为提高超磁致伸缩致动器（GMA）偏置磁场的均匀度, 设计了叠堆式超磁致伸缩致动器（SGMA）, 建立了SGMA的磁场分布模型, 并对模型进行分析研究。首先, 通过分析传统GMA偏磁施加方式的特点和不足, 采用永磁体和GMM棒交替排布的结构形式, 设计了SGMA; 然后, 将磁路模型和毕奥-萨伐尔定律相结合, 建立了能够准确描述SGMA磁场特点的磁场分布模型; 接着, 利用所建立磁场分布模型分析了不同参数对SGMA磁场分布特征的影响, 提出了SGMA结构设计方法; 最后, 通过实验完成了模型验证。结果表明: 采用本文建立的模型描述SGMA磁场分布时, 最大相对误差低于4%; 在预测SGMA的输出位移时, 最大相对误差低于5%。该模型有助于准确刻画SGMA的工作状态, 提高SGMA的系统精度, 并为SGMA结构设计提供参考依据。

In this paper, a kind of Stack Giant Magnetostrictive Actuator (SGMA) was designed, then the magnetic field distribution model of SGMA was established, and analytical research on model was conducted to increase uniformity of bias magnetic field of GMA. Firstly, given the characteristics and drawbacks of infliction way of bias magnetic field in traditional GMA, structural form of alternative arrangement for permanent magnet and GMM rod was adopted to design SGMA. Then by combining magnetic circuit model with Biot-Savart law, magnetic distribution model can accurately describe magnetic feature of SGMA was establish. Subsequently, the influence of different parameters on magnetic field distribution feature was analyzed on established model, and structural design method of SGMA was proposed. Finally, model verification experiments were conducted. The result indicates: maximum relative error is lower than 4% when using established model to describe magnetic field distribution of SGMA; maximum relative error is lower than 5% at the time of predicting output displacement of SGMA. The established model in this paper can describe work state of SGMA accurately, increase system precision of SGMA and provide reference basis for structural design of SGMA.