How on earth is this propelled?

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The discussion centers on the propulsion mechanisms of maglev trains, specifically contrasting Electromagnetic Suspension (EMS) and Electrodynamic Suspension (EDS). Participants clarify that EMS uses attraction along a guideway, while EDS employs the alternation of magnetic poles for propulsion. The propulsion system in high-speed maglev trains, such as those in Germany and Japan, utilizes a long-stator linear synchronous motor, likened to an unrolled electric motor. Confusion arises from inconsistent explanations found in various resources, prompting a deeper exploration of the technologies. Overall, understanding these propulsion methods enhances comprehension of maglev train operations.
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how on Earth is this propelled??

the usual system is this:

http://www.rtri.or.jp/rd/maglev/html/english/maglev_frame_E.html

where fields are created in in guideway walls to propell the train...

amazing stuff.

BUT


http://www.bwmaglev.com/technology/default.htm

Its easy to see how attracting magnets can make the train levitate... but how is it propelled??


One is called Electromagnetic Suspension... (EMS) and the other is electrodynamic suspension (EDS).
I THINK that the first example is EDS and the second is EMS... if so, how are EMS systems propelled...?
The HowStuffWorks site is really inconsistant in its explanation and has only served to confuse me more.

does anyone actually get this?
 
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I'm not sure I get the distinction between the two technologies, but is there any reason why they don't both use alternation of poles for propulsion?

It's identical to how an electric motor is set rotating. Take an electric motor and unroll it like it were a sleeping bag and you have a maglev train. The rotor will scoot along the stator.
 
i've got it now it think... been pouring over it for 3 hours solid...

this is how EMS works: http://www.maglevpa.com/tech.html

this is how EDS works: http://www.rtri.or.jp/rd/maglev/html/english/maglev_frame_E.html (look under Principles of MagLev)

fascinating stuff!

one uses the alternation of poles (EDS) and the other uses attraction along a guideway. simple once you've got head round it.
Thanks anyway!
 
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The high-speed maglev systems in Germany and Japan both use the same approach to propulsion: it's called a long-stator linear synchronous motor. DaveC426913 compared it to taking "an electric motor and unroll[ing] it like it were a sleeping bag," and that's a good visual, but there are more technical expanations that are better in the long run.

There's a good discussion of this at www.dot.state.co.us/publications/maglev/inductionmotors.pdf, starting on page 14 (document page 8).
 
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