HELP with Wireless power transmission of miniscule harvested energy

[jjoll]

Hi,
I am about to harvest a tiny amount of energy from a peltier device or mini hydraulic generator (I am predicting to be around 10mW) and I am planning to wirelessly transfer this energy to another point (to the receiving end about 1 cm away) but I cannot transfer the power with wires. It should be wireless! I was just wondering if this is even feasible, given the small amount of energy and power that I am trying to transfer? any suggestion how can I go about this only using off-the-shelf product?
I was personally thinking of maybe using LTC3108 (Ultralow Voltage Step-Up Converter and Power Manager)(http://www.linear.com/product/LTC3108) to step up my the voltage and just use some sort of induction energy transfer. But I need the transmitting part (the power generator , resonant circuit, coils and etc to be as small as possible [something like 2cm by 2cm by 4cm]). Any better idea? I have heard of radio frequency (RF) power transfer (used in a few implantable medical components: [http://media.sjm.com/newsroom/media...CardioMEMS-Technology-Fact-Sheet/default.aspx ]) as well but I dont anything about it.

thanks in advance

 

[BradtheRad]

Did you investigate the list of related threads at the bottom of this column?

Your idea resembles wireless charging of hearing aids and toothbrushes. You might find hints how to build a suitable system.

 

[CataM]

(I am predicting to be around 10mW)

Very little power.. you may want to think to shield your coils. There is where a FEM simulator comes in.

(to the receiving end about 1 cm away)

Then coils should be around 1 cm in radius. You can try many topologies of coils e.g. flat spiral, helical...

PTE (power transfer efficiency) usually depends on the figure of merit FOM= k²Q_TxQ_Rx so that would say to use high frequency BUT at high frequency skin effect and proximity effect comes in and reduces Q..

You can try with some RF power amplifiers as inverters to drive the Tx coil.

As a reference book, you can take a look at this book : Wireless Power Transfer for Medical Microsystems-Tianjia Sun