12 kw rc motor

[dangerzone]

I was at the AERO Expo 2010 in Freidrichshafen, Germany this April and there was a good idea for long range flight of electric airplanes. Since about 5kW to 12kW of electric power is enough for sustainable flight of UL aircraft then such an electric generator that could produce it would be great for long trips. Just put the generator on the plane or the co-pilot's seat and the range of the electric airplane can go for a few thousands of kilometers if a good fuel consumption is achieved... Some Simonini 2 stroke engines weight around 9 to 12 kg and consume 5l of gasoline for producing 12kW of shaft power, now the only problem would be converting that shaft power to electric power with minimal losses. Whoever comes with a solution might make a lot of money producing such small electric generators, imagine having them in any electric vehicle or airplane as a 'plan B' when something happens to the battery or the EV/EA runs out of 'juice'...

A few years ago I came up with something similar, but using direct drive from a 120cc paramotor engine fitted with a concentric electric boost motor for take off and climb, a bit like the configuration the Honda hybrid system uses. We didn't bother to build it as the total weight was greater than a conventional propulsion system and offered no real advantages. The problem with hybrid aircraft is the low ratio of peak to average power; average power is typically 50 to 70% of peak power, whereas for a car average power is often only 15% to 20% of peak power, making a hybrid solution more viable. Slow flying ultralights are probably the only case where it might just be viable, as they tend to have a higher ratio of peak to average power than other aircraft types, maybe around 2:1.

Jeremy

Have you seen the electric paramotors nowadays..? Some of them have quite a performance with some 10kW or even up to 20kW, better than a 250ccm ICE.

 

[sackspeed]

Dangerzone wrote:
Some of them have quite a performance with some 10kW or even up to 20kW, better than a 250ccm ICE

In Basse-Ham they messured the noise of these paramoteurs. It was only 54 db/A. The whole airfield was louder!!! These motors revs only about 2000 rpm.
This is ideal for a small light bike. I´m sure that`s the future.

 

[SplinterOz]

Ok Toolman2 and I just set this motor up with Burtie's timing adjuster.

Prior to using the timing adjuster we were getting the following:
Max RPM: 4700
Volts: 76
Max Current: 50amps (right at the peak 23amps under the 4200rpm mark.

Obviously we had some issues with the neutral timing or the sensor positions.

NOW we run it with the timing adjuster....
Max RPM: 6030
Volts: 76volts (same as before)
Max current: 5.5 amps
No load Power: 240 watts

Man this sings!!!

[youtube]rUwjLzmNWR0[/youtube]

If all these values are close (remember I have not calibrated the cycle analyst we were using and it showed -0.25amp draw with no throttle input) Toolman2 has come up with these numbers.

79Kv
0.124nM/amp
0.0088 ohms resistance
Peak Efficiency at 218 amp and 76 volts
Therefore 16.6kW
95.0% efficiency.

OMG... as toolman2 said I wet myself. :wink:

 

[HAL9000v2.0]

GREAT!!!
Great job guys. Really great!!! I wet myself 2!
I must say I never got this figures.
Is this with 36fet infineon?

 

[toolman2]

yep,
finally the colossus is running sweet for us, before this the amp draw unloaded was so high it smoked all the wires and was way to much of a mess to get any usefull data on, and we have burtie to thank for his really clever (1st prototype,-and works perfectly on every motor we throw it at) timing adjuster: http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=19054&p=334513&hilit=timing+controller#p334513.

finding the true no load amps seems to be central to calculating motor performance so now we have the numbers, and i reckon it adds up to a potential of 95% efficiency at 16.6kw of power! -feel free to check my maths etc. but that is now a fine motor..
and it was running tonys 24fet controller, so all these parts (motor, controller, and hopefully burties timing adjuster -hint) are off the shelf ES gear, that we can all get our hands on, plug in and get the same result!

 

[markobetti]

yep,
finally the colossus is running sweet for us, before this the amp draw unloaded was so high it smoked all the wires and was way to much of a mess to get any usefull data on, and we have burtie to thank for his really clever (1st prototype,-and works perfectly on every motor we throw it at) timing adjuster: http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=19054&p=334513&hilit=timing+controller#p334513.

finding the true no load amps seems to be central to calculating motor performance so now we have the numbers, and i reckon it adds up to a potential of 95% efficiency at 16.6kw of power! -feel free to check my maths etc. but that is now a fine motor..
and it was running tonys 24fet controller, so all these parts (motor, controller, and hopefully burties timing adjuster -hint) are off the shelf ES gear, that we can all get our hands on, plug in and get the same result!

RESPECT FOR USING ES knowledge ! Man that's rock and roll ....More shaft-roll than rock ..

 

[markobetti]

Did you do any load test ? i am interested in controller reaction at start

 

[SplinterOz]

No load testing yet (except toolman2 trying to hold the motor still while I turn the throttle).

