Characteristics in Single-Sided Linear Induction Motors with Asymmetric Composite Secondary

Since the single-sided linear induction motors (SLIMs) for rail transit usually works with an asymmetric composite secondary, the spatial position of the secondary is a key variable for the electromagnetism and force characteristics in the motors. Therefore, this paper investigates the influences of the secondary width and displacement distance on the characteristics, e.g., magnetic flux, and induced eddy current, by using the finite element method. First, an analysis model used for finite element method is given. Second, it defines several coefficients to quantitatively analyze variations in the distortion and average amplitude of the magnetic flux and induced eddy current under different secondary dimensions. Finally, it can be concluded from the analysis of the magnetic and eddy current fields that different sizes of the secondary dimensions present different sensitivities at different degrees of asymmetry.