Magnetically coupled piezoelectric galloping-based energy harvester using a tandem configuration

Abstract

Herein, we propose a piezoelectric galloping-based energy harvester that uses a magnetic coupling effect to improve its energetic performance. This proposed structure includes two elastic structures with bluff bodies arranged in a tandem configuration and a pair of repulsive magnets installed between the two bluff bodies to enable the use of their mutual interaction. A nonlinear coupled aero-electro-mechanical model is established using the extended Hamilton principle to gain a comprehensive understanding of the nonlinear dynamic behaviors of the proposed system. The mechanism of the magnetic interaction between the outer and inner bluff bodies was thoroughly investigated through time histories, phase portrait, and frequency spectrum analysis. The experimental results exhibited good agreement with the analytic results, highlighting that the present model is considerably accurate and reliable. Compared with the conventional system without the engagement of the magnetic coupling effect, a maximum overall average output power of 8.09 mW and power improvement rate of 65% could be obtained for the proposed energy harvesting system with the optimal magnetic gap distance. The proposed energy harvesting system is expected to be a promising alternative for the convenient and practical development of efficient wind energy harvesters.