sorry everyone, but please understand me. I'm an electrical engineering student and we were ask to do a project proposal. and the project that came into my mind is that what if I use a pc fan as a generator to charge the battery of any kind of mobile phones. Is it possible to charge a mobile phone battery using a pc fan? If so, can everyone teach me how to do it. What are the things (components and material) that i need to use, and the circuit for it.,
I HOPE everyone understand me.,THANK YOU for helping!

 

Well, you could start by grabbing a PC fan, hooking up a voltmeter to the leads, spinning it with wind, your fingers, or and attached motor.

If you see 0V when it's not moving and >0V when it is, then you have the start of your generator.

You'll have to see the kind of voltage you get out of it (AC/DC), then determine if you need to "boost" the voltage or "buck" the voltage.

 

PC Fan → Full bridge rectifier → Capacitor filter → Power Regulator → 1N4001 → Battery

 

I am not sure a PC fan motor can be used as a generator. It has something to do with the construction of the motor. But the test in post #2 will give you the answer

 

I am not sure a PC fan motor can be used as a generator. It has something to do with the construction of the motor. But the test in post #2 will give you the answer

I was thinking the same thing. PC fans are usually brushless and relatively low current, with a controller circuit.
You might have some luck with a standard DC motor.

 

I am not sure a PC fan motor can be used as a generator. It has something to do with the construction of the motor. But the test in post #2 will give you the answer

It can be used, but the current is depends on the type of fan, if the current is too less, then the charging time will be a long Journey.

The problem is that if the blade of fan is too small then it will not easy to active the fan, and the power will too low.

 

I am not sure a PC fan motor can be used as a generator. It has something to do with the construction of the motor. But the test in post #2 will give you the answer

I have not tried a fan yet but I have tried a floppy disk motor. The motor will produce a fairly insignificant amount of voltage. If I remember not more than a volt or too.

I would think that the construction of the fan blades and rotor mechanism would not make it conducive to converting wind energy to electrical energy anyway. Most fans are fairly hard to move. The pitch of the blades is designed to move air and not convert air to mechanical energy.

 

Some PC fan motors are ruined when the blades are turned with moving air.

 

The electronic components on the board inside the fan have to be removed/ignored in the circuitry to obtain some voltage by tapping the windings only and bringing with wires the generation outside. Then a high impedance or resistance circuit can evaluate wind speed.

 

Thank you everyone for helping me. I used to test my pc fan generator by lighting up an LED in PARALLEL and I ended in lighting 8 super bright LED. I search for the specs of led and I read that in order for the LED to light it needs 20mA. Then I calculated it...
(20mA x 8 LED) = 0.16A.,is my calculation right?

 

LEDs will turn on with much less than 1mA. You are probably generating less than 10mA.

 

ahhhh...thank you!