experimental study allowed to characterize coupled mechanical and electrical performance of the standard piezoelectric energy harvester with well-defined geometric and material properties under variable electrical loading conditions. Measurement data will be used for verification and updating of the developed finite element model.