Wind turbine Savonious Charger based on Joule Thief - advise for a charger?

[falexandru]

"This site can't be reached
%22's server IP address could not be found."

When I go to the "insert image" the only window I see is the one for the URL. Nothing else.

I am on Windows7 64b.

[ReverseEMF]

"This site can't be reached
%22's server IP address could not be found."

When I go to the "insert image" the only window I see is the one for the URL. Nothing else.

I am on Windows7 64b.

Yup.  I caught that, but obviously not quick enough   Try the link again, it should be working, now.

[falexandru]

I am trying again.



I have no idea why it did not work first time. Just do not understand.

[allanhurst]

For the Savonius I  only have a concept at this time.

The most important device here is likely to be the generator. Using an off-the shelf cheap dc motor is unlikely to be the best solution.

Consider winding your own pm alternator?

Until you know what your generator produces, discussion of various possible power conditioning techniques is academic at best.


Alan

[mauried]

Have you actually built the wind turbine ?
Savonius rotors are very inefficient, and if you are trying to generate anything at very low wind speeds, the type of generator is most important, as it requires extremely low rotational friction.
Id start by building the turbine first, and then worry about getting useful power from it.

[falexandru]

This is a demo project.

Any little power is sufficient.

If nothing else works, then I will use a fan to move the Savonius rotor (I must do this indoor anyway). Or even blowing on it. :-)).   

[falexandru]

Note about my post #17:  Uploading the picture to show up within the text did not work first time. 

I did not experiment the posted circuit in post #17. 

[ReverseEMF]

Note about my post #17:  Uploading the picture to show up within the text did not work first time.  

I did not experiment the posted circuit in post #17.  

Do you mean post #18?  If you are referring to the diagram in that post, it's the "classic" Joule Thief circuit.  It's pretty easy to get that working.  But, it's critical to get the coil hooked up correctly.  I suggest adding a capacitor across the generator [following the power switch].  The value will depend on what kind of power is involved.  Such a capacitor will make it more likely that charge will accumulate and run the stored voltage up until the Joule Thief starts to oscillate.  Then, it will transfer power from the capacitor, to the battery.  But, as pointed out before, this will only be feasible for a low power system.  But, it sounds like that's what you are after -- merely a demonstration of principle.

[falexandru]

@reversEMF - right!

I only want to show that this way of obtaining energy is feasible using basic resources, it is easy to make, easy to maintain.

[maybe  OT: so many times I saw projects (including my projects :-)) never getting to an end because of to ambitious goals. It is crystal clear in my mind that Arduino is about learning and teaching in the first place. Of course, real life projects can be done in the Arduino ecosystem (or alike), but myself I am not in this.]

Thank you for the reccomandation! It is possible to use a trimer (aka variable capacitor) for the capacitor you suggested? If so, what value do you think? 

I can find here easy a 4-20 pF and a 7-100 pF.

The 7-100 pF has a larger range so might be handy. Then I can go (hopefully :-) ) by trial and error.

The coil- yeah, I have a bunch of torroids and drossels on my desk. I cant measure them by my multimeters and honestly the devices to measure capacitance and inductance are insanely expensive.

[ReverseEMF]

Please the "Quote" feature.  Otherwise, it's hard to track context when reading your posts.

[falexandru]

@ ReverseEMF - you are right!

But so far, I couldnt figure out how to quote part of the text. Quote command is picking all text, making everything even more difficult to read. I attempted to delete unwanted text or to manually quote, but the result was even more fuzzy :-(.
I will be very happy if somebody can point me to a tutorial or just tell me how to do.

++++

This is my lucky thread - I already figured out how to insert images in the text! :-))

[TomGeorge]

Hi,
If you look at the tool bar across the top of the post/edit window, you will find an icon that shows "Insert a quote"
This inserts quote tags around a highlighted bit of text in your post window.

So copy and paste what you want in your post, then highlght it, then select "Remove Formatting" in the tool box, the "Ao" icon.
Then select "Insert a Quote".
You will then have your tect in a quote box.

It is worthwhile using "Remove Formatting" to take out any artifacts that the editor may misinterpret.

http://forum.arduino.cc/index.php/topic,148850.0.html
is a good read.

Tom...

[falexandru]

@TomGeorge

So copy and paste what you want in your post, then highlght it, then select "Remove Formatting" in the tool box, the "Ao" icon.
Then select "Insert a Quote"

Thank you!

My mistake was:  I selected and quoted the text directly in the quoted text, in the author's post.

PS It is any way to also automatically quote the quoted author in the same time? Thanks!

[ReverseEMF]

PS It is any way to also automatically quote the quoted author in the same time? Thanks!

Try this:

• Click on Quote [on any post -- just so you get an editing session with a automatic Quote field -- for instance, click Quote on this post]
• Way at the right end of the tool bar, there is an icon that looks like a little page of text -- it also looks grayed out but don't believe it.  Click on it and it will change the editor contents into the raw text with BBCode showing.
• Find the BBCode for the Quoted area. Use that as a quide. You can leave out everything but the author=forum_username attribute

[falexandru]

Perhaps is not exactly the right place to rise this up, but I hope I will be forgiven.

There is very little - if any - info about vertical axis turbines in a manner that is appropriate for demo or diy aim.

I noticed so far two main issues with vertical axis wind turbines:

a) the available voltage is going to be far less than one of a PV panel, at a similar phisical magnitude

Perhaps this comes from the PV being industrially manufactured while turbines have to be made from scratch in most dit cases => this leads me to the idea to use a "buffer" - like a super-capacitor and then periodically discharge it through the Joule thief circuit, but under higher voltage - that is something I never saw in the internet and I would be very glad to get your opinion


b) There is a dependence of the Joule circuit to the way the inductance is made or mounted. I have no idea how to approach this, except by trial and error - any tip or no-matter-how-personal opinion would be of great help.


For the time being I am working on the PV module, but I will finish very soon and start the fight with the electronic part of this wind turbine.

The plan is to use an (close to) exhausted 1.5 V AA Alkaline pile in place of the wind turbine while desk prototyping. Alternatively, I can mount a voltage divider to the NiMH 3 or 1 units that I already coupled to the PV generator.