Halbach Axial Flux Motor

AussieJester... since you are always bragging about "actually riding" being the most important thing, just how many miles have you ridden?

I mean if I've gone 7,120 miles doesn't that grant me the right to dream a little? If all I did was talk I can see you complaining, but I'm probably doing 5 times the miles you are... if comparing miles is so important that is. :whistle:

WTF...When have i EVER "bragged" about riding and electric bike Safe quote me please?? ? YOU SiR are the twat that continually feels the need to tell eveyone how many miles you have ridden NOT ME..

I rode my trike daily I have no idea nor do i care how many miles i rode why should I?? Guaranteed i have done many many more miles than you around a race track though safe how many have you done? Hrmmmz? I raced for years pal you have NEVER stepped foot on a race track other than too watch others but continually express you know all about road racing when in fact you know very little.

I have nothing against you "dreaming" as you put it but fark me you could at least keep it within the realms of YOUR possibilities. I encourage you to continue I enjoy watching you fail...

KiM
 
Anyone here interested in getting back to the original Topic "Halbach Axial Flux Motor" ????????????????????????????????????????????????????

Sorry, AussieJester likes to knock me down as much as possible, it's hard not to want to knock him back.

luka69, I just downloaded the zip file you linked to and I looked at one of the pdf. Excellent! You earn Five Golden Stars because not only do they build Halbach motors, but they show all the math.

Give me some time reading it... thank you very much!!!
 
I raced for years pal you have NEVER stepped foot on a race track

I never raced road racing, but for BMX, Mountain Bikes and Motorcycle Motorcross I raced. I trophied every race... (or crashed) not always first, but in the top four if I made it to the finish. At the time when I went to college I just couldn't afford to road race, so it sort of got pushed back in priority. (life is like that)

Don't worry... I was never one of those "dorks" that had no rider skill and a fast bike. I've always been fast on the bikes. :cool:

Any more "ragging" on this thread and I hit the "report" button !!!

I encourage you to continue I enjoy watching you fail...

Says the disabled person with bad legs. Geez... you always figure that people with serious injuries become somehow better human beings, but it didn't seem to work with you. Just cut it out... seriously.
 
Last edited:
Instead of fiberglass why dont you try carbon fiber as it is shown in one of the exploded drawings, you could layer this over thinner aluminium for the same strenght making for a slimmer motor? would also be a **** site strong than fiberglass ...downside you would need to make a simply vacuum chamber too place the layered up carbon fiber in ..althoooough, looking at the motors design everything is flat plate that would need to be made using carbon fiber so would it be possible to simply weight down the layed up job between two plates with release agent on them, when dry pry them apart?

KiM
 
I accept your reasonable tone... :cool:

Carbon fiber is a good idea. Aluminum is light too and since you can buy chainrings pretty easily that makes it a little easier.

The trick I think is going to be the way that you either do bearings or not. One of the advantages of using the rear wheel is that it already has bearings. You sort of solve the bearing problem for free.

There are different ways to position the coils in relation to the disc.

One design is to have magnets on one disc and a second disc in parallel.

Another design places the stator side on the outside (outrunner? inrunner?) and that would make it thinner.

------------------------------

What's interesting is the idea of front and rear disc brakes where the magnets are built into the design. You could even do better regen with the front.

There are a lot of ways to approach this...

1.4 lbs for 7 hp is just insane. :giggle:
 
Last edited:
You have a woodwork router Safe? if not they are cheap to buy mine was under 40 bucks, you can use these to mill aluminium, a small jig can be made to router the recess for bearings no probs at all, i haven't done this myself (yet) but have seen it successfully done by ES member Grinhill on his first RC MTB build checkit out in the non hub motor section there's pics of his ghetto jig he made, outstanding results too would solve that issue...I dont think the hub idea is a goodun on further thought..not feeling it...prolly coz it has the word "hub" associated with it LoL

EEEEEven though these motors have a nice spread of power you could still benefit from gears i think, i wouldn't totally discount using some form of 'changeable' gearing, not in your application anywayz ...for general commuting OK, but for high performance application it would be a good option to have i think..?? I guess try without see how it goes as its the simple route to go, if it works as planned great if not you can modify later rather than going gear setup and then finding it wasnt needed.. Sounds like your pretty set on direct drive though so be it...

KiM
 
Last edited:
You don't like the hub idea why?

The only negative reasons for the old hub motors were that they had a narrow powerband (which could be fixed with Delta - Wye) and the fact that all that iron makes for a heavy hub.

Also... remember that "legal thing"? The main reason for all this? The idea being that you want to build something that can be prevented from going faster than 20 mph, but that produced a pure 1 hp output and (if given a different controller) could extend it's top speed to either 30 mph or unlimited while maintaining the constant 1 hp.

This Halbach design seems to address every issue that I've had over the years and if you add the multispeed gearing back in then you run into problems with legality.

---------------------------------

AussieJester, you also need to realize that "constant power" means that gearing would NOT make much difference. If the load is increased, then the speed is reduced and the torque increases. The formula becomes:

Constant One Horsepower = Motor Rpm * Motor Torque

...unlike with the regular permanent magnets with their "peaks" these other types come pretty close to maintaining constant horsepower once they get up to a certain speed.

These are in effect "Constant Horsepower Motors".

(which is unlike what we are used to)

Technically speaking you can't allow more than 20 mph in the legal configuration and even in my older way of thinking (sell as one speed, then let them add multispeed) I had to prevent the higher speeds.

Until something comes up that proves the Halbach idea "false" I'm going to continue assuming it's "true".

------------------------------------

This sort of gets back to the "base speed" issue. I'm not sure what defines the "base speed" on the Halbach motors (will need more study) but I think it's going to have to do with the ability of the magnet wires to handle current. My guess is that with enough copper in the stator that you should be able to get some pretty nice low end torque. It probably comes down to the strength of the magnets too... sure to be a formula for that when I find it.
 
Last edited:
Where did you pull up the field weakining idea on the hallbach? They are synchronous motors. The Hallbach array is to concentrate flux without steel flux ring, so it can be built with nonferrous material backing the magnets. The array causes a sin wave on phase output with no steel stator, so efficiencies can be very high with a sine wave drive. The no cogging design is just an effect of axial motors being built iron free....



The Halbach Axial motor is nothing but a PM 3 phase turned on its side with a fancy magnet scheme to concentrate flux. If you want a 12 slot motor you can use 8, 10, 14, or 16 magnets with matching 3 phase winding schemes and proper magnet coverage. 72 magnets with alternating polarity would not work, the magnet width would be too small as compared to the pole width.
 
Back
Top