US 11,720,133 B2
Impedance adjustment in wireless power transmission systems and methods
Andre B. Kurs, Chestnut Hill, MA (US); Morris P. Kesler, Bedford, MA (US); Noam Katz, Lincoln, RI (US); Matthew Dillon, Hingham, MA (US); and Herbert Toby Lou, Berkeley, CA (US)
Assigned to WiTricity Corporation, Watertown, MA (US)
Filed by WiTricity Corporation, Watertown, MA (US)
Filed on Aug. 24, 2021, as Appl. No. 17/410,428.
Application 17/410,428 is a continuation of application No. 15/837,904, filed on Dec. 11, 2017, granted, now 11,112,814.
Application 15/837,904 is a continuation of application No. 14/459,870, filed on Aug. 14, 2014, granted, now 9,857,821, issued on Jan. 2, 2018.
Claims priority of provisional application 62/024,993, filed on Jul. 15, 2014.
Claims priority of provisional application 61/927,452, filed on Jan. 14, 2014.
Claims priority of provisional application 61/865,910, filed on Aug. 14, 2013.
Prior Publication US 2022/0083087 A1, Mar. 17, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G05F 1/625 (2006.01); H02J 50/12 (2016.01); H02J 50/80 (2016.01); B60L 53/122 (2019.01); G05F 1/66 (2006.01); H02J 7/00 (2006.01)
CPC G05F 1/625 (2013.01) [B60L 53/122 (2019.02); G05F 1/66 (2013.01); H02J 50/12 (2016.02); H02J 50/80 (2016.02); H02J 7/00712 (2020.01); H02J 2310/48 (2020.01); Y02T 10/70 (2013.01); Y02T 10/7072 (2013.01); Y02T 90/12 (2013.01); Y02T 90/14 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A power transmitting apparatus configured to wirelessly transmit power to a power receiving apparatus connected to an electrical load, the power transmitting apparatus comprising:
a circuit comprising an inductive element formed by at least one loop of conductive material, wherein the inductive element forms a resonator with at least a portion of the circuit; and
a controller configured to:
receive a signal indicating a phase difference between voltage and current waveforms associated with impedance matching circuitry of a power source of the power transmitting apparatus;
compare the phase difference between the voltage and current waveforms to one or more range limits for the phase difference to determine whether the phase difference is within an allowable range of phase differences;
adjust an impedance of the circuit by adjusting at least one of a tunable capacitance and a tunable inductance in the circuit if the phase difference is outside the allowable range of phase differences; and
transmit a control signal to a power amplifier of the power source to adjust at least one of a phase, a duty cycle, and a bus voltage of an amplifier of the power source if the phase difference is within the allowable range of phase differences, to drive the power transmitting apparatus toward a target output power.