Wireless power feeding system and wireless power feeding method

• US 9,472,974 B2
• Filed: 09/09/2014
• Issued: 10/18/2016
• Est. Priority Date: 07/28/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Shionoiri, Yutaka, Kamata, Koichiro, Sato, Misako, Maeda, Shuhei
• Primary Examiner(s): KAPLAN, HAL IRA
• Application Number:
  US14/481,435
• Publication Number:
  US 20140375263A1
• Time in Patent Office: 770 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• 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 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

An object is to provide a power feeding system and a power feeding method which are more convenient for a power feeding user at the power receiving end. An object is to provide a power feeding system and a power feeding method which also allow a power feeding provider (a company) which feeds power (at the power transmitting end) to supply power without waste. A power feeding device which wirelessly supplies power to a power receiver detects the position and the resonant frequency of the power receiver to be supplied with power, and controls the frequency of a power signal to be transmitted to the power receiver on the basis of the information. An efficient power feeding service can be offered by transmitting a power signal to the power receiver at an optimum frequency for high power transmission efficiency.

Claims

1. A wireless power receiver comprising:

a housing;

a display panel;

a transmission/reception circuit portion;

a signal processing circuit portion; and

a power storage portion comprising a secondary battery,

wherein the wireless power receiver is configured to;

emit a detection signal apt to allow a power feeding device to detect a resonant frequency of the wireless power receiver, the detection signal comprising a plurality of signals each having a different frequency;

receive a power signal having a frequency adjusted to the resonant frequency of the wireless power receiver determined from the detection signal; and

store power transmitted by the power signal in the secondary battery of the power storage portion.

2. A wireless power receiver according to claim 1, further comprising a voltage/current detection portion,

wherein the wireless power receiver is further configured to emit a signal for requesting beginning or end of power feeding in accordance with a detected voltage, a detected current or detected current and voltage outputted from the secondary battery.

3. A wireless power receiver according to claim 1, further comprising a memory,

wherein the wireless power receiver is further configured to emit identification information stored in the memory.

4. A wireless power receiver according to claim 1,

wherein the resonant frequency is one of the frequencies of the plurality of signals.

5. A wireless power receiver according to claim 1, the wireless power receiver being configured to perform its functions without modifying the resonant frequency.

6. A wireless power receiver according to claim 1, wherein the wireless power receiver is one of a portable electronic device, category comprising mobile phones, notebook personal computers, cameras including digital cameras or digital video cameras, digital photo frames, portable game machines, personal digital assistants, and electronic books, and a transportation means driven by an electric motor, category comprising automobiles, motorized bicycles including motor-assisted bicycles, aircrafts, ships, and railroad cars.

7. A wireless power feeding method for a wireless power receiver comprising the steps of:

emission of a detection signal apt to allow a power feeding device to detect a resonant frequency of the wireless power receiver by the wireless power receiver, the detection signal comprising a plurality of signals each having a different frequency;

reception of a power signal having a frequency adjusted to the resonant frequency of the wireless power receiver; and

storage of power transmitted by the power signal in a power storage portion of the wireless power receiver,

wherein the wireless power receiver comprises a housing and a display panel.

8. A wireless power feeding method for a wireless power receiver according to claim 7, further comprising the step of emission of identification information by the wireless power receiver.

9. A wireless power feeding method for a wireless power receiver according to claim 7, further comprising the steps of:

detection of voltage, current, or voltage and current outputted from a secondary battery of the power storage portion of the wireless power receiver.

10. A wireless power feeding method for a wireless power receiver according to claim 7,

wherein the resonant frequency is one of the frequencies of the plurality of signals.

11. A wireless power feeding method for a wireless power receiver according to claim 7, the wireless power receiver being configured to perform its function without modifying the resonant frequency.

12. A wireless power feeding method for a wireless power receiver according to claim 7, wherein the wireless power receiver is one of a portable electronic device, category comprising mobile phones, notebook personal computers, cameras including digital cameras or digital video cameras, digital photo frames, portable game machines, personal digital assistants, and electronic books, and a transportation means driven by an electric motor, category comprising automobiles, motorized bicycles including motor-assisted bicycles, aircrafts, ships, and railroad cars.

13. A wireless power feeding device comprising:

a transmission/reception circuit portion;

a signal processing circuit portion having a resonant frequency detection function and a power transmission control function; and

a power supply portion,

wherein the wireless power feeding device is configured to;

receive detection signals transmitted by one or more wireless power receivers, each detection signal comprising a plurality of signals each having a different frequency;

determine resonant frequencies of the one or more wireless power receivers based on the detection signals;

adjust frequencies of power signals to be emitted by the wireless power feeding device, based on the resonant frequencies; and

emit the power signals.

14. A wireless power feeding device according to claim 13,

wherein the wireless power feeding device is further configured to receive identification information emitted by the one or more wireless power receivers.

15. A wireless power feeding device according to claim 13,

wherein the resonant frequencies are frequencies of the plurality of signals.

16. A wireless power feeding device according to claim 13, wherein the one or more wireless power receivers are each one of a portable electronic device, category comprising mobile phones, notebook personal computers, cameras including digital cameras or digital video cameras, digital photo frames, portable game machines, personal digital assistants, and electronic books, and a transportation means driven by an electric motor, category comprising automobiles, motorized bicycles including motor-assisted bicycles, aircrafts, ships, and railroad cars.