Design and Optimization of Quadrilateral Shaped PVDF Cantilever for Efficient Conversion of Energy from Ambient Vibration

This paper addresses an efficient way of conversion of ambient vibrational energy to electrical by structure optimization of piezoelectric film. Polyvinylidene fluoride has been used for this study. The effects of shape variations of cantilever beam with multilayer configuration based on Euler-Bernoulli theorem without considering the proof mass attached at the free end has been investigated in this paper. Most of piezoelectric vibrational energy harvesters are designed considering the presence of proof mass and in this paper it has been tried to convey the idea, that with the new optimized shape, the cantilever itself can behave as a flexible proof mass for energy enhancement. The possibility of harvesting energy from three different geometries: 1) near edge width quadratic (NEWQ), 2) half quadratic (HQ), and 3) Trapezoidal has been presented. Scanning electron microscopy is used to measure the thickness of the various layers. The NEWQ design shows the best performance in terms of power and resonance frequency (fr<; 200 Hz) compared with the others. Here, the study of the piezo-film models using finite element method simulation software (COMSOL Multiphysics optimization module) and experimental validation are also presented. Using the models, the generation of voltage/power has been analyzed under various excitation frequency and load resistance. Moreover, stress/strain distribution and the displacement have also been highlighted in this paper.