Optimized Power Output from Piezoelectric Flexure Element Driven by Low Frequency Vibration

Abstract

Energy harvesting is the process of capturing readily available energy and converting into usable energy. Among the many different types of energy harvesting methods, piezoelectric energy harvesting has become popular as piezoelectric materials have the ability to transform mechanical energy into electrical energy. This research is focused on obtaining and optimizing the output of commercially available piezoelectric device which converts mechanical energy into usable electrical energy. Moreover this research is focused on low vibrational frequency levels as random vibration sources in the environment such as buildings, machines, human body, and vehicles as these have low frequency characteristics. The ambient energy in the form of excitations and simple harmonic motions are captured and converted into a vibration through a mechanism. Then this vibration is converted into electrical energy by means of the piezoelectric element. In this research, output power of the piezoelectric energy harvester was measured for different vibration frequencies (0 to 50 Hz range) with different tip masses (1.45 g to 6.45 g range). By considering the experimental data, values for tip mass and vibration frequency are suggested to extract the maximum power output from the energy harvester. These values can be used for energy harvesting from low vibrational frequencies to obtain maximum power output where the vibration frequency of the source is changeable.