252 Ë 7 Numerical simulations of HTS Maglev
Fig. 7.21:Chart of the Maglev system with three HTSCs undergoing the vertical or transverse
movement above the PMG.
and two PMs magnetized in the horizontal direction. These two PMGs, like those in
Fig. 7.8, derived from the Halbach array, are presented in Fig. 7.20.
In the calculation, we ignore the possible interaction among the HTSCs for
simplicity, and calculate only two HTSCs because of the symmetry of the levitation
system shown in Fig. 7.21. In the default case, the HTSCs are field-cooled at a position
of 30 mm above the surface of the PMG for the calculation of the levitation forces and
the guidance forces, the transverse movement occurs at the same height as the FC
position, that is, 12 mm above the surface of the PMG. The main parameters that should
be optimized in the two structures, i.e. Rail_A and Rail_B shown in Fig. 7.20, are the
ratio between the width of two different magnetized PMs and the width and height
of the PMG. The following section shows the computed results of the optimization by
altering those parameters.
In this part, the levitation forces and guidance forces on the HTSCs with the varia-
tion of the width ratio, i.e.wA1/wA2for Rail_A orwB1/wB2for Rail_B, are calculated. In
this calculation, the total width and height of both PMGs are assumed to be 130 and
30 mm, respectively, and invariant with the change of the width ratio. For simplicity
in drawing the following figures, the width ratio is replaced by an order and the
corresponding relationship between the width ratio and the order is given in Tab. 7.5.
Tab. 7.5:Corresponding relationship between the width ratio and the order in optimizing the width
ratio of the PMGs.
Order 1 2 3 4 5 6 7 8 9 10 11
12 13 14 15 16 17 18 19 20 21 –
Width 0 0.01 0.1 0.16667 0.25 0.333333 0.4 0.5 0.66667 0.83 1
ratio1.22 1.5 2 2.5 3 4 6 10 100 ∞ –