ＴＩＧＡ　可変界磁モーター　 Variable Field Magnet Motor　　Solar Car - The funniest videos clips are here

So this device is run by a variable field magnetic motor. Does anyone know how these work. You can see in the video how the motor is controlled (by pulling the electro-magnets further from the... whatever it is), but how or why does this process work? Any links to relevant information would be awesome.

(I know I don't have many readers currently, but those who happen to find this, please post a comment directing to any relevant/related information. Thanks!)