Question about Voltage of a Turbine.

[theiceman]

Hello, thank you for reading my post. I know this is way too basic but I steel need help.

Depending on the stator you made, you get an specific voltage like 12V Every Time at a every speed?, I mean, once it cuts in you start receiving 12V constantly regardless of wind speed and the only thing that varies is AMPS? Is that the way it works?

Also, if for instance, I made an stator and it doesn't give me 12V or 24V but and Odd amount like 15V, what do you do then, can you still use that and convert it to 12V or that stator just needs to be redone in order to get 12V or 24V.

Is there any formula to get the exact 12V or 24V by increasing or decreasing the number of turns in the coils and the wire size that works for every machine, and if so what is it.

Does this work like that: Suppose I have a machine with 6 coils and I want 12V, does it mean that every coil has to give me 2Volts, and I can use a test coil and place it provisionally and turn the machine and adapt the number of turns to finally get the 2 volts so it serves as a model to wind the other coils and get the 2Volts x 6 Coils = 12V configuration.

Thank you very much for your patience with this newbie.

[Flux]

No it doesn't work like that but you can be excused for thinking it does.

Voltage depends on speed and you will see that directly up to cut in point.

When the generator dc volts exceeds the battery volts the battery will clamp its terminal voltage to nominal value ( depends on state of charge). The battery voltage will change little.

What really happens is that the generated emf ( internal and you can't get at it) still rises with speed but the battery clamps the terminal volts. The difference between emf and terminal volts forces a current through the windings and battery in accordance with Ohm's Law, through the winding and circuit resistance. What you see above cut in is a fairly constant terminal voltage and a current rising with generator ( wind ) speed.

System voltage is an arbitrary thing really. It is that voltage that you choose to use to get the cut in speed in the wind you want.

If you ended up with 15v, then it would cut in slightly slower on 12v and it would work fine. You may be able to use it at 24v but it would take more wind to reach the higher cut in speed.

This is too complicated to explain to a beginner but I hope you get some idea from it.

Flux

[theiceman]

Thank you very much for your explanation. It was of alot of help. I have another question, suppose I want to check what is my Generators Voltage, to see if its going to work for a 12V battery arrange for instance, what should I do to check that with a Voltimeter. I should turn it and see the readings, but at how many RPM will I get the Volts Lecture that is The Voltage of the Machine?

Thank you again for your patiente.

[Flux]

Here again it is difficult to answer in a way that a beginner can understand.

If you know what speed your prop will do in a certain wind speed then it is reasonably easy.

Say you want to cut in in a reasonably low wind ( 7 mph) and you know your blades will do 100 rpm with no load at this speed then all you need is an alternator that will produce nominal battery voltage ( 12, 24 or whatever you choose) at 100 rpm.

If you haven't settled the blade issue or anything else then you are not in a good position to go anywhere. Power out and speed is related to prop size and wind speed and the whole lot interacts.

You have to end up with a cut in to suit your blades and an alternator with a power characteristic that matches the chosen blades.

Copy one of Dan's designs that work Or buy Hugh Piggott's book and you will get there first time. Do as most do and you have a long learning curve and probably loose interest before you see something that works.

Flux

[theiceman]

thanks for all your help man.