The improvement of the performance of PM materials  and the present of Halbach array  greatly promote the application of PM in LSM.
Hoburg analyzed the static magnetic field of dual Halbach array for GA maglev vehicle by magnetization charge theory, but the results are quite complicated .
Thus the LSM has the characteristics of zero power supply on the vehicle because of PM Halbach array and zero normal force because of ironless coil on the guideway.
As shown in , the peak magnetic field at the surface of Halbach array [B.
with [lambda] being the wavelength of the Halbach array.
z] is the attractive force generated by Halbach array and the iron sleepers.
First, the closed-form of the attractive force is deduced from the expression of the magnetic field of Halbach array.
Structure of linear PM Halbach array for EDS Maglev, in the 20th International Conference on Magnetically Levitated Systems and Linear Drives, Part: Vehicles and Levitation Guidance, 7-12.