US 12,230,977 B2
Contactless power feed apparatus and power transmission method
Goro Nakao, Kyoto (JP); Yuki Ito, Kyoto (JP); and Taichi Mishima, Kyoto (JP)
Assigned to OMRON Corporation, Kyoto (JP)
Filed by OMRON Corporation, Kyoto (JP)
Filed on Sep. 10, 2023, as Appl. No. 18/464,246.
Claims priority of application No. 2022-167894 (JP), filed on Oct. 19, 2022.
Prior Publication US 2024/0136860 A1, Apr. 25, 2024
Prior Publication US 2024/0235267 A9, Jul. 11, 2024
Int. Cl. H02J 50/12 (2016.01); H02J 50/80 (2016.01); H02M 1/00 (2007.01); H02M 3/00 (2006.01)
CPC H02J 50/12 (2016.02) [H02J 50/80 (2016.02); H02M 1/0054 (2021.05); H02M 3/01 (2021.05)] 11 Claims
OG exemplary drawing
 
1. A contactless power feed apparatus, comprising a power transmission device and a power reception device contactlessly receiving power from the power transmission device,
wherein the power reception device comprises:
a resonant circuit, having a reception coil receiving power from the power transmission device;
an estimation circuit, estimating a load resistance of an entirety of the contactless power feed apparatus; and
a reception-side communicator, transmitting an estimated value of the load resistance of the entirety of the contactless power feed apparatus to the power transmission device,
wherein the power transmission device comprises:
a transmission coil, supplying power to the power reception device;
a power supply circuit, comprising: a transmission-side DC-DC converter converting a voltage of DC power supplied from a DC power source; and a DC-AC converter, converting the DC power output from the transmission-side DC-DC converter into AC power, wherein the power supply circuit supplies the converted AC power to the transmission coil;
a transmission-side communicator, receiving the estimated value of the load resistance of the entirety of the contactless power feed apparatus from the reception-side communicator; and
a control circuit, controlling the transmission-side DC-DC converter, so that, in a case where the estimated value of the load resistance of the entirety of the contactless power feed apparatus is less than a predetermined allowed lower limit, an input/output gain of the transmission-side DC-DC converter is decreased by a first predetermined amount and, in a case where the estimated value of the load resistance of the entirety of the contactless power feed apparatus is equal to or greater than the predetermined allowed lower limit, the input/output gain of the transmission-side DC-DC converter is maintained or increased by a second predetermined amount.