Optimising proof mass for cantilever based piezoelectric energy harvester

Abstract

In this paper the authors propose on optimising the proof mass and device dimensions on the output (voltage, current, power) of a cantilever bimorph based piezoelectric energy harvester using COMSOL multi-physics software. A detailed study of the dimensions of proof mass of the piezoelectric energy harvesters, based on geometry (length, height, and width), material, position and load resistance, had been carried out. The two basic geometries, rectangle, and pyramid were selected to show the influence of proof mass geometry on piezoelectric energy harvester output. The work compared the effect of output with varying proof mass material such as copper (Cu), tungsten (W), palladium (Pd), platinum (Pt), and silver (Ag). Studies show that proof mass placed at the tip with large height (2 mm) in a rectangular shape made of copper gives better output voltage, current, and power of 0.66 V, 55 µA, and 36.4 W respectively.