同轴集成式宏微复合驱动器的磁路建模分析与实验研究

Experimental Study and Magnetic Circuit Modeling Analysis of Coaxial Integrated Macro-micro Composite Actuator

针对精密定位工作台大行程与高精度特性间的矛盾问题,将音圈电机(voice coil motor,VCM)与超磁致伸缩驱动器(giant magnetostrictive actuator,GMA)结合,提出一种大行程、高精度特性的同轴集成式宏微复合驱动器。为优化驱动器的磁路结构,基于磁路法分别建立驱动器的宏动、微动及整体磁路模型,并采用有限元分析法,得到宏动永磁体结构、宏动磁轭相对磁导率以及宏动线圈电流对宏动磁路的影响规律和不同参数下宏、微磁场间的相互影响规律。为验证优化方案,在研制驱动器样机的基础上,搭建实验平台,测试驱动器的输出性能。研究结果显示:宏动永磁体采用6片瓦型结构,宏动磁轭的相对磁导率为400以上时,宏动力与宏动线圈电流之间近似成线性关系,且不同参数作用下,宏动磁场与微动磁场之间的相互影响均小于0.001Wb/m^(2),试制样机的宏动力最大可达53N,最大加速度可达6.7g,最大驱动行程达到47mm,最高定位误差仅为0.14μm。表明所提出的同轴集成式宏微复合驱动器的设计方案是合理可行的,为研发兼具高速、大行程和高精度特性的精密定位工作台奠定了理论与技术基础。

Aiming at the contradiction bet ween large-stroke,and the high-precision characteristics of precision positioning worktable,a design scheme of a coaxial integrated macro-micro composite actuator with high-speed,large-stroke,and high-precision characteristics was proposed by combining a voice coil motor with a giant magnetostrictive actuator.To optimize the magnetic circuit structure of the actuator,the macro,micro and overall magnetic circuit models of the actuator were established respectively based on the magnetic circuit method.The influence law of the macro permanent magnet structure,the relative permeability of the macro yoke,and the macro coil current on the macro magnetic circuit and the interaction law between macro and micro magnetic fields under different parameters were obtained by using the finite element method.To verify the optimization scheme,based on the development of the actuator prototype,an experimental platform was built to test the output performance of the actuator.The results show that when the permanent magnet structure is of six-tile type and the relative permeability of the voice coil motor is over 400,there is an approximately linear relationship between the macro-motion force and the macro-motion coil current,and the interaction between the macro-motion magnetic field and the micro-motion magnetic field is less than 0.001wb/m2 under the action of different parameters.The maximum macro-motion force of the prototype can reach 53N and the maximum acceleration can reach 6.7g;the maximum driving stroke is 47mm,and the maximum positioning error is only 0.14μm,which indicates that the design scheme of the coaxial integrated macro-micro composite actuator is reasonable and feasible,laying a theoretical and technical foundation for further precision positioning worktable with high speed,large stroke,and high precision.