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anigbrowl
Good article & technological work, but good luck finding collaborators with the arrogant attitude radiating from that headline
qbrass
Made even worse since it probably wasn't the authors who gave it that headline.
sunstone
As I recall Siemens has an electric motor that weighs about 100lbs and puts out over 300hp. So yeah, it's all about the batteries still.
TD-Linux
Yeah, it's a neat motor design, but it doesn't support the headline - 6% greater power to weight of the motor.
rurban
No, it's not. Doppelbauer is absolutely right. He just forget one key strategy with these high dynamic dynos. You make them longer, called cigar. The longer, the more area to apply the force. But then you've got a problem with the tyredyno design. The best cigars are 150cm's long, the ones used to test the best F1 engines. Those are handmade in low numbers, and extremely powerful and sensitive. They always need to need to know the exact absolute angle of the rotor, which is a hard mechanical problem. Wrong cooling fluid will break the engine. Only very few such engines do exist, but they are multitudes better than any cheap engine. Such dynos usually win F1 championships.
schiffern
>There are two kinds of AC motor: asynchronous and synchronous. We will focus on the synchronous ones because they generally perform better and more efficiently.

fwiw Tesla disagrees. True the peak efficiency is better, but the average efficiency is worse.

https://www.tesla.com/blog/induction-versus-dc-brushless-mot...

lithos
Synchronous motors can be nice where you have predictable loads, well thought out maintenance schedules, and few surprises. Or worst case just can't deal with AC.

Almost nothing falls in that category.

sc0ttyd
Not even gonna read it even though I might be interested, due to the patently false clickbaity headline
tdb7893
Generally it is perfectly valid to judge a book by it's cover but the article is actually pretty different in tone from the headline so I think it's actually worth a read.
FullyFunctional
The headline promised a lot but the article delivered "4.4 percent less energy". Also, I find it interesting that the motor Tesla uses isn't even mentioned (and AFAICT doesn't fall in categories they compare).
rausk
Could it still be about the batteries: https://en.wikipedia.org/wiki/Energy_density

Seem it is hard to beat the WH/kg of chemical energy storages with electrochemical energy storage.

sliverstorm
I agree we could really use improved batteries, but- You may not have to beat chemical energy if you can improve aero, weight, and efficiency.
SigmundA
Tesla S motor and inverter weighs 350 lbs on par with an ICE. The battery however weighs 1200 lbs while 20 gallons of gas weighs about 120 lbs.

No its all about the battery weight, and cost.

alberthartman
So if you make your motor 10 pounds lighter you win? Heck, my backpack is 10 pounds. And a motor can only be 100% efficient, and they're at 97% now. Naw, I'll take my non-slipring motors.