With the Chinese firmly in charge of the world’s supply of rare earth metals, the Japanese have been hard at work trying to devise means to reduce their reliance on rare earths in the manufacture of things like electric car motors. Now, researchers at Tokyo University of Science say they have done it. Their “switched reluctance motor” requires no rare earths, which could circumvent a major supply chain issue while driving down the cost of EVs.
Theirs is the first so-called switched reluctance motor with this kind of torque density, they say, though the researchers admit that it’s still not equivalent to the torque and efficiency produced by motors with permanent magnets. Simply, switched reluctance motors tap magnetic reluctance--it’s like electrical resistance, but for magnetism--in an electromagnetic coil. By turning the electricity on and off within the coil, a rotor inside is induced to spin, creating rotary motion/force (this is explained visually in the video below).
Switched reluctance motors have their drawbacks, particularly because they can be difficult to control. But better onboard, real-time computing is making them more reliable and less prone to vibration and noise. Moreover, the Tokyo team’s motor is about the size of the engine that goes in a Prius, meaning that it’s been scaled to a form that will fit in a standard small-sized production car.But most importantly, it means Japan may be a few design tweaks away from having an electric engine that doesn’t hinge on trade relations with the Chinese, who have been accused (not least by the Japanese) of bogarting their supply of rare earths (China controls 95-97 percent of global supply, depending on who you ask). And as far as what it means to you, the development of a dependable switched rotor engine with decent power and torque could lower the cost of EVs.
[PhysOrg]
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They should have spent their time developing iron nitride magnets.
Other Countries are doing amazing things. USA is falling behind in practically every category. But hey, we do excel at killing people and putting the most people in prison then any other country. So I guess we got that going for us.
Didn't Japan just find those billions of tons of rare earth metals in the mud on the ocean floor that they said they can suck up with a straw and use acid to separate the rare earth from the mud? Whither they did or not, keep up the good work Japan...the U.S. is depending on you.
P.S. Nissan has the best electric car in the world - the Leaf, so keep improving of those electric engines and batteries.
@boka We fall behind when we don't have a Government that supports innovation and cuts spending to groups like NASA. This country was a powerhouse due to the industrial age, and people were hungry for innovation. Now all we have is more and more control being shoved down our throats, which if we don't stand up as a people and change that. We are going be debt-shackled to other countries and we will be the cheap labor the world outsources to... We need innovation. We need to have no limits to our successes. We need people to get in the race with these other countries, so the world will look to us for technology once more.
So basically they created 50kW stepper motor and they are trying to drive it so that it's not stepping but rotating smoothly?
@ActionSeth - If I recall, funding for NASA has actually INcreased in the past few years. Just because the shuttle program was discontinued doesn't mean the money was revoked - they just put it into NEW technology and innovation rather than simply gliding on past accomplishments. Private industry is perfectly capable of picking up the ball where the shuttle left off.
I guess what I don't understand is how this COULD even come close to the torque required for a vehicle motor. Also, does a motor like this generate electricity to recharge the battery when coasting like traditional EV motors? Doesn't seem like it could - so there must be an awful lot of inefficiency to overcome. (Maybe I'm just missing information.)
Anyway, any technology that helps us to bypass the rare earth monopoly sounds like good news to me.
Tesla's Roadster motor is about the size of a watermelon, weighs 70 lbs and puts out about 200 hp. Smaller, lighter, more powerful, and NO magnets. Its called an AC induction motor, invented by Nickolas Tesla of course almost 100 years ago.
GM designed high power magnets about 30 years ago made from sintered iron under the brand name of Magna-Quench and then sold the patent rights to a Chinese company.
Rare earths are not rare. It is just that the Chinese under priced everyone else and took over the market.
It's not the price, but the conditions of production that gives China the edge. Rare Earth metals have a large number of radioactive inclusions, primarily thorium, that have very low market value, and must be dealt with. China has such abysmal environmental and labour standards that allow them to operate at greatly reduced costs (read: they could care less if they contaminate the countryside or if workers die, just as long as they are making the sweet coin).
This motor is an excellent example of engineers overcoming a material problem, in a greatly reduced time frame than trying to develop a new material to overcome a material problem.
