My next turbine

[fabricator]

It's a 4:1 sprocket and chain machine 60 tooth on the input and 15 tooth on the output, right now I have a 40 turn 13 awg test coil in it, it has 2 x 1 x .5 magnets, the ones with the 3/16ths roll pin hole.
Here is a link to a video of it running up to about 500 rpms just for the heck of it, that coil got warm to the touch http://s2.photobucket.com/albums/y6/fabricator01/?action=view&current=MOV01327.mp4
 
And some regular pics.

[jarrod9155]

Now that's pretty cool.
  On the coupling  or sleeve did you use a slotted key or just set screws in sleeve. The piece that the rotors connects to . I ordered couplings with set screw but couldnt find keyed ones with the slot also .What  was the method you used to connect the rotors to the sleeve  . My direct drive unit I am building is on the same idea for the shaft and bearings .

[GoVertical]

Greetings, Great work. In the video was there a load connected to the coil?

[fabricator]

Now that's pretty cool.
  On the coupling  or sleeve did you use a slotted key or just set screws in sleeve. The piece that the rotors connects to . I ordered couplings with set screw but couldnt find keyed ones with the slot also .What  was the method you used to connect the rotors to the sleeve  . My direct drive unit I am building is on the same idea for the shaft and bearings .

The hubs are from Tractor Supply, they stock a wide variety of shaft sizes, they are keyed, the inner rotor should be keyed, then you use spacers to set the air gap, the outer one can just use set screws because once it gets close to the inner rotor it aint gonna move around at all.

[fabricator]

Greetings, Great work. In the video was there a load connected to the coil?

Nope, open circuit, I'm shooting for a 25 volt cut in at 80 rpms.

[ChrisOlson]

It's a 4:1 sprocket and chain machine 60 tooth on the input and 15 tooth on the output, right now I have a 40 turn 13 awg test coil in it, it has 2 x 1 x .5 magnets, the ones with the 3/16ths roll pin hole.

29.75 volts out of one coil.  All you need is gears.  

You're going to like that machine a LOT when you get it flying.  That little 12 pole 9 coil generator on my 12 foot geared machine has been pushing well over 2 kW today on a regular basis and the dang thing pumped out 12.66 kWh since this morning.  It'll be interesting to see how yours sounds on the tower.  My 12G hums pretty loud at around 250-300 watts then sort of quiets down until it gets to about 1050 watts where it makes a sort of definite hum in the tower about like a big electric motor running at full load.  Then about 1100-1200 watts it sort of quiets down again and at about 1800-2000 watts it makes a LOUD howling sound.  Once it gets above 2 kW or so then it sort of quiets down again.

The generator is running at about 800 rpm at 2 kW and it must be right at a speed where the vibration causes a resonance in the tower.  It's pretty cool.  My wife knows by the sound of it how much power it's putting out.  She was in the kitchen this afternoon and it hit that howl and she says, "Honey - the turbine just hit two kilowatts".  LOL!
--
Chris

[fabricator]

I forgot to mention that all the blame for my turn to the dark side is Chris's fault, his cool machines drove me to it, without his ideas and support I wouldn't be here,  thanks Chris, I get bored easily without new challenges.

[jarrod9155]

What size shaft is that ?the big one

[fabricator]

What size shaft is that ?the big one

It's 1.5" chrome molly, mostly just because I had it in the rack, you can order it right from McMaster Carr, on line.

[jarrod9155]

I ordered a 1-1/2 also through fasentall for my direct drive just carbon steel 3 feet long .
Thanks
Jarrod
  Maine

[zvizdic]

Is it 16-17' mill ?

If so you going to need a truck to haul all this Watts.

[fabricator]

Is it 16-17' mill ?

If so you going to need a truck to haul all this Watts.

Yep 16' it's gonna use the RWS blades too, it's prolly gonna be a handful until I learn how to handle it, but fortunately Chris has a new wrinkle on that end too, but that's a whole nuther ball of wax for him to explain sometime maybe.

[windy]

Fabricator,
 Will be interesting to see it up and running. I am wondering what kind of chain will you be using and how will you take up the chain slack as the chain wears.

windy

[fabricator]

It's #50 chain, in an oil bath, I've seen many chain drives open to the weather last for years with little or no lube, I'm 51 now so I'm thinkin I'll be dead for 20 years before this chain even shows signs of wear, I plan on living to be 120.

[zvizdic]

My concern is a high Amps and loses .
You should see over 200A at 24v (28.8V)  in high winds .

[Watt]

Is it 16-17' mill ?

If so you going to need a truck to haul all this Watts.

Yep 16' it's gonna use the RWS blades too, it's prolly gonna be a handful until I learn how to handle it, but fortunately Chris has a new wrinkle on that end too, but that's a whole nuther ball of wax for him to explain sometime maybe.

