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I got this simple wireless power mechanism:

http://dx.com/p/diy-wireless-charging-transmitter-receiver-solution-module-green-golden-dc-5-12v-194469

If I'll have the receiver end rotating at about 30 rev/sec, will this have any effect on the power transmission? Will it still work?

enter image description here

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Should still work with rotation.

Efficiency would depend on where the axis of rotation is relative to the coils. Best efficiency if the coils and rotation axis are coaxial.

Beware that you will loose efficiency if you have conductive material near the coils. The transmitting coil can induce eddy current in any metal parts, which will become a loss due to the parts' internal resistance. (This is also called "shorted turn effect". Induction cookers exploit it, by the way.)

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  • \$\begingroup\$ Actually, this is a very important point for me because I was planning to have the motor's massive shaft in the middle of the coil. Is there any way to avoid this effect? (except not putting it around the shaft) \$\endgroup\$ – shoosh Jul 3 '13 at 12:02
  • \$\begingroup\$ It's best if the shaft diameter is far smaller than the coil diameter. Also, if the operating freq is high (well over tens of KHZ,) then skin effect will prevent the system from "seeing" all but the outside of the metal shaft. \$\endgroup\$ – wbeaty Jul 5 '13 at 7:02
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I use this technique a lot at work and it works fine and we spin stuff up to 20,000 rpm. We also use the same coils for data transmission. The inter-coil gaps can be quite significant too. Power-send and power-receive coils are tuned to be resonant but for your project this is probably less important.

Power transfer on gaps of up to 40mm will work with resonant power coils. I don't know what your circuits are like but I'd expect to see 10mm gaps work.

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Two answers. 1) Probably not. And 2) Since you already have them, why not try it out? As long as you keep them on the same plane/axis, I don't see why it would not work as expected.

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