I wonder if this tech is gonna reach us in time.
80% of the power loss is reduced according to the sources I have seen.
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I’ve never seen efficiency ratings on our motors, but there are a lot of ebike motors that claim to be in the mid to high 90s for effeciency.
I don’t know if they have that data “on paper” or became a reality and they have working long lasting prototypes. I have read the same news at many different sites but the same info is provided.
The article says 10% loss as heat. Id says thats a pretty shitty motor then. 95% efficiency at specified load is acceptable to industry standard.
Cool article from abb, world record of 99%.
Its megawatt size tho;
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Interesting video
Even with a complex liquid cooling setup I doubt there’s anywhere a fiber filled plastic would work in any motors we use. carbon composite can be used on the outside of the rotor instead of the iron bell and aluminum support if willing to do a hallbach array but otherwise it needs to be iron. The stiffness is needed. Or maybe u could use a carbon shaft? I don’t know if carbon takes torsion well.
https://dragonplate.com/dragonplate-carbon-rod-8mm-x-48
I can’t think of anything else that could be lightened on a motor. Except as I say the rotor done in carbon would be a great drop in weight and w the hallbach a great increase in performance too. Surprised more motors we use don’t do the carbon n hallbach rotor especially since their most often put in a plane looking for max power to volume n weight. Reminds me I have a motor here and still haven’t gotten around to dropping the rotor in a cup of acetone and see if it will breakdown the magnet glue then glue them back in adding others making a hallbach. If there’s an “easy” way to make a motor way more efficient that’s it.
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More motors don’t use halbach arrays because they are difficult to construct using assembly line machinery and they will demagnetize each other, so you have to be really careful with things like heat. Halbach arrays are only meaningfully effective at larger air gap distances and they alllow for fewer turns for a selected motor Kv.
The motor used in the model 3 is a salient pole synchronous motor, it’s a combination of a reluctance and permanent magnet, nothing new here. The use of permanent magnets actually limits maximum power output and operating range because you can’t vary rotor excitation like in an induction motor.
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Ok here’s a stupid idea 
3d printed PC can, iron tape all around + carbon fiber coating sandwich + magnets epoxied inside.
I’m not sure how lighter it would be given out will require multiple layers. No ideas for the shaft.
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i see the hallbach can be demagnetized more easily if exposed to a strong enough field or with the magnets being smaller. (I see in motor analysis software they will give a field strength at which it would occur). They’re more difficult to construct but still surprising some primo manufacturer hasn’t made the extra steps considering the benefits. A carbon rotor with a hallbach would be super bling. And a carbon shaft for the Uber premo power to weight win
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Magnet manufacturers have tested the effectiveness of a halbach array, they provide no additional benefit when the airgap is small. Basically in most motor constructions they only come with downsides. Since the magnets are all working to demagnetize each other, I would guess they demagnetize at a lower temperature.
Also, most of the weight comes from the battery and other stuff, reducing the weight of the electric motor gives minimal benefit. This is even true for electric skateboards. My board weighs 30 pounds but the motors themselves are only 4 pounds total.
The biggest thing dragging electric power to weight is the damn battery.
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In my simulations hallbach is a great improvement in a motor.
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What’s the airgap between the stator and the rotor? What is the Kv difference? Simulation and reality often don’t match up.
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I have the model with the air gap at .5mm. I forget the details but remember it producing 20% less electrical resistance for same output
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Sandy Munroe did say they have some magic glue that held them altogether… it could be that only Tesla was worthy to wield the weapon of mass torque. This Halbach Array “secret” tech is fascinating indeed! We could be onto something here… I am certain they have gone beyond basic Hallback Arrays. Each magnet is designed in such a manner that Munro does not know how to reverse engineer them yet. (I doubt he ever will).
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For all we know, the actual effect of the halbach array could be marginal, and the entire design is just another marketting gimmick. There is a reason why it has not been widely adopted in industrial machinery, or has been adopted but not publicized.
Did you watch the video? The teardown was definitely no marketing gimmick. It is essentially almost impossible to do, potentially alien / off-world tech. woo woo.
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Sooo, marketting gimmick.
No. I read a comparison a while back between the motors that Tesla, Porsche, and others were using. Tesla’s motor was as powerful as the others while being physically smaller and lighter. The difference was noticeable, but not huge.
I’ve also played a bit with hallbach in simulations, there is a considerable improvement in efficiency, so not a gimmick
I haven’t watched this video yet, but from what I understood they use hallback simply because it allows them to use lower grade, cheaper magnets while still having an acceptable flux density
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https://www.google.com/amp/s/arstechnica.com/cars/2019/04/motor-technology-from-model-3-helps-tesla-boost-model-s-range-10/%3Famp=1
I’ve always heard the model 3 was a version of a switched reluctance motor, which doesn’t have magnets but just iron in the rotor that is pulled by the coils but the 3 uses magnets in the stator just to shape and direct the magnetic field better.
Strange as looking at the video it seems the magnets are in the rotor but it’s not clear.
If we spun our motors much faster and we’re able to gear it and then get needed torque that way we could get away with a switched reluctance motor but since we aren’t spinning them fast we need the torque enhancement of the magnets is my understanding
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