172 Ë 6 First manned HTS Maglev vehicle in the world
On the basis of the experimental research, Wang et al. [35, 36] also completed a
numerical simulation and programmed a calculation of the guidance forces.
6.7.3Guidance forces of multiple seeded melt growth YBCO [27]
The guidance forces of the multiple seeded melt growth (MSMG) YBCO bulk over the
PMG were measured by the HTS Maglev measurement system SCML-01 (see Fig. 5.7).
First, the YBCO bulk was cooled rightly above the center of the PMG and the field
cooling height (FCH) was 20 mm. Then, it moved along thex-axis from a maximum
lateral displacement (+20 mm) and finally returned to the start point of this lateral
movement (similar to Fig. 6.18). The speed was 2 mm/s in the cases of both vertical and
horizontal movement, so the interaction between PMG and MSMG might be regarded
as quasi-static.
The guidance forces of the MSMG bulk and the array of three SMG bulk were
compared in both parallel and perpendicular modes (Figs. 6.25 and 6.26). Their
maximum guidance forces were 70.1 and 69.3 N in the parallel mode, while 56.3 and
56.2 N in the perpendicular mode. The difference between them was 13.8 and 13.1 N in
the two different modes. Although both the placement and movement direction of the
MSMG bulks were extremely different in the parallel and perpendicular modes, their
maximum guidance forces almost did not change. This phenomenon seems to be con-
troversial with the conclusion that the guidance forces are dependent on the trapped
field of the HTS bulk, because the trapped fields in the different modes are significantly
different. In fact, the guidance forces are the total pinning forces determined by both
the trapped field and the applied field during the magnetic interaction process.
6.7.4Influence of two tilted PMG on the guidance forces [37]
In order to measure the lateral guidance forces of HTS Maglev equipment over tilted
PMGs, the Maglev measurement device of tilted PMGs was manufactured (Figs. 6.27
Fig. 6.25:Guidance forces of the MSMG
bulk and the array of three SMG bulk in the
parallel mode [27].