Investigation of piezoelectric harvester performance for several shape of piezoelectric using finite element method

Abstract

Energy harvesting is a prominent means of ensuring energy sustainability and among popular source to be harvest is the rainfall for the water supply and also electric from the vibration of the rain drops. Raindrop vibration is commonly harvested using piezoelectric method; hence a specific piezoelectric structure is required to properly convert vibration to electric output. Usually, a cantilever beam structure piezoelectric is used as converter element. For maximum power output, the piezoelectric cantilever beam must generate frequency vibration near at its resonant frequency. However, the cantilever beam structure has several types of shape that can generate different output at their resonant frequency. Further investigation on several geometries of piezoelectric energy harvesters is simulated using COMSOL software in order to select suitable design with maximum power generating performance. This paper present four different geometries of piezoelectric energy harvester which are basic shape, T shape, trapezoidal shape and exponential shape. The output voltage and current were investigated to obtain the optimum output based on the result of the simulation. The results indicated that the trapezoidal shape width 24mm produced the largest power which is 36.83%, 63.04 % and 78.80 % than basic shape width 16mm, T shape width 24mm and exponential shape width 32mm that generated power output at eigen frequency mode 1.