Wireless electric power supply method and wireless electric power supply apparatus

• US 8,692,411 B2
• Filed: 03/29/2010
• Issued: 04/08/2014
• Est. Priority Date: 03/31/2009
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Uchida, Akiyoshi
• Primary Examiner(s): Jackson, Stephen W
• Application Number:
  US12/748,898
• Publication Number:
  US 20100244581A1
• Time in Patent Office: 1,471 Days
• Field of Search: 307/104
• US Class Current: 307/104
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices

Abstract

A wireless electric power supply method includes: supplying electric power from a power supply section to a power-transmission resonance coil at a resonance frequency which causes magnetic field resonance; transmitting the electric power, supplied from the power supply section, as magnetic field energy from the power-transmission resonance coil to a power-reception resonance coil by using the magnetic field resonance, the power-transmission resonance coil being capable of being in magnetic field resonance with the power-reception resonance coil at the resonance frequency; monitoring the electric power supply by using a monitor section; comparing, by using a comparison section, the monitoring result obtained by the monitor section with characteristics data indicating the characteristics of the electric power supply performed by the power supply section; and controlling, by using a control section, the electric power supply performed by the power supply section, on the basis of the comparison result obtained by the comparison section.

Claims

1. A wireless electric power supply method comprising the operation of:

supplying electric power from a power supply section having a power supplying coil to a power-transmission resonance coil at a resonance frequency which causes magnetic field resonance, the power supplying coil being different from the power-transmission resonance coil;

transmitting the electric power, supplied from the power supply section, as magnetic field energy from the power-transmission resonance coil to a power-reception resonance coil by using the magnetic field resonance, the power-transmission resonance coil being capable of being in magnetic field resonance with the power-reception resonance coil at the resonance frequency;

monitoring the electric power supply from the power supplying coil to the power-transmission resonance coil by using a monitor section;

comparing, by using a comparison section, the monitoring result obtained by the monitor section with characteristics data indicating the characteristics of the electric power supply performed by the power supply section; and

controlling, by using a control section, the electric power supply performed by the power supply section, on the basis of the comparison result obtained by the comparison section.

2. The wireless electric power supply method according to claim 1, wherein when the comparison result obtained by the comparison section and the monitoring result obtained by the monitor section are normal, the control section causes the power supply section to supply the electric power.

3. The wireless electric power supply method according to claim 1, wherein when the comparison result obtained by the comparison section and the monitoring result obtained by the monitor section are abnormal, the control section causes the power supply section to halt supply of the electric power.

4. The wireless electric power supply method according to claim 3, wherein when the comparison result obtained by the comparison section and the monitoring result obtained by the monitor section are abnormal, the control section outputs an error signal indicating that the monitoring result is abnormal.

5. The wireless electric power supply method according to claim 1, wherein the control section causes the power supply section to supply the electric power with a first output value to the power-transmission resonance coil;

the monitor section monitors the electric power supply with the first output value;

the comparison section compares the monitoring result of the electric power supply with the first output value, the monitoring result being obtained by the monitor section, with the characteristics data indicating the characteristics of the electric power supply performed by the power supply section; and

when the comparison result obtained by the comparison section and the monitoring result obtained by the monitor section are normal, the control section causes the power supply section to supply the electric power with a second output value larger than the first output value.

6. The wireless electric power supply method according to claim 5, wherein when the control section causes the power supply section to supply the electric power with the first output value to the power-transmission resonance coil, the monitor section monitors the electric power supply with the first output value under the condition that the frequency of the electric power supplied by the power supply section is varied within a given frequency range including the resonance frequency.

7. The wireless electric power supply method according to claim 6, wherein the control section causes the power supply section to sweep the frequency continuously within the given frequency range.

8. The wireless electric power supply method according to claim 6, wherein the control section causes the power supply section to vary the frequency discretely to a plurality of given values within the given frequency range.

9. The wireless electric power supply method according to claim 1, wherein the power-transmission resonance coil, which is capable of being in magnetic field resonance with the power-reception resonance coil at the resonance frequency, receives the magnetic field energy transmitted from the power-transmission resonance coil by using the magnetic field resonance;

and a power reception section outputs, as electric power, the magnetic field energy received by the power-reception resonance coil.

12. The wireless electric power supply method according to claim 1, wherein at least one of a voltage and a current between an oscillation circuit included in the power supply section and the power supplying coil is monitored by the monitor section.

10. A wireless electric power supply apparatus comprising:

a power supply section, including a power supplying coil configured to supply electric power at a resonance frequency which causes magnetic field resonance;

a power-transmission resonance coil configured to transmit the electric power, supplied from the power supply section, as magnetic field energy by using the magnetic field resonance, the power-transmission resonance coil being capable of being in magnetic field resonance with a power-reception resonance coil at the resonance frequency, the power-transmission resonance coil being different from the power supplying coil;

the power-reception resonance coil being configured to receive the magnetic field energy, transmitted from the power-transmission resonance coil, by using the magnetic field resonance, the power-reception resonance coil being capable of being in magnetic field resonance with the power-transmission resonance coil at the resonance frequency;

a power reception section configured to output, as electric power, the magnetic field energy received by the power-reception resonance coil;

a store section configured to store characteristics data indicating the characteristics of the electric power supply;

a monitor section configured to monitor the electric power supply from the power supplying coil to the power-transmission resonance coil;

a comparison section configured to compare the monitoring result obtained by the monitor section with the characteristics data indicating the characteristics of the electric power supply performed by the power supply section; and

a control section configured to control the electric power supply, performed by the power supply section, on the basis of the comparison result obtained by the comparison section.

13. The wireless electric power supply apparatus according to claim 10, wherein the power supply section includes an oscillation circuit, and the monitor section monitors at least one of a voltage and a current between the oscillation circuit and the power supplying coil.

11. A wireless electric power supply apparatus comprising:

a power supply section, including a power supplying coil configured to supply electric power at a resonance frequency which causes magnetic field resonance;

a power-transmission resonance coil configured to transmit the electric power, supplied from the power supply section, as magnetic field energy by using the magnetic field resonance, the power-transmission resonance coil being capable of being in magnetic field resonance with a power-reception resonance coil at the resonance frequency, the power-transmission resonance coil being different from the power supplying coil;

a control section configured to cause the power-transmission resonance coil to be supplied with electric power at a plurality of frequencies;

a monitor section configured to monitor characteristics between the power-transmission resonance coil and the power supplying coil arising when the power-transmission resonance coil is supplied with electric power at the plurality of frequencies from the power supplying coil;

a store section configured to store characteristics data indicating the characteristics of the power-transmission resonance coil, the characteristics data corresponding to the plurality of frequencies;

a comparison section configured to compare the characteristics result obtained by the monitor section with the characteristics data stored in the store section; and

a control section configured to control the electric power supply, performed by the power supply section, on the basis of the comparison result obtained by the comparison section.

14. The wireless electric power supply apparatus according to claim 11, wherein the power supply section includes an oscillation circuit, and the monitor section monitors at least one of a voltage and a current between the oscillation circuit and the power supplying coil.