This instructable will show you the basics of creating your own cheap and easy wireless power mat, which you can use to power your device through the air!
New Update: complete list of components.
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Signing UpStep 1What is it? How does it work?
Inductive Coupling uses magnetic fields to transfer power. There is a primary coil, which generates a magnetic field. Then there is another secondary coil which is composed of a capacitor and a coil, the capacitor creates a resonant circuit with the primary and secondary coils. Seem easy? Well, before publishing this instructable I found many useful and a lot of non-useful info on the subject.
In my research I found, that to transfer power in very complicated. Once i did it I found that you do not need to go to MIT do do this sort of stuff. With a little electrical know how, this is easy.
It all starts with the transmitter. This transmitter needs to create 147.7 kHz square wave AC signal. Let me take a minute to explain this all. Level one on the frequency scale is Hertzs, then there is kHz, then MHz. MIT used a 10 mHz wave to drive there coils, but for this we will be using a 147.7 kHz signal so it does not get too complicated.
The secondary coil has a 0.02 uF capacitor. This will allow the two circuits to be coupled therefore, transferring power efficiently. The 0.02 uF capacitor is used only for this frequency, and the value of this capcitor will change depending on the frequency.
The primary coil creates a magnetic field, when another coil is placed near it, energy will be induced into it.
Be in mind that i could not get a hold of a 0.02uF capacitor so i used two 0.01uF capacitors connected together.
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help me
I used a PCB patterned coil for the transmitter/receiver.
https://sites.google.com/site/ddmcintosh2projects/inductive-charger
I didn't get it working yet.
umm, what do i need to put in my mobile phone, mp3 etc. to charge it from the coils?
are you found the solution in your case???
my case like your case...
i hope u can share u solution to me...
thank you...
i'am want to know...
how the secondary receive volt from primary...
can u explain to me....
thanks you..
Your 147.7 square wave AC signal generator just retired from the market, are there any alternatives?
How do you know wich capacitor to use to get that frequency? Could you show us the math?
Thanks ;)
Can someone point me in the direction of a kit I could use to generate the 149KHz signal?
Theres a possibility.
I haven't tried it yet but I plan on it.
which type of copper wires to be used, ( i.e thickness of wire)
what are the dimensions to be used please tel the length and breath
1) primary coil dimensions
2) secondary dimensions
and last thing is "how/ can we glow the led about 10 inches from primary coil ".
please help .we really want to do this . please answer ...
1) It's like 4 by 6 inches, and maybe 20 windings. 22 gauge.
2) It's about 20 windings and 3 by 4 inches. 30 gauge.
I'm interested in learning more about inductors, LC circuits, etc. Did you find any good books on these subjects? (where did you learn that you need a 147.7 kHz square wave AC signal)?