An experimentally validated double-mass piezoelectric cantilever model for broadband vibration–based energy harvesting

Abstract

Narrow bandwidth is the major challenge to today’s vibration-based energy harvesters. Compared with other broadband approaches that involve moving parts and control electronics, a double-mass piezoelectric cantilever beam provides a simple and reliable solution to widen the effective bandwidth as a vibration energy harvester. In this article, a continuum model of a double-mass lead zirconate titanate cantilever subject to sinusoidal base excitation is presented. First, the undamped equation of motion along with boundary and transition conditions is derived from Hamilton’s principle, followed by modal analysis that determines the eigenfunctions and natural frequencies. Next, the coupled electromechanical equations for sinusoidal base excitation are obtained. The output voltage and relative displacement are solved analytically. The frequency response function and mode shapes predicted by the model are validated against experiments.

A multi-degree of freedom piezoelectric vibration energy harvester with piezoelectric elements inserted between two nearby oscillators

“…This is achieved by adopting two cantilever beams connected with one proof mass, as this configuration took account of both translational and rotational degrees of freedom. Ou et al [14] presented an experimental study of a 2 DOF piezoelectric vibration energy harvesting system attached with two masses on one cantilever beam to achieve two close resonant frequencies. Zhou et al [15] presented a multi-mode piezoelectric energy harvester which comprised a tip mass called 'dynamic magnifier'.…”

A Novel Ropes-Driven Wideband Piezoelectric Vibration Energy Harvester

“…In the case of the multimodal harvesting technique, it is mainly based on the structure of beam arrays, which have different frequencies to match the wideband excitation's components, can be classified into unconnected mechanical structure systems [19][20][21][22][23]-connected mechanical structure systems using springs [24,25]-and multi-resonance systems [26][27][28][29][30][31]. Compared with a conventional single piezoelectric beam EH, much higher bandwidth of the EH can be realized by the multimodal harvesting technique.…”

Energy harvester for rotating environments using offset pendulum and nonlinear dynamics

“…Thus, for both linear and rotational systems, the narrow operating bandwidth can be a chief limitation. The following three main approaches to improving the bandwidth are the subjects of current research efforts: tuning the resonance frequency of the harvester during operation [17,18], implementing multimode oscillators [19], and employing nonlinear oscillators to widen the bandwidth [20]. These methods are equally applicable to rotational systems.…”