The TFM1 model uses separate stator sections for each phase. Each section is identical and are mounted side by side on the shaft. The image show one section only which enables a single phase.
The route for the magnetic flux requires 3-D modelling. Flux concentration is used at the poles.
The flux at each stator pole is generated by two magnets mounted on the rotor with same polarity facing each other with an iron core in between. All the magnets will therefore repel the closest neighbouring magnets.
On the rotor side the magnetic flux will move from one side of the iron core to the other depending on which side the stator pole is closest. This concentrates the flux on alternating opposite sides before crossing the small air gap between the stator and rotor poles. The magnetic flux is reversed in the stator when the rotor spin and the stator poles change position one step compared to the rotor magnet poles.
The rotor spins outside the stator. This “outrunner” configuration enables shortest possible copper windings.
The air gap between the rotor and stator is smallest possible to enable stronges possible magnetix flux using moderately sized magnets.
The magnets can optionally be shared between the phases on the rotor side by extending the length so that they cover the 3 sections required for a full 3-phase.
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