I want to learn about electrical wheels, typically used in electric bicycles. But most of information I could find is related to marketing, and nothing on theory. This is probably due to "relative novelty of this field", and each manufacturer want to keep its secret. But to become one - one should learn motor construction theory at first.
Afaik, design of the vast majority of these wheels implies multiple coils on the inner stator, which (when fed by AC of rectangular form) forms magnetic fields, that pushes neodym magnets on the rotor, thus creating motion:
But also I heard about (magnetless) squirrel cage rotor, with construction principle, illustrated by following image. Despite it is not a actual motor rotor, it has some similarities in its construction (bars, short circuiting rings) :
Image from: pnpntransistor.com
So I have a question - why even bother with rare and expensive neodym magnets (that could easily break on the road), while always can use latter variant? I dont understand well, how latter works, so it would be nice, if you could compare and explain operating modes of these two types of motors, "side by side" (to show difficulty or impossibility of creating latter variant). Thanks.