El Cheapo Lenz 2 Clone

[coldte]

I wish to thank all who read the previous posting and further update on progress and ask assistance for some problems i am having(grey matter thinning out).Well as previously stated i have some success especially using the plastic containers , in fact they are very impresive in performance ,  i made two sets from one barrel but had one set at 18 inch diameter and the other at 3ft 6inches , both run in the slightest breeze without an, alternator connected. with the rotors assembled there is no delay at all in the large one and only a small amount in the smaller diameter(seem to have hit on something)The alternator i have ended up running mainly for test purposes is 8-pole and 6 coils, magnets 40 *20 *10,coils 300 turns 0.65mm,neither one potted at the moment.

Output seems to be a bit low(hence help required or thinking changed) i was hoping to achieve around 12 volts  at 100 to 120 rpm and itis not achieving this until 150 then from there it shoots up rapidly,highest so far 27 volts at about 230+. what i require is some assistance in aiming my thoughts in the correct direction to achieve this.

It may be of interest to note that in the same wind speed the rotors behave very different ,Large one appears to be self regulating and is in fact a pleasure to watch( sad) the smaller is almost twice as fast.

If any one can assist in getting the output of the large rotor up please feel free to chip in .thats all for now ,i have a few o0ther things on the go and will add as and when.

Coldte

[tecker]

  The bldes are reversed .How's the torque with that orientation ? Very neat

[tecker]

yoops I didn't look closely they are the right orientation .

[coldte]

when the blades are spinning at about 80-120 the torque is quite good on the large rotor,but less on smaller version which takes a tad more wind to get started,but spins up very fast. As stated before i personally prefer the large rotor but am not sure how to adjust to get the results i require ,eg 12-15 volts about 2 amps at around 100-120 rpm.

regards

coldte

[Lumberjack]

The larger blades and larger diameter normally will run slower and give more torque. Normal.

[tecker]

Jerry phase your stator for a better cutin ( flux has a good drawing for that In his files) . Or put a pickup on the rotor to pulse with the  highest voltage you can get use a 40 ohm or higher solenoid coil to   crowbar  four or more 5000 uf 50 volt caps ( cheap enough ) into your batteries .

[tecker]

That's make apickup out of the soleniod and use 2n3055 or a 2n5885 one series to two parallel good heatsinks

[coldte]

thankyou for your reply ,but being new to this game it was a little over my head could you please send further info/and or expand on what you suggested  i am willing to try anything (within reason) once .thanks again

coldte

[tecker]

No prob here's the link to a jerry phase clear drawing just connect each phases to it's own bridge and add series the dc out to get a losw cut . The Crowbar I'll draw out or take some pictures .

http://www.otherpower.com/images/scimages/1671/starJerry.gif

[fungus]

Looking very nice there - what did you use for a hub/bearings?

Also where are you located?

[tecker]

If the mill stalls with your battery set  pulsing the batteries is a good way to get  what you need . Say 6 to 10 volts dc from each phase you should be in the house with a series connection . Around 100 rpm under load is top end for a vawt like that . Try to jerry it if that dosen't work you can follow up with the pulser which should work with both mills.

[coldte]

Thankyou for your interest,the hubs are standard trailer hubs about 30 pounds a pair.As to location i live in sunny lincolnshire and have done for over 25 years. regards

coldte

[electrondady1]

congratulations. the mills look good.

you stated on your first post that you had 12 coils and 12 mags

this is a single phase ratio.

the advise you have received for "jerry rigging " is useless to you as you do not have multiple phases.

are the alternators both the same?

that is to say, a total of 12 magnets on each

are they a dual rotor or single

[tecker]

 He wrote up 8 x 6 with 300 turns per coil

[electrondady1]

it looks as though you are using a single rotor configuration.

a steel mag rotor for each alternator .

i cant tell does each rotor have 12 magnets?

[electrondady1]

sorry, i misunderstood.

[windstuffnow]

  I find it quite amazing, once an idea is set free on the internet, that so many ingenious - creative people will find ways of building them with what ever is available.  Nice job on your turbine!

  The speed at which it will run can be found using the following formula...  windspeed x 88 / ( diameter x 3.14 ) x .8 = rpm .  windspeed in mph diameter in feet.  As you can see the diameter plays a big part in the rpm.  

  A couple tips to get better performance from it.  First it looks like the leading edge is bolted on the outside of the blue plastic.  Outside or inside really doesn't matter.  What does matter is the edge it leaves... this will break up the air flowing across the wing creating eddy currents and reduce lift on the up wind side.  One of my original units made from PVC tube for the nose and aluminum sheet for the trailing edge had a very small edge.  After some testing it had occurred to me, from my aircraft building that this might be stealing some power.  I put a strip of tape from top to bottom and re-ran the tests.  I picked up almost 10 watts of power by simply smoothing out the edge.  This was only an edge of .025 inch thickness... the cleaner you make it the better it will run.

 Secondly, if you block the top and bottom of the open wings ( outward side )you will pick up more power.  The air tends to find an outlet, the ends in this case, which will reduce the ability of the wings to actually grab the air on the downwind side.  If you make them larger than the wing shape it will form a winglet, this will reduce the eddy currents around the top and bottom of the wings and hold the air on the wings farther in rotation which will give you a considerably longer power pulse on the upwind side.  

  Lastly, a little larger nose wouldn't hurt any either, extreme camber causes high lift in lower winds.  

  You can try a 3 phase voltage doubler on the existing alternator to get a lower cut in speed.  If you tap into the 3phase outputs before your existing rectifiers you'll get the best of both worlds.  Diagram below...

  Just a standard block rectifier and 2 capacitors that will handle the voltage.   I connected one to my turbine, leaving the main rectifiers in place and it went from 100 rpm cut in to 30 rpm cut in and starts charging in a 4mph wind - albeit very low charging, it's charging none the less. I set up a circuit to charge my small rechargeables from it as well, if it's turning - any at all - it's charging my ni-cads.  It actually does a little more than double.  Once the  voltage is up enough to pass the main rectifiers it doesn't seem to take away( or add )it's normal operation.

.

[coldte]

Thankyou for your reply,most informative . Must be honest your suggestion for adding flanges to top and btm of blades nearly came to fruition,I have a cruiser and this year after much research decided to add a NACA 18 rudder to improve slow speed maneuvering,it worked very well so it had crossed my mind but did not think it would transfer across to air,( will have to start going with instinct)the trailing edge of rudder is shaped like a fishes tail and seems to concentrate flow , it also has top and btm overhangs as you indicate, so like you have suggested might be worth a try. regards

coldte

[skipinder]

Hi tecker, just looked at the diagram, could you explain the red bits?