ADAPTIVE WIRELESS ENERGY TRANSFER SYSTEM

• US 20150061590A1
• Filed: 11/10/2014
• Published: 03/05/2015
• Est. Priority Date: 05/19/2010
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: Qualcomm, Inc.
• Inventors: Widmer, Hanspeter, Sieber, Lukas, Cook, Nigel
• Granted Patent: US 9,656,564 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: B60L 53/35 Means for automatic or assisted adjustment of the relative position of charging devices and vehicles
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• 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 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• 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 90/167 : 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 30/12 : Remote or cooperative charging

Abstract

Exemplary embodiments are directed to wireless power transfer using magnetic resonance in a coupling mode region between a charging base (CB) and a remote system such as a battery electric vehicle (BEV). The wireless power transfer can occur from the CB to the remote system and from the remote system to the CB. Load adaptation and power control methods can be employed to adjust the amount of power transferred over the wireless power link, while maintaining transfer efficiency.

Claims

1. An apparatus for wirelessly transmitting power, the apparatus comprising:

a power conversion circuit configured to convert power received from a power supply and operate in at least one of a first mode and a second mode;

a first power transfer component electrically coupled to the power conversion circuit, the first power transfer component configured to wirelessly transfer charging power to a second power transfer component at a receiver based at least in part on the converted power; and

a controller configured to reconfigure the power conversion circuit between at least the first and second modes based at least in part on a value indicative of a degree of coupling between the first and second power transfer components.

2. The apparatus of claim 1, wherein the first mode corresponds to a full-bridge mode and the second mode corresponds to a half-bridge mode.

3. The apparatus of claim 2, wherein the controller is configured to reconfigure the power conversion circuit to operate in the first mode in response to detecting the indicative value is greater than a threshold.

4. The apparatus of claim 2, wherein the controller is configured to reconfigure the power conversion circuit to operate in the second mode in response to detecting the indicative value is less than a threshold.

5. The apparatus of claim 1, further comprising a switching circuit configured to phase-switch the power conversion circuit when the power received from the power supply comprises 2 or more phases.

6. The apparatus of claim 1, further comprising a pulse-width modulation circuit electrically coupled to the power conversion circuit, the pulse-width modulation circuit configured to operate with a duty cycle of less than 50%.

7. The apparatus of claim 1, further comprising a sensor configured to detect at least one object between the first and second power transfer components, wherein the first power transfer component is configured to move in an x, or y, or z-direction based at least in part on the at least one detected object.

9. The apparatus of claim 1, wherein the first power transfer component is further configured to move between two discrete z-positions corresponding to a shorter distance and a longer distance between the first and second power transfer components, and wherein the power conversion circuit is further configured to operate in the first mode when the second power transfer component is located at the shorter distance and the second mode when the second power transfer component is at the longer distance.

10. The apparatus of claim 1, wherein the controller is configured to reconfigure the power conversion circuit between at least the first and second modes based at least in part on a distance between the first and second power transfer components.

11. The apparatus of claim 1, wherein the power conversion circuit is further configured to convert the received power to an alternating current at a wireless power transfer operating frequency.

12. The apparatus of claim 1, further comprising a resonant circuit comprising the first power transfer component, wherein the resonant circuit is configured to be substantially resonant at an operating frequency.

13. The apparatus of claim 12, wherein the controller is configured to at least one of cause the resonant circuit to operate off-resonance or partially detune the resonant circuit based at least in part on the value indicative of the degree of coupling.

8. The apparatus of claim 8, wherein the sensor comprises at least one of a mechanical resistance sensor, or a tactile sensor, or an ultrasonic sensor, or an optical sensor, or an electromagnetic sensor, or any combination thereof.

14. A method of wirelessly transmitting power, comprising:

converting power received from a power supply by a power conversion circuit;

operating the power conversion circuit in at least one of a first mode and a second mode;

wirelessly transferring charging power from a first power transfer component to a second power transfer component of a receiver based at least in part on the converted power; and

reconfiguring the power conversion circuit between the first and second modes based at least in part on a value indicative of a degree of coupling between the first and second power transfer components.

15. The method of claim 14, wherein the first mode corresponds to a full-bridge mode and the second mode corresponds to a half-bridge mode.

16. The method of claim 15, wherein reconfiguring the power conversion circuit between the first and second modes comprises reconfiguring the power conversion circuit to operate in the first mode when the indicative value is greater than a threshold.

17. The method of claim 15, wherein reconfiguring the power conversion circuit between the first and second modes comprises reconfiguring the power conversion circuit to operate in the first mode when the indicative value is less than a threshold.

18. The method of claim 14, further comprising:

detecting at least one object between the first and second power transfer components; and

moving the first power transfer component in at least one of an x, or y, or z-direction based at least in part on the at least one detected object to increase coupling between the first and second power transfer components.

19. An apparatus for wirelessly transmitting power, the apparatus comprising:

means for converting power received from a power supply;

means for operating the converting means in at least one of a first mode and a second mode;

means for wirelessly transferring charging power to a power transfer component based at least in part on the converted power; and

means for reconfiguring the converting means between the first and second modes based at least in part on a value indicative of a degree of coupling between the transferring means and the power transfer component.

20. An apparatus for wirelessly receiving power at an electric vehicle, the apparatus comprising:

a first power transfer component configured to wirelessly receive charging power via a magnetic field generated by a second power transfer component of a transmitter and provide the charging power to a load of the electric vehicle;

a sensor configured to detect at least one object between the first and second power transfer components; and

a controller configured to cause the first power transfer component to move in at least one of an x, or y, or z-direction based on at least one of the at least one detected object or a value indicative of a degree of coupling between the power transfer components.