Very nice for sure.  Just an off topic question    I've tried in vain to get those RWS blades and can't seem to find a working website for them.  Any chance you could post or pm contact information for them?  I tried one of the links Chris posted but I get an error loading page once clicked.  Thank you sir.  Mike

[Flux]

I am sure you are right to use a chain rather than gears. I built several geared machines with wound field alternators and the gears were nothing but trouble.

I came to the conclusion that the only gears that would stand up for any length of time had to be hardened. I used off the shelf hobbed gears that should have been big enough to eat the job but they just didn't stand up to the loading. After a few years I had to turn the wheels round and run on the other tooth face, that shut the noise up for a while but the things were so noisy at the end that it was a pleasure to replace them with a quiet direct drive.

I also found timing belts very ineffective and again they had to be rated for about 3 times the expected peak load or they would snap or strip teeth.

Nice work.

Flux

[ghurd]

Looks like a lot of time and precision work in that one!

Anybody have any idea WHY "that {#13}coil got warm to the touch" when it was unloaded?
Must have been a lot of eddy currents?  Or a shorted coil?
Even at that kind of speed, seems like unloaded nonencapsulated #13 should not get warm?
G-

[Flux]

If my conversion is right, #13 is near 2mm diameter, that must be approaching the limit for wire diameter at that sort of speed.
It's thicker than anything I would use.

That is one of the snags of gearing, it lets you use much thicker wire with few turns but the thing has to be wound with parallel strands of thinner wire to avoid eddy currents. It is back to the problems of building big 12v alternators, few turns and lots of parallel circuits.

Having gone to the trouble of building the speed increase I would over build the alternator as that will be a small part of the cost. I would keep the efficiency up too high for the intended blades so that it would stall hard, then add the needed loss in the line or an external resistor. That way the stator can run very cool. That's the best way with any alternator but it becomes too costly with direct drive once you get over about 10ft diameter blades.

Flux

[gsw999]

Thats pretty cool, please keep us posted.

Gav

[ChrisOlson]

Anybody have any idea WHY "that {#13}coil got warm to the touch" when it was unloaded?

Eddy currents from the generator spinning at 2,000 rpm.  In actual operation on the tower the generator speed will be very close to my geared machines - around 800-850 rpm tops.  At that speed AWG 13 wired delta will be fine.  I found during testing these geared generators that 1,000 rpm is about the top end before you start to get stator heating from eddy currents in big winding wire.  A wye stator runs just sizzling hot at that speed because you're running power thru two coil groups along with the eddy problems.  Delta runs nice and cool with the parallel'd coil groups.

This machine that Fab is building is going to be capable of some downright scary amps in higher winds.  But where they really perform is in the 12-15 mph wind speed range and the trick is to limit power output at the high end to prevent burning all you stuff up.  Like I found out with my 12G machines, building for top end power will make 3/8" bolts used for fuses glow red hot.  They're designed and built for the mid-range where most people's wind blows 90% of the time.  Using the lower rpm, torquey GOE222 blade profile with the geared generator running at around 500 rpm delivers very impressive, constant amp-rate power at 12-15 mph that no direct-drive machine I've ever flown can match.  It's nothing to see 10-12 kWh in a day out of my 12 footers in a decent breeze and I think Dale's machine will take that up a notch.  The trick will be power limiting it when the ampacity of the wiring is reached.  We're in this for kWh/day, day in and day out, not Big Wind Bragging Amps.
--
Chris

[GoVertical]

That is one of the snags of gearing, it lets you use much thicker wire with few turns but the thing has to be wound with parallel strands of thinner wire to avoid eddy currents. It is back to the problems of building big 12v alternators, few turns and lots of parallel circuits.


Flux

Greeting, where do the Eddy Currents form?

[Flux]

The eddies come from circulating currents within the thick copper. It is the same effect as an eddy current brake.

For conventional alternators with the wire wound in slots in an iron core the effect doesn't show under normal conditions as the flux doesn't directly cut the copper, it snaps from tooth to tooth and the emf is generated by this linking flux.

With machines with no iron the copper section directly cuts the magnetic field and the flux enters the coil progressively turn by turn. This is no problem with high voltage machines wound with thin wire but it does present challenges when you are trying to deal with currents beyond the capability of wires near 2mm thick.

Using two starands of half csa wire helps raise the limit a lot. In extreme cases you need lots of strands in hand and you need to take care that each strand links the same flux or there will be circulating currents within the individual parallel strands. For very high currents you have to transpose the strands that make up the conductor bar to equalise the individual strand voltages.

Nothing new, it was understood long ago when air gap alternators were tried but it got forgotten with the slotted cores taking over the main machine production about 1900.

