Exploring the Influence of Geometrical Parameters on Piezoelectric Vibration Energy Harvester: From Experiment to Simulation Investigation

Abstract

Vibrational energy has recently become one of the most sought-after targets and an ideal source of energy because of its widespread existence, and one of the effective methods of storing vibrational energy is to use piezoelectric. Nevertheless, the design of piezoelectric vibrational energy harvesting systems continues to be a challenging task, as the behavior of various subsystems influences the energy harvested. Most typical strategies concentrate on improving the piezoelectric system, while the effects of other subsystem in particular the substrate layer, are either simplified or not considered at all. Therefore, the paper is obliged to investigate a method to design a substrate layer for a piezoelectric vibrational energy harvesting system that is optimized to boost energy efficiency. In this study, a piezoelectric PZT-5A patch attached to a substrate cantilever beam with proof mass at the free end was modelled using finite element analysis (FEA) in ANSYS Workbench which was later verified through experiments. The proof mass, beam length, and PZT position were used as variable parameters in the studies. The preliminary results of FEA demonstrate that a 180 mm beam length with a 17 g proof mass and PZT-5A positioned in the middle of the beam produced a maximum voltage output of 4.75 V at 9.8 Hz. These results are in agreement with the experimental results even though there are discrepancies in terms of the peak width owing to damping. Thus, the implications of these findings lead to two conclusions: 1) the reliability of FEA as a tool for identifying the optimum design and cost-saving options and 2) a better understanding of how the geometric parameters of the substrate layer influence the performance of vibration energy harvesters.