Miles' DIY motor thread
- Thread starter Miles
- Start date
HAL9000v2.0
10 kW
Maybe I am wrong?!!? If the controller is full sine there should be in both ways, right? If it is PWM then they are just in one way?
Now I am not sure....
Now I am not sure....
j3tch1u
10 kW
Miles said:
no idea on where to get them. you might want to try a to ensure the machining process doesn't compromise the electrical insulation of the "slices". my concern is that if you chop thru a cross section of laminated iron, you will cause some shorts or at the very least lower the resistance considerably (which defeats the purpose of using lams altogether). a lot of deburring, cleaning/re-varnishing of the edges may be necessary. might be worthwhile before you plunk down a chunk of change and hunk of hard work :wink:
j3tch1u
10 kW
Miles said:What's the force in the other direction? I wish there was oneHAL9000v2.0 said:
i believe there indeed would be lateral force between rotor and stator (and thus on the inner and outer bearing races). if i'm not mistaken, i read that the rotor must be very stiff and twin-rotors are sometimes used to balance out the forces. a nice angular bearing or thrust/radial combo perhaps?
j3tch1u said:
I assumed that the (axial) attraction between the magnets and the core would predominate, that's why I used a 40 deg. angular contact bearing at the back end and a radial bearing at the pulley end. I still think this is adequate, but I'll check it out
PS The radial bearing is a proper motor bearing, not one of those thin section jobs
mwkeefer
1 MW
Miles said:I found this today: http://alexandria.tue.nl/extra2/200111643.pdf
Wow - to think I was prepared to read an entire 3 page article or somthing, that thing is more the size of the bible... good find!
-Mike
HAL9000,
You are correct, the turbine in the image would move way too much air and cause excessive loss. It was just something I had laying around in my CAD collection to do a quick photochop with. Good eye though
Miles,
Neat paper, with some of the answers to the questions here, like the magnetic force of the rotor being attracted to the stator. Thanks for sharing your find.
You are correct, the turbine in the image would move way too much air and cause excessive loss. It was just something I had laying around in my CAD collection to do a quick photochop with. Good eye though
Miles,
Neat paper, with some of the answers to the questions here, like the magnetic force of the rotor being attracted to the stator. Thanks for sharing your find.
j3tch1u
10 kW
Miles said:j3tch1u said:
I assumed that the (axial) attraction between the magnets and the core would predominate, that's why I used a 40 deg. angular contact bearing at the back end and a radial bearing at the pulley end. I still think this is adequate, but I'll check it out
PS The radial bearing is a proper motor bearing, not one of those thin section jobs
ahh, i didn't read that part--thought they were both radial. looking good miles. an impeller fan right inside the stator would be really cool. what software are you using? maybe you can do a motion/air-flow sim.
Microbatman
1 kW
Miles said:I found this today: http://alexandria.tue.nl/extra2/200111643.pdf
Nice find!!! Thanks for posting the link to this.
Microbatman
1 kW
Miles and others
Here is some additional info I found about Axial Flux motors.
http://www.osti.gov/bridge/purl.cover.jsp;jsessionid=0BC595DADCB214160760AE354CD8A011?purl=/32793-EurpZA/webviewable/
Click on the 5mg file.
This magnet arrangment/geomertry is a big deal!!!
In a nut shell it ELIMINATES the need for
1 Using laminated steel/iron (see page 5 of document)
2 A flux containing device like a flux ring
The other advantage to this design is that it also concentrates and focuses the flux for more power.
This translates into more efficient power less weight. Who could ask for more?
Disadvantages could be cost/labor that come from the need to arrange alot more magnets. But this may be offset with the savings from not needing laminated motor steel.
Here is some additional info I found about Axial Flux motors.
http://www.osti.gov/bridge/purl.cover.jsp;jsessionid=0BC595DADCB214160760AE354CD8A011?purl=/32793-EurpZA/webviewable/
Click on the 5mg file.
This magnet arrangment/geomertry is a big deal!!!
In a nut shell it ELIMINATES the need for
1 Using laminated steel/iron (see page 5 of document)
2 A flux containing device like a flux ring
The other advantage to this design is that it also concentrates and focuses the flux for more power.
This translates into more efficient power less weight. Who could ask for more?
Disadvantages could be cost/labor that come from the need to arrange alot more magnets. But this may be offset with the savings from not needing laminated motor steel.
Thanks for posting that, Micro. Useful info, there.
We discussed Halbach magnet configurations a bit in some of the older threads.
I decided to go for a conventional arrangement with my first motor. The custom magnets for an effective Halbach array would be quite expensive, for a one-off, I think....
Enoob experimented with a Halbach array using cylindrical magnets with radial poles: http://www.endless-sphere.com/forums/viewtopic.php?f=30&t=14264&start=0
We discussed Halbach magnet configurations a bit in some of the older threads.
I decided to go for a conventional arrangement with my first motor. The custom magnets for an effective Halbach array would be quite expensive, for a one-off, I think....
Enoob experimented with a Halbach array using cylindrical magnets with radial poles: http://www.endless-sphere.com/forums/viewtopic.php?f=30&t=14264&start=0
The latest.....
I've decided to try an SMC core, for the first prototype. There will be a bit of a performance hit but making the core will be a breeze.... Hoganas produce prototyping blanks and one of the available sizes is 80mm dia. 20mm thick. I've increased the motor case diameter from 80mm to 90mm (3.5", actually..) to take full advantage of this.
Having 3D flux means it's possible to have a lip on the periphery of the core, to take the area of the gap out over the end-turns and to max. radius.. It also means that it makes sense to revert to a parallel slot for the windings...
I've decided to try an SMC core, for the first prototype. There will be a bit of a performance hit but making the core will be a breeze.... Hoganas produce prototyping blanks and one of the available sizes is 80mm dia. 20mm thick. I've increased the motor case diameter from 80mm to 90mm (3.5", actually..) to take full advantage of this.
Having 3D flux means it's possible to have a lip on the periphery of the core, to take the area of the gap out over the end-turns and to max. radius.. It also means that it makes sense to revert to a parallel slot for the windings...
