Nonlinear dynamic characteristics of giant magnetostrictive-piezoelectric vibration energy harvester subjected to stochastic excitation

Giant magnetostrictive-piezoelectric composite vibration energy harvester is a kind of novel vibration energy harvester. It is made up of giant magnetostrictive layer, substrate and piezoelectric ceramics, which is shown in Fig.1. Giant magnetostrictive material (GMM) has large magnetostrictive coefficient, and can enhance the deformation of piezoelectric material to improve the efficiency of power generation. Giant magnetostrictive-piezoelectric composite vibration energy harvester has many advantages, such as small size, high mechanical-magneto-electric conversion efficiency, long service life, and low cost, which make it be applied as green energy widely. Although various achievements have been reported, the theoretical results of the dynamic characteristics of giant magnetostrictive-piezoelectric composite vibration energy harvester are not abundant because of the complex nonlinear characteristics of giant magnetostrictive materials and piezoelectric ceramics. In this article, giant magnetostrictive material with large hysteretic loop is applied to induce the self-excited vibration of the vibration energy harvester, and the nonlinear coupling dynamic characteristics of giant magnetostrictive-piezoelectric composite vibration energy harvester subjected to stochastic excitation are studied.