stator help requrired

[zoo1]

Hello everyone!
I am worry about my wind turbine. The story begins since 2009. I search a lot about the wind turbine and finally got this board. I really appreciate the owner of this board by my heart.
Now comeback to the topic, first I made my stator with #26 wire with 260 turns with a test coil and make 9 coils 3 phase with star configuration and used N42 2in 1in and 1/4in with single rotor, got 25volt (with out load) dc with high rpm with my hand but when I connect this with battery and turn the rotor with my hand it get's too hard to spun.

Then I think to make an other stator with #14 wire with 55 turns with one coil but I got 0.2 ac volts (why it's out of my range).

After this I went and purchase #21 and wind a test coil with 155 turns and got 1.5 ac volts. It's good for me I made the stator with same configuration as earlier. I spun with my hand with battery load it's hardly reach the 12 volt dc. Without load it gave me 14 volt dc. In other words it is also useless.

Now I wind a test coil with #18 wire with 130 turns and got 1volt ac at 60 rpm. (with same single rotor). I don't think that I will met the success even with this.

Please do something for me to improve this


After a long trouble I think to share this bad experience with all of you on this board. Because I know that here are great personalities that work for other's and share their knowledge with other's and solve problems.



Please give the answer of following questions

1: What's wrong with my first stator?

2: Why I got 0.2 volts ac with #14 wire?

3: I want to reduce rpm and want to make at least 500 watts turbine. Spin it with my hand until I recharge the 12v battery.

[Flux]

"3: I want to reduce rpm and want to make at least 500 watts turbine. Spin it with my hand until I recharge the 12v battery."

If you really mean this then you are in for a disappointment.

You will struggle to hand crank an alternator to 300rpm, you will never sustain that speed. with a decent crank you may manage 120rpm or a bit more comfortably.

Even if the alternator is 100% efficient you will not manage to hand crank much over 150W for any length of time.

For a very low speed alternator to be reasonably efficient you need lots of magnet and copper. With your tiny magnets on a single rotor and the thin wire you are not going to see any decent efficiency even at 150W out.

There are probably nothing really wrong with your coils. For small magnets, a very inefficient single rotor magnet system and very low speed you are probably getting things near right. if you were to use the thicker wires with less turns and run it at a sensible speed you could possibly get in the hundreds of Watts.

Even a small wind turbine makes a fair bit of power in decent winds. To get 500W out you will need to put in significantly over 1hp. Man can not sustain 1/10hp for any significant time without lots of training and using hands and feet.

It takes energy mechanically to produce electrical energy out, it will always become too hard to turn once you get in the 200W region.

If your only source of power is human power then you need to make the most efficient alternator you can, it will be big and costly unless you use a chain drive and increase the speed. the single rotor approach is not even worth considering if you want it cost effective.

Flux

[zoo1]

Dear flux!
It is not possible for me to buy thicker magnets I got these magnets after a long time search and  get very costly 10,000 rupees. i also tried to get them form USA but all in vain. They said it the shipping charges is more than $100.
Therefore I want to manage my alternator to increase the magnet wire.
 
What should I can do with my this turbine of #21 wire with 150 turns on each coil.
I already told you that there is exact 12 volt DC when connected to the battery at high rpm with my hand.

Can you suggest me some kind of improvement which let me charge my 12 volt battery even for a limited time.

[Flux]

Can you explain a bit more, from your previous post I thought you were trying to hand crank the alternator to charge a battery, I didn't get the impression you were building it for a turbine.

Give me some idea of the size of the turbine you intend to use and I may be able to to help you more. You may not get your 500W but I am sure you could get something worthwhile. Your experiments so far are possibly nearer that you think, I think you have been held back by the fact that you can't hand crank the thing on load and you have been trying to reach the 12v dc at too low a speed.

Flux

[XXLRay]

It is absolutely normal that voltage drops when connected to a battery. When charging a battery directly by a generator the current ins kind of "self-regulating" and will increase along with increasing battery voltage.

Could you please clarify whether you really plan to crank your generator by hand? I am very sure that your body will not be able to put 500W into the generator for more than seconds.

It would be very helpful to attach a rpm-meter to your generator. You can easily build one from a cheap digital bicycle  tachometer. Furthermore you should measure current when testing the generator under load.

[jlt]

You can almost double Your  Voltage by adding a second blank rotor. With only 1/4 inch mags you will have to keep stator as thin as possible.     

[ghurd]

With only 1/4 inch mags you will have to keep stator as thin as possible.     

I was wondering how many of the 55 turns of #14 were close enough to do any good.  Sounds like pretty large coils to get  a large percentage close enough to 1/4" thick magnets.
G-

[Flux]

I am pretty sure that the coils will be too thick, especially the thicker sizes of wire.

Without any idea of the speed aimed for it is not useful to comment much on the coils at this stage. At the most the coils won't need to be thicker than 6mm and it would help a great deal with a second steel disc spinning with the magnet disc. Even with this additional benefit the thin magnets are going to be a problem unless the mechanics is very good and the discs run very true..

In the end the local wind speed will be a big factor. High speed will be a great start in overcoming the magnet limitations, too large a prop will limit the speed so I suspect something under 5ft diameter and if it is a really good wind area several hundred watts might be possible. with low speed pvc blades then 100W would be quite a challenge.