Comparative study of energy harvesting performance of magnetoelectric composite-based piezoelectric beams subject to varying magnetic field

Abstract

Magnetostrictive materials with good mechanical properties can effectively convert the alternating magnetic energy in the environment into mechanical vibrations via the magnetostriction effect. However, in previous studies, there are few discussions on the comprehensive mechanism of different magnetic field environments on magnetoelectric composite components. This paper firstly analyzed the variation rules of typical parameters in the magneto-electromechanical conversion process of two types of magnetoelectric composite components under the action of DC bias magnetic field and DC - AC dual magnetic field in detail by using COMSOL software. Then, we actually made two kinds of magnetoelectric composite components and verified the validity of the theoretical analysis through the self-built experimental system, and tested their performance in energy harvesting. The experimental results show that, under a harmonic excitation of 3 Oe magnetic field, the DC bias magnetic field of 120 Oe can increase the open-circuit voltage of the Galfenol alloy based piezoelectric cantilever from 0.495V to 10.68V, and the output power from 1.6μW to 42μW by 2525% with a matched external load of 50kΩ. Under the action of 100Oe DC bias magnetic field and 3Oe AC magnetic filed, the open-circuit voltage of nickel component increases from 0.117V to 0.837V, and the output power increases from 2.6μW to 23μW by 784.6% under the adaptation of 1000kΩ external resistance. The findings of this work reveal the effect of the coupled magnetic field for the magnetostriction for different materials and provide the guideline for the design of magnetostrictive energy harvesters.