In this study,several types of linear actuators that adopt different permanent-magnet(PM)topologies are studied and compared.These linear actuators are based on the concept of PM magnetic screw transmission,which offe...In this study,several types of linear actuators that adopt different permanent-magnet(PM)topologies are studied and compared.These linear actuators are based on the concept of PM magnetic screw transmission,which offers high force density,high reliability,and overload protection.Using different magnetic configurations and assembly methods,these linear actuators are designed and optimized for a fair comparison.Initially,based on the operating principle and maximum thrust force,the surface-mounted magnetic screw is described and optimized.Furthermore,the embedded magnetic screw,Halbach array magnetic screw,and field modulated magnetic screw are investigated and compared.Their electromagnetic performances,such as thrust force,torque,magnetic losses,and demagnetization effects are analytically assessed and verified using finite-element analysis.Finally,a prototype of the surface-mounted magnetic screw is developed to validate the predictions.展开更多
为改善永磁丝杠复杂的螺旋形磁极加工制造难度,对螺旋磁极结构进行改进替代。应用有限元法(Finite Element Method,FEM)对推力和转矩静特性进行仿真,证明丝杠磁极为斜环、螺母磁极为螺旋结构和丝杠磁极为螺旋结构、螺母磁极为斜环的两...为改善永磁丝杠复杂的螺旋形磁极加工制造难度,对螺旋磁极结构进行改进替代。应用有限元法(Finite Element Method,FEM)对推力和转矩静特性进行仿真,证明丝杠磁极为斜环、螺母磁极为螺旋结构和丝杠磁极为螺旋结构、螺母磁极为斜环的两种永磁丝杠结构能够实现平稳传动。由于结构中仍部分存在螺旋结构,故进行实用化改进。方案一是将直环离散的若干圆弧形磁极块阶梯式组合排列;方案二是采用半斜环磁极组合结构。结果表明,后者组合磁极块数更少,在保证运动系统平稳传动的同时,具有更大的推力和转矩。同双螺旋永磁丝杠相比,推力误差和转矩误差仅分别为3.981%和0.583%,故而为替代螺旋磁极的一种较为理想的方案。此外,提出了极距比K的概念,得出K=0.3时,单位磁极产生的电磁推力和转矩最大,磁极利用率最高。在此基础上,将半斜环磁极结构采用Halbach阵列优化,峰值推力和转矩可分别提升42.3%和36.3%,且存在最优辅配比λ=0.4。展开更多
基金Supported by National Natural Science Foundation of China(51977099,51777090)Key Research and Development Program of Jiangsu Province(BE2018107)Six Talent Peaks Project of Jiangsu Province(2017-KTHY-011).
文摘In this study,several types of linear actuators that adopt different permanent-magnet(PM)topologies are studied and compared.These linear actuators are based on the concept of PM magnetic screw transmission,which offers high force density,high reliability,and overload protection.Using different magnetic configurations and assembly methods,these linear actuators are designed and optimized for a fair comparison.Initially,based on the operating principle and maximum thrust force,the surface-mounted magnetic screw is described and optimized.Furthermore,the embedded magnetic screw,Halbach array magnetic screw,and field modulated magnetic screw are investigated and compared.Their electromagnetic performances,such as thrust force,torque,magnetic losses,and demagnetization effects are analytically assessed and verified using finite-element analysis.Finally,a prototype of the surface-mounted magnetic screw is developed to validate the predictions.
文摘为改善永磁丝杠复杂的螺旋形磁极加工制造难度,对螺旋磁极结构进行改进替代。应用有限元法(Finite Element Method,FEM)对推力和转矩静特性进行仿真,证明丝杠磁极为斜环、螺母磁极为螺旋结构和丝杠磁极为螺旋结构、螺母磁极为斜环的两种永磁丝杠结构能够实现平稳传动。由于结构中仍部分存在螺旋结构,故进行实用化改进。方案一是将直环离散的若干圆弧形磁极块阶梯式组合排列;方案二是采用半斜环磁极组合结构。结果表明,后者组合磁极块数更少,在保证运动系统平稳传动的同时,具有更大的推力和转矩。同双螺旋永磁丝杠相比,推力误差和转矩误差仅分别为3.981%和0.583%,故而为替代螺旋磁极的一种较为理想的方案。此外,提出了极距比K的概念,得出K=0.3时,单位磁极产生的电磁推力和转矩最大,磁极利用率最高。在此基础上,将半斜环磁极结构采用Halbach阵列优化,峰值推力和转矩可分别提升42.3%和36.3%,且存在最优辅配比λ=0.4。
