基于有限元的永磁导轨磁场数值计算

Numerical investigation of magnetic field of a permanent magnetic guideway based on finite element method

文中采用有限元方法计算了永磁导轨的磁场分布,永磁导轨由NdFeB、铁构成。讨论了截断边界和开尔文变换边界对计算结果的影响。计算结果表明,采用开尔文变换边界的计算结果更接近实际情况,而且可以使求解区域大大减小,从而提高计算精度和准确性。为了验证计算结果的可靠性和准确性,根据模拟计算参数,制作了一条1∶1的永磁导轨,导轨中心表面磁场达1 20T。测量结果表明,计算结果与永磁导轨磁场的实测值吻合较好。

Magnetic field of a permanent magnetic guideway composed of NdFeB and iron is investigated numerically based on finite element method. Taking infinite solution region of the guideway into account, the influence of two different boundaries (truncation method and Kelvin transformation method) on computational results is discussed. Numerical results show that Kelvin transformation method is better than truncation one. Moreover, Kelvin transformation method can shrink the resolution region and improve precision. In order to validate the reliability of numerically computational results, a permanent magnetic guideway was built at 1∶1 scale according to relative parameters used in numerical calculation. The magnetic field is measured over the guideway, and the surface concentrating magnetic field is up to 120 T at the center of the guideway. The measuring results of magnetic field of the guideway agree well with the computational ones.