6.12 Maglev of HTS bulk above magnets Ë 183levitation phenomenon was discovered in 1988, the idea of the Maglev train using a
HTS bulk Maglev was considered. In 1987, the breakthrough in HTS material was follo-
wed by the rapid development in China, which has greatly strengthened and promoted
the original ideas about HTS Maglev. In 1992, Jia-Su Wang and Su-Yu Wang started to
read the relevant literature, electromagnetic suspension, electrodynamic suspension,
normal conductive Maglev, superconducting Maglev, highTcsuperconductivity etc.,
and then gradually formed some tentative plans.
In 1994, the president of Southwest Jiaotong University, Xiang Sun, approved the
report on the superconducting Maglev submitted by Jia-Su Wang and Su-Yu Wang. In
1996, Jia-Su Wang and Su-Yu Wang discussed the problems about the manned HTS
Maglev vehicle with Prof. Hong-Tao Ren of GRINM (General Research Institute for
Nonferrous Metals) in the Dalian Conference of Information Net of Cryogenics and
Superconductivity. At first, Ren believed that the project was too risky, but finally
accepted this high-risk project. Continued technical progress steps for the HTS Maglev
had been achieved through the efforts of the experts, which included improvement
of the HTS bulk performance, suspension of a sumo wrestler in Japan, successful
demonstration of a HTS Maglev model on a small orbit during the 100th anniversary of
Southwest Jiaotong University), and the Maglev demonstration model using a linear
motor achieved through Chinese and German cooperation. These vigorously promoted
the manned HTS Maglev vehicle development process.
In the early days, the superconducting Maglev vehicle only referred to LTS magne-
tic levitation [44]. The concept of a HTS Maglev vehicle [45] was gradually formed in
the 1990s. Jia-Su Wang and Su-Yu Wang [45–48] have presented several Maglev vehicle
schemes using HTS YBCO bulks in the 1990’s. First, the YBCO bulk superconductors
were arranged above the guideway using NdFeB PMs. The second scheme was the
electromagnetic suspension (EMS) Maglev vehicle using HTS PM or HTS wire. The
third was the EMS Maglev using HTS PM.
6.12 Maglev of HTS bulk above magnets
At first, we considered several HTS Maglev versions of HTSCs over an applied magnetic
field using PM or electromagnets [45, 48]. In Fig. 6.39a, [45] PM poles are arranged
alternately, and in Fig. 6.39b, the iron between both opposite PM poles produces
a concentrated magnetic field. The latter has higher magnetic flux density, and it
can attain a greater magnetic levitation force. Figure 6.39c shows the electromagnet
guideway.
There is a large levitation force between two normal PMs, but this levitation
force is unstable. The HTS bulks in the condition of field cooling (FC) have a high
stability. It perhaps is a valid scheme to combine the large levitation forces between
both normal PMs and the high stability of HTS bulk superconductors. Combining