A comparison between several vibration-powered piezoelectric generators for standalone systems

This paper presents a comparison between four vibration-powered generators designed to power standalone systems, such as wireless transducers. Ambient vibrations are converted into electrical energy using piezoelectric materials. The originality of the proposed approaches is based on a particular processing of the voltage delivered by the piezoelectric material, which enhances the electromechanical conversion. The principle of each processing circuit is detailed. Experimental results confirm the predictions given by an electromechanical model: compared to usual generators, the proposed approaches dramatically increase the power of the generators.