WIRELESS POWER TRANSMITTER AND WIRELESS POWER TRANSMISSION METHOD

• US 20170047786A1
• Filed: 04/10/2015
• Published: 02/16/2017
• Est. Priority Date: 04/11/2014
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: PARK, Yongcheol, LEE, Hyunbeom, LEE, Jaesung, JUNG, Byungsang, PARK, Jinmoo, LEE, Seonghun, LEE, Jihyun, SEO, Jeongkyo
• Granted Patent: US 10,177,592 B2
• Time in Patent Office: Days
• 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 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• 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 7/02 for charging batteries from ac mains by converters

Abstract

A wireless power transmitter is disclosed. The wireless power transmitter, which is capable of charging a plurality of wireless power receivers, includes: a plurality of coil cells; a main half-bridge inverter to which a main pulse signal is applied; a plurality of sub half-bridge inverters to which a first sub pulse signal or second sub pulse signal is applied; a current sensor that monitors the current through the coil cells; and a communications and control unit that controls the pulse signals applied to the main half-bridge inverter and sub half-bridge inverters and that communicates with the wireless power receivers, wherein the sub half-bridge inverters may be respectively connected to the coil cells.

Claims

1. A wireless power transmitter which is capable of charging a plurality of wireless power receivers, the wireless power transmitter comprising:

a plurality of coil cells;

a main half-bridge inverter to which a main pulse signal is applied;

a plurality of sub half-bridge inverters to which a first sub pulse signal or a second sub pulse signal is applied;

a current sensor configured to monitor the current of the coil cells; and

a communications and control unit configured to control the pulse signals applied to the main half-bridge inverter and sub half-bridge inverters and communicate with the wireless power receivers,

wherein the sub half-bridge inverters are respectively connected to the coil cells, and the first sub pulse signal is a phase-inverted version of the main pulse signal and the second sub pulse signal is a phase-controlled version of the main pulse signal.

2. The wireless power transmitter of claim 1, wherein the communications and control unit applies the second sub pulse signal to at least one of the sub half-bridge inverters to discover a power receiver.

3. The wireless power transmitter of claim 2, wherein, when at least one of the coil cells receives a response from a power receiver, the communications and control unit performs power transmission by applying the first sub pulse signal to the sub half-bridge inverter connected to the coil cell which has received the response from the power receiver.

4. The wireless power transmitter of claim 2, wherein, when at least one of the coil cells receives no response from a power receiver, the communications and control unit disables the sub half-bridge inverters.

5. The wireless power transmitter of claim 3, wherein, when the wireless power receiver from which the response is received is an inductive-type wireless power receiver, the communications and control unit performs power transmission by controlling the phase of the second power signal applied to the sub half-bridge inverter.

6. The wireless power transmitter of claim 3, wherein the response from the wireless power receiver comprises mode information, and the mode information indicates whether the wireless power receiver is inductive-type or resonant-type.

7. The wireless power transmitter of claim 2, wherein the second sub pulse signal is applied to at least one of the sub half-bridge inverters, either simultaneously or sequentially.

8. A wireless power transmission method for a wireless power transmitter comprising a main half-bridge inverter and a plurality of sub half-bridge inverters, the method comprising:

setting a selection signal to apply a second sub pulse signal to at least one of the sub half-bridge inverters;

transmitting power to at least one coil cell by applying an enable signal to the at least one sub half-bridge inverter; and

when the at least one coil cell receives a response from a wireless power receiver, changing the selection signal to apply a first sub pulse signal to the at least one sub half-bridge inverter,

wherein the first sub pulse signal is a phase-inverted version of a main pulse signal applied to the main half-bridge inverter and the second sub pulse signal is a phase-controlled version of the main pulse signal.

9. The method of claim 8, further comprising, when the at least one coil cell receives no response from a wireless power receiver, terminating the application of the enable signal.

10. The method of claim 8, further comprising, when the at least one coil cell receives a response from a wireless power receiver, determining whether the wireless power receiver is inductive-type or resonant-type.

11. The method of claim 10, further comprising, when the wireless power receiver is inductive-type, controlling the phase of the second sub pulse signal, instead of changing the selection signal.

12. The method of claim 8, wherein the response from the wireless power receiver comprises mode information, and the mode information indicates whether the wireless power receiver is inductive-type or resonant-type.

13. The method of claim 8, wherein the enable signal is applied to the at least one sub half-bridge inverter, either simultaneously or sequentially.