考虑温度扰动的超磁致伸缩换能器电–磁–热–机耦合特性研究

Electrical-magnetic-thermal-mechanical Coupling Characteristics of Giant Magnetostrictive Transducer Considering Temperature Disturbance

超磁致伸缩电声换能器输入输出特性受到电–磁–热–机多场耦合作用的影响,呈现复杂的非线性。现有研究更多关注材料自身耦合行为,未能考虑换能器整体结构影响,如磁回路、材料切割后涡流和温度等,难以有效反映换能器整体非线性特性。该文在考虑漏磁和切割后涡流效应的基础上,建立非线性电–磁–热–机多物理场耦合下的换能器综合电路模型。该模型能够有效分析多参数耦合作用下的换能器输入–输出特性,并确定温度、偏置磁场、预应力与换能器工作性能间的映射关系;在此基础上,探究温度对换能器偏置点的扰动规律,并由此提出换能器最优输出策略;最后,搭建双端面电声换能器性能分析实验平台,以验证模型的有效性。实验结果表明:论文所提出模型能够有效追踪换能器输入–输出行为,且可在不同温度下,寻找最佳偏置点使得换能器输出性能最佳。

The input and output characteristics of giant magnetostrictive electroacoustic transducer are affected by the multi-field coupling effect,which presents complex nonlinearity.The linearized piezomagnetic equations have been adopted by most of the existing studies to analyze the coupling behavior,these studies cannot reflect the nonlinear characteristics of the transducer.Based on the consideration of magnetic flux leakage and eddy current effect after cutting,a comprehensive equivalent circuit model of the transducer was established in this paper.The model took temperature,bias magnetic field and pre-stressing into consideration.The influence of temperature on the offset point of the transducer was investigated,and the optimal output strategy of the transducer was designed.Finally,an experimental platform was built to verify the effectiveness of the model.Experimental results show that the proposed model could effectively track the practical input-output behavior of the transducer.Meanwhile,the optimal offset points at different temperatures can be found to achieve the best output performance of the transducer.