Vibration energy harvesting

Abstract

The field of energy harvesting has experienced significantly attention from the researchers over the past few years due to the tendency to produce self-powered electronic devices. Among various environment energy sources, vibration is the most ubiquitous in daily life and thus, it becomes a reliable source to convert into electrical energy through transduction mechanisms. Piezoelectric transduction with piezoelectric materials was adopted in this research because of their high power density. One main challenge in this field is the limited bandwidth of frequency of the conventional linear vibration energy harvester. Therefore, this study proposed a broadband 2-Degree of freedom (DOF) piezoelectric energy harvester (PEH) by introducing non-linear oscillations with a magnetic oscillator. Bi-stable configuration is investigated through harmonic and random excitations under different base of excitation levels. Dynamic characteristics of the non-linear system as well as its advantage compared to the conventional linear one are also evaluated. The optimum resistance to generate optimum power is first to be determined through various tests on different values of resistance and this value will then be applied to the harmonic and random tests. Besides that, optimization of non-linear configuration will be studied to enhance the efficiency of the energy harvester. By comparing and analyzing the data obtained, it can be concluded that the proposed non-linear 2-DOF PEH is able to enhance the efficiency of the energy harvesting system by increasing the power output as well as broadening the bandwidth.