Sawblade windmill up and running for one month now

[margusten]

Hi everybody,

My sawblade windmill idea:

http://www.fieldlines.com/story/2006/5/30/122744/161

Now it's up and running good.

Starting to spin with lightest of wing gust.

Spinning allmost freely, because inside sawblade with permanent magnets from old hard disks. Stator is made of plywood and epoxy without metal parts.





Only drawback is small current. Next time I am going to use thick wire.

Stator is made of 2 phases and planned to connect parallel. In reality they are connected series to start charging battery with slightest wind. In parallel they can make 4A as planned.

Pictute of this sawblade windmill:

No real tower yet, only test stand.

Carwing blades was harder then I thought.

They are 1,5 m diametre. Spinning wery good and are allmost silent.

Cable from this windmill comes to my garage, where battery's are located. Cable is doubled to achieve smaller resistance.

You can see all my current working windmills from this picture:

In the middle is windmill made of geared stepper motor from ancient network printer.

Blades made from PVC tube and not so good.

This windmill can charge 12V battery with 0,5 .. 0,7A current.

More pictures coming in near future.

Margus

[hiker]

cool......

what neck of the woods do you live in??

is that just a single rotor set up--with no lams behind your coils??

check my files if you want on my sawblade mills.....

looks like you have a minny me windfarm there :}

[andyman5002]

Would it not be better to have some iron in there behind the mags and coils or use steel discs? Dont quote me on that but i thought I read somewhere it improves the flux or something? Anyway nice looking machine.

Andy

[margusten]

Yes, I have woods on west side (near 100 meters from my mills and about 18m tall spruce and pine trees), You can see shadows only from picture. East, East South and North side winds working great.

Yes it is single rotor and just plywood and epoxy behind coils. Figured out that metal sheet behind coils makes output bigger but increases cogging and needs much bigger starting windspeed. I learned this from my previous experiments. Ideal is double rotor but single rotor working too.

My goal is small windfarm up to 10KW, but starting from minny me windfarm.

Margus

[ghurd]

How deep are the magnets stacked?

"Next time I am going to use thick wire."

Most people would suggest 9 coils and 3 phase for more output.

It can use the same magnet rotor.

G-

[electrondady1]

<BR good work margus
i like the way you used the different size magnets
did you use a wave form winding stator?
if you can rotate a second saw blade (even with no magnets on it)  it won't cog and would increase power.
three phase is cool but on a small mill it might be difficult to reach charging voltage.

[margusten]

Hi,

Cilinder shape magnets are diametre 14x8mm deep. Other magnets from computer harddiscs.

Failed with first stator - uncommon type. Check my old diary, about 5V 6A output. Then made one typical one phase stator 6x200 turns of 0,5 mm wire to get enough volts from small magnets.

There was no room for 3 phase. Then I decided that Volts are more important than Amperes. Now I know: most important are big magnets.

Margus

[margusten]

Yes my coils and magnets have same shape.

I practised before with magnets and coils from computer hard disks. You can find one usable coil as well from every computer hard disk. Unfortunately wire is too thin and I reached only 0,3A. Never thought about rotating second disc. Only glued coils to second disc.

Please check my files to see 2 videos I made.

Seems no good to put videos here like pictures.

Margus