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corodra

Don't get me wrong, I saw the title and was excited. I want this to be real.

I want to believe.

But way too many keyword drops. Disruptive is what red flagged me the most.

Way too many promises.

Only lab results and "experts" commenting that it should work in theory.

But no prototype?

Even though it's a different motor they don't "believe" it's going to cost more to make than traditional motors?

Only 3d renders?

I think there was a medical company that did something similar with blood testing. Didn't really work out for them.

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I've learned a great deal about motors over the years. I don't doubt what they have here is real, as, these principles have been known for a long time.

The reason we don't use permanent-magnet synchronous motors like this in cars though, is because rare earth magnets are much more expensive, and more fragile, than using synchronous reluctance motors which are mostly iron.

The auto companies aren't dumb --if they thought PMS motors were cost effective, they would have been using them by now.

The car makers with any volume are using asynchronous AC motors (Leaf, Tesla) or PM DC synchronous motors (GM). Tesla got a lot of publicity when there was speculation about the Model 3 using a reluctance motor, which suggests it would have been a new thing. But it turns out to be a hybrid of PM and reluctance. Possibly Chinese vendors are doing something different for cars, but the e-bike and scooter motors are all PM.

I don't believe the company in the article have anything at the level they are claiming.

Electric motors are remarkably good already. Even if it doubled the power for half the weight you still need lug along all those batteries.

Right, look at the size of the motor versus the size of the batteries in an electric car. Efficiency is already well over 90%, too.

If you managed to create an idealized electric motor that was 100% efficient, had no limits on power, torque, or RPM, weighed nothing, took up no space, and cost nothing, it would be a nice improvement but I don't think even this would revolutionize electric cars. Batteries are the key.

According to people on the TMC forums (so take with a grain of salt) Tesla's motors only cost $350-400. If that's true, they're basically perfect already. It's the batteries which drive cost and weight.

They are mostly iron so it seems plausible.

Is that the Model 3 motors? I've heard that the Model S motors had a surprisingly high failure rate, many owners of the earlier models having had 5+ drive unit replacements. I'm guessing the Model 3 drive units are more reliable?

The early Model S motors had problems like that. They got a lot better over the years. The Model 3's is great, and the Model S/X front motors are now the same as the Model 3's, while the rear motors are something else that's still a lot better.

Any clues what exactly within the motors fails?

There’s usually a funny noise long before any catastrophic failure, so I think it’s the bearings or the gears, but concrete information is hard to find.

I actually had my motor replaced due to this noise. It was a high pitched whining, kind of like a jet engine spooling up. Not real loud, most noticeable in a parking garage with the roof open, and I wasn’t even sure if it was abnormal, but I took it in and they replaced it. It’s easy to swap out, so they just put in a new one and then fix the old one at their convenience and give it to the next victim.

Incidentally, I had another weird noise sometime later which was a distinct clunking sound when accelerating from a stop. That turned out to be a bolt that wasn’t tightened properly. Oops!

Thanks for clearing it up!

Amdahl’s law of EVs.

Wouldn't that be with multi-motor EVs? ;-)

If you had a motor like that you wouldn't need batteries. You'd power the car with the motor :)

While motor efficiency is 90%, drivetrain is less than that because of gearbox. This motor claims to remove this inefficiency.

Tesla claims that their drive unit (which includes the motor, inverter, and gearbox) efficiency on their latest models is 93%.

Average or peak?

Making something that performs well at freeway speeds, yet also is efficient when manuvering round a parking lot is hard.

Most companies just hope you don't care about only getting 5% efficiency round the parking lot, because that isn't a large fraction of your energy budget, even when it's so inefficient.

No idea! Would it be expected for an electric motor to lose so much efficiency in that scenario, though? I though the variation was small.

Motor efficiency aside, a total “energy spent for distance moved” accounting will look bad at such low speeds, just because the car has to power non-motor systems and they use energy at the same rate no matter how fast you’re moving. Peak efficiency in a Tesla is at around 25MPH.

