A test bench for characterization of piezoelectric frequency up-converting energy harvesters

Abstract

This work focuses on the design and realization of a test bench used to characterize the performances of the piezoelectric cantilever for frequency up-converting energy harvesters. A test bench is completed by combining a frequency up-converter with an oscilloscope (Tektronix TD 3032B). The frequency up-conversion mechanism achieves the excitation on a piezoelectric cantilever through an interaction between a permanent magnet and an iron bar. In the mechanism design, the air gap between a permanent magnet and an iron bar is analyzed by Finite Element Method (FEM). After the design is verified, a test bench is fabricated and then validated with experimental study by testing the performances of a PZT-5H bimorph (T220-H4-503X, Piezo Systems, Inc.); the considered performances are resonant frequency, average output power, total output energy and energy conversion efficiency. The experimental results demonstrate that a fabricated test bench is satisfactory.