The metal coils that line the track become a magnet once
electric current flows through the coils. This repels the
guidance magnets on the train, which causes the train to
levitate 1 to 10 cm above the electromagnetic track.
An illustration shows how the guideway works.
Once the train is levitated, electric current flows
to the coils within the track to create another system of
magnetic fields that propels the train along the track. The
concept behind this is the motor principle, where force is
generated from the cross product of the electric current
and magnetic field vectors. The magnetic coils are generated
by an alternating current that changes the polarity of the
magnetized coils, which causes the magnetic field in front
of the train to pull the vehicle forward, while the magnetic
field behind the train pushes the train along. Because the
train is levitatd,
friction
betweene
the train and the track is non-existent, decreasing mechanical
strain and increasing
top speed potential.
Magnetic field in front of the train pulls the vehicle forward, while the magnetic
field behind the train pushes the train along.
Currently, the two main sponsors of MagLev technology
are Germany and Japan. The United States is reconsidering
the option to develop MagLev trains while China is planning
to install MagLev lines that will connect its major cities
as well as between airports and city centres.
Credits:
1. Bonsor, Kevin. How
Maglev Trains Work. How Stuff Works, Inc. <http://travel.howstuffworks.com/maglev-train.htm/printable>
2. Railway Technical Research Institute.
<http://www.rtri.or.jp/rd/maglev/html/english/maglev_frame_E.html>