US 11,735,959 B2
Wireless power feeding system and power reception device
Hidehito Yoshida, Tokyo (JP); and Takuya Nakanishi, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/428,651
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Apr. 1, 2019, PCT No. PCT/JP2019/014424
§ 371(c)(1), (2) Date Aug. 5, 2021,
PCT Pub. No. WO2020/202422, PCT Pub. Date Oct. 8, 2020.
Prior Publication US 2022/0131413 A1, Apr. 28, 2022
Int. Cl. H02J 50/12 (2016.01); H02J 50/90 (2016.01)
CPC H02J 50/12 (2016.02) [H02J 50/90 (2016.02)] 12 Claims
OG exemplary drawing
 
1. A wireless power feeding system comprising:
a power transmission circuit portion to convert direct current (DC) power supplied from a main power supply, to alternating current (AC) power;
a power-transmission-side coil which is supplied with the AC power from the power transmission circuit portion;
input power controller to control the AC power to be supplied to the power-transmission-side coil by causing input power to the system to converge on a constant input power command value during a settling time determined in advance;
a power-reception-side coil which is magnetically coupled with the power-transmission-side coil supplied with the AC power from the power transmission circuit portion, and to which AC power is transmitted from the power-transmission-side coil through magnetic energy accumulated between the power-reception-side coil and the power-transmission-side coil;
a power reception circuit including a rectifier to convert the AC power transmitted to the power-reception-side coil, to DC, and a power-reception-side DC/DC converter to convert output voltage from the rectifier; and
reception voltage controller to perform reception voltage control in which the output voltage from the rectifier is converged to be a maximum efficiency voltage at which power transmission efficiency becomes maximum, wherein
when relative positions of the power-transmission-side coil and the power-reception-side coil are changed, the reception voltage controller obtains a degree of magnetic coupling between the power-transmission-side coil and the power-reception-side coil after the change of the relative positions on the basis of the output voltage from the rectifier, and updates the maximum efficiency voltage by calculating in real time a maximum efficiency voltage after the change of the relative positions on the basis of the degree of magnetic coupling, and
one or both of an update cycle of the maximum efficiency voltage and a control cycle of the reception voltage control are, in a range of being able to follow variation in the maximum efficiency voltage, not less than the settling time.