# wind turbine project

#### davez

Oct 11, 2014
27
I am planning to create a wind turbine that will be able to charge phones i need help in finding a good dc motor
will a 12v 25w dc motor with 3500rpm be able to create enough voltage to charge the phone?
Here are the materials that I have for the project:
*blocking diode
*Electrolytic Capacitor 2200uF
*12v/6v rechargeable battery (lithium)

note Im asking you guys to help me if the motor will be ok for the project if not please help me find a good one
thank you and God Bless

#### duke37

Jan 9, 2011
5,364
The 12V permanent magnet motor will produce 12V at 3500rpm. Can you spin it that fast? you could use it at a lower speed and boost the voltage. You can get circuits which will take varying voltages and output a constant voltage.

#### davez

Oct 11, 2014
27
so if i will be able to find a motor with lower rpm will that be ok?

Oct 11, 2014
27

#### Merlin3189

Aug 4, 2011
250
Permanent magnet motor voltage output is proportional to speed. So if it gives 12V at 3500 rpm, it should give 6V at 1750rpm. So you don't have to use one just at its rated speed.

Your problem is getting a wind turbine to turn something efficiently at any speed - unless you are planning to run it next to a fan! You want a motor with low friction, but not too heavy. The electrical side is not a big problem. Design is well known & understood. Turbines (fans, propellors, etc.) are much more difficult.

Yes, if you can find a motor that is designed to run at low speed and high voltage, that saves you converting the output. It will give lower current, but you are looking at a fairly low current application here. The question is how fast is your turbine going to run? Then, other things being equal, you want a motor that gives the voltage you need at that speed.

Maybe, build a turbine and measure its speed & torque characteristics. That will tell you what power you can get from it and so what generator you want. If you can't get one suitable, it's not a big problem. As Duke says, you can convert voltages without too much inefficiency.

Just checking back with your first post, I see you have this motor. So you need to see how fast you can turn it and that will tell you the max voltage you can get. Of course it will slow down a bit when you connect the circuit, so you need a bit of leeway.

#### duke37

Jan 9, 2011
5,364
I have never played with stepper motors but they may be suitable. They have no brushes so will be low friction, they may however have significant cogging where considerable torque would be needed to start. They would produce AC so would need the two windings rectified before combining.

#### davez

Oct 11, 2014
27
im still searching for a suitable a motor but thanks for the info i will try to find a low rpm motor

#### davez

Oct 11, 2014
27
hey guys i have bought a dc servo motor will this be ok..its manufacturer is yaksawa?

#### BobK

Jan 5, 2010
7,682
That is an interesting choice. Can you link to the motor you bought?

Bob

Oct 11, 2014
27

Jan 5, 2010
7,682

#### Merlin3189

Aug 4, 2011
250
And it is a stepper motor?
It looks like a DC servo motor. If it is, it would be no better than an ordinary DC motor and might have more friction due to the servo element.

Replies
5
Views
917
Replies
0
Views
1K
Replies
33
Views
3K
Replies
17
Views
9K
Replies
7
Views
616