The induced voltage at Rx is proportional not only to the operating frequency but also to the number of turns N1 and N2. Is it therefore possible to increase delivered power by just increasing N1 or N2? If it is true, what is the penalty for that?

 

It would be useful if you would provide a diagram with the terms Rx, N1 and N2 clearly defined.

Wireless power transfer works like a transformer so increasing the primary or secondary turns will alter the induced voltage at the receiving end. I presume that Rx is some load resistance which is supplied from the secondary winding?

Look up "Maximum Power Transfer Theorem" and "Transformer Impedance Transformation" and you will see how the transformer windings can be adjusted to alter the value of the load "referred" to the primary side. If the load impedance referred to the primary is equal to the source impedance, then you have the ideal conditions for maximum power transfer.

 

Thank you