WIRELESS POWER TRANSMITTER, METHOD OF CONTROLLING THE SAME, AND TEMPERATURE COMPENSATION METHOD FOR LOAD VALUE OF THE WIRELESS POWER TRANSMITTER

• US 20140015333A1
• Filed: 07/10/2013
• Published: 01/16/2014
• Est. Priority Date: 07/10/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: BYUN, Kang-Ho, HAN, Seung-Woo, KIM, Hong-Kweun
• Granted Patent: US 9,502,172 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• 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

Abstract

A wireless power transmitter, which detects a load change in a wireless power transmission, includes a power supply unit, a power converter which converts the driving power supplied from the power supply unit into Alternating Current, a power transmitter which wirelessly transmits the converted driving power to the wireless power transmitter, a temperature measurement unit which measures a temperature of the wireless power transmitter; and a controller which detects a current and load value of the driving power output from the power supply unit, compensates for the load value based on the measured temperature value, and determines a load change of the power transmitter based on the compensated load value.

Claims

1. A wireless power transmitter for detecting a load change in a wireless power transmission, the wireless power transmitter comprising:

a power supply unit which supplies a driving power of the wireless power transmitter;

a power converter which converts the driving power supplied from the power supply unit into Alternating Current (AC) form;

a power transmitter which wirelessly transmits the converted driving power to the wireless power transmitter;

a temperature measurement unit which measures a temperature value of at least one portion of the wireless power transmitter; and

a controller which detects a current value and a load value of the driving power output from the power supply unit, compensates for the load value based on the measured temperature value, and determines a load change of the power transmitter based on the compensated load value.

2. The wireless power transmitter of claim 1, wherein the controller detects a change in the number of the at least one wireless power receiver based on the load change.

3. The wireless power transmitter of claim 1, further comprising a storage unit which stores a temperature compensation constant for a linear relationship between a temperature value and a load value.

4. The wireless power transmitter of claim 3, wherein the controller measures a reference value, which is a load value when there is no wireless power receiver for receiving electric power from the wireless power transmitter.

5. The wireless power transmitter of claim 4, wherein the storage unit stores a temperature compensation reference load value, which is a reference load value for a preset temperature, and the controller determines an offset between the temperature compensation reference load value and the reference load value.

6. The wireless power transmitter of claim 5, wherein the controller determines the compensated load value based on the load value and the offset.

7. The wireless power transmitter of claim 2, wherein the controller determines a change in a number of the wireless power receivers based on the compensated load value.

8. A method of controlling a wireless power transmitter for detecting a change in a load change of wireless power transmission, the method comprising:

supplying a driving power of the wireless power transmitter;

converting the driving power into Alternating Current (AC) form;

wirelessly transmitting the converted driving power to at least one wireless power receiver;

detecting a current value and a load value of the driving power;

measuring a temperature value of at least one portion of the wireless power transmitter;

compensating the load value based on the measured temperature value; and

determining a wireless power transmission state of the power transmitter based on the compensated load value.

9. The method of claim 8, wherein the wireless power transmission state corresponds to a number of the at least one wireless power receiver.

10. The method of claim 8, further comprising storing a temperature compensation constant for a linear relationship between a temperature value and a load value.

11. The method of claim 10, wherein when compensating for the load value, a reference load value, which is a load value when there exists no wireless power receiver, is determined.

12. The method of claim 11, further comprising storing a temperature compensation reference load value, which is a reference load value for a preset temperature, wherein when compensating for the load value based on the measured temperature value, an offset between the temperature compensation reference load value and the reference load value is determined.

13. The method of claim 12, wherein when compensating for the load value based on the measured temperature value, the compensated load value is determined based on the load value and the offset.

14. The method of claim 9, wherein when determining the wireless power transmission state, a change in the number of the at least one wireless power receiver is determined based on the compensated load value.

15. A temperature compensation method for a load value of a wireless power transmitter for wirelessly transmitting electric power to a wireless power receiver, the method comprising:

measuring a reference load value, which is a load value of the wireless power transmitter when there exists no wireless power receiver;

measuring a temperature of a portion of the wireless power transmitter;

reading out a temperature compensation constant for a linear relationship between a temperature value and a load value;

determining a temperature compensation reference load value, which is a reference load value for a preset temperature, based on the temperature, the temperature compensation constant, and the reference load value;

determining an offset between the temperature compensation reference value and the reference load value; and

compensating for the load value based on the offset.