Wireless power transfer system that performs power transfer from determined power transmission device to power receiving device, power transmission device, power receiving device, and control method of wireless power transfer system

Patent metadata

Field	Value
Publication number	US-9755699-B2
Application number	US-201214378541-A
Country	US
Kind code	B2
Filing date	Feb 29, 2012
Priority date	Feb 29, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A wireless power transfer system includes a power receiving device and a plurality of power transmission devices that perform power transfer to the power receiving device. The power receiving device transmits request-power to the power transmission device, the request-power being power the power receiving device requests to be supplied with. The power transmission device, when receiving the request-power from the power receiving device, generates determination reference information based on the received request-power, the determination reference information being information to be used as a determination reference when the power receiving device selects the power transmission device, and transmits the generated determination reference information to the power receiving device. The power receiving device receives the determination reference information, selects the power transmission device from which the power receiving device is to receive power supply, and transmits a power transmission start request to the selected power transmission device.

First claim

The invention claimed is:

1. A wireless power transfer system comprising:
a power receiving device; and
a plurality of power transmission devices that perform power transfer to the power receiving device, wherein
the power receiving device transmits request-power to the power transmission device, the request-power being power the power receiving device requests to be supplied with,
the power transmission device
when receiving the request-power from the power receiving device, generates determination reference information based on the received request-power, the determination reference information being information to be used as a determination reference when the power receiving device selects the power transmission device, and
transmits the generated determination reference information to the power receiving device,
the power receiving device
receives the determination reference information,
selects, based on the determination reference information, the power transmission device from which the power receiving device is to receive power supply, and
transmits a power transmission start request to the selected power transmission device, and
the power transmission device starts power transfer to the power receiving device when receiving the power transmission start request, wherein
the system is communicably connected to a position information providing device that acquires a current position of the power receiving device,
the power transmission device
acquires a current position of the power receiving device from the position information providing device,
obtains a distance from the power transmission device to the power receiving device based on the acquired current position,
obtains transmission efficiency in transferring power to the power receiving device, the transmission efficiency corresponding to the obtained distance,
generates the determination reference information based on the received request-power and the obtained transmission efficiency, and
transmits the generated determination reference information to the power receiving device, and
the position information providing device
includes a plurality of antennas arranged adjacent to one another, the plurality of antennas receiving a positioning signal that is a wireless signal to be transmitted from the power receiving device,
obtains a direction α where the power receiving device exists as seen from the position information providing device, based on a phase difference of the received positioning signals, and
obtains a current position of the power receiving device based on the obtained direction.

2. The wireless power transfer system according to claim 1 , wherein
the power transmission device
determines whether or not the transmission efficiency exceeds a predetermined threshold, and
generates the determination reference information based on a result of the determination,
the power receiving device
selects the power transmission device based on the generated determination reference information.

3. The wireless power transfer system according to claim 1 , wherein
the power transmission device
stores a movement history of the power receiving device based on the current position of the power receiving device which is acquired from the position information providing device, and
generates the determination reference information based on the movement history, and
the power receiving device selects the power transmission device based on the generated determination reference information.

4. A control method of a wireless power transfer system that includes a power receiving device and a plurality of power transmission devices performing power transfer to the power receiving device, the system being communicably connected to a position information providing device that acquires a current position of the power receiving device, the method comprising:
the power receiving device
transmitting request-power to the power transmission device, the request-power being power the power receiving device requests to be supplied with,

the power transmission device
when receiving the request-power from the power receiving device, generating determination reference information based on the received request-power, the determination reference information being information to be used as a determination reference when the power receiving device selects the power transmission device, and

transmitting the generated determination reference information to the power receiving device,
the power receiving device
receiving the determination reference information,
selecting, based on the determination reference information, the power transmission device from which the power receiving device is to receive power supply, and
transmitting a power transmission start request to the selected power transmission device, and
the power transmission device
starting power transfer to the power receiving device when receiving the power transmission start request,
acquiring a current position of the power receiving device from the position information providing device,
obtaining a distance from the power transmission device to the power receiving device based on the acquired current position,
obtaining transmission efficiency in transferring power to the power receiving device, the transmission efficiency corresponding to the obtained distance,
generating the determination reference information based on the received request-power and the obtained transmission efficiency, and
transmitting the generated determination reference information to the power receiving device, and
the position information providing device
including a plurality of antennas arranged adjacent to one another, the plurality of antennas receiving a positioning signal that is a wireless signal to be transmitted from the power receiving device,
obtaining a direction α where the power receiving device exists as seen from the position information providing device, based on a phase difference of the received positioning signals, and
obtaining a current position of the power receiving device based on the obtained direction.

Assignees

• Masaoka Shinya
• Chugoku Electric Power

Inventors

• Masaoka Shinya

Classifications

• H02J50/10

  using inductive coupling · 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

• Y02T90/14

  Plug-in electric vehicles · CPC title

• B60L53/65

  involving identification of vehicles or their battery types · CPC title

• H02J50/05

  using capacitive coupling · CPC title