Performance Analysis of Different Piezoelectric & Shim Materials on Bimorph Piezoelectric Energy Harvester

Micro-level energy generation from piezoelectric mechanism is a viable approach to convert atmospheric energy into electrical energy for powering tiny electronic devices. A Piezoelectric Vibration Energy Harvester (PVEH) can be thought of as a lever arm equipped with one or two layers of piezoelectric material (referred to as a unimorph or bimorph, respectively). This lever is attached to a vibrating structure, referred to as the host structure. In this work, the distributed parameter modelling method is followed to simulate a piezoelectric bimorph cantilever beam. This research has investigated the electrical power output from various combinations of piezo materials & shim materials. This study also has shed light on the variation of electrical output according to the density of different shim materials. Furthermore, this study includes the electrical output variation of PVEH by varying piezo layer widths, piezo material thickness, and shim thickness. The entire model is implemented in the MATLAB whilst the results being evaluated using it as well. From this study, it's found that, the piezo material PZT-5H produces higher power output than PZT-5A for the same type of shim material. Besides, for a specific PZT material, the output power increases with increasing density of the material used as shim. In addition, for a given piezoelectric energy harvester shape, the maximum electrical power output is achieved only for certain values of the thicknesses of the PZT and shim materials.