The WiTricity group has made a lot of buzz but no internet article explains the exact method that they are using. Does anyone know how it works?
[Physics] How exactly does WiTricity’s wireless power transfer using resonance work
electricityelectromagnetic-inductionelectromagnetismresonance
Related Solutions
I think John has assumed that the voltages are constant along the diagonals, however this is not the case as the numerical example shows.
For Example:
After using LTspiceIV to create a circuit just like the one you are proposing I have been able to analyse the voltages at set points between the resistors.
Looking at your equation you are assuming that the voltage is constant across the diagonal nodes. After analyzing these nodes using the software I can assure you that they do differ.
Voltage between resistors are as follows
R2-R3 = 627.66 mV
R12-R13 =670.213 mV
R14-R15 =627.66 mV
Using this software it is then easy to calculate the total resistance
this is 2.13636 (5dp)
Best Answer
The method that WiTricity implements is that of magnetic resonance coupling. Resonance is done to ensure efficient exchange of energy between the transmitter and the receiver.
The method is very simple. If you take a coil and pass alternating current through it, it will produce alternating magnetic field around itself (like a solenoid). Now, place another coil in the vicinity of the first coil. The alternating magnetic field causes alternating flux through the second coil. This generates an emf in second coil and hence provides power to load.
Witricity's method created a buzz because they portrayed it as a new invention but actually its just an improved version of inductive coupling.