Improvement of bandwidth of a vibration based piezoelectric energy harvester using a passive-tuning method

Abstract

Over the past decades, development of portable electronics has invoked the possibility of harvesting energy from the ambient environment for self-powered systems. One of the popular methods is to harvest energy from the ambient vibrations. The vibrations occurring in the immediate surroundings are seldom of a constant frequency. Thus, there is a need for vibration energy harvesters to efficiently tap this broadened bandwidth of frequency. This work consists of the study of a beam-mass system of piezoelectric energy harvester (PEH), based on the concept of passive self-tuning resonator for broadband power harvesting. This nonlinear harvester is developed from the linear counterpart by incorporating a sliding mass at the tip of the beam. Experimental parametric study is carried out to investigate the behavior of the proposed design for its enhanced applicability. A thorough experimental investigation consisting of a study of the linear and nonlinear cases is performed with varying lengths of the slider mass and thickness of the vibration PEH beam.