METHOD AND POWER TRANSMITTER FOR CONTROLLING POWER TRANSMISSION AGAINST OVERVOLTAGE AT POWER RECEIVER

• US 20130342161A1
• Filed: 06/20/2013
• Published: 12/26/2013
• Est. Priority Date: 06/20/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: BYUN, Kang-Ho, LEE, Kyung-Woo, KWON, Hyuk-Choon, KIM, Nam-Yun, JUNG, Hee-Won
• Granted Patent: US 10,135,283 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• 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: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers

Abstract

Methods and apparatus are provided for controlling power transmission in a power transmitter against overvoltage at a power receiver. The power transmitter receives a subscription request to subscribe to a wireless power network, from the power receiver. It is determined whether power transmission is available for the power receiver. The power receiver is informed that the power transmission is beginning, when the power transmission is available. The transmission power is increased and transmitted. It is determined whether a stop request to stop increasing voltage is received at the power transmitter from the power receiver. The increase of the transmission power is stopped when the stop request is received at the power transmitter. Charging of the power receiver is started by transmitting a start charging command from the power transmitter to the power receiver.

Claims

1. A method of controlling power transmission in a power transmitter against overvoltage at a power receiver, the method comprising the steps of:

receiving, at the power transmitter, a subscription request to subscribe to a wireless power network, from the power receiver;

determining whether power transmission is available for the power receiver;

informing the power receiver that the power transmission is beginning, when the power transmission is available;

increasing and transmitting the transmission power;

determining whether a stop request to stop increasing voltage is received at the power transmitter from the power receiver;

stopping the increase of the transmission power when the stop request is received at the power transmitter; and

starting charging of the power receiver by transmitting a start charging command from the power transmitter to the power receiver.

2. The method of claim 1, wherein informing the power receiver that the power transmission is beginning comprises, transmitting a notification frame that comprises information indicating that the power transmission is beginning

3. The method of claim 2, wherein the information indicating that the power transmission is beginning is set up in a status field in the notification frame.

4. The method of claim 1, wherein the subscription request comprises at least one of piece of power information, which includes an identifier (ID) of the power receiver, a protocol version for communication, minimum and maximum voltages of the power receiver, and a reference output voltage and a reference output current of the power receiver.

5. The method of claim 4, wherein determining whether power transmission is available for the power receiver is based on the reference output voltage and the reference output current from among the pieces of the power information.

6. The method of claim 1, wherein increasing and transmitting the transmission power comprises, increasing and transmitting the transmission power in phases after informing the power receiver that the power transmission is beginning

7. The method of claim 6, wherein a length of a phase is calculated based on a reference output voltage and a reference output current included in power information of the power receiver.

8. The method of claim 1, further comprising maintaining a current level of the transmission power, when the stop request is received.

9. The method of claim 1, wherein, when there is at least one other power receiver in addition to the power receiver, informing the at least one other power receiver that the power transmission is beginning for the power receiver.

10. The method of claim 1, wherein, when there is at least one other power receiver in addition to the power receiver, stopping the increase of the transmission power and informing the power receiver and the at least one other power receiver that an operation of increasing the transmission power is stopped.

11. The method of claim 1, further comprising:

determining whether a load change is detected in a predetermined period;

transmitting power to drive the power receiver, when the load change is detected;

receiving a search request from the power receiver in response to transmitting the power to the power receiver; and

after receiving a reply for the search request, receiving the subscription request from the power receiver.

12. A power transmitter for controlling power transmission against overvoltage at a power receiver, the power transmitter comprising:

a wireless communication unit for receiving a subscription request to subscribe to a wireless power network from the power receiver;

a resonant signal generator for supplying transmission power to the power receiver under control of the controller; and

a controller for determining whether power transmission is available for the power receiver, informing the power receiver through the wireless communication unit that power transmission is beginning when the power transmission is available, increasing and transmitting the transmission power using the resonant signal generator, determining whether a stop request to stop increasing voltage is received from the power receiver through the wireless communication unit, stopping the increase of the transmission power when the stop request is received, and starting charging of the power receiver by transmitting a start charging command to the power receiver through the wireless communication unit.

13. The power transmitter of claim 12, wherein the controller transmits a notification frame that comprises information indicating that the power transmission is beginning through the wireless communication unit.

14. The power transmitter of claim 13, wherein the information indicating that the power transmission is beginning is set up in a status field in the notification frame.

15. The power transmitter of claim 12, wherein the subscription request comprises at least one of piece of power information, which includes an identifier (ID) of the power receiver, a protocol version for communication, minimum and maximum voltages of the power receiver, and a reference output voltage and a reference output current of the power receiver.

16. The power transmitter of claim 15, wherein the controller determines whether the power transmission is available for the power receiver based on the reference output voltage and the reference output current from among the pieces of the power information.

17. The power transmitter of claim 12, wherein the controller increases and transmits the transmission power in phases after informing the power receiver that the power transmission is beginning

18. The power transmitter of claim 17, wherein a length of a phase is calculated based on a reference output voltage and a reference output current included in power information of the power receiver.

19. The power transmitter of claim 12, wherein, when there is at least one other power receiver that is performing charging in addition to the power receiver, the controller informs the at least one other power receiver that the power transmission is beginning for the power receiver.

20. The power transmitter of claim 12, wherein, when there is at least one other power receiver that is performing charging in addition to the power receiver, the controller stops increasing the transmission power and informs the power receiver and the at least one other power receiver that an operation of increasing the transmission power is stopped.