Update: DIY Amp Hour meter for monitoring charge!

All about homebrew wind and offgrid power systems, the complete reference!

**Signing Up**

## Step 1: Build the magnet disks

## Step 2: Build the coil disk

more details, see the following page 15 for the series star, 1-y diagram.

http://groups.yahoo.com/neo/groups/axialflux/files

AXIAL_FLUX_HowItWorks.pdf

## Step 3: Build the bearing assembly

## Step 4: Construct the blades

More can be found at

http://tech.groups.yahoo.com/group/axialflux/

http://www.green-trust.org

http://youtube.com/watch?v=o9EEHFKEckM

1000W / 12V = 83.3A

from any of the ampacity tables i could find online 83 Amps would need arround AWG 4 for enclosed wire and AWG 7 for open air application. Am I missing something? Please explain.

You say here that doubling the number of turns of wire doubles to voltage output, right? Do you know what effect more magnets would have? Would doubling the number of magnets (and the number of coils), but keeping it at 35 turns double the number of watts output without doubling the volts?

Also, do you know how many rpm you'd need to get out of this thing for it to actually reach 1000W?

I am building a vertical turbine with a savonius (starter) inner rotor and a larger H type main rotor on the same shaft. With this setup in low wind, below startup, the turbine will still be turning and by connecting the rectifiers in series I could get usefull voltage at low current. When the winds pick up the rectifiers will be switched back to parallel so the main rotor can kick in.

Is this possible, or is there some reason 3 phase is only wired in star or delta?

The ac voltage is determined by the number of turns in the coils, and the wind speed vs. load. If the voltage is too low, the batteries do not charge.

you can get current directly from ALL the coils all at once !

What is the separation between the coil and the magnet face? I didn't see a stat on the field spread. I did note that the magnet has a 175 F max temp before damage and I have visions of a 100F plus day with the turbine cranking. How do the magnets stay "cooler" along with the coils themselves during power production?

Can i make thins thing with hard disk megnets because im unable to buy this shape and neodymium magnet. from my place. so i think hard disk magnets are neodymium magnets and they can be use for this procedure ? Can it be ?

i have 200 pieces so i can use them together/

I am planning to use only 6 coils with about 300 turns and rectifying every single coil and then put then in series or parallel depending on the wind. 6 Magnet pieces together X 8 around each disk.

Does it make sense? Is there any problem rectifying each coil?

Also, I used some resin they use on cars that seams to interact with the magnet. I will find where to get this epox instead.

Thanks in advance

- Interact meaning it pulls or push the magnet, acting like one. I will look for other resin kind. When I say putting them into series, it would be after rectifying them (2 diodes per coil + capacitor).

- My concern on making it into phase is that since I have different magnets sizes I would not know how to perfectly mach the disposition of the coils X magnets. I did see on your pdf the ratio would be 1/1.333 though, but I just wanted to keep it simple to avoid more frustration. :)

Extra info: The magnets I got are 20mm diameter x 12mm height. 8 per disk. (Total 16 magnets blocks)

Each coil: 300 turns x 22awg = 40mm diameter. (Total 6 coils)

Hey, I really appreciate all your attention and help.

the applications of this design are wide open!

2 of these -sans the blades...could easily gen a bunch -o-power on say,...a stationary bike...or heck a small lawnmower engine could spin a row of these ...make for Da' BomB camping gen

Thanks for sharin' yer info bro!

I have to go with the latter since you left out allot of build information.

The cost from doing this "project" cost vs. power output is far more than what I did.

I went to a junkyard found a 260 amp alternator ( $100)off an ambulance and mounted and attached a wind prop to it. I pulled the voltage regulator and used a Sevcon unit for control. I used #4 welding cable with soldiered terminals to take the alt. output directly from the rectifiers. For charging the batteries using a HF ( high Freq. battery charger is best ). There is more electronics for the out put to the house etc..

You can also use the motor from a treadmill; you see them all the time on someone's curb they are throwing out...

I included some math about windturbines:

Power AVAILABLE in the wind = .5 x air density x swept area x (wind velocity cubed)

Example: air density = 1.23 kg per cubic meter at sea level. Swept area = pi x r squared. Our 2 foot blades = 0.609m, 4 ft = 1.219m. 10 mph = 4.4704 m/s, 20 mph = 8.9408 m/s.

How much power is in the wind: 2 ft blade, 10 mph winds = .5 x 1.23 x 3.14 x 0.609squared x 4.4704 cubed

= .5 x 1.23 x 1.159 x 89.338 = 63.7 watts

With 4 foot blades and 10 mph winds = .5 x 1.23 x 4.666 x 89.338 = 256 watts

With 4 foot blades and 20 mph winds = .5 x 1.23 x 4.666 x 714.708 = 2051 watts

That's the MAXIMUM power in the wind. However, it's impossible to harvest ALL the power. The Betz Limit tells us that the maximum percentage of power we can harvest from the wind is 59.26%.

Thus our maximum power from these turbines would be:

2 ft blades, 10 mph wind = 37.7 watts

4 ft blades, 10 mph wind = 152 watts

4 ft blades, 20 mph wind = 1,215 watts

In parting even the motor from a direct drive washing machine can and is used for a wind generator; the design is very similar to what you show everyone in your posting. All I am trying to comment about is allot of people may not have the time or ability to duplicated what you did.