Legit electric motor technology breakthrough?

MitchJi

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https://www.cnet.com/roadshow/news/linear-labs-electric-turbine-motor/

there were a motor that didn't need to spin as fast as that to make enough usable power and torque to drive a vehicle? If that existed, you could change all kinds of things about electric car design. If you didn't need a gearbox, you would save a good-size chunk of weight and, maybe even more crucially, space.

With that space, you could increase the size of your battery pack, and with the reduced weight, you would improve all kinds of things like handling, range and acceleration.

From the outside, the Linear Labs Hunstable Electric Turbine doesn't look wildly different from other electric motors, but inside is where things get a little wacky.
Linear Labs
A company based in Texas called Linear Labs thinks it's figured out how to make that magic motor and if it's right, it could change electric vehicles forever. Roadshow interviewed Brad and Fred Hunstable, the men behind this motor, who claim the Hunstable Electric Turbine (HET) produces twice the torque of a standard permanent magnet motor and three times the power and is more efficient while doing it.
 
Looks like it has axial and radial flux. That's a new one. Interesting idea.
 
https://www.youtube.com/watch?v=85nt9OhP6j4
[youtube]85nt9OhP6j4[/youtube]


https://webcache.googleusercontent.com/search?q=cache:JOTff7vx428J:https://www.linearlabsinc.com/why-our-motor/+&cd=1
Message from our CEO

The Linear Labs HET motor is not a traditional motor.

The best method today to achieve high torque output is a high speed motor with gear reduction or a large diameter motor. Therefore the industry goals have been to develop solutions to achieve ever higher and higher RPMs by various methods.

Hub motors are a brilliant idea. Unfortunately the current motors on the market have not proven to be the ultimate solution for the industry, neither the radial or axial flux hub machines have delivered on their promises.

The HET motor is the new paradigm in volumetric torque direct drive motors.

Our motor is a 3 dimensional circumferential flux 4 rotor machine. The HET motor is a new class of motor and these new motors currently produce torque up to an 8:1 gear ratio for the same size permanent magnet machine used today. This produces unprecedented high torque and very high efficiencies at low RPMs.

All the new R&D innovations today in power electronics, cooling, materials, mechanical designs etc. applied to the HET motor produce even more benefits.

We believe the drive system of the future is a direct drive system, no gearbox, no expensive high RPM mechanical designs with simple, less expensive power electronics.

This is the Motor of the World
 
Looks like the main part of the real 'innovation' is the mechanism they patented to enable the mechanical field weakening. That rotating drum in the middle of the motor that allows them to move the magnets out of phase.

Related to this, I suppose:
https://iopscience.iop.org/article/10.1088/1757-899X/100/1/012026/meta

And their patents:
https://patents.justia.com/assignee/linear-labs-inc

My brain is too tired right now to go try to understand those things, and I probably won't be able to do if I was awake either. The talk about 'one way magnetic field' is probably just a reference to using magnets arranged in a halbach-style array.

The halbach array type thing were you strengthen the field in one direction is already used in things like the Tesla Model 3 in IPM motors... that take advantage of reluctance and electronically controlled field weakening to do the things they do. Would a mechanical field weakening setup beat that?

The idea reminds me of a video I saw here with a big motorcycle-style hub motor during testing that had inside that could slide in and out to change the field strength of the magnets and allow the wheel to spin up and slow down easier.


Just pure speculation:
I am guessing that they have done the math to show their idea world improve the power/torque range of the motor and filed the patents, but don't actually have any real mechanisms engineered to do what they are claiming. If they actually had mechanisms that did what they described they would, you know, show them. Instead of just artistic rendering of what the motor could look like and 3d models.

Of course I could be wrong.

As with everything the real challenge isn't so much modelling or testing innovations, but actually making the innovation into something useful that can be actually manufactured. Then manufacturing it.
 
Pretty obvious from their videos and marketing materials that their initial market will be "upscale" -- i.e. military, industrial, aeronautics, and certain construction technologies where there would be a premium for fail-safe operation. I can't see them moving downscale anytime soon.
 
MJSfoto1956 said:
Pretty obvious from their videos and marketing materials that their initial market will be "upscale" -- i.e. military, industrial, aeronautics, and certain construction technologies where there would be a premium for fail-safe operation. I can't see them moving downscale anytime soon.

First product using the technology purportedly releasing next year is a scooter, so.. maybe not?

They're looking to license the tech to others, not small scale manufacturing for niche use cases.

