Wireless power transfer system, transmission device, and controlling method of wireless power transfer system

Patent metadata

Field	Value
Publication number	US-9520725-B2
Application number	US-201114369096-A
Country	US
Kind code	B2
Filing date	Dec 27, 2011
Priority date	Dec 27, 2011
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

A wireless power transfer system includes a power receiving device that receives transmission by wireless power transfer, a transmission device that has a transmission element that transmits transmission power to the power receiving device, the transmission device having a control mechanism that controls an oriented direction of the transmission element, and a positioning device that is connected communicably with the transmission device, the positioning device receiving with a plurality of antennas arranged adjacent to each other a positioning signal that is a wireless signal transmitted from the power receiving device, the positioning device having a positioning function that calculates a direction α in which the power receiving device exists when seen from the positioning device itself and a position of the power receiving device, based on a phase difference between the received positioning signals.

First claim

The invention claimed is:

1. A wireless power transfer system comprising:
a power receiving device that receives transmission by wireless power transfer;
a transmission device that has a transmission element that transmits transmission power to the power receiving device, the transmission device having a control mechanism that controls an oriented direction of the transmission element;
a positioning device that is connected communicably with the transmission device, the positioning device receiving with a plurality of antennas arranged adjacent to each other a positioning signal that is a wireless signal transmitted from the power receiving device, the positioning device having a positioning function that calculates a direction α in which the power receiving device exists when seen from the positioning device itself and a position of the power receiving device, based on a phase difference between the received positioning signals, wherein
the transmission device
acquires from the positioning device a direction α in which the power receiving device exists, controls the control mechanism so that the oriented direction of the transmission element faces the direction of the power receiving device based on the acquired direction α, and starts transmission, and
acquires a distance between the transmission device itself and the power receiving device based on the position of the power receiving device acquired from the positioning device, and obtains a permissible range of transmission efficiency at the time of transmitting the transmission power to the power receiving device, which corresponds to the acquired distance,

the power receiving device transmits to the transmission device a power value that is currently being supplied from the transmission device,
the transmission device
receives the power value sent from the power receiving device,
obtains a current transmission efficiency, based on the received power value and a power value of the transmission power currently being transmitted from the transmission element, and
in the case that the current transmission efficiency deviates from the permissible range, acquires again from the positioning device a direction α in which the power receiving device exists, and based on the acquired direction α, controls the oriented direction of the transmission element so that the oriented direction of the transmission element faces the direction of the power receiving device.

2. The wireless power transfer system according to claim 1 , wherein
in the case that the transmission efficiency deviates from the permissible range, the transmission device stops the transmission to the power receiving device, acquires again from the positioning device the direction α in which the power receiving device exists, performs control so that the oriented direction of the transmission element faces the direction of the power receiving device, based on the direction α in which the acquired power receiving device exists, and subsequently restarts the transmission to the power receiving device.

3. The wireless power transfer system according to claim 1 , wherein
the transmission device transmits to the power receiving device a positioning signal transmitting request that is information requesting the power receiving device to transmit the positioning signal,
the positioning device performs positioning of the power receiving device based on the positioning signal that the power receiving device transmits according to the positioning signal transmitting request, and
the transmission device transmits the positioning signal transmitting request during performing the transmission to the power receiving device, and after transmitting the positioning signal transmitting request, in the case that the positioning device does not receive the positioning signal from the power receiving device within a predetermined time, the transmission device stops the transmission to the power receiving device.

4. The wireless power transfer system according to claim 1 , wherein
the power receiving device includes a power receiving element that receives the transmission power and a control mechanism that controls an oriented direction of the power receiving element,
the transmission device transmits to the power receiving device the direction α in which the power receiving element exists and a position where the power receiving device exists acquired from the positioning device,
the power receiving device receives the direction α and the position, and adjusts the oriented direction of the power receiving element to a direction of the transmission device based on the received direction α and the position.

5. The wireless power transfer system according to claim 4 , wherein
the transmission device supplies by wireless power transfer to the power receiving device power needed to adjust the oriented direction of the power receiving device.

6. A transmission device of a wireless power transfer system according to claim 1 , comprising:
a transmission element that transmits the transmission power to the power receiving device; and
a control mechanism that controls the oriented direction of the transmission element, wherein the transmission device
acquires from the positioning device a direction α in which the power receiving device exists, controls the control mechanism so that the oriented direction of the transmission element faces the direction of the power receiving device based on the acquired direction α and starts transmission, and
acquires the distance between the transmission device itself and the power receiving device based on the position of the power receiving device acquired from the positioning device, and obtains a permissible range of transmission efficiency at the time of transmitting the transmission power to the power receiving device, which corresponds to the acquired distance,
receives the power value sent from the power receiving device,
obtains a current transmission efficiency, based on the received power value and a power value of the transmission power currently being transmitted from the transmission element, and
in the case that the current transmission efficiency deviates from the permissible range, the transmission device acquires again from the positioning device a direction α in which the power receiving device exists, and based on the acquired direction α, controls the oriented direction of the transmission element so that the oriented direction of the transmission element faces the direction of the power receiving device.

7. The transmission device according to claim 6 , wherein
in the case that the transmission efficiency deviates from the permissible range, the transmission device stops the transmission to the power receiving device, acquires again from the positioning device a direction α in which the power receiving device exists, performs control so that the oriented direction of the transmission element faces the direction of the power receiving device, based on the direction α in which the acquired power receiving device exists, and subsequently restarts transmission to the power receiving device.

8. A controlling method of a wireless power transfer system, the wireless power transfer system including
a power receiving device that receives transmission by wireless power transfer,
a transmission device that has a transmission element that transmits transmission power to the power receiving device, the transmission device having a control mechanism that controls an oriented direction of the transmission element,
a positioning device that is connected communicably with the transmission device, the positioning device receiving with a plurality of antennas arranged adjacent to each other a positioning signa

Assignees

• Masaoka Shinya
• Mito Katsuhiko
• Hirano Akira
• Okubo Norihiro
• Naito Masaki
• Takeuchi Yasunori
• Chugoku Electric Power

Inventors

• Masaoka Shinya
• Mito Katsuhiko
• Hirano Akira
• Okubo Norihiro
• Naito Masaki
• Takeuchi Yasunori

Classifications

• H02J50/12

  of the resonant type · CPC title

• H02J50/80 Primary

  involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices · CPC title

• H02J17/00

  Electricity · mapped topic

• H02J5/005 Primary

  Electricity · mapped topic

• H02J50/402 Primary

  the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas · CPC title