# is this to far out there for E.M.?



## Evilsizer (Jan 25, 2010)

using a mag lev system for no friction? something i have been thinking about when looking at windmill/turbines. Would this also allow for a higher transfer of power to wheels? would it also help in motor efficiency?


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## Georgia Tech (Dec 5, 2008)

Evilsizer said:


> using a mag lev system for no friction? something i have been thinking about when looking at windmill/turbines. Would this also allow for a higher transfer of power to wheels? would it also help in motor efficiency?


Not sure Evilsizer..... But hands down the biggest technical breakthroughs in this inustry will be in the batteries..by far! we master the Battery technology then EV will take over!


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## Evilsizer (Jan 25, 2010)

Georgia Tech said:


> Not sure Evilsizer..... But hands down the biggest technical breakthroughs in this inustry will be in the batteries..by far! we master the Battery technology then EV will take over!


for sure, you ever watch the planet channel? there was one show on it about future tech. one of them had to do with batteries, one scientist came up with using a Virus. that the same virus was used but some how made different for a postive and other for negative charge. then the glass would be coated with the virus and then layered to make the battery. as she was saying they are testing some 10k-20k different variations on the virus to find the one that will yield the highest energy density or something along those lines. been 6months or longer since i have seen that show. wish i could find it, was really cool to watch.


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## meanderingthemaze (Jan 25, 2010)

Not sure either. I've tried to ponder the idea myself, but I think you are going to be hard pressed to get rotary movement without some sort of physical contact somewhere in the design.

But, my imagination is there with you. I can see a completely suspended Wheel that is held to the axle in suspension by magnetic energy.

Maybe the design flaw would be the weight of the magnets.


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## Evilsizer (Jan 25, 2010)

meanderingthemaze said:


> Maybe the design flaw would be the weight of the magnets.


i think that is a possibility but not knowing if weight effects magent pull-force i dunno. From what i can see though with a strong enough pull-force or as im going to call it anti-pull force. they shouldnt come into contact. though i dont know the highest rating Pull force for magents. it will take some figuring to see what size/rating magnets will be needed to make sure no contact happens. i thought about trying to do a small scale model for a windmill project. in a way i think it could be carried over to a E.M. the only thing i need to look into is how E.M. work mechincally. to see if it really is possible to have a mag. lev. E.M.


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## Duncan (Dec 8, 2008)

What is an "EM"?

Do you mean an Electric Motor?

Are you talking about replacing the bearings with magnetic bearings?

You don't get much benefit simply because the current ball/roller bearings are so good

look for a 0.01% improvement


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## Evilsizer (Jan 25, 2010)

Duncan said:


> What is an "EM"?
> 
> Do you mean an Electric Motor?
> 
> ...


yea i figure E.M. for electric motor was good idea. well saying bearings to me means making contact. using magnetic to where they float in space/air, with the right pull force and same poles facing. it should keep from making contact.

Something that makes contact is as good vs something that makes no contact for rotational force?

i have the idea in my head i wish i knew how to draw it out. though the difference might be since i dont know what needs to be there for electric motors to work. that what im thinking wouldnt work for electric motors but be something that would be better suited to say a power generator.

*edit*
this is the video i watched that got me on the idea. taken a step further to have no friction at all while spinning.
http://www.youtube.com/user/GREENPOWERSCIENCE#p/u/69/PfZUmbxzUM4

ideas sometimes come from the weirdest things...


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## IamIan (Mar 29, 2009)

The concept is called magnetic bearings in the field... lots out there including companies that specialize in it from google searches... It is used often in items that need to have as little friction as possible ... It is a must for Fly wheels.

Yes it would greatly reduce friction.

Major issues:

#1> Massively expensive.

#2> Magetic flux of the E.M. during operation would influence the magnetic bearings ... so using it in an electric motor itself would be complicated.


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## Evilsizer (Jan 25, 2010)

IamIan said:


> The concept is called magnetic bearings in the field... lots out there including companies that specialize in it from google searches... It is used often in items that need to have as little friction as possible ... It is a must for Fly wheels.
> 
> Yes it would greatly reduce friction.
> 
> ...


Can you not use some kind of magnetic shielding between the mag bearings and rest of the motor. in that the magnetic flux wouldn't effect the magnet bearings.


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## few2many (Jun 23, 2009)

It's not like em field shielding for electronics. I'm not sure you can really shield magnetics that way.