On the technology front there are a few things that are of interest. As was touched on earlier, the ability to via mechanical means extend the operational range beyond the static wound KV without the efficiency loss of opposing current is intriguing. The other thing that I found very interesting was the wiring topology results in zero end turn losses, however with the orientation being different from axial flux designs it allows for cooling tubes right through the center of the copper coils which should result in quite excellent cooling capability.

Need more details!
 
Why is my bs detector going off in overdrive? A few thoughts:

--We already have really efficient, really high output radial flux motors and axial flux motors that do slightly better. We're talking high 90s% efficiency and >10kw/kg without needing complicated builds and last-century "mechanical timing adjustment". They will be made cheap by economies of scale. So, like, how does this improve on that? It doesn't. It takes good simple motors and makes them more complicated for no reason.
--My gut feeling is that by combining axial and radial flux you end up with a motor less good and more complicated than if you just chose one of those designs and optimized it
--mechanical timing, why not just electrical timing aka flux weakening? The effect should be the same and more elegant.
-The talk about eliminating the gearbox implies a multi-speed reduction. It's already a solved problem that multi speed gearboxes are undesirable for higher power electrical traction applications. This technology will need a single-speed reduction like any other high power density motor. It's not claiming the second coming of torque density. The need for single stage reduction in high power density motors is an inherent result of how fast the wheels we use to drive vehicles turn at the speeds we drive, and how fast a high power density motor wants to turn.
 
This may only be a percent or two more efficient comparing peak to peak with current technology, but the potential for it to extended the efficiency plateau significantly in both directions is something that will need to be considered.

Flux weakening increases RPM but with a fairly significant torque penalty even with motor designs that don't take a massive efficiency hit (IPMs).
 
Grantmac said:
Flux weakening increases RPM but with a fairly significant torque penalty even with motor designs that don't take a massive efficiency hit (IPMs).

Worth noting that their "mechanical field weakening" will not avoid the torque penalty. By mechanically field weakening you reduce the effective strength of the magnets and thus get less torque, same as with IPMs. It's physically impossible to make a motor without this problem.

The difference is you don't need to inject d-current, which is accompanied by resistive losses. Unfortunately, at high speeds the losses in the motor are dominated by core losses which d current only has a minor effect on.
 
I don't see the commercial sense behind changing a simple electronic field weakening system (the standard one where its done in a bit of software in the controller) for an expensive mechanical field weakening system...
 
tmiddlet said:
Grantmac said:
Flux weakening increases RPM but with a fairly significant torque penalty even with motor designs that don't take a massive efficiency hit (IPMs).

Worth noting that their "mechanical field weakening" will not avoid the torque penalty. By mechanically field weakening you reduce the effective strength of the magnets and thus get less torque, same as with IPMs. It's physically impossible to make a motor without this problem.

The difference is you don't need to inject d-current, which is accompanied by resistive losses. Unfortunately, at high speeds the losses in the motor are dominated by core losses which d current only has a minor effect on.

echo's my thoughts - why add the mechanical complexity of mechanical field weakening when electrical FW can have a minimal impact on efficiency? moreover if you put the weight of that mechanical FW into more copper an iron, I wouldn't be surprised to see any performance gains evaporate entirely, if not have this motor loose out to the higher copper and iron content motor.
 
I see plenty of detractors on here...

Why is everyone so cynical?

Perhaps it's just the nature of internet interactions...

I'm just going to wait and see and hope for something interesting.
 
https://endless-sphere.com/forums/viewtopic.php?f=30&t=105034
Archer321 said:
I'm just going to wait and see and hope for something interesting.

me3.
but as an amerikan pwezident was fond of saying...
trust but verify depends on what the definition of 'is' is.
fool me once, shame on me. fool we twice, uh, won't get fooled again.
meet the new boss, same as the old boss magic bus quadrophenia.
 
The talk about eliminating the gearbox implies a multi-speed reduction

Their proposal was poorly worded,and I believe they are implying that improving the torque of the motor (I would call it a combined radial and axial-flux), might mean that "for certain applications" you don't need the one-speed reduction. If I am right, then I feel that they are exaggerating the benefits.

Imagine a direct-drive hubmotor, and compare it to a geared hubmotor of the same size, If you combined a radial and axial-flux internal configuration, I do believe the DD hubmotor would have more torque with no other change. I believe they are implying that removing the one-speed gear-down would be a huge benefit.

Whether someone loves the Teslas or hates them, the one-speed gear-reduction on a Tesla motor (similar in principle to the planetaries on a MAC) is compact and reliable.
 
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