Fe-Ga合金换能器动态输出特性分析

Fe-Ga合金具有应变大、响应时间短、能量密度高、磁机耦合系数高、驱动方式简单等优点.Fe-Ga合金换能器在高频驱动电流下会产生涡流损耗.驱动电流频率越大,集肤效应越明显,涡流损耗越大,磁场分布越不均匀,从而影响换能器的输出位移和输出功率.首先基于麦克斯韦方程组分析了不同频率下Fe-Ga棒内的磁场分布,结合结构动力学模块分析了Fe-Ga合金换能器棒内的磁场分布,进而得到Fe-Ga合金换能器的输出位移和频率的关系.结果表明,所使用的Fe-Ga合金换能器共振频率为700 Hz,最大输出位移为6μm.

Analysis of Dynamic Output Characteristics of Fe-Ga Transducer

Fe-Ga alloy has the advantages of large strain, short response time, high energy density, high magnetic coupling coefficient and simple driving mode. Fe-Ga alloy transducer will generate eddy current losses with high fre-quency driving current. The larger driving current leads to more obvious skin effect,eddy current losses and inhomo-geneous distribution of magnetic field,which will affect the output displacement and power of the transducer. The distribution of magnetic field in Fe-Ga rod under different frequencies is analyzed based on Maxwell's equations. The magnetic field distribution in Fe-Ga transducer and relationship between output displacement and frequency are studied based on structural dynamics model of Fe-Ga transducer. The results show that the resonance frequency of the Fe-Ga transducer used in this paper is 700 Hz and the maximum output displacement is 6 μm.