WIRELESS POWER TRANSMISSION SYSTEM

• US 20120001497A1
• Filed: 06/28/2011
• Published: 01/05/2012
• Est. Priority Date: 07/02/2010
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: SADA, Tomokazu, KANNO, Hiroshi
• Granted Patent: US 8,970,070 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/502 the energy repeater being integrated together with the emitter or the receiver
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• 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 wireless power transmission unit according to the present invention transmits power wirelessly from a power transmitting section 100 to a power receiving section 200 through a resonant magnetic field. The unit includes: the power transmitting section 100, which resonates at a resonant frequency f0; at least one relay section 300, which can resonate at a frequency that is selected from multiple frequencies including the resonant frequency f0; and a resonance control section 600 that outputs information that specifies a resonance condition to be imposed on the relay section 300 according to the arrangement of the power receiving section 200 and that makes the relay section 300 resonate on the resonance condition that has been specified in accordance with that information.

Claims

1. A wireless power transmission unit that transmits power wirelessly from a power transmitting section to a power receiving section through a resonant magnetic field, the unit comprising:

the power transmitting section, which resonates at a resonant frequency f0;

at least one relay section, which is able to resonate at a frequency that is selected from multiple frequencies including the resonant frequency f0; and

a resonance control section that outputs resonance condition information that specifies a resonance condition to be imposed on the relay section according to the arrangement of the power receiving section and that controls the resonance condition imposed on the relay section in accordance with the resonance condition information.

2. The wireless power transmission unit of claim 1, wherein the at least one relay section includes first through n^th relay sections (where n is an integer that is equal to or greater than two) that are able to resonate at a frequency that is selected from multiple frequencies including the resonant frequency f0, and

wherein the resonance control section outputs resonance condition information that specifies resonance conditions to be imposed on the first through n^th relay sections according to the arrangement of the power receiving section and controls the resonance conditions imposed on the respective relay sections in accordance with the resonance condition information.

3. The wireless power transmission unit of claim 1, comprising a telecommunications system that conveys the resonance condition information from the resonance control section to the relay section(s).

4. The wireless power transmission unit of claim 1, comprising a position detecting section that detects the position of the power receiving section and outputting the power receiving section'"'"'s position information.

5. The wireless power transmission unit of claim 4, wherein the power receiving section'"'"'s position information is information about the position of a power receiving resonator included in the power receiving section.

6. The wireless power transmission unit of claim 1, wherein the relay section includes

a relay resonator, which resonates at the resonant frequency f0, and

a resonance adjustment circuit, which receives the resonance condition information from the resonance control section and which adjusts the resonance condition imposed on the relay resonator according to the resonance condition information.

7. The wireless power transmission unit of claim 1, wherein each of the resonance control section and the relay section includes a telecommunications section, and

wherein the relay section receives the resonance condition information from the resonance control section by way of the telecommunications sections.

8. The wireless power transmission unit of claim 7, wherein the position detecting section is provided for the relay section, and

wherein the telecommunications section of the relay section conveys the power receiving section'"'"'s position information, which has been provided by the position detecting section, to the telecommunications section of the resonance control section.

9. The wireless power transmission unit of claim 1, wherein each of the resonance control section and the position detecting section includes a telecommunications section, and

wherein the telecommunications section of the position detecting section conveys the power receiving section'"'"'s position information to the telecommunications section of the resonance control section.

10. The wireless power transmission unit of claim 1, wherein the resonance control section selects one of the relay sections, which is prevented from resonating at the resonant frequency f0, by reference to the power receiving section'"'"'s position information, and outputs the resonance condition information based on a result of the selection.

11. The wireless power transmission unit of claim 1, wherein the resonance control section prevents at least one of the relay sections, except the relay section that is located closest to the power receiving section, from resonating at the resonant frequency f0.

12. The wireless power transmission unit of claim 1, wherein if the power receiving section is located close to the power transmitting section, the resonance control section prevents one of the relay sections that is located closer to the power transmitting section than any other relay section from resonating at the resonant frequency f0.

13. The wireless power transmission unit of claim 1, wherein if the power receiving section is located between two adjacent ones of the relay sections, the resonance control section makes at least one of the relay sections that is located between the power transmitting section and the power receiving section resonate at the resonant frequency f0.

14. The wireless power transmission unit of claim 1, wherein if power is directly transmissible from the power transmitting section to the power receiving section, the resonance control section prevents every one of the relay sections, which is located between the power transmitting section and the power receiving section, from resonating at the resonant frequency f0.

15. The wireless power transmission unit of claim 1, wherein if power is directly transmissible from the power transmitting section to the power receiving section, the resonance control section prevents one of the relay sections, which is located closer to the power receiving section than any other relay section, from resonating at the resonant frequency f0.

16. The wireless power transmission unit of claim 1, wherein the power transmitting section includes

a resonance signal generating section that generates a resonance signal with the resonant frequency f0, and

a power transmitting resonator that generates a resonant magnetic field based on the resonance signal.

17. The wireless power transmission unit of claim 16, wherein the power transmitting section further includes a resonance adjustment circuit that changes the resonant frequency of the power transmitting resonator.

18. The wireless power transmission unit of claim 1, wherein the power transmitting section and the relay section are at least partially embedded in a wall, a floor or a ceiling of a building.

19. A device including a power receiving section to be used in combination with the wireless power transmission unit of claim 1,

wherein the power receiving section comprises

a power receiving resonator, which resonates at the resonant frequency f0, thereby receiving energy from either the power transmitting section or the relay section of the wireless power transmission unit, and

an output converting section that converts the energy into electric power energy.

20. The device of claim 19, wherein the power receiving section includes

a telecommunications section, which is able to receive resonance condition information from the resonance control section, and

a resonance adjustment circuit that controls the power receiving resonator in accordance with the resonance condition information.

21. The device of claim 20, wherein the power receiving section includes a position detecting section that detects the position of the power receiving section and outputting position information that has been obtained based on a result of the detection, and

wherein the position information is conveyed by the telecommunications section to the resonance control section.

22. A wireless power transmission system comprising:

a power transmitting section, which resonates at a resonant frequency f0;

at least one relay section, which is able to resonate at a frequency that is selected from multiple frequencies including the resonant frequency f0;

at least one power receiving section, which resonates at the resonant frequency f0; and

a resonance control section that outputs resonance condition information that specifies a resonance condition to be imposed on the relay section according to the arrangement of the power receiving section and for controlling the resonance condition imposed on the relay section in accordance with the resonance condition information.

23. The wireless power transmission system of claim 22, wherein the at least one power receiving section includes multiple power receiving sections, which are able to resonate at frequencies that are selected from multiple frequencies including the resonant frequency f0, and

wherein the resonance control section outputs resonance condition information that specifies resonance conditions to be imposed on the relay section and the multiple power receiving sections according to the arrangement of the power receiving sections, controls the resonance conditions imposed on the relay section and the power receiving sections in accordance with the resonance condition information, and supplies power to the power receiving sections time-sequentially.

24. The wireless power transmission system of claim 22, wherein the power transmitting section includes multiple power transmitting resonators, which are arranged so as to cross each other at right angles.

25. The wireless power transmission system of claim 24, comprising a direction detecting section that detects the direction of a power receiving resonator that is included in each said power receiving section and outputting direction information based on a result of the detection,

wherein the power transmitting section makes one of the multiple power transmitting resonators, which has been selected based on the direction information, resonate at the resonant frequency f0.