METHOD AND APPARATUS FOR CONTROLLING WIRELESS INDUCTION POWER SUPPLY

• US 20140306548A1
• Filed: 04/11/2014
• Published: 10/16/2014
• Est. Priority Date: 04/12/2013
• Status: Active Grant

• Current Assignee: Semiconductor Components Industries LLC (ON Semiconductor Corporation)
• Original Assignee: System General Corporation (ON Semiconductor Corporation)
• Inventors: YANG, TA-YUNG
• Granted Patent: US 10,298,073 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: G01V 3/102 by measuring amplitude
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings

Abstract

The present invention provides a method and an apparatus for controlling the wireless induction power supply. The apparatus comprises a transmitter control circuit and a receiver control circuit. The method comprises generating a plurality of switching signals for switching a transmitter winding and generating a power; detecting a level of a transmitter signal from the transmitter winding; and controlling a switch to deliver the power from a receiver winding to a load. The receiver winding is coupled to receive the power from the transmitter winding. The switching signals will be disabled if the level of the transmitter signal is not higher than a threshold over a first period or the level of the transmitter signal is higher than a high-threshold over a second period. Accordingly, the method and the apparatus according to the present invention have the foreign object detection (FOD) function for the safety.

Claims

1. A method for controlling a wireless induction power supply, comprising:

generating a plurality of switching signals for switching a transmitter winding and generating a power;

detecting a level of a transmitter signal from the transmitter winding; and

controlling a switch to deliver the power from a receiver winding to a load;

wherein the receiver winding is coupled to receive the power from the transmitter winding;

the switching signals will be disabled if the level of the transmitter signal is not higher than a threshold over a first period.

2. The method as claimed in claim 1, wherein the switching signals will be enabled periodically to detect the level of the transmitter signal if the switching signals are disabled when the level of the transmitter signal is not higher than the threshold over the first period.

3. The method as claimed in claim 1, wherein the switching signals will be coupled to drive a plurality of transistors coupled to the transmitter winding;

the transistors develop a bridge topology to switch the transmitter winding.

4. The method as claimed in claim 1, wherein the switching signals will be disabled if the level of the transmitter signal is higher than a high-threshold over a second period.

5. The method as claimed in claim 4, wherein the switching signals will be enabled periodically to detect the level of the transmitter signal if the switching signals are disabled when the level of the transmitter signal is higher than the high-threshold over the second period.

6. The method as claimed in claim 1, further comprising:

detecting a level of an input voltage of the wireless induction power supply.

7. The method as claimed in claim 1, wherein the switch is periodically turned off.

8. The method as claimed in claim 1, wherein the level of the transmitter signal is related to a level of an input voltage of the wireless induction power supply and an impedance of the transmitter winding, the impedance of the transmitter winding becomes lower and the level of the transmitter signal is decreased when a foreign object is coupled to the transmitter winding by a magnetic field of the transmitter winding.

9. The method as claimed in claim 1, wherein the switch is turned off when the load condition of the load is a no load condition.

10. A method for controlling a wireless induction power supply, comprising:

generating a plurality of switching signals for switching a transmitter winding and generating a power;

detecting a level of a transmitter signal from the transmitter winding; and

controlling a switch to deliver the power from a receiver winding to a load;

wherein the receiver winding is coupled to receive the power from the transmitter winding;

the switching signals will be disabled if the level of the transmitter signal is higher than a high-threshold over a period.

11. The method as claimed in claim 10, wherein the switching signals will be enabled periodically to detect the level of the transmitter signal if the switching signals are disabled when the level of the transmitter signal is higher than the high-threshold over the period.

12. The method as claimed in claim 10, wherein the switching signals will be coupled to drive a plurality of transistors coupled to the transmitter winding;

the transistors develop a bridge topology to switch the transmitter winding.

13. The method as claimed in claim 10, wherein the switching signals will be disabled if the level of the transmitter signal is not higher than a low-threshold over an over-load period.

14. The method as claimed in claim 13, wherein the switching signals will be enabled periodically to detect the level of the transmitter signal if the switching signals are disabled when the level of the transmitter signal is not higher than the low-threshold over the over-load period.

15. The method as claimed in claim 10, further comprising:

detecting the level of an input voltage of the wireless induction power supply.

16. The method as claimed in claim 10, wherein the switch is periodically turned off.

17. The method as claimed in claim 10, wherein the level of the transmitter signal is related to a level of an input voltage of the wireless induction power supply and an impedance of the transmitter winding, the impedance of the transmitter winding becomes lower and the level of the transmitter signal is decreased when a foreign object is coupled to the transmitter winding by a magnetic field of the transmitter winding.

18. The method as claimed in claim 10, wherein the switch is turned off when the load condition of the load is a no load condition.

19. An apparatus of controlling a wireless induction power supply, comprising:

a transmitter control circuit generating a plurality of switching signals for switching a transmitter winding and generating a power, and detecting a level of a transmitter signal from the transmitter winding; and

a receiver control circuit controlling a switch to deliver the power from a receiver winding to a load;

wherein the receiver winding is coupled to receive the power from the transmitter winding;

the switching signals will be disabled if the level of the transmitter signal is not higher than a threshold over a first period or the level of the transmitter signal is higher than a high-threshold over a second period.