| CPC H03H 11/02 (2013.01) [H02J 50/12 (2016.02)] | 23 Claims |

|
1. A system, comprising:
an active variable reactance circuit, comprising:
an electrically-controllable switching element;
a passive reactive component connected to at least one terminal of the electrically-controllable switching element;
a resonator connected to the at least one terminal of the electrically-controllable switching element;
a radiofrequency (RF) pickup component configured to generate a pickup voltage proportional to an RF current or voltage passing through or across the resonator;
a switch controller sub-circuit that receives the pickup voltage and a control voltage, and generates a switch control signal having a duty cycle based on the control voltage and a phase based on the pickup voltage that switches the electrically-controllable switching element at a frequency of the RF current or voltage passing through or across the resonator,
wherein the switch controller sub-circuit comprises a comparator and an op-amp feedback loop, wherein the comparator receives the pickup voltage as a first input and a comparison voltage as a second input, the comparison voltage being an output of the op-amp feedback loop,
wherein the op-amp feedback loop receives the switch control signal as a first input and the control voltage as a second input, and outputs the comparison voltage to the comparator.
|