Theoretical modeling and analysis of two-degree-of-freedom piezoelectric energy harvester with stopper

摘要

Piezoelectric energy harvesting techniques provide a promising way to transform the vibration energy into electric energy. Since the voltage output peak can drop due to the frequency excitation moving away from the resonance region, the on broadening the bandwidth of operation frequency has drawn great attention. In the paper, a novel two-degree-of-freedom piecewise-linear piezoelectric energy harvester is proposed to achieve wide operation frequency bandwidth by combining the multimodal harvesting technique and nonlinear method. Based on the average method, the analytical solution of the proposed device is achieved. From analytical and experiment results, at an excitation acceleration of 0.3 g, as the excitation frequency is up sweeping, the system achieves frequency bandwidth operation of 7.4 Hz which is about 5.2 times higher to that of conventional two-degree-of-freedom linear harvester, and the power outputs for the first and second resonances can reach up to 429 mu W and 411 mu W, respectively. Due to the close agreement between the calculated values and experiment results, the analytical solution and the theoretical model could be applied to further MEMS fabrication process and optimized design. (C) 2016 Elsevier B.V. All rights reserved.