I believe the leadership of our auto dealership is the problem. I believe our auto engineers are excellent. But it is such an ingrain genetic planned obsolescence auto industry. If they had the single purpose of making the best car possible, I do believe our USA auto companies would excel at this. And it would also require a better supportive work force in the manufacturing without it being dominated by union benefits... As they create hybrid cars now the price is extreme and still does not justify the saving in fuel\energy. These expensive hybrids naturally come with higher automotive insurance, because of their cost too. So where is the savings?
Here's American know-how and ability. This, seems to me, to be top of the line electric cars. The latest model comes in three types: 160 to 300 mile per charge. Fast charge in 45 minutes.
www.teslamotors.com
I just googled " In india a engineer is developing a air power car. "
Food for thought....
Here is the link I found.
http://www.mechanicalengineeringblog.com/1352-air-car-is-heading-for-mass-production/
Ever resourceful and innovative guys. Cheers to them for not letting China's rare earth supply dictate the game.. Fisher Capital Management News Directory
from Los Angeles, CA
Bill Dale
@ BubbaGump: yes, there have been air motors around for decades-- that's how many shop tools operate, such as impact wrenches, sanders and chisels. The up-side is that they're inexpensive, small, simple, rugged, and powerful for their size. The downside is that they are not appropriate for use in cars for several reasons.
The energy density of an air motor is low because, unlike an auto shop where you can have a huge compressor running all the time supplying compressed air supplied by efficient electric motors, an air-powered car must store its air supply onboard, and the higher you want to compress the air, the more robust and heavier your air tank becomes. You don't want an airtank with thousands of pounds of pressure exploding anywhwere close to you.
When you compress air (or any gas), it becomes hotter; when you allow it to decompress, it becomes colder. This is how a diesel engine ignites its fuel/air mixture.
When you try to compress air for use in a vehicle, the process is quite inefficient because you have to cool it off because the hotter it is, the more it resists further compression. Trying to pump air into an air car is similar to recharging a battery in an EV-- the closer it is to full, the more time it takes to top it off. The first few pounds are pumped in quickly-- the last few pounds are quite slow and energy-intensive. Recharging an EV to 100% can be done fairly quickly with state-of-the-art batteries and sophisticated electronics, but trying to top off an air car tank can be much trickier. The only way around it is to fill it slowly, and swap tanks out similar to how A Better Place replaces spent battery packs in EVs. It could work, but would be cumbersome. An EV, to me, would be preferable.
One of the curious aspects to air cars is that, despite short range between refills, they have the side benefit of free air conditioning-- the exhausted air from the motor is pollutiom-free and frigid due to the reduced pressure.
from Los Angeles, CA
Bill Dale
@ Clay Dillow--
Please do not use the words "ENGINE" and "MOTOR" interchangeably-- it's bad enough that the word "motor" is often used to describe anything running on fuel. But when you say that "The Tokyo team's motor is about the size of the engine in a Prius", you confuse everyone-- the Prius has both a gasoline engine and an electric traction motor, and the Prius engine is much bigger and heavier than its electric motor. It would clarify things enormousy if everyone always used "engine" to describe fueled power soirces, and "motor" to describe electric powerplants, especially as used in your article.
The Chinese don't control the world's rare earths. Rare earths are found in many places, including the world's ex-largest mine in California.
AMERICA gave up its supplies and stopped mining, it was the "green" thing to do.
All it takes is the WILL to go against the green religion and restart mining to take the Chinese monopoly off the table.
However, lowest cost, high energy magnets are always a good idea, but this overblown stepper motor isn't that.
jerrydd
Wow!! They built an EV motor that doesn't use rare earths!!
This would be interesting if we hadn't been doing just that for 140yrs!!!!
Using rare earths is in fact rare as few e motors use them going for cheaper PM's or better, variable field units giving far better control, 3x's the starting torque, lighter, more power/lb too.
I've been driving EV's every day for 15 yrs and the Only REE motor, 9hp I used burned up and replaced it with a 3.5hp series motor that was faster and could start up a hill, something the PM motor couldn't do.