I am waiting work from my fabricator to get the motor mount and wheel spacers done (hopefully no more than a couple of weeks). I can then run the motor on the bike and take it to a dyno.

Any ideas on a way to load test it before then?

 

[markobetti]

Did he stopp the motor ? If timing was right it would be harder to stop it than before ? or am i wrong..

 

[SplinterOz]

He was only able to stop the motor when the throttle input was very low, anything more and he had no hope.

 

[markobetti]

Okay, now i am convinced ....Burtie ,toolman , come up here and tell us what a heck do u expect under load ?

 

[HAL9000v2.0]

Did you start with sensors as is and advannce them linearly with rpm or did you advance them just once which means we should move them smewhere else.

 

[Burtie]

From the settings that SplinterOz posted here in the TA thread:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=19054&start=45#p343613

..the settings are:
Static : -12
Dynamic: -6
Ref RPM: 1000

So, 12 degrees static advance added to a linear ramp (proportional to RPM) advance of 6 degrees per 1000rpm.

This would give total advance @ 6000rpm of 48 degrees edit: (Electrical).

Burtie

 

[Burtie]

Okay, now i am convinced ....Burtie ,toolman , come up here and tell us what a heck do u expect under load ?

Testing of the timing adjuster component under a real mechanical load has not yet been done. Hopefully it will not throw any nasty suprises, but performance may suffer if the angular velocity of the motor changes very rapidly.

 

[HAL9000v2.0]

Ok so your advancer is a must. BTW great job !!!
If we move halls 12° backwards static advance will not be neccerery but then motor will have "better" direction. Now the sensors are in the middle, the pest position for CW and CCW so I'll say best is to leave it this way and use your advance both for static and dinamic.
I think infineon have some advancing function build in?!? But I guess it is not enough. 48° quite noticable ..

 

[HAL9000v2.0]

Just realized: Your advancer needs current sensing !!!
I use to work with MoTec programable fuel injection ecus. Something like fuel map will be nice and I see it like this:
X-axis = rpm
Y-axis = Amp
Z-axis = timing advance°

I realy, realy hope you will understand, because I don't know how to explain my idea. This is 4th edit.

 

[Burtie]

Hal, yes I think I understand your point ,to use the current reading as an additional input to control the timing.

LFP suggested some while back that throttle position input may be useful for the same reason.

There may well be advantages for using these signals combined with some mapping, and I intend to explore the possibility
in some future version . But for now I feel it is wise to try and keep things simple and learn what I can from the existing design.

 

[HAL9000v2.0]

Ofcourse this is more then enough progress, maybe I am jumping ahead. Can't wait to see load testing....

 

[Arlo1]

Splinter is that a 24 fet controler? Are you coing to put a full load on it? I am going to finish mine asap I am finaly caught up with buisness lol. I have 11 days off over xmass holidays to work on projects and this is one of them for sure!
Awesome guys. I am happy for someone else to finaly have full rpm!

 

[SplinterOz]

Arlo,

Yep 24 FET I will be trying a realistic load when I get the bike bits together in a few weeks. I am not going to test to failure and the controller is currently limited to 150amps.

 

[Arlo1]

Arlo,

Yep 24 FET I will be trying a realistic load when I get the bike bits together in a few weeks. I am not going to test to failure and the controller is currently limited to 150amps.

Luke warned me no mater what the current limit was set at to never put a load on the motor while I was running it. My controler blew just due to the fact I had 2 hall wires crossed.
I figure with proper current sensing it should be able to take it....
I am very excited for this!

 

[liveforphysics]

It would be ok to load it a bit at high rpms. just be willing to accept the risk of blowing the controller.

 

[SplinterOz]

I am going to apply some pressure on my fabricator to get some work done as soon as possible so I can get this motor mounted. Once done real load testing can happen.

Burtie says he will be doing some testing of the timing device with a loaded motor (not this motor) soon.

 

[Arlo1]

It would be ok to load it a bit at high rpms. just be willing to accept the risk of blowing the controller.

Its not the money so much its not the labour that realy burns me its the waiting to get controler parts all the way up to Canada!

 

[dangerzone]

yep,
finally the colossus is running sweet for us, before this the amp draw unloaded was so high it smoked all the wires and was way to much of a mess to get any usefull data on, and we have burtie to thank for his really clever (1st prototype,-and works perfectly on every motor we throw it at) timing adjuster: http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=19054&p=334513&hilit=timing+controller#p334513.

finding the true no load amps seems to be central to calculating motor performance so now we have the numbers, and i reckon it adds up to a potential of 95% efficiency at 16.6kw of power! -feel free to check my maths etc. but that is now a fine motor..
and it was running tonys 24fet controller, so all these parts (motor, controller, and hopefully burties timing adjuster -hint) are off the shelf ES gear, that we can all get our hands on, plug in and get the same result!

Wow, nice to see there's so much power, great job guys..!

I wonder what would be the peak power this motor could handle with a good controller..?