面向磁致伸缩-电磁复合式能量采集器的压磁效应模型

Modeling of Piezomagnetic Effect for Magnetostrictive-Electromagnetic Hybrid Vibration Energy Harvester

摘要:

提出了一种简化的、能指导复合式能量采集器中磁致伸缩发电效应、电磁发电效应的最优性能输出的理论模型。在模型的建立过程中，首先研究了应力和磁场对Tb_0.3Dy_0.7Fe₂合金压磁效应的影响，讨论了单独应力和单独磁场作用下磁致伸缩材料内磁通密度的变化特性；其次，提出了基于预加载荷方法和基于冲击应力方法的理论模型思路，并分别探讨了2种模型建立方法在复合式能量采集器设计中最大压磁系数获取的准则；最后，完成了能量采集器的大压磁系数获取方法的可靠性试验，实验结果与理论设计的结果吻合较好。该模型能够快速、准确地获得不同应用环境下复合式能量采集器的压磁特性，并可用于获取大压磁系数的复合式能量采集器构造及设计。

关键词:振动能量采集器;模型与设计;磁致伸缩-电磁;压磁效应

Abstract:

A simplified computational model for obtaining large piezomagnetic effect of magnetostrictive-electromagnetic hybrid vibration energy harvester was presented. During the model establishment, the influence of compressive stress ?σ and magnetic field ΔH on the piezomagnetic effect of Tb_0.3Dy_0.7Fe₂ alloy was studied, and their separate influence on magnetic flux density ?B of magnetostrictive material was investigated. Then, two methods, pre-loads-based method and impact stress-based method, were used to discuss the optimal criterion of hybrid piezomagnetic effect for the fabrication of magnetostrictive-electromagnetic generator. Finally, the modeling accuracy for obtaining large piezomagnetic effect was testified, and the experiment and theoretical results were in good agreement. Results show that the modeling can efficiently and accurately obtain the piezomagnetic effect for hybrid magnetostrictive material-based harvester under different application environments, which is of significance for design and fabrication of magnetostrictive-electromagnetic hybrid vibration energy harvester for obtaining large piezomagnetic effect.

Key words:vibration energy harvester;model and design;magnetostrictive-electromagnetic hybrid;piezomagnetic effect