US 12,301,018 B2
Power transmission apparatus and wireless power transmission system
Yuki Shoji, Kanagawa (JP)
Assigned to Canon Kabushiki Kaisha, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Nov. 15, 2023, as Appl. No. 18/510,386.
Application 18/510,386 is a continuation of application No. 17/039,711, filed on Sep. 30, 2020, granted, now 11,843,257.
Claims priority of application No. 2019-186618 (JP), filed on Oct. 10, 2019.
Prior Publication US 2024/0097494 A1, Mar. 21, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H02J 50/12 (2016.01); H02J 50/70 (2016.01)
CPC H02J 50/12 (2016.02) [H02J 50/70 (2016.02)] 7 Claims
OG exemplary drawing
 
1. A wireless power transmission system comprising:
a power transmission apparatus; and
a power reception apparatus,
the power transmission apparatus comprising:
a first switching element having a first terminal and a second terminal;
a first capacitor having a third terminal connected to the first terminal and a fourth terminal connected to the second terminal;
a power transmission inductor connected to the first switching element and configured to wirelessly transmit alternating current (AC) power; and
a second capacitor connected between the first terminal and the power transmission inductor,
wherein an impedance Zc of the second capacitor at a switching frequency f of the first switching element is smaller than an impedance ZL of the power transmission inductor at the switching frequency f, and Zc/ZL satisfies Zc/ZL<0.62 at the switching frequency f,
the power reception apparatus comprising:
a power reception inductor configured to wirelessly receive AC power;
a third capacitor connected in series with the power reception inductor;
an alternating-current-to-direct-current (AC-to-DC) conversion circuit for converting AC power to direct-current (DC) power;
a load placed at an end of the AC-to-DC conversion circuit.