The Speed Secrets of Maglev Trains: Equations and Resources

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The discussion focuses on understanding the speed control of Maglev trains using Linear Synchronous Motors (LSM), emphasizing that speed is adjusted by varying the frequency of the supplied power. The mechanics involve magnets on the train cars and electromagnets on the track, where alternating polarities create movement through magnetic repulsion and attraction. The conversation also touches on the complexity of designing circuits for the hover function, which requires managing the diminishing magnetic field strength with distance. Additionally, a different Maglev design using permanent magnets and induced electromagnetism is mentioned, highlighting an alternative approach to maintaining train stability. Overall, the thread seeks to deepen understanding of Maglev systems through equations and resources.
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I've been studying Maglev system.This concept is quite new to me, so I need your help for followings:
From my understanding the speed of MagLev Train applying Linear Synchronous Motor (LSM) is only controlled by varying the Frequency of supplied power, So could you show me the related equations?

I want to get the more comprehensive understandings of MagLev System, so I prefer you to provide me some related documents!

Thank you!
 
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Lets oversimplify the maglev to make it simple to talk about, to do so picture a regular wheeled setup at first.

On the bottom of the train cars are magnets that alternate north-south-north-south.

On the track there are electromagnets that alternate south-north-south-north.

The electromagnets are switched so they have the opposite pole, now the likes repel and opposites attract thus the train moves. Change the frequency the switching happens at and the speed could change as well if within reason.

Easier would be examining how a DC motor works. Same concept except it is setup to spin and the brushes switch the electromagnets mechanically. But like the maglev you could use permanent magnets on the shaft and switch coils around the shaft to spin the magnets.

Now, the maglev is quite complicated in terms of designing circuits to control the 'hover' aspect of it. Now you need to harness the power of a magnetic field that decreases exponentially with distance and create forward motion and keep the cars on a track.

There were some posts a while back about building a maglev and in the discussion a different type of maglev was linked to that used permanent magnets on the train cars and coils for the track. The difference was that the coils were not powered but instead used the current induced from the moving magnets to turn them into electromagnets, and that the track was shaped to keep the train cars centered.

Once you've mastered building your own segway type machine that balances on 2 wheels the maglev would be the next step up in difficulty.

Cliff
 
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