Wireless power with non-radiative magnetic resonances !

[hartiberlin]

Hi All,
this is a new and very interesting wireless power transfer technology.

Have a look at this:


http://www.mit.edu/~soljacic/wireless_power.html

and their papers:

http://www.aip.org/ca/2006/soljacic.pdf

and more technical:

http://arxiv.org/ftp/physics/papers/0611/0611063.pdf

It seems it is based on the High Q of an LC circuit.

So at resonance the receiver just pickups the energy of the transmitter
but otherwise not.

Very interesting.

Regards, Stefan.

[hartiberlin]

There was somebody over here,
who had claimed to have built a simular device with a magnetic resonance
transmitter and an array of at least 2 high Q   LC circuit coil  receivers
and he claimed to have gotten overunity with it, so that the
receiver also "sucks" adiitional power at the resonance frequency
from the stray environment magnetic radiation....

So here is now a professor from MIT that seems to do simular things...
although not claiming overunity...

When I find again the other thread here I will post again the link,
but I don?t find it right now, maybe one of you ?
Thanks.


Regards, Stefan.

[exnihiloest]

Hi All,
this is a new and very interesting wireless power transfer technology.

Have a look at this:


http://www.mit.edu/~soljacic/wireless_power.html

and their papers:

http://www.aip.org/ca/2006/soljacic.pdf

and more technical:

http://arxiv.org/ftp/physics/papers/0611/0611063.pdf

It seems it is based on the High Q of an LC circuit.

So at resonance the receiver just pickups the energy of the transmitter
but otherwise not.

Very interesting.

Regards, Stefan.

Hi all,

The coupling between two high Q resonnant circuits in order to transfer power is not really new. The system works, some are used at very short distance to power implants in the human body, but generally it has little practical applications for the following reasons:

- the source circuit must operate at low frequency otherwise it radiates too much. An example from Marin SoljaÃ,,iÃ,,‡ is a 1 meter loop operating at 10 Mhz. Such loops are real HF antennas that radiate up to several thousands Km around (they are used by ham radio operators). They are not convenient for short range distance.

- when the circuits operate at low frequencies (some tens to hundreds Khz), they radiate nearly nothing but:
   *the range distance is shorter
   *it is harder to get a high Q at a stable frequency
   *the coupling and resonnant frequency are very changing, depending on the proximity of conductive materials -human body included- that influence the resonnant frequency, or on the relative position and orientation of the loops.
Then the power at the receiving loop can change from several order of magnitude.

I think this system is quite intended for very short distance (< 1 mtr) between not moving objects requiring low power.

Fran?ois

[sypherios]

I must admit this idea sounds great and all, but we already know that power lines and such are causing dementia and tamper with our natural physiology. I cannot believe that energy being sent out wireless would be safe, it would do alo of harm to people in the room. it sounds good but there would have to be decades of testing done before release.


          Sincerely Sypherios

[otto]

Hello all,

@Stefan

a few minutes ago I readed in our newspapers and it was onTV that Soljacic was the first who did this.

In the same moment I sent a email to Soljacic and explained him that the news here claimed he was the first.

For all to know, TESLA WAS THE FIRST!!!!!

Im waiting what Soljacic has to say.

Otto