40kW motor?

[Jeremy Harris]

http://www.freeair.cz/freeairen/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=168&category_id=49&option=com_virtuemart&Itemid=53

Looks interesting, the weight is only 8kg, although the price is a bit steep.


They also do a 20kW version: http://www.freeair.cz/freeairen/index.php?page=shop.product_details&product_id=167&flypage=flypage.tpl&pop=0&option=com_virtuemart&Itemid=53

Jeremy

 

[AussieJester]

Anodized blue with lightening holes... :: druels on keyboard ::
but 1600 euro :-| First Rodgah, then Timma now you tempting me with 'da "bling"
what are you doing to me Jeremy i thought we were buddys LOL... :lol:

These would be ideal for an electric paraglider i'm thinking Jeremy?

KiM

 

[simi1970]

Prototype of this motor in action
[youtube]jEEtCykXlsI[/youtube]

 

[Jeremy Harris]

Anodized blue with lightening holes... :: druels on keyboard ::
but 1600 euro :-| First Rodgah, then Timma now you tempting me with 'da "bling"
what are you doing to me Jeremy i thought we were buddys LOL... :lol:

These would be ideal for an electric paraglider i'm thinking Jeremy?

KiM

40kW would be way more power than you need for a paramotor, Kim, but the 12kW motor is pretty much ideal. My paramotor is a 120cc two stroke that peaks at around 20hp (probably around 15 to 18hp usable), and that's right at the very top end of the sort of power you need, as it's 56kg of static thrust is more than enough to push you on your face on the ground if you're not careful. More power in the air just makes you pitch up and climb faster, you don't fly any faster as that's fixed by weight and wing area/design.

Nice motors though and definitely worth watching as possibles for high end builds.

Jeremy

 

[grindz145]

Since it's so expensive, it might suggest that you can actually get 40kW out of it...

 

[TylerDurden]

Nice start...

I look forward to seeing the cooling system.

 

[John in CR]

The controller for it will probably cost and weigh more than the motor, otherwise it seems perfect for an electric motorcycle.

 

[AussieJester]

40kW would be way more power than you need for a paramotor, Kim, but the 12kW motor is pretty much ideal. My paramotor is a 120cc two stroke that peaks at around 20hp (probably around 15 to 18hp usable), and that's right at the very top end of the sort of power you need, as it's 56kg of static thrust is more than enough to push you on your face on the ground if you're not careful. More power in the air just makes you pitch up and climb faster, you don't fly any faster as that's fixed by weight and wing area/design.

I did see that one posted also Jeremy it is also alot more affordable too. Only had a quick look last night before bed
and didn't realize they were outrunners till seeing the video either, i would interested in the 12kw motors for myself
as i have been about the large colossus and the 14kw astro in the works, but it still a matter of something thats affordable and able to run them at their rated capabilities...hrmmmz, There's rumors about an English gent, recently retired very clever individual thats working on some serious but simple controllers i wonder if he could be enticed to "upgrade" those to suit these monster motors....complete with blue anodizing and lightening holes of course

KiM

 

[liveforphysics]

So, I'm thinking about buying one, but what is up with this 280euro tax BS on top of a $2300usd motor?

 

[katou]

I thought that the power limit had been reached, not because of motor tech, but controller tech.

Isn't that what's stalling the Colossus thread?

I'm guessing that controllers exist to run this beast?

Katou

 

[jag]

So, I'm thinking about buying one, but what is up with this 280euro tax BS on top of a $2300usd motor?

That's the VAT tax. You won't be charged that when they ship it for export, but look out for US import duties and UPS brokerage fees of at least similar amounts...

kV seems a bit unpractical unless one wants to plumb ones vehicle with copper as thick as water pipes.

 

[Biff]

I doubt that it would do 40kW for very long, at 90%efficiency that would be producing 4kW of heat, which would be very hard to get rid of with only air cooling in such a small package.

The 40kW performance chart says a little bit, the power only goes up to about 17kW which is closer to what I would expect that motor to go. I wonder what controller they recommend / used.

-ryan

 

[Jeremy Harris]

So, I'm thinking about buying one, but what is up with this 280euro tax BS on top of a $2300usd motor?

As jag says, it's VAT which is the same as sales tax in the US. Here in Europe we have a system where sales tax is charged once by the vendor in the country of sale for all sales in the EU and goods are then imported tax and duty free into other EU countries. It speeds up shipping and avoids cross border problems, like those you guys have when shipping stuff across the Canadian border, high handling and import charges, for example. The downside is that VAT ("Value Added Tax.......") is high, typically 15 to 20% depending on the particular EU country.

VAT is not payable on exports to countries outside the EU, so you can knock off the 20% Czech Republic VAT from the price, but, as jag rightly says, you may well get hit with Federal import duties and taxes, and maybe State sales tax as well (I can't recall whether you guys have to pay State taxes on imports).

I doubt that it would do 40kW for very long, at 90%efficiency that would be producing 4kW of heat, which would be very hard to get rid of with only air cooling in such a small package.

The 40kW performance chart says a little bit, the power only goes up to about 17kW which is closer to what I would expect that motor to go. I wonder what controller they recommend / used.

