Searching for Buddy in promising magnet motor Project.

[dieter]

Thanks again.


Here's an important update:


A flaw surfaced in the last design suggestion.


Let me try to explain: While indeed the C-core on the rotor steals the flux from the stators PM-Coil fluxpath and does force the fieldstrength drop in the coil core, this current flow and its field practically increases and decreases the permeability of the core, resulting in an increased petmeability while approaching and a decreased permeability while moving away. So the flux will stick longer to the stator while the rotor is approaching (and that means it will less azteact the C-core/Rotor), and when moving away the flux will also remain longer on the Rotors C-Core, because the coil core, due to increasing field strength, has a flux-blocking tendency.


So it's a brake, Lenz, out of his grave, still a very difficult person he is ^^


However, I have already a particular solution to this undesired sideeffect. That being said, it's becomeing increasingly difficult to simulate these inteactive and dynamic processes in Femm.


Bottom line, if Inventors would have given up because of frequent failure, we would still be useing torches to light up our caves.

[Thaelin]

That simply is called the thrill of the chase.

[dieter]

Yeah, featuring Burt Reynolds as John Bedini etc. ^^


What seems to be the solution to the problem described above, are two PMs on the rotor, above and below the stators coil core, polarized as a "3way crossroad" that acts due to the dynamic permeability of the core as some kind of magnetic transistor.


So the dropping fieldstrength in the core does no longer lower the attraction of the stator, because the flux will pass trough these two PMs of the rotor. That way the rotor is attracted additionally.

[dieter]

...
I have tested conditions with decreasing fieldstrength (rotor comes closer) and carefully added up all involved attraction strengths. I did the same with increasing fieldstrength (rotor moves away). I achieved a slight gain of like 15% in that attraction during approaching is higher than during departure. This is without useing the current flow.


But Femm really makes it tricky. Results differ, depending on coil core features. According to Femm I should best use a ceramic 5 PM as / instead of the coils iron core... weird but maybe worth trying.

[Low-Q]

Are you using scripts which positions the moving magnet automatically with for example 1mm increments and measure forces for each step?


Vidar