Tuning Electromagnetic Fields Characteristics for Wireless Energy Transfer Using Arrays of Resonant Objects

• US 20120217817A1
• Filed: 08/12/2011
• Published: 08/30/2012
• Est. Priority Date: 02/28/2011
• Status: Abandoned Application

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Wang, Bingnan, Yerazunis, William S., Duan, Chunjie, Teo, Koon Hoo
• Application Number:
  US13/209,336
• Publication Number:
  US 20120217817A1
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: B60L 53/65 involving identification of vehicles or their battery types
• CPC Class Codes: B66B 7/00 Other common features of elevators
• CPC Class Codes: H02J 50/05 using capacitive coupling
• 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 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/167 Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/14 Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

A system for exchanging energy wirelessly includes an array of objects, wherein each object is electromagnetic (EM) and non-radiative and generates an EM near-field in response to receiving the energy. Each object in the array is electrically isolated from the other objects and arranged at a distance from all other objects. An energy driver provides the energy to the array of objects. A receiver, at a relative position with respect to the array receives the energy via resonant coupling of evanescent waves. The system can tunes characteristics of the EM near-field depending on a relative position of the receiver with respect to the array. The tuning can affect frequency, phase and amplitude of the energy field.

Claims

1. A system for exchanging energy wirelessly, comprising:

an array of objects, wherein each object is electromagnetic (EM) and non-radiative and generates an EM near-field in response to receiving the energy, wherein each object in the array is electrically isolated from the other objects and arranged at a distance from all other objects;

an energy driver configured to provide the energy to the array of objects;

a receiver, at a relative position with respect to the array, to receive the energy via resonant coupling of evanescent waves;

means for tuning characteristics of the EM near-field depending on a relative position of the receiver with respect to the array.

2. The system of claim 1, wherein the characteristics include a desired frequency for all relative position of the receiver with respect to the array to obtain a highest energy transfer efficiency at all positions for a highest energy transfer efficiency for all positions.

3. The system of claim 1, wherein the means for tuning further comprises;

a detection and feedback module configured to detect feedback information;

a controller configured to processes the feedback information and generating a frequency tuning message for the energy driver.

4. The system of claim 3, wherein the feedback information includes an amount of reflected energy from the array, and the frequency tuning message obtains a lowest reflected energy.

5. The system of claim 3, wherein the feedback information includes the position of the receiver.

6. The system of claim 1, wherein the tuning is dynamic.

7. The system of claim 6, wherein the receiver is moving.

8. The system of claim 1, wherein the means for tuning further comprises;

a detection and feedback module configured to detect feedback information;

a controller configured to processes the feedback information and generating a phase tuning message for a tunable phase shifter connected to the array at two or more feed points.

9. The system of claim 8, wherein an energy distribution on the array is determined by a superposition of patterns of the EM near-field at all feed points.

10. The system of claim 8, wherein the feedback information includes an amount of reflected energy from the array, and the phase tuning message obtains a lowest reflected energy.

11. The system of claim 8, wherein the feedback information includes an amount of energy received by the receiver.

12. The system of claim 8, wherein the feedback information includes the position of the receiver.

13. The system of claim 1, wherein the characteristics include a desired frequency and a desired phase for all relative position of the receiver with respect to the array to obtain a highest energy transfer efficiency at all positions for a highest energy transfer efficiency for all positions.

14. The system of claim 1, wherein a resonant frequency of the receiver is tuned for best coupling at a desired frequency of the system.

15. The system of claim 14, wherein the receiver includes a varactor.

16. The system of claim 1, wherein the resonant frequency is tuned by a micro-electro-mechanical system device in the receiver.

17. The system of claim 1, wherein the resonant frequency is tuned by ferroelectric material at the receiver.

18. The system of claim 6, wherein the generates an amplitude tuning message for a tunable phase shifter connected to the array at two or more feed points.

19. A method for exchanging energy wirelessly, comprising the steps of:

distributing energy to an array of objects, wherein each object is electromagnetic (EM) and non-radiative and generates an EM near-field in response to receiving the energy, wherein each object in the array is electrically isolated from the other objects and arranged at a distance from all other objects;

receiving the energy in a receiver at a position relative to the array via resonant coupling of evanescent waves;

tuning characteristics of the EM near-field depending on the relative position of the receiver with respect to the array.

20. The method of claim 19, wherein the characteristics include frequencies of the EM near-field.

21. The method of claim 19, wherein the characteristics include phases of the EM near-field.