Characterization of Flexible Piezoelectric Cantilever in Vibration Energy Harvesting

Nowadays, the increasing intention in the research community on small sized electrical energy generators due to the wide use of wireless sensor networks and the drawbacks of conventional chemical batteries, such as their limited lifespan and large physical dimensions. Therefore, the principle of harvesting energy from solar power, electromagnetic fields, wind and the human body have been introduced as alternatives. Among these energy resources, wind energy is clean, renewable and can be easily turned into mechanical vibrations that can be used to generate electrical energy via vibration-to-electrical energy conversion mechanisms using electromagnetic, electrostatic and piezoelectric transducers. From these transducers, piezoelectric materials have received the most attention because of their higher conversion efficiency. Therefore, flexible piezoelectric cantilever was tested for characterized cantilever in vibration energy harvesting. The parameters of the cantilever such as length, width and thickness were varied and investigated for energy conversion and performance. The piezoelectric cantilever was designed and simulated using COMSOL Multiphysics 5.5 tool. The simulation result and performance of each design was compared. Performances were plot based on generated voltage vs applied vibration frequency. Result shows that generated voltage of 4.3V at applied vibration frequency of 155Hz was the most optimal result compared to the rest of the design for a piezoelectric cantilever with the width, length and height of 30mm, 20mm and 0.2mm respectively. This was ideal as most of the devices nowadays uses 5V supply and the small design allows the piezoelectric cantilever to be portable or even easily installed in projects that utilizes it.