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## IamIan (Mar 29, 2009)

Evilsizer said:


> Can you not use some kind of magnetic shielding between the mag bearings and rest of the motor. in that the magnetic flux wouldn't effect the magnet bearings.


Electric motors and Generators can be built to work with Magnetic bearings... some High End Fly wheels do this already ... it isn't that it can't be done... it just adds significant complexity and cost in order to get them both to function properly together... even the few experimental vehicles that have been powered by fly wheels have kept the expensive and complicated flywheel as a separate power source and have not even then build the same concepts into the electric motors or transmissions they used for the fly wheel powered vehicles.

So yes it can be done... yes it can reduce friction... but it is very expensive and have several complex issues to deal with.


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## Duncan (Dec 8, 2008)

*"Yes it would greatly reduce friction".*

*No it would not!*

The amount of energy used in modern ball/roller races is tiny!!

When you only have a tiny loss you can only make a tiny gain!

A 50Kw motor will have ball races that absorb less than 5 watts 
one in ten thousand!

99.99%

The bearing seals will have a higher friction

And you will still need bearing seals for a mag bearing to keep things out! 

Motors are not 99+% efficient because of other things -not bearing friction


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## IamIan (Mar 29, 2009)

Duncan said:


> *"Yes it would greatly reduce friction".*
> 
> *No it would not!*




I agree it would not greatly impact the efficiency of the vehicle ... or even the over all efficiency of the already high efficiency electric motor... but that is not the same thing as not being able to greatly reduce the friction.

I would call something like ~90% reduction in friction as greatly reducing friction... even 5 Watts reduced by ~90% down to 0.5 Watts is still greatly reducing that 5 Watts of Friction ... and ~90% reduction of the 0.5 Watts would also be greatly reducing that friction as well.

I will agree with the concept of even some theoretical 0 friction motor would not greatly increase the Electric motor's over all operating efficiency ... but that is a different issue from being able to greatly reduce the friction.... no matter how much or how little impact that friction has on over all motor or vehicle efficiency... the friction can still be greatly reduced.

So , sorry .... I'm going to disagree with you.

who are you quoting???

I would prefer 'it could'... instead of would ... and 'greatly' is pretty subjective... but either way friction could be reduced.

Even if it is overly complex , and far to expensive to be worth doing.


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## Evilsizer (Jan 25, 2010)

Duncan said:


> *"Yes it would greatly reduce friction".*
> 
> *No it would not!*
> 
> ...


well sorry but this makes no sense... i get now it wouldnt increase efficiency but still friction is friction. two surfaces making contact vs no contact all, imo is a big difference.

after thinking about it more, maybe im off. Would it not increase power to the wheels/power train with the motor having near zero or zero friction as it rotates.


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## San_Carlos_Jeff (Nov 7, 2008)

few2many said:


> It's not like em field shielding for electronics. I'm not sure you can really shield magnetics that way.


In specialty PCB applications Mu-metal is used to shield magnetic fields. Not sure what would happen in high magnetic force applications. IIRC Mu-metal is very pricey.


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## IamIan (Mar 29, 2009)

Evilsizer said:


> well sorry but this makes no sense... i get now it wouldnt increase efficiency but still friction is friction. two surfaces making contact vs no contact all, imo is a big difference.
> 
> after thinking about it more, maybe im off. Would it not increase power to the wheels/power train with the motor having near zero or zero friction as it rotates.


It could make a difference ... but it is not expected to give a big difference.

CSIRO makes an electric motor for Solar race competition cars that achieves 98% efficiency.

Some of the remaining 2% of input energy is lost to friction, some is heat, some is radio EMF , etc... etc... Not even all of the 2% is Friction.

That means even with no losses to friction we would expect less than 2% improvement from this already high efficiency motor.

That small % could be power ... but depending on other specifics it might just be more efficient and not provide any additional power.

Just a note ... Magnetic bearings as proposed here... do not create true Zero Friction ... But they can allow the creation of a very very low friction device... something that is needed for application where they are already in use.


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## icec0o1 (Sep 3, 2009)

Evilsizer said:


> well sorry but this makes no sense... i get now it wouldnt increase efficiency but still friction is friction. two surfaces making contact vs no contact all, imo is a big difference.
> 
> after thinking about it more, maybe im off. Would it not increase power to the wheels/power train with the motor having near zero or zero friction as it rotates.


Yes, it would.... by 0.01%. 

Here's a visual: How much effort would it take you to spin the shaft of a motor with your hands (no electricity)? Then, how much effort would it take to accelerate a car down the road?


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