A multi-beam piezoelectric harvesting system with both electrical and mechanical coupling among piezoelectric beams

This paper develops a novel multi-beam harvesting system with both electrical and mechanical coupling among piezoelectric beams. The harvesting system integrates multiple piezoelectric bimorphs (PBs) with different thicknesses into a system, bimorph beams are not only connected electrically in series or in parallel but also connected mechanically with springs at ends. Effect of spring stiffness for two connecting patterns among PBs, in series and in parallel, on improving energy harvesting performance is discussed in detail. Numerical results show that the end spring connection can effectively broaden the frequency-band of the harvesting structure and shift the operating frequency-band to match with the frequency of driving forcings.