-ryan

I agree about the heat, but I think that the performance plot may be for half the motor. At the top it says "40kW /2" which is the low Kv version, which I would guess is only capable of about half the power of the "40kW /1" version with it's much higher Kv. The winding resistance for the high Kv version is stated as 1mohm, compared with 6mohms for the low Kv version, which would indicate that the I²R losses are massively reduced. They do say "with cooling" in the spec, but it's not clear how this motor is cooled. I'd have thought that an internal water cooling system, like that which Hal's developed, would be the best way to cool an outrunner like this.

Jeremy

 

[Biff]

The winding resistance for the high Kv version is stated as 1mohm, compared with 6mohms for the low Kv version, which would indicate that the I²R losses are massively reduced. They do say "with cooling" in the spec, but it's not clear how this motor is cooled.

I didn't notice the 40/2 and 40/1 I wonder if that means 2 turns per tooth and 1 turn per tooth.

The I²R are not really reduced with at a given output RPM and Torque with different windings. With 1 turn you would need 2x the current to produce the same torque, so therefor you would have
(2I)²1mOhm = 4*I loss, which is pretty much the same as the loss as the 2 turn motor (I²*5mOhm), given the relative poor precision of the values they provide I would assume they would be the same. I believe the only reduction of resistance by going to fewer turns is the savings of end-turns, and possibly slightly better fill factor

And as you sated "With Cooling" is very generous. It could mean in a liquid nitrogen bath I suspect, like most of the RC airplane motors, the 40kW is a 5 to 10 second peak power.

-ryan

 

[liveforphysics]

Fortunately, burst power is all I need for a drag application. I figured if you started with it frozen with CO2, it would handle at least 200hp for 10seconds. Good enough for my needs.

 

[Biff]

Fortunately, burst power is all I need for a drag application. I figured if you started with it frozen with CO2, it would handle at least 200hp for 10seconds. Good enough for my needs.

You , my friend have a sick mind

Although you are correct, for a short time it would deliver a lot of torque, but it might not produce as much as you hope.

There are limits to the magnetic flux density in the iron, and the coercivity of the magnets will also limit performance. as you reach those limitations your torque / current constant starts to be reduced, so 2x the current won't produce 2x the torque. I suspect that at 40kW is starting to push the magnetic properties of the motor, so you are starting to run into the reduction of torque/current, so if you tried to put 2x the 40kW current at the same speed, you might only get 1.5 x the torque so only 60kW out, and probably risk damaging the magnets. I expect it is not physically possible to get 150kW (200hp) out of that motor, no matter what cooling you have. If you want, you should be able to calculate the theoretical maximum power using the back of the napkin calculations from Shane Coltons thesis at around page 42 http://web.mit.edu/scolton/www/SCThG.pdf based on the data sheet for the motor you can figure out how much current would be required, then determine the flux density in the tooth, and see that things won't add up.

-ryan

 

[liveforphysics]

Yes, tooth/magnet flux saturation limits are kinda a bitch.

Much like making boatloads of torque with an ICE, you reach a point where the only path is to increase RPM.

I've got a 10,000ft spool of carbon fiber yarn I can wrap that rotor up and epoxy with in my lathe, install premium ceramic bearings, have the rotor dynamically balanced, install CO2 spray nozzles inside and outside that stator, turn it into a frosty critter, then find that saturation "knee" in the Kt curve, and make sure my phase current's don't exceed that point by much, and gear it to spin up to the point it's knocking on the door of mechanical destruction, and let the CO2 handle the extra heating from increased eddy/hysteresis/iron etc.


Coming from an ICE racing background, the idea of making a machine that doesn't have reciprocating parts operating at a higher RPM range seems so dead simple compared to what we go through trying to control valve/piston etc motion at 12,000-13,000rpm.

 

[Biff]

If you can get it to spin at that speed, it could produce the power. You will have one heck of a time controlling it, since the inductance will cause serious current lag at such high frequencies, and the core loss will be significant aswell. You might have better luck building your own motor from scratch with fewer poles to reduce the electrical frequency. I am working on a 10 pole design and will be ordering prototype laminations, and custom magnets. If you are interested in buying some for yourself, send me a PM. If I order enough I can get them stamped rather than laser cut which would reduce the cost of future lamination runs.

-ryan

 

[liveforphysics]

10 poles does sound a lot better for higher speed operation.

PM on the way.

 

[texaspyro]

Fortunately, burst power is all I need for a drag application. I figured if you started with it frozen with CO2, it would handle at least 200hp for 10seconds. Good enough for my needs.

Heck, that's less than 500 Wh per run. A 24S 5000 mAh nanotech could do that... but you would probably have to go 10P to get the current (and 32S to get over the wiring and controller losses)... but then you could draw over 600hp and still not push the battery. Maybe gang four of these puppies?

 

[Arlo1]

I just found this thread lol. Where do I look for custom lams?

 

[Miles]

Where do I look for custom lams?

http://www.protolam.com/

 

[Arlo1]

Thanks Miles. I found them a little while ago and fired off an email.

 

[Biff]

for the best price and excellent service, try these guys

http://www.polarislaserlaminations.com/

they don't do design, but they can turn any propper engineering drawing into laminations for you.