Computer Model Calibration and Design Comparison on Piezoelectric Energy Harvester

Abstract

This paper presents a thorough study on a piezoelectric bimorph energy harvester which experiences a random vibration. Two different conceptual designs are considered for comparison of their power generation efficiency. For this comparison study, it is essential to construct a valid computer model and several model parameters (e.g., piezoelectric material properties) are calibrated based on repeated test data. The model calibration is performed in two steps with both mechanical and electrical responses. The resonant frequency is used for the mechanical response, while the voltage amplitude of a bimorph cantilever harvester is employed for electrical responses. The two conceptual designs, a general cantilever type and center-mounted plate type, are modeled using a finite element method with the parameters found in the calibration study, and power generation levels are calculated and compared. Advantages and disadvantages of each design are discussed for potential researchers.