Tested generator coil

A project log for Mini Electromagnetic "Shake" Lantern

A mini electromagnetic lantern that can be recharged by shaking

Chris JonesChris Jones 05/08/2022 at 07:312 Comments

Built a coil to test the power generation using some 28 awg magnet wire.

 After marking out ~25mm section in the middle of  the 1/2" tubing I did 6 layers of 28 awg, gluing it every so often to ensure it didn't uncoil on me.

This came out to ~250-300 turns.

When testing with the magnets I was only able to generate ~.5 volts. I tried with both 5 magnets and 10 and it still roughly the same voltage output. I think I need to get more turns to get to a higher voltage. 

The issue is with the 28 awg wire I am only able to go 1 or 2 more layers before I use up all of the space available for the outside 1" tubing. So I need to try switching out to a smaller gauge. 

I went ahead and put in an order for some 32 awg which should give me close to 2x the turns in the same cross section. 

I will also redesign the drill holder and a couple coil edges to help make the process a little easier next time. A tighter and neater coil should generate a higher voltage.


adriancubas wrote 05/08/2022 at 14:13 point

Hello, I suggest you increase the magnetic permeability of the core in your coil. Place a few nails between the coil and the plastic cylinder. Hold them with the same enameled wire. If the magnets get stuck by the magnetic attraction increase their mass by adding magnets or nuts for example. I would love to know if the voltage obtained was increased. Another way would be to add many more turns but you would be increasing the electrical resistance and with it the current would drop.

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Chris Jones wrote 05/08/2022 at 18:32 point

Interesting idea, I can try that but I would assume that might make the magnet stick to the sides of the tubing.

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