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Tiny electric motor can produce more than 1,000 horsepower

supercarblondie.com

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Re: Tiny electric motor can produce more than 1,000 horsepower

#31

Post by jansan »

dinkblam wrote: post #13
davedx wrote: post #6

Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. YASA was founded in 2009, a spin out from Oxford University following the PhD of founder and still CTO, Dr Tim Woolmer. "Over the decades that followed both of these technologies were explored. But despite the potential for weight reduction, smaller…

saving 30 kg of weight on a 2000 - 2500 kg car won't lead to "significant efficiency gains"

Weight reductions on an electric car are self-reinforcing. If you reduce the weight of a component, the battery can become (slightly) smaller, which again reduces weight. At a certain amount of reduction this will allow you to make the whole structure lighter, which will again allow for a smaller battery.

So yeah, weight reduction on EVs is great.

Re: Tiny electric motor can produce more than 1,000 horsepower

#32

Post by nmehner »

Kaibeezy wrote: post #28
nmehner wrote: post #15

Earlier quoted context omitted.

The issue with this type of motor is that it is part of the unsprung weight since it is inside the wheel. This is probably why savings here matter a lot more (or at least in a very different way) than the battery weight.

See also the Saab Emily GT project. Even with an older, heavier gen of these axial flux motors they found significant performance gains by controlling each wheel via its own motor. https://electrek.co/2023/04/27/saab-engineers-develop-secret...

I didn't want to put the usability of the motor into question or go into a complete evaluation of advantages/disadvantages :) This was just an explanation that weight trimming the motor might be very much worth the effort - even if it somewhat "insignificant" compared with savings that are possible in battery weight.

Re: Tiny electric motor can produce more than 1,000 horsepower

#33

Post by defrost »

agys wrote: post #18

Everything but the Metric System: “The new YASA axial flux motor weighs just 28 pounds, or about the same as a small dog.” :)

The link you're quoting, the one posted, is a second hand US report.

The primary company link is from a UK subsidiary of Mercedes-Benz and is (almost) fully metric (the fundemental units US weights are officially defined with respect to (for more than a century now)).

See: https://yasa.com/news/yasa-smashes-own-unofficial-power-dens...

  Earlier in the summer YASA achieved 550kW (738bhp) from a 13.1kg version of its new axial flux prototype motor, equating to an unofficial power density world record of 42kW/kg

  Now latest testing of an even lighter 12.7kg version on a more powerful dynamometer has shattered this record, with a staggering 750kW (>1000bhp) short-term peak rating, resulting in a new unofficial power density record of 59kW/kg
Just those pesky trad bhp units left hanging like a chad in a Florida election . . .

Re: Tiny electric motor can produce more than 1,000 horsepower

#35

Post by b112 »

poniko wrote: post #9
amelius wrote: post #7

Earlier quoted context omitted.

But EVs are already heavy because of the battery. I suppose percentage-wise the motors don't make much of a difference (?)

Yea that's the thing right, the battery is so very much of the weight that optimizing the other parts are "meh" at this point. What is cool is that the 600Wh/kg solid state batteries seems like they are really finally here soon :) i.e removing 200-300kg from a car in one go will be a game changer.

No wonder electrics don't sell well in the US. People weigh more, you're basically saying that leaving grandma at home, is a "game changer".

Re: Tiny electric motor can produce more than 1,000 horsepower

#36

Post by close04 »

nmehner wrote: post #15
amelius wrote: post #7

Earlier quoted context omitted.

But EVs are already heavy because of the battery. I suppose percentage-wise the motors don't make much of a difference (?)

The issue with this type of motor is that it is part of the unsprung weight since it is inside the wheel. This is probably why savings here matter a lot more (or at least in a very different way) than the battery weight.

YASA doesn't call it a hub motor specifically but that's one place where it helps to save as much weight as possible. And for the cars most likely to have 1000+HP weight matters too. A Tesla motor weighs 100-200lbs, so saving that much weight down to 28lbs on a supercar is highly desirable.

I think large drones will be another place where a downsized version of this motor will make a huge difference, assuming the power scales nicely with size.

Re: Tiny electric motor can produce more than 1,000 horsepower

#37

Post by rob74 »

nmehner wrote: post #15
amelius wrote: post #7

Earlier quoted context omitted.

But EVs are already heavy because of the battery. I suppose percentage-wise the motors don't make much of a difference (?)

The issue with this type of motor is that it is part of the unsprung weight since it is inside the wheel. This is probably why savings here matter a lot more (or at least in a very different way) than the battery weight.

Ok, now I understand why this motor is only used in supercars - installing four (or even only two - according to https://www.mercedes-benz.de/passengercars/technology/concep..., even the AMG GT-XX has "only" three of them) hub motors with twice the power of a Tesla Model 3 in any other car would be ridiculous. So, the actual challenge is to make this motor even smaller while keeping the same power to weight ratio, so it can also be used for regular cars? That is, if they want to build something for the mass market, not only for an exclusive clientele?

Re: Tiny electric motor can produce more than 1,000 horsepower

#40

Post by otikik »

dinkblam wrote: post #13
davedx wrote: post #6

Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. YASA was founded in 2009, a spin out from Oxford University following the PhD of founder and still CTO, Dr Tim Woolmer. "Over the decades that followed both of these technologies were explored. But despite the potential for weight reduction, smaller…

saving 30 kg of weight on a 2000 - 2500 kg car won't lead to "significant efficiency gains"

If you put several small motors on each wheel you might get some extra weight gains in the form of less transmission needed. Cables weight less than metal structural bars. But yes you are not going to be 500kg lighter.
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