It must be peak. You could see how an electric motor efficiency map looks like here:

https://x-engineer.org/automotive-engineering/vehicle/electr...

A reduction gear is really not all that much of a loss, wind on the other hand-- that's a big one.

Airflow losses in big AC generators are solved by having the whole motor sealed in helium. The helium gas is used as a coolant too.

It would be hard to design such a system with a big enough supply of gas to survive leakage for the whole life of the motor though.

Airflow losses for a car will be dominated by the outside air. Surrounding the car with helium seems impractical, and hard on the occupants.

I thought these mostly used hydrogen instead of helium?

(and as an aside, hydrogen detecting sensors is an area of astounding complexity and cool effects which are worthy of an HN post all on their own)

I doubt hydrogen would ever be used because it makes metals brittle.

I'm pretty sure large generators used hydrogen at one point. I seem to remember reading about them using a palladium membrane to purify the hydrogen used to cool generators.

I am not sure why we are focused on the electric car angle. Assuming this motor design is legitimate and practical, I feel the implications for commercial/industrial prime movers and power generation are far more substantial. Hypothetically, if we were to replace all existing HVAC compressor and blower motors with this technology, where would that leave us in terms of power consumption reduction? How much wider do the applications become due to the variable speed capability of the motor design?

HVAC systems are far from theoretical peak efficiency. For example, notice how they all have a 'capilary tube' to restrict the flow of liquid coolant between the hot and cold sides of the system? That's like using your brake to go slowly round town rather than letting off he gas...

A small turbine rather than that capillary tube would instantly increase system efficiency...

It would be crazy loud.

Electric motors are already well over 90% efficient. I don't see what they could do to improve this. Maybe weight/power ratio? Even then, Tesla pretty much nailed it with his three phase "squirrel cage" motor. That's why even today that is what a Tesla car uses and it's what quadricopters use.

In the Fully Charged episode[1] linked in a recent thread here about some guy in Amsterdam making electric cars and boats, the guy mentions that the motors have brushes. I was mildly surprised as I just assumed they'd be brushless DC motors.

Are they just efficient enough that the cost/simplicity outweighs going brusless? Or are there other advantages to using brushed motors for electric vehicles?

[1]: https://www.youtube.com/watch?v=7zz3H0pSQ4Q

Perhaps it’s simpler and more efficient speed control circuitry. For a DC motor you just need to step down the DC voltage from the batteries. For a brushless motor you basically need a variable frequency inverter that’s necessarily going to be more complex and possibly less efficient.

Yep, mainly. You still need basically the same circuitry, but 3x simpler- you only need one phase instead of three. However you still need the same PWM-type controller to do it. The single phase can operate at several times lower speed though, which makes the output devices and gate drive much cheaper.

Brushed motors are readily available in the appropriate sizes in small quantities and used. Brushless motors not so much yet. Then you also have to use the OEM inverter which will take some reverse engineering or bring your own inverter. People are doing this with car conversions, but it's early days and anyone can wire up a brushed motor.

If you go distillate the actual claims from the fluff, the article is saying it has a larger torque to weight, smoother operation at low speeds, and larger efficiency at very high speeds.

And well, three is much to improve on the last two, so I'm willing to believe they got something for those, while I do expect the first claim to get completely lost once they actually produce the motor.

Cogging (non-smooth operation at low speeds) is pretty much a solved problem already. You simply program the cogging torques into the controller as a function of shaft angle, and tell it to compensate.

Final result: motor that behaves as if it had no cogging.

I had the same reaction. Reminds me of old claims for a 50 mpg carburtor (on cars circa 1970). There's definitely a fishy smell about it.

Golf mk i did 50 mpg with ease. It weighted next to nothing and was 60hp.

honda crx also.

“Reminds me of claims...”, and you want to talk about cars that were made well after the time period specified. That...kinda wasn’t the point.

The “time period specified” on your GP was circa 1970. The car mentioned came out in 1974.

“Well after the time period specified” seems like a stretch.

