Hybrid piezoelectric-electromagnetic energy harvester for scavenging energy from low-frequency excitations. (4th July 2018)

• Record Type: Journal Article
• Authors: Fan, Kangqi; Tan, Qinxue; Liu, Haiyan; Zhu, Yingmin; Wang, Weidong; Zhang, Daxing
• Is Part Of: Smart materials and structures. Volume 27:Number 8(2018:Aug.)
• Publication Date: 2018-07-04
• Subjects: piezoelectric effect -- electromagnetic induction -- hybrid energy harvesting -- low-frequency excitation -- bi-directional excitation; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/aaae92
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: Capturing mechanical energy from our living environment is an effective approach for implementing self-sustained electronics. One of the key challenges is how to generate more electricity from the low-frequency and multi-directional excitations. To address this interesting issue, this paper reports a hybrid energy harvester (HEH) that consists of a piezoelectric energy harvester (PEH) and an electromagnetic energy harvester (EMEH), which can scavenge energy from both low-frequency and bi-directional excitations. The PEH is composed of two piezoelectric cantilever beams, each of which can deliver a peak power of approximately 0.13 mW when excited directly by a harmonic vibration of 0.8 g . A spherical magnet is utilized to not only trigger the PEH to function, which endows the PEH with bi-directional energy-harvesting capability, but also induce the coil to generate electricity, achieving the integration of EMEH with PEH. When the magnet is subjected to a sinusoidal excitation of 1.24 g, each beam of the PEH generates a peak power of 0.058 mW at 7 Hz and the coil outputs a peak power of 2.94 mW at 7.2 Hz. The HEH exhibits a better charging performance than the PEH or EMEH for charging a capacitor, and the fabricated HEH prototype can light up tens of light-emitting diodes (LEDs) when excited by hand-shaking vibrations.