Featured Awesome axial flux motor

What is cost and efficiency versus say the switched reluctance motors?

 

does it cut down on rare earth's?

 

Couldn't find any information but seeing as it is oil cooled itis doubtful that it is 99%, there is friction and heat from exciting the motor. The switched relcutance tesla motor has peak efficiency of 97% over a large rpm range. YASA seems to be saying lhigher power density in terms of power to weight and power to size, means it is more efficent as a system. That maybe. It currently is only going into super cars, which looks like maybe high costs, but perhaps low volumes and if volumes come then costs could come down. Would love some more information. Seems like a good choice for a motorcycle hub motor if costs can come down.

YASA says it uses less magnetic material than PM, but this is similar to claims by most hybrid motors like the switched reluctance.

 

Axial flux motors can be made with or without permanent magnets.

If you want to get rid of the rare earth magnetic material you need either excited field-rotor motors (serial, shunt, etc), induction motors, or pure reluctance motors. Of those reluctance motors are the most efficient but would likely need a transmission and multiple gears. The permanent-magnet-reluctance motors used in Teslas and Toyota hybrids (and perhaps others) have the advantage of having good torque over a large RPM range.

 

Nice concept. But who has licensed it? No press releases on their web site. Capacity of producing 25k units per year?

An idea/patent is proven good when it is making $$$$.

 

Yes they bought them as an independant subsidiery 5 years ago. This article tells the innovation that is trying to make this over 100 year old technology relevent.

Axial Flux Motor Powers Supercars to New Heights - IEEE Spectrum

Which gives a clue on why they currently are only in low volume supercars in the automotive sector. It probably is quite a high manufacturing cost. Perhaps with money from its parent company they can reduce costs. Tesla's carbon fiber wrapped rotors in its plaid cars uses a similar idea using expensive composite manufacturing techniques to reduce weight and add power (trade iron for carbon fiber which not only reduces weight but allows higher rpm allowing more power because the fiber allows hotter motors to run efficiently). Tesla is claiming they are working on manufacturing techniques to make manufacturing much cheaper. YASA just built or is building a new factory. We will know costs are down when mercedes puts it in a car that is less than $100,000 instead of these over $500K beasts.

 

For tesla it increases cost but decreases weight and increases power. The model 3/Y rear motor is 96% peak efficiency and is efficient in a wide rage. Tesla says they are working on reducing cost, if they do that I would expect it to appear in lower priced cars than the discontinued plaid model S/X. I do see a bunch of cybercabs being tested on the streets. First one was, what no rear window, but I guess if its driverless the camera is important not a human seeing through a window. If cf wrapped rotors become cheap enough I would expect them in the cybercab and the performance models first. Rumor was it was going into the model 2 which doesn't appear like tesla will ever make one.

One can hope that YASA or someone else can make these composites cheap to manufacture. Tolerances in the axial motor are really tight. Who knows. People didn't think lithium battery packs could be made as inexpensively as they are today. On a hub design axial makes a lot of sense, but in a car repair costs from vibration and inertia have made these an engineering difficulty versus inboard motors. We can hope manufacturing improvements can greatly reduce costs.

 

TBH I don't think there's all that much to get excited about when it comes to electric motors. The electric motors out there are already very efficient. Going from 95% to 96% efficiency isn't going to add any substantial range to your drive.

What would be nice is if they could substantially reduce weight, substantially reduce aerodynamic drag, and maybe figure out an alternative to rubber tires that produces far less rolling resistance. The ability to move a human being hundreds, if not thousands of miles on just a few kWh's is completely possible. But then we get into, "we need to still be driving the same stone-aged, rubber-tired bricks that were invented before the Model T because look at how the Tesla Model Y has the lowest drag..." Meh. Wake me up when there's actually something good coming from the automotive world.

 

I'm not sure which way of looking at the math makes more sense there. The other way is to say that going from 95% to 96% efficiency reduces by 20% the power you're still wasting there.

Maybe you don't care until you've improved other places where you might be wasting more. But supposing one day you have, then a 20% reduction here is nothing to sneeze at.

 

Ummm... let's get this straight here. I might have started off with a bit of an exaggeration (95% to 96%). But that's efficiency. And going from one to the other isn't going to cause a 20% change in power that's wasted or not.

When looking at efficiency we're mainly concerned about energy in and energy out. Miles-per-gallon is a measurement of energy being used, not power being used. You can use power in and power out, but you got to do a bit more math to arrive at X amount of kWh will get you X amount of distance.

But 20% power/energy wasted? What? That makes no sense. Where did you get that?

From what I can find, most EV motors are around 90% efficient. That means you have, at most, room to improve by 10%. And that would be insanely difficult. Realistically, it might be possible to go from 90% to 95%, which would improve things by 5.26%. So instead of 200 miles you get 210.5 miles, a whole 10.5 more miles.

But once you hit 99.999% efficiency, then what? Electric motors over 100% efficiency are impossible.

The real world advantage on the axial flux motor is it requires less material, and therefore is lighter by as much as 1/3 the weight of a typical elecric motor. But with going from the motor on the left to the motor on the right in vehicles that are thousands of lbs is basically nothing. It's about as advantageous as buying one less bag of groceries in order to reduce weight and save electrons.

Now don't think I don't appreciate the engineering that went into this. But there is no 20% improvement in not wasting power (whatever that's supposed to mean). There is no substancial reduction in weight for the entire vehicle. What it might allow is motors light enough to put in as hub motors removing any drive-train losses. But that still isn't likely going to help by any sort of 20%.

 

At 95% efficiency, 5% of the power being sent to the motor is being lost as heat.

At 96% efficiency, 4% of the power being sent to the motor is being lost as heat.

A reduction from 5% to 4% is a 20% reduction in the amount of power being lost as heat.

If you can then improve efficiency from 96% to 97%, your (already small) losses will have been further reduced by 25%.

If you ever get to 98% efficiency and then manage to improve it to 99%, you have cut your (by then very small losses) again, in half this time.

That's one of the things that makes this interesting. At every small increase in efficiency, you may have made your losses in that area so small that it pays to go work on other areas in the car for a while that may be losing more.

But eventually you may get all the other losses low enough to start thinking about these losses again, and at that time, what you can achieve with another percentage point efficiency gain can look interesting indeed.

 

Chap explained how this does reduce the waste heat at that one certain point by 20%.

This should also mean that the cooling requirements for that particular point are also reduced by 20%, which is also nothing to sneeze at.

 

You're right. Now I see what you're saying. But it is a vanity metric that proves practically nothing. Going from 99.999995% to 99.999996% is also a 20% improvement. But that doesn't improve range by 20%. And it doesn't reduce pollution by 20% either.

A 5,000lb wind brick that's powered by a giant electric battery that put's 92.7% of its energy into moving air and chewing up tires and this petroleum-gravel mix we like to call pavement and another 5% that goes to heating air just to move one person around is a huge waste of energy.