A high-efficiency curved panel energy harvester featured by reduced stress concentration

Abstract

Currently, most energy harvester designs focus on improving the efficiency of harvesting, with less attention paid to fatigue damage. In this study, a novel piezoelectric energy harvester with a curved panel is proposed. The curved panel of the harvester exhibits a bistable behavior during the deformation process so that the vibration energy can be efficiently converted into electricity. Moreover, the fatigue damage caused by stress concentration can be significantly alleviated by the real-time stress change of each curved panel. To optimize the power generation efficiency of the harvester, the design considered the influence of a number of key parameters, including panel thicknesses, mass block, excitation frequency and load resistance. Experimental results show that the maximum peak-to-peak and root-mean-square voltages under open-circuit conditions can respectively reach upmost 24.8 V and 5.66 V for the harvester with a piezoelectric film in a dimension of 30 mm × 12.1 mm × 0.28 μm, and the maximum power reach 129.4 μW. The proposed harvester has great potential for power generation and application, which provides a reference for collecting vibration energy in environment.