6.18 Guidance forces of the entire HTS Maglev vehicle Ë 203Fig. 6.68:The vehicle “Century” on the First Science
and Technology Festival of Chengdu in 2005.6.18 Guidance forces of the entire HTS Maglev vehicle [60, 61]
Both guidance and levitation forces are very important parameters for the HTS Maglev
vehicle. The levitation forces between HTS bulks and PMGs are directly proportional
to the gradient of the magnetic field over PMG. The guidance forces provide the lateral
stability of the Maglev vehicle. Both levitation and guidance forces depend on the flux
pinning capability of HTS bulks.
The lateral guidance forces are dependent on the trapped flux in the HTS bulks
and the applied magnetic fields. This Maglev vehicle with bulk HTS does not need any
lateral stability control system, which makes it competitive compared with all other
conventional Maglev vehicle systems. The guidance forces are large and sufficient in
guiding the vehicle while large levitation forces are also achieved.
The guidance forces of the entire HTS Maglev vehicle are not only different from
those in Section 6.7.1, but also not the same as those in Section 6.7.2. The guidance
forces of HTS bulks over a single PMG are discussed in Section 6.7.1. Although Section
6.7.2 describes the guidance forces of HTS bulks over parallel two PMG, it is not the
guidance forces of the entire vehicle. The guidance forces are also measured at forces
sensor on both sides of the suspension carrier. The guidance forces of the entire
vehicle at two parallel force sensors are measured at a force sensor on one side of
the vehicle.
The measuring equipment of the guidance forces of the entire HTS Maglev vehicle
is shown in Fig. 11. The set-up included two horizontal propulsion systems and two
sets of force sensors which were fixed on the vehicle. Each set of the propulsion
system could move in both the horizontal and vertical directions so that they could
measure the guidance forces of the entire vehicle at different levitation gaps. A chain
with a synchronization precision of 0.5 mm connected two sets of propulsion systems.
The moving range of the propulsion system along the horizontal direction was 0 to
20 cm and the moving precision is 1 mm, and the range along the vertical direction
was 0 to 10 cm with vertical moving precision of 1 mm. A photograph of the measuring
equipment of guidance forces is shown in Fig. 5.12. In order to ensure the accuracy
of the guidance force measurements at different levitations of the vehicle, we ordered
eight pull and push force sensors with measuring ranges of 200, 500, 700, and 1000 kg
of±15% accuracy. In order to test the feasibility of the guidance force measurement