Methods and devices for controlling wireless power transfer levels

A system, comprising:

• a primary circuit comprising (i) a primary coil defining a primary coil axis;
• and (ii) a primary tank capacitor coupled to the primary coil;
• and
• a secondary circuit comprising (i) a secondary coil defining a secondary coil axis;
• (ii) a secondary tank capacitor;
• wherein the secondary coil and the tank capacitor define a resonant frequency;
• (iv) a rectifier coupled to the secondary coil so as to receive and rectify an electrical voltage induced in the secondary coil by the primary coil;
• (v) a switching capacitor electrically coupled to the tank capacitor;
• and (vi) a microcontroller electrically coupled to the switching capacitor so as to tune or detune a secondary resonant frequency of the secondary circuit with respect to a primary resonant frequency associated with the primary coil and the primary tank capacitor.

A method, comprising:

• inducing an oscillating voltage in a secondary circuit with an oscillating electromagnetic field in a primary circuit, wherein the secondary circuit is part of a telemetric device associated with an animal and the primary circuit is part of a cage in which the animal is physically confined;
• measuring a voltage associated with the oscillating voltage in the secondary circuit with a microcontroller using an analog input;
• and
• adjusting a resonant frequency difference between the secondary circuit and the primary circuit based on the measured voltage.