Wireless power transmitter and wireless power transfer method thereof in many-to-one communication

Patent metadata

Field	Value
Publication number	US-9306401-B2
Application number	US-201213538263-A
Country	US
Kind code	B2
Filing date	Jun 29, 2012
Priority date	Jun 29, 2011
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A wireless power transmitter for transmitting power in a wireless manner by forming a wireless power signal and a wireless power transfer method thereof are capable of optimizing transmission efficiency for a plurality of wireless power receivers, by deciding an optimal transmission parameter (especially, a frequency corresponding to the wireless power signal or a resonant frequency) for the plurality of wireless power receivers based on control errors received from the plurality of wireless power receivers, respectively, via respective time slots allocated to the plurality of wireless power receivers.

First claim

What is claimed is:

1. A wireless power transfer method for a wireless power transmitter which transfers power in a wireless manner by forming a wireless power signal, the method comprising:
detecting a plurality of wireless power receivers;
acquiring control errors corresponding to a first control error value and a second control error value from the detected plurality of wireless power receivers, respectively;
detecting transmission parameters corresponding to the plurality of wireless power receivers, respectively, based on the first control error value and the second control error value; and
transferring power in the wireless manner to each of the plurality of wireless power receivers by forming the wireless power signal based on the detected transmission parameters,
wherein the first control error value is received from a first wireless power receiver in a first time duration which is allocated to the first wireless power receiver and the second control error value is received from a second wireless power receiver in a second time duration which is allocated to the second wireless power receiver.

2. The method of claim 1 , wherein the control error corresponding to each of the plurality of wireless power receivers is generated based on at least one of a value obtained by subtracting an actually received amount of power from a target amount of power corresponding to each of the plurality of wireless power receivers, a value obtained by subtracting an actually received receiving side voltage from a target receiving side voltage corresponding to each of the plurality of wireless power receivers, a value obtained by subtracting an actually received receiving side current from a target receiving side current corresponding to each of the plurality of wireless power receivers, a value obtained by subtracting transmission efficiency upon actually receiving power in a wireless manner from a target transmission efficiency corresponding to each of the plurality of wireless power receivers, and a value obtained by subtracting a transmission gain upon actually receiving power in a wireless manner from a target transmission gain corresponding to each of the plurality of wireless power receivers.

3. The method of claim 2 , wherein the transmission efficiency is a ratio between transmission power of the wireless power transmitter and reception power corresponding to each of the plurality of wireless power receivers,
wherein the transmission gain is a ratio between a transmitting side voltage corresponding to the wireless power transmitter and a receiving side voltage corresponding to each of the plurality of wireless power receivers, and
wherein the reception power is detected based on a receiving side voltage and a receiving side current corresponding to each of the plurality of wireless power receivers.

4. The method of claim 1 , wherein each of the plurality of wireless power receivers transmits a packet to the wireless power transmitter, the packet including a power control message,
wherein the control error is transmitted to the wireless power transmitter by being included in the packet, the packet including the power control message, and
wherein the packet including the power control message is generated by modulating the wireless power signal by each of the plurality of wireless power receivers.

5. The method of claim 1 , wherein the transmission parameter is at least one of a frequency, an amplitude and a phase of the wireless power signal, and a time interval for transmission of the wireless power signal.

6. The method of claim 1 , wherein the transmission parameter is a transmission frequency corresponding to each of the plurality of wireless power receivers,
wherein the transferring of the power in the wireless manner based on the detected transmission parameters comprises:
periodically changing the frequency of the wireless power signal to a transmission frequency corresponding to each of the plurality of wireless power receivers; and
transferring power in the wireless manner by forming the wireless power signal using the periodically changed transmission frequency.

7. The method of claim 1 , wherein the transferring of the power in the wireless manner based on the detected transmission parameters comprises:
detecting an optimal transmission parameter corresponding to the plurality of wireless power receivers based on the detected transmission parameters; and
transferring power in the wireless manner to the plurality of wireless power receivers by forming the wireless power signal based on the optimal transmission parameter.

8. The method of claim 7 , wherein the optimal transmission parameter is generated by processing the detected transmission parameters in a statistical manner.

9. The method of claim 8 , wherein the statistical manner is a method based on at least one of an average, variance and standard deviation of the transmission parameters.

10. The method of claim 1 , wherein the transmission parameter is a transmission frequency corresponding to each of the plurality of wireless power receivers,
wherein the transferring of the power in the wireless manner based on the detected transmission parameters comprises:
setting a weight for each of the plurality of wireless power receivers based on the control errors or the detected transmission parameters;
setting a transmission time interval for each of the plurality of wireless power receivers based on the weights; and
transferring power in the wireless manner by forming the wireless power signal having the transmission frequency corresponding to each of the plurality of wireless power transmitters for the set transmission time interval.

11. The method of claim 1 , wherein the transmission parameters are detected based on a first weight and a second weight proportional to the first control error value and the second control error value.

12. The method of claim 1 , wherein the transmission parameter is decided as a value that the control error of each of the plurality of wireless power receivers is less than a reference value.

13. The method of claim 1 , wherein the transmission parameter is decided as a value that a control error value of a specific wireless power receiver of the plurality of wireless power receivers does not increase more than a specific value.

14. The method of claim 1 , wherein the transmission parameter is decided based on at least one of whether or not a damage is caused on the plurality of wireless power receivers or whether or not the plurality of wireless power receivers are able to wirelessly receive power from the wireless power transmitter.

15. The method of claim 1 , further comprising transmitting a control error transmission request to each of the plurality of wireless power receivers.

16. The method of claim 15 , wherein the control error transmission request is transmitted when the control error is more than a reference value, when a new wireless power receiver is placed in a specific area, when the number of wireless power receivers existing in the specific area changes, when a position of at least one wireless power receiver existing in the specific area changes, and when there is a periodically received request or a request received from the wireless power receiver,
wherein the specific area is an area through which the wireless power signal passes or an area on which the wireless power receiver is sensed.

17. The method of claim 1 , wherein each of the plurality of wireless power receivers transmits the control error to the wireless power transmitter via each time slot c

Assignees

• Lee Jaesung
• Lee Hyunbeom
• Lee Jun
• Seo Jeongkyo
• Lg Electronics Inc

Inventors

• Lee Jaesung
• Lee Hyunbeom
• Lee Jun
• Seo Jeongkyo

Classifications

• H02J2105/44

  Portable electronic devices · CPC title

• H02J7/485

  with provisions for charging different types of batteries · CPC title

• H02J7/96

  in response to battery voltage · CPC title

• H02J7/50

  acting upon multiple batteries simultaneously or sequentially · CPC title

• H02J7/44

  between battery management systems and power sources · CPC title