Wireless power transmitter and wireless power transmission method

• US 9,184,634 B2
• Filed: 07/10/2012
• Issued: 11/10/2015
• Est. Priority Date: 08/26/2011
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Jung, Woo Kil
• Primary Examiner(s): AMAYA, CARLOS DAVID
• Application Number:
  US14/241,146
• Publication Number:
  US 20140265622A1
• Time in Patent Office: 1,218 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H02J 5/00 Circuit arrangements for transfer of electric power between ac networks and dc networks H02J3/36 takes precedence
• 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
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Disclosed are a wireless power transmitter and a wireless power transmission method thereof. The wireless power transmitter, which wirelessly transmits power to a wireless power receiver, includes a power source to generate AC power, a transmission coil receiving power from the power source to generate a magnetic field, a transmission resonance coil coupled with the transmission coil to transmit power generated by the magnetic field to the wireless power receiver using resonance, and a detector detecting an existence state of the wireless power receiver by detecting power transmitted through the transmission resonance coil.

Claims

1. A wireless power transmitter which wirelessly transmits power to a wireless power receiver, the wireless power transmitter comprising:

a power source configured to supply the power to the wireless power transmitter;

a transmission resonance coil capable of generating a magnetic field and transmitting the power using resonance to the wireless power receiver that has a resonant frequency value equal to that of the wireless power transmitter;

a detector configured to measure an intensity of the magnetic field; and

a controller configured to determine an existence state of the wireless power receiver based on the measured intensity of the magnetic field and to control a transmission pattern of the magnetic field according to the determined existence state of the wireless power receiver,

wherein the controller controls to generate the transmission pattern of the magnetic field that is pulsed at a predetermined time interval for a specific time if the wireless power receiver does not exist and to generate the transmission pattern of the magnetic field that is continuous if the wireless power receiver exists, and

wherein the controller further controls a power intensity of the magnetic field to vary during the continuous generation of the transmission pattern based on a power requirement of the wireless power receiver.

2. The wireless power transmitter of claim 1, wherein the power source continuously supplies the power if the wireless power receiver exists.

3. The wireless power transmitter of claim 2, wherein the detector measures an intensity of current output from the power source while the power source continuously supplies the power.

4. The wireless power transmitter of claim 3, wherein the controller is further configured to adjust the power according to the intensity of the current output from the power source while the power source continuously supplies the power.

5. The wireless power transmitter of claim 4, wherein the controller is further configured to re-determine the existence state of the wireless power receiver according to the intensity of current output from the power source while the power source continuously supplies the power, and controls the transmission pattern of the magnetic field to be pulsed if the wireless power receiver does not exist.

6. A wireless power transmission method by a wireless power transmitter to wirelessly transmit power to a wireless power receiver, the wireless power transmission method comprising:

supplying, via a power source, the power to a transmission resonance coil;

generating a magnetic field, via the transmission resonance coil, for transmitting the power using resonance to the wireless power receiver that has a resonant frequency value equal to that of the wireless power transmitter;

measuring, at a detector, an intensity of the magnetic field generated by the transmission resonance coil;

determining, via a controller, an existence state of the wireless power receiver based on the measured intensity of the magnetic field; and

controlling, via the controller, a transmission pattern of the magnetic field according to the existence state of the wireless power receiver,

wherein the controller controls to generate the transmission pattern of the magnetic field that is pulsed at a predetermined time interval for a specific time if the wireless power receiver does not exist and to generate the transmission pattern of the magnetic field that is continuous if the wireless power receiver exits, and

wherein the controller further controls a power intensity of the magnetic field to vary during the continuous generation of the transmission pattern based on a power requirement of the wireless power receiver.

7. The wireless power transmission method of claim 6, wherein the supplying of the power further comprises continuously supplying the power if the wireless power receiver exists.

8. The wireless power transmission method of claim 7, further comprising:

measuring an intensity of current output from the power source while the power source continuously supplies the power.

9. The wireless power transmission method of claim 8, further comprising:

adjusting, via the controller, the power according to the intensity of the current output from the power source while the power source continuously supplies the power.

10. The wireless power transmission method of claim 9, further comprising:

re-determining the existence state of the wireless power receiver according to the intensity of current output from the power source while the power source continuously supplies the power; and

controlling the transmission pattern of the magnetic field to be pulsed if the wireless power receiver does not exist.