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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

#221

Post by ehnto »

lunias wrote: post #198
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…

I wish more people on the road realized the extent to which weight reduction improves all aspects of the driving experience... it really does compound unlike any other change that you can make to a vehicle. IMO heavy vehicles are a scam and the antithesis of the direction we should be moving.

I agree with you however I believe weight and safety are in a complex relationship right now, which has nothing to do with performance and handling.

Unfortunately I feel much less safe in a Fiat 500 when a significant portion of cars in the road weigh nearly 3 tonnes and perhaps can't even see me. I suspect most people are in SUVs because they're the pragmatic trade off between safety and convenience, not because they were hoping for excellent performance.

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

#222

Post by lazide »

Tostino wrote: post #216
lazide wrote: post #180

Earlier quoted context omitted.

It’s great anywhere you want more power but are limited by space and/or weight for performance reasons. Aerospace, e-bikes, electric race vehicles, electric motorcycles. But yeah, EVs seem weird except for racing reasons perhaps. What I can’t figure out is how they dissipate the heat - double digits kw per kg is crazy.

The first step to dealing with heat at high kw, is to not generate the heat you have to dissipate in the first place. Which means chasing smaller and smaller efficiency gains, because that reduces heat generated. The more of the energy going into moving the vehicle, the less heat the motor has to handle.

Sure, but at 50kw/kg at 99% efficiency is still 500w/kg, which is cray cray. Like ‘glowing red hot shortly’ type of crazy with just passive cooling.

And there is no way this is 99% efficient.

So my question still applies. Even 98% is 1kw/kg, or 1kj/sec. or around 3C rise per second assuming the mass is 100% nice clean copper (it isn’t). Everything else will be worse.

Not even counting increasing losses with temperature, it will be a molten puddle pretty quick at that rate without some major active cooling.

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

#223

Post by jve »

zufallsheld wrote: post #63
mrtksn wrote: post #50

Earlier quoted context omitted.

I wonder if Americans don't have a mental image for measurement units so that they alway use some physical object as a reference. Sure, its useful to use a common object as a reference but I don't see that much often in other places. Most people usually understand what it means something to be 20 meters, 5kg or 2 liters intuitively. Like, when I hear that something is 60m tall I intuitively think if it as 20 story ap…

I guess you're in the minority here. In Germany, everything Remotely large will be measured in football fields or "Saarlands".

I'm also European and don't get these olympic swimming pool or whatever comparisons. I'd have to look up how many m3 of water they contain or what's the length/depth in meters are to make sense of it.

Newspapers in my country don't make these silly comparisons.

But yeah, to be fair, when hearing about Starship I had to look up our TV tower height to identify whether Starship is taller or not. It disappointed me that it's not.

Yeah, height is easier to grasp when correlating in terms of x story apartment buildings.

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

#224

Post by ehnto »

ErroneousBosh wrote: post #156
hylaride wrote: post #145

Earlier quoted context omitted.

I think they misspoke when they said "in" the wheel, but supercars can have a separate motor for each wheel, and the closer they are to the wheel the better the torque as it's not also driving a longer shaft. The smaller the motor, the closer you can get.

I guess if you can make the motor and a suitable reduction box lighter than the equivalent bearing and driveshaft combination you could make the suspension arms mechanically simpler. By using motors at each wheel you'd eliminate the need for a differential, saving a good 40-50kg or so. Of course, if you kept the drive shafts and put the motor and reduction box in the middle, you'd be able to use inboard brakes and sa…

I wonder if that would be legal, or if there is a regulation about where you can put your brakes?

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

#225

Post by ajuc »

ehnto wrote: post #221
lunias wrote: post #198

Earlier quoted context omitted.

I wish more people on the road realized the extent to which weight reduction improves all aspects of the driving experience... it really does compound unlike any other change that you can make to a vehicle. IMO heavy vehicles are a scam and the antithesis of the direction we should be moving.

I agree with you however I believe weight and safety are in a complex relationship right now, which has nothing to do with performance and handling. Unfortunately I feel much less safe in a Fiat 500 when a significant portion of cars in the road weigh nearly 3 tonnes and perhaps can't even see me. I suspect most people are in SUVs because they're the pragmatic trade off between safety and convenience, not because the…

Tax SUVs out of existence.

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

#226

Post by jve »

port3000 wrote: post #124
bigtones wrote: post #100

Earlier quoted context omitted.

Americans are very weird when it comes to metric. They often quote mobile phones as having something like "a six inch screen size but now only 12mm thick" - pick a measurement system people !

The inch thing is because it's a screen: all screens are measured in inches pretty much everywhere, even in the EU

Yep, inches won for screen sizes.

Aaaand for various fittings for plumbers.

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

#227

Post by schiffern »

ehnto wrote: post #221
lunias wrote: post #198

Earlier quoted context omitted.

I wish more people on the road realized the extent to which weight reduction improves all aspects of the driving experience... it really does compound unlike any other change that you can make to a vehicle. IMO heavy vehicles are a scam and the antithesis of the direction we should be moving.

I agree with you however I believe weight and safety are in a complex relationship right now, which has nothing to do with performance and handling. Unfortunately I feel much less safe in a Fiat 500 when a significant portion of cars in the road weigh nearly 3 tonnes and perhaps can't even see me. I suspect most people are in SUVs because they're the pragmatic trade off between safety and convenience, not because the…

Classic prisoner's dilemma.

Everyone who can will naturally choose "defect" unless there's some sort of external coordination mechanism.

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

#228

Post by doph »

tckk wrote: post #94
thelastgallon wrote: post #76

Earlier quoted context omitted.

But why limit only to cars? Can this be used for motorcycles, e-bikes, electric buses, train wheels, e-unicycles, electric golf carts, etc? There are probably a range of application where in-wheel makes perfect sense.

Donut Labs markets a whole suite of axial flux motors. Sized from scooters through to large trucks. But no public pricing.

I don't think their motors are axial flux, they're just large and narrow to fit inside wheels. Or at least all the images on their website depict radial flux designs.

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

#229

Post by thesz »

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…

Tesla Model Y's battery is 771 kg. The motor in Model Y weights about 45 kg, about three times as much as the motor in the article. By reducing dual motor configuration weight from 90 kg to 28 kg, we reduce total powertrain weight by 7%.

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

#230

Post by ordu »

varjag wrote: post #20

The new YASA axial flux motor weighs just 28 pounds, or about the same as a small dog. But how many footballs a small dog weighs?

Lol. I was confused by it also. I have no idea how much is 28 pounds, and I could imagine how a small dog can be anything from 1 kg to 10 kg. It happens that the motor weight is ~13kg, but I'm still not sure that 13kg dog counts as "small".
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