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Old 05-16-2018, 08:00 PM
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dyetalon dyetalon is offline
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Join Date: Nov 2007
Posts: 134
Originally Posted by bistander View Post

Beg to differ. Take for example a DCPM motor, PM field stator with wound armature rotor. Like the Imperial from Ufo's Asymmetrical thread. The backiron is the outer steel tube and has a static (unchanging) magnetic field or flux in it. There is zero loss in the backiron. bi
What about path length for the field? There's probably a .15mm gap between one pole and the rotor, but the other pole has to go thru the backiron, bearings, shaft, half the rotor and then to the rotor tip. Doesn't sound very balanced, does it?

Originally Posted by bistander View Post
Similar example. Magnet stuck to refrigerator. Magnetic field (flux) from the magnet completes the path through the steel panel on the fridge. Does the steel panel get hot? Is there power loss in that magnetic circuit (magnet and steel)? bi
Magnets don't generate heat sitting still. I said something to that effect in an earlier post.

Originally Posted by bistander View Post
Most all the typical motors (excluding transverse flux and homopolar) are double air gap machines meaning they do use both a N and S stator pole, both facing the air gap, magnetically connected through the stator by the backiron.


You need to look at one of mine:

It's by no means typical. No magnets in this one. Its a switched reluctance design. when the price of neo's went up I had to come up with a new plan.
Switched the magnets out to Hiperco and reversed the drive logic.

It sucks instead of blows

(as in attraction vs. repulsion)

Last edited by dyetalon; 05-16-2018 at 08:04 PM. Reason: spelling
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