A homemade electric generator-problems?

Question

I was trying to make a small model electric generator to light an LED. I wrapped a LOT (1000) turns of enamal copper wire round a 35mm filem tube and put a magnet inside and shook it up , and connected thr led to the exposed ends ( after using sand paper on the wire ends ).
Nothing happended, Does anyone have any experience with this? or any tips for me?
Thanks

Answer 1

I see three potential problems here.

1) LED's works on DC and the unit you described will generate AC, if anything. So you may need to include a rectifier diode and possibly a filter capacitor to achieve enough continuous DC power to light the LED. You will need a minimum of 1.5V-2V of the correct polarity supplying a few milliamps to light most LED's. Also, if the voltage across the LED is applied in reverse above 5V-6V you may destroy the LED internally. And AC reverses continuously.

2) The arrangement you have will be very inefficient because the stator (stationary coil) is not wrapped around any iron or steel. You may possibly get the LED to light with this setup if you pass a strong enough bar magnet in the correct direction near the coil. But you could also generate more power by just wrapping the coil around something iron or steel like a nail or a bolt.

3) The direction that the magnet travels should consistently be at a right angle to the axis of the coil. In other words, your best results should occur when you pass one pole of a magnet across the end of the coil, not through the center of it. When the magnet moves only in the center of the coil, opposing currents in different parts of the coil will tend to cancel each other out.

One of my favorite generator experiments involves connecting two identical permanent magnet DC hobby motors together in series. If you spin one it acts as a generator and cause the other to turn as well. Spin the other and the process is reversed. It is like an invisible mechanical link.

WK

Answer 2

Put a small capacitor in parallel with the coil and use 10000 turns + a stronger magnet(the capacitor is to hold the charge you build up)

Answer 3

I think you might need a magnet that passes through the fields of other magnets..... go to "howstuffworks.com" and look at how generators work and how electric motors work.... hope this helps

oh an you might need something to store a charge, say a battery or capacitor, or something like that....