ES Motor Project?

[Miles]

I think the clou is to have the bits next to the magnets very thin so they are oversaturated...

Yes, I guess that's it.

 

[Thud]

The Chevy volt rotor is setup very similar to that, but the magnet bars are in pairs tipped at about 45deg angles to the face.

Thats interesting & a point I hadn't considerd....I assume its to direct flux into a finer point...or at least focus it maybe.

The Jobys seem to have magnet pr faces flat also as opposed to letting them follow the curve of the rotor......more food for thought....need a tub of ferro fluid to see whats up on these configurations....(& it would just be cool to play with )

 

[bzhwindtalker]

Sorry to chime in, but what's the Rpm limit of a hub motor when used as a mid drive? My motor stator is 200x32mm with 0,5mm lams for example. I am looking at running one at 1000-1500rpm.

EDit:
Comutation rpm will be the real limit maybe? Or it is iron losses?

 

[Miles]

Sorry to chime in, but what's the Rpm limit of a hub motor when used as a mid drive? My motor stator is 200x32mm with 0,5mm lams for example. I am looking at running one at 1000-1500rpm.

How many magnets does it have?

 

[toolman2]

Sorry to chime in, but what's the Rpm limit of a hub motor when used as a mid drive? My motor stator is 200x32mm with 0,5mm lams for example. I am looking at running one at 1000-1500rpm.

EDit:
Comutation rpm will be the real limit maybe? Or it is iron losses?

1000-1500rpm would be ok, you will need many volts, ive tested a pie (the least suitable hub for big revs) to 1500rpm and graphed the rpm losses, ill find this, but this is around the revs you really do want to be at, it will be able to make 3 times the power and have way better efficiency than in a 26" wheel, suddenly everything works better, with rpm and ir losses (for once with a hub) will get back into good balance, but because of your massive power increase from this, you start to wonder about a lighter motor to do the job, like say the ones we are looking at here.. :wink:

 

[acuteaero]

Just a note on the captured magnets- the prius MGs use the angled design as mentioned by LFP-

Here is a photo from the ORNL report on the Prius motor- showing the profile of the stampings used in the rotor, with the cutouts that the magnets fit into.



The ORNL reports on the prius motor/powertrain design are pretty awesome- +1 for public-reported government sponsored research- see them here: http://www.ornl.gov/~webworks/cppr/y2001/rpt/121813.pdf and here http://www.ornl.gov/~webworks/cppr/y2001/rpt/120761.pdf. There are other reports too- search for them...

 

[johnrobholmes]

Ive been playing around with motor designs lately, mostly on the smaller scale until I think of something useful on the bike scale.


Outrunning brushed motor anyone? Conceptually feasible, I would love to prototype this one day just to see it work. 18s 6p with off the shelf laminations. Face loading round brushes with inline springs inside those copper tubes.

I've been wanting to design something larger, but just can't get motivated with some specs to start from. Maybe a high pole pancake motor to fit inside a frame and drive the cranks or something.

 

[Miles]

18s 6p

How are you intending to wind it?

 

[johnrobholmes]

Each coil goes around three teeth. I can either have 9 commutator segments and have each coil have its own slot, or have 18 segments and have each coil share a slot with the third coil down. Essentially the difference between advancing one slot or advancing two between coils.


Whats cool is that I could use 2, 4, or 6 brushes for three different motor speeds. All coils in series, to all coils in parallel. At least I think it is cool. :lol:

 

[salty9]

Chevy spark motor

https://www.youtube.com/watch?v=zCo3QUeQ8fA&feature=endscreen

 

[Thud]

Did the details up for the 5" outrunner witha 50mm stator stack.
a tiny screenshot...
I am sending sample to the laser etching place to see if the machine will perform on .008"t steel...its getting interesting 8)