Power receiving device, power transmitting device, wireless power transfer system, and wireless power transfer method

• US 9,583,964 B2
• Filed: 09/13/2012
• Issued: 02/28/2017
• Est. Priority Date: 09/26/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Murayama, Yuji, Nakano, Hiroaki, Fukuda, Shinichi
• Primary Examiner(s): Tran, Thienvu
• Assistant Examiner(s): Stables, David M
• Application Number:
  US13/613,064
• Publication Number:
  US 20130076153A1
• Time in Patent Office: 1,629 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source

Abstract

A power receiving unit includes a communication unit, a control unit, a detecting unit that performs metallic foreign matter detection, and a charge storage unit. The control unit is configured to control charging so electric power is stored in the charge storage unit for consumption by the detecting unit during Q-value measurement when the control unit receives a Q-value measurement command from the power transmitting device through the communication unit.

Claims

1. An energy receiver comprising:

a power reception coil configured to wirelessly receive power from an energy transmitter;

an energy storage element configured to store the power received from the energy transmitter after receiving a command related to detection of a foreign object;

a memory configured to store a threshold of a Q value of the energy receiver to compare with a calculated Q value of the energy transmitter; and

a control unit configured to supply the received power to a load connected to the energy receiver upon receipt of a charging command from the enemy transmitter,

wherein the charging command is issued after the detection of the foreign object.

2. The energy receiver of claim 1, further comprising:

a foreign object detector configured to detect the foreign object within a range of a wireless energy transmission of the enemy transmitter; and

wherein the control unit is further configured to supply the power to the foreign object detector from the energy storage element in an event the energy transmitter is not transmitting the power.

3. The energy receiver of claim 2,

wherein the control unit is further configured to supply the power to the foreign object detector from the energy storage element after receiving data corresponding to identification information of the energy receiver.

4. The energy receiver of claim 2,

wherein,

if the command includes identification information related to the energy receiver, the control unit is further configured to cause (i) the energy storage element to store the power, and (ii) the foreign object detector to search for the foreign object, and

if the command does not include the identification information related to the energy receiver, the control unit is further configured to only cause the energy storage element to store the power.

5. The energy receiver of claim 2,

wherein,

the foreign object detector is further configured to use the power stored in the energy storage element to detect the foreign object in an event the wireless energy transmission is suspended, and

the control unit is further configured to send a result generated by the foreign object detector to the energy transmitter in an event the wireless energy transmission is restarted after a suspension of the wireless energy transmission, the result related to whether the foreign object was detected by the foreign object detector.

6. The energy receiver of claim 2,

wherein the control unit, upon receipt of the command, is further configured to cause (i) the energy storage element to store the power, and (ii) the foreign object detector to search for the foreign object.

7. The energy receiver of claim 1,

wherein the energy storage element is a capacitor or a small secondary battery.

8. The energy receiver of claim 2,

wherein the foreign object detector is a Q-value measurement circuit further configured to detect a quality factor related to a resonance circuit.

9. The energy receiver of claim 1,

wherein the memory is further configured to store identification information of the energy receiver.