On the circuit solutions towards broadband and high-capability piezoelectric energy harvesting systems

Abstract

In the studies of piezoelectric energy harvesting (PEH) systems, literature has shown that the circuit solution has a significant effect towards the enhancement of energy harvesting capability under resonance. Some studies started to investigate its bandwidth-broadening effect recently. This paper provides a comprehensive comparison on the impact of circuit solutions towards the broadband and high-capability energy harvesting. The comparison is intuitively presented based on the equivalent impedance model. The joint dynamics and harvested power of the PEH systems using different interface circuits are thoroughly discussed. Simulation and experiments show good agreement with the analysis. It is shown that, within the existing circuit solutions, the currently proposed phase-variable synchronized parallel triple bias-flip (PV-P-S3BF) circuit provides the most extensive span of electrically induced damping and electrically induced stiffness/mass. By tuning the values of the two equivalent components in operation, the tasks of harvesting capability enhancement and bandwidth broadening can be simultaneously made by using PV-P-S3BF.