Flux

[ChrisOlson]

Greeting, where do the Eddy Currents form?

Flux explained it pretty well.  From a practical standpoint, there's limits to how big the wire is you can wind with, how fast you drag the flux over the copper mass in the coils and how big your poles are in a air core generator.  It's like dragging a big neo across a piece of aluminum.  If you move it over the aluminum very slow you won't feel any "drag" and no heat is generated due to an opposing magnetic field in the aluminum.  Drag it across it fast and now you get drag and heat.

In these generators, 2,000 rpm is way too fast with 13 AWG wire.  Anything below 1,000 rpm is fine with the 2 x 1 x .5 N42 neos used here.

I built one delta 12 volt generator using AWG 12 and that also worked fine at 800 rpm.  Using the same AWG 12 wire in wye with number of turns divided by 1.732 for the star connection end up with a stator that ran just sizzling hot.  I attributed this to the fact that with the coil groups connected in series there must be a "buildup" of resistance to current flow caused by the eddy current that generates a lot heat.  With the delta connection the problem went away, as you have basically two coil groups feeding one "leg" in parallel, reducing the total length of the copper that the total current has to pass thru.

Modified post to add a note:  The wye stator was wound two-in hand, the delta was wound with a single strand of 12 AWG.

These neo magnets are too powerful for geared generators, in all reality.  It takes a careful balance of components to get the desired results.  A wound field with a laminated steel core stator would be ideal and that's one of the projects I'm working on at present.
--
Chris

[Flux]

The big snag with wound field machines is that you loose all the power needed to excite the field. For your wind area I don't see this as a big issue as you don't rely much on winds under 10mph.

The nice thing about the wound field is that you can match the load just by controlling the field current. This is really getting back where I started long before the days of neo. Not very practical for direct drive but things change when you can get the speed up. Lots of learning on the way to get the best results but possible.

Flux

[ChrisOlson]

The nice thing about the wound field is that you can match the load just by controlling the field current. This is really getting back where I started long before the days of neo. Not very practical for direct drive but things change when you can get the speed up. Lots of learning on the way to get the best results but possible.

Indeed - it's a big learning curve and a lot of experimenting.  The first one I built with the field wound with AWG 24 will cut in at 230 generator rpm with .13 amps of field current @ 24 volt DC.  The field is drawing 4 watts with losses in the copper, while the generator is delivering only 5 watts, for a net 1 watt of output at cut-in.  With neos on the same stator it delivers 8 watts at 230 rpm.

Once you get to 300 rpm, then the wound field catches up.  I'm still experimenting with it but I'll get it figured out eventually.
--
Chris

[halfcrazy]

Does any body now where Royal Wind and Solar's website went? I went looking for info and it is gone

[ChrisOlson]

Does any body now where Royal Wind and Solar's website went? I went looking for info and it is gone

http://royalwindandsolar.com/

--
Chris

[SparWeb]

Fabricator,
Watched your video.
Seems your cat "ain't scared of nuttin" either!

[ChrisOlson]

Seems your cat "ain't scared of nuttin" either!

You notice that cat was watching from a safe location until the explosion hazard was over and he heard stuff spooling down.
--
Chris

[fabricator]

I am sure you are right to use a chain rather than gears. I built several geared machines with wound field alternators and the gears were nothing but trouble.

I came to the conclusion that the only gears that would stand up for any length of time had to be hardened. I used off the shelf hobbed gears that should have been big enough to eat the job but they just didn't stand up to the loading. After a few years I had to turn the wheels round and run on the other tooth face, that shut the noise up for a while but the things were so noisy at the end that it was a pleasure to replace them with a quiet direct drive.

I also found timing belts very ineffective and again they had to be rated for about 3 times the expected peak load or they would snap or strip teeth.

Nice work.

Flux

That is the problem with gears is everything has to be perfect, with chain and sprockets you have some wiggle room, if you were running for a few years on gears, you had to have had a high level of precision going, I wouldn't even want to try it, I'm not that good 

[fabricator]

Well, the laser at work did a lot of precision work, I drew it out, they fed it to the machine and I did a lot of tig welding, the precision of that thing is incredible, I told it I wanted .201 hole to tap 1/4-20 threads and they came out right on the dot .201.

[fabricator]

Fabricator,
Watched your video.
Seems your cat "ain't scared of nuttin" either!

That cat is a piece of work, it just showed up here one day, I think somebody dropped it off, it's a no maintenance pet, it's a tough as nails tom cat, I keep some dry cat food in a spot where it can get at it but it don't eat much of it.
When it showed up during the video that was the first time I'd seen it in about a week, sometimes it comes back all beat up, then it'll lay low for a week or so and heal up and go right back in the game.