WIRELESS POWER SUPPLY SYSTEM, WIRELESS POWER TRANSMITTING DEVICE, AND WIRELESS POWER RECEIVING DEVICE

• US 20150091379A1
• Filed: 12/11/2014
• Published: 04/02/2015
• Est. Priority Date: 03/30/2009
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: UCHIDA, Akiyoshi
• Granted Patent: US 9,837,828 B2
• Time in Patent Office: Days
• US Class Current: 307/11
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

A wireless power supply system includes: a wireless power transmitting device configured to include a variable resonant circuit having a variable-controllable resonant frequency characteristic, and to transmit electric power wirelessly via the variable resonant circuit; a power transmission control unit configured to variably control the resonant frequency characteristic of the variable resonant circuit; and a plurality of wireless power receiving devices configured to include respective unique resonant circuits having respective unique resonant frequency characteristics which are different to each other, and to wirelessly receive power from the wireless power transmitting device by a magnetic field resonance mode arising as a result of the unique resonant circuit tuning to a resonant frequency of the variable resonant circuit.

Claims

1. A wireless power supply system, comprising:

a wireless power transmitting device configured to include a power transmitting resonant circuit having a predetermined resonant frequency characteristic, and to transmit electric power wirelessly via the power transmitting resonant circuit;

a plurality of wireless power receiving devices configured to include respective power receiving resonant circuits having a same resonant frequency characteristic as the power transmitting resonant circuit, and to wirelessly receive electric power from the wireless power transmitting device by a magnetic field resonance mode arising as a result of the power receiving resonant circuit tuning to a resonant frequency of the power transmitting resonant circuit; and

a power receiving control unit configured to perform on and off control of a circuit connection state of the power receiving resonant circuit for each of the wireless power receiving devices.

2. The wireless power supply system according to claim 1, wherein:

each of the wireless power receiving devices is configured to include;

a battery configured to store electric power received via the power receiving resonant circuit, and

a communication unit configured to exchange information regarding a storage status of the battery between the wireless power transmitting device and the plurality of wireless power receiving devices;

the wireless power transmitting device is configured to start transmission of electric power in accordance with a command from the communication unit; and

the power receiving control unit is configured to perform on and off control of the circuit connection state of the power receiving resonant circuit for each of the wireless power receiving devices in accordance with a command from the communication unit.

3. The wireless power supply system according to claim 1, wherein:

each of the wireless power receiving devices is configured to include a battery which is configured to store electric power received via the power receiving resonant circuit;

the power receiving control unit is configured to perform on and off control of the circuit connection state of the power receiving resonant circuit in accordance with a storage status of the battery for each of the wireless power receiving devices.

4. A wireless power supply system, comprising:

a wireless power transmitting unit configured to include a power transmitting resonant circuit including a power transmitting coil capable of transmitting electric power as magnetic field energy, the power transmitting resonant circuit having a characteristic of resonating at a power transmission frequency, and to transmit magnetic field energy from the power transmitting coil in a resonant state;

a plurality of wireless power receiving units configured to include a power receiving resonant circuit including a power receiving coil capable of taking in magnetic field energy, the power receiving resonant circuit having a characteristic of resonating at the power transmission frequency, and to receive magnetic field energy as electric power by means of the power receiving coil which resonates with the power transmitting coil and enters a resonant state; and

a power receiving control unit configured to control so as to degrade the resonance characteristic of the power receiving resonant circuit for each of the wireless power receiving units.

5. A wireless power receiving device, comprising:

a power receiving resonant circuit configured to have a resonant frequency characteristic which corresponds to a power transmitting side, and to wirelessly receive electric power from the power transmitting side;

a battery configure to store electric power which is received via the power receiving resonant circuit; and

a power receiving control unit configured to perform on and off control of a circuit connection state of the power receiving resonant circuit in accordance with a storage status of the battery, and to cause electric power to be wirelessly received from the power transmitting side by placing the circuit connection state in an “

on”

state to cause a resonant frequency of the power receiving resonant circuit to tune to a resonant frequency of a power transmitting side to generate a magnetic field resonance mode.