Field Reconstruction Method for Linear Tubular Permanent Magnet Motor

This paper considers a linear tubular permanent magnet motor (LTPMM) for an active suspension system. The LTPMM has an end effect due to its structure. This can be an important factor for analysis and design of the LTPMM because it distorts the air-gap magnetic flux distribution. The field reconstruction method (FRM) was developed for an effective evaluation of the magnetic field in the electric machine. It can reduce the computation time using the basis-function which reconstructs the air-gap magnetic flux distribution with a static finite element analysis. In this paper, we adopted the FRM to evaluate the LTPMM. However, the FRM has been applied only to the rotating machines and does not take into account the distortion of the magnetic flux distribution in the LTPMM. To deal with this problem, we proposed an enhanced FRM with new basis-function. The proposed method is verified by comparing between experiment result, conventional and enhanced FRM.