Yeah; my old GMC had a carburetor and the fuel economy is the same as the current replacement, which is the same size, runs half the cylinders (unless it needs all 8) re-levels into aerodynamic mode at speed, and has shutters that close the radiator grill when possible. (The new one is fuel injected, etc).

I’m not sure what fuel injectors and electronic ignition got the industry, but it wasn’t real world fuel economy.

Oddly, even current year light hybrids are advertising similar fuel economy as the old truck. I’m guessing it isn’t a technical problem....

I think a big driver for fuel injection and electronic ignition was reliability and meeting emissions standards.

Old style carburetor and mechanical ignition regularly required ‘real’ tune-ups and had horrible tailpipe emissions.

I'm also pretty sure the average sedan does 0-60 in the same time a 70's supercar. A BMW 330i can do it in 5.8 seconds. A Lamborghini Countach did that in between 5 and 6 depending on the model.

A Miura could do that in less than 7 seconds. And then would burst into flames ;-)

“I’m not sure what fuel injectors and electronic ignition got the industry, but it wasn’t real world fuel economy.”

Actually it is fuel economy. Your old truck [0] doesn’t have a bunch of mpg sapping emissions rules to deal with.

The fuel injector allow for more power for the same amount of fuel giving the engineer the power budget to spend on reducing non carbon emissions and increasing weight (ie safety)

[0] your truck appears to be tuned slightly lean, or at stoichiometry. Otherwise there’s no way you’d get similar mph.

> But no prototype?

See examples of this done right:

- https://en.wikipedia.org/wiki/Turbinia#Demonstration - Frank Zapata's "thing" on Bastille Day and the Channel crossing

Hmmm Are you suggesting that they might try doing a showy reveal?

Meh I'm okay with that. Maybe. But the amount of current publicity makes it feel like Theranos. That's why I have massive red flags being thrown up.

> Hmmm Are you suggesting that they might try doing a showy reveal?

If they don't, Theranos is the correct comparison. Put up or shut up.

On nearly any kind of coverage of an "amazing new innovation", the simplest sanity check you can do is check if they've filed a patent. If they haven't bothered, you'll be dead and buried before their work has any impact on your life.

Even if they've filed a patent, it could be complete garbage, like perpetual motion or energy out of nothing.

If what they say is 5% true they would have raised $50m seed rather than $4.5m.

I have recently converted to 100% electric for my automated transportation.

It is delightful in every way.

Its not difficult to view ICE automobiles with much disdain.

Go Electric or GTFO.

That's an amazingly weird response.

Did I say I was against electric cars? I even prefaced that I want this to be real. The problem is, I smell a scam in what they're offering.

You, however, have placed your identity with electric cars to give yourself value. Because you lack personal value. A type of identity politics, if you will. How about gtfo your soapbox and realize that you just told someone who is interested in an electric car future as anti ev.

I'm not reacting to you or attempting to dis-engage your view point .. I'm just saying, when electric is done properly and you use it as a daily, it really, really rocks. This may, or may not .. be an outlier to your point of view.

But truly, done properly, the end of ICE seems quite plausible.

Lots misleading in your comment but:

-they have built prototypes

-they know it will be cheaper because they eliminated the need for rare earth minerals

-Nothing in the article or video says they have actually built prototypes.

-They say it can be built without rare earth elements, but say nothing about how that affects performance. Everything else is for the magnet version and they use more magnets than is normal.

They do apparently have prototypes, but I'm still skeptical: https://www.youtube.com/watch?v=yqIKZGx-06Y

It's not a real demo though, in my opinion. If it was already in a car or used to power a lathe or something tangible, that to me is a prototype. Even a toy car is fine by me. In the video we can guess it's a prototype of a functioning motor. I guess. But let's be honest, there are prototypes for perpetual machines.

A prototype has to be real world functional. Doesn't have to be perfect or clean looking, sleek, etc. Just proves it can do a real world function. If it can't do anything useless yet, it's just a lab experiment or wishful thinking.

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