Equivalent circuit modeling of patch-based piezoelectric energy harvesting on plate-like structures with AC-DC conversion

Abstract

The equivalent circuit modeling of the vibration-based energy harvesters for accurate estimation of electrical response has drawn much attention over the recent years. Different methods have been proposed to obtain the equivalent circuit parameters using analytical and finite element models of the piezoelectric energy harvesters. In such methods, the structure is a typical cantilever beam with piezoelectric layers under base excitation. As an alternative to beams, piezoelectric patch-based harvesters attached to thin plates can be considered due to the wide use of plate-like structures in automotive, marine and aerospace applications. Considering these needs, a multi-mode equivalent circuit model of a piezoelectric energy harvester integrated to a thin plate is developed in this study. Equivalent circuit parameters are obtained from analytical distributedparameter model of the harvester which covers the electromechanical coupling behavior of the piezoelectric patch and vibration of the host plate. The multi-mode circuit representation of the harvester is built via electronic circuit simulation software SPICE. Using the SPICE software, electrical outputs of the piezoelectric energy harvester connected to linear and nonlinear circuit elements are computed. Simulation results are then validated for the standard AC-AC and AC-DC configurations. For the AC configuration, voltage Frequency Response Functions (FRFs) are calculated for various resistive loads and they exhibit excellent agreement with the published analytical closed-form solution. For the fullwave rectifier configuration, simulation results of the DC voltage and power outputs are calculated for a wide range of load resistance values and compared with the analytical singlemode expression of the harvester in the literature.