APPARATUS AND METHOD FOR CHARGE CONTROL IN WIRELESS CHARGING SYSTEM

• US 20140152251A1
• Filed: 11/25/2013
• Published: 06/05/2014
• Est. Priority Date: 11/26/2012
• Status: Active Grant

• Current Assignee: Industry-University Cooperation Foundation Hanyang University, Samsung Electronics Co. Ltd.
• Original Assignee: Industry-University Cooperation Foundation Hanyang University, Samsung Electronics Co. Ltd.
• Inventors: KIM, Dong Zo, KWON, Sang Wook, KIM, Ki Young, KIM, Nam Yun, MOON, Young Jin, PARK, Yun Kwon, SONG, Keum Su, AHN, Chi Hyung, RYU, Young Ho, YOO, Chang Sik, YOON, Chang Wook, CHOI, Jin Sung
• Granted Patent: US 9,793,740 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• 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: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters

Abstract

An apparatus and a method for charge control are provided. The apparatus for charge control may include an integrated direct current-to-direct current (DC/DC) converter configured to step up an output voltage level of a load to be greater than or equal to a supply voltage level set in a power amplifier, and the power amplifier configured to convert a direct current (DC) voltage stepped up by the integrated DC/DC converter into an alternating current (AC) voltage based on a resonant frequency, and to amplify the converted AC voltage. The apparatus for charge control may include a rectification unit configured to convert an AC power received wirelessly into a DC power; and a DC/DC converter configured to step down a voltage level of the DC power to a voltage level required by a load in the receiving mode.

Claims

1. An apparatus for charge control, the apparatus comprising:

an integrated direct current-to-direct current (DC/DC) converter configured to step up an output voltage level of a load to be greater than or equal to a supply voltage level set in a power amplifier in a transmitting mode; and

the power amplifier configured to convert a direct current (DC) voltage stepped up by the integrated DC/DC converter into an alternating current (AC) voltage based on a resonant frequency, and to amplify the converted AC voltage, in the transmitting mode.

2. The apparatus of claim 29, wherein the integrated DC/DC converter comprises:

a first capacitor connected in parallel to at least one of the AC/DC converter and the power amplifier;

a second capacitor connected in parallel to the load;

a first transistor of a P-channel metal oxide semiconductor (PMOS) type, the first transistor connected in series to the first capacitor;

a second transistor of an N-channel metal oxide semiconductor (NMOS) type, the second transistor connected in parallel to the first transistor;

an inductor connected in series to the second transistor; and

an output voltage determining unit configured to determine a voltage applied to the second capacitor to be an output voltage of the integrated DC/DC converter in the receiving mode, and to determine a voltage applied to the first capacitor to be an output voltage of the integrated DC/DC converter in the transmitting mode.

3. The apparatus of claim 2, wherein the integrated DC/DC converter further comprises:

a driving voltage determining unit configured to compare a voltage applied to the second capacitor to a voltage applied to the first capacitor and determine a higher voltage to be a driving voltage of the output voltage determining unit.

4. The apparatus of claim 2, further comprising:

a third switch unit configured to connect the AC/DC converter to the integrated DC/DC converter in the receiving mode to charge the load with a power, and connect the integrated DC/DC converter to the power amplifier in the transmitting mode to transmit the power stored in the load.

5. The apparatus of claim 2, further comprising:

a controller configured to control an operating time of the first transistor based on a difference between a voltage required by the load and a voltage applied to the second capacitor in the receiving mode.

6. The apparatus of claim 5, wherein the controller is configured to control the operating time of the first transistor based on a difference between a supply voltage set in the power amplifier and a voltage applied to the first capacitor.

7. The apparatus of claim 29, wherein the load comprises:

a battery charger configured to charge a battery by storing the DC voltage stepped down by the integrated DC/DC converter;

the battery configured to be charged by the battery charger in the receiving mode, and to transfer a DC voltage to the integrated DC/DC converter in the transmitting mode; and

a first switch unit configured to connect the battery charger to the battery in the receiving mode, and to break the connection between the battery charger and the battery and connect the integrated DC/DC converter to the battery in the transmitting mode.

8. The apparatus of claim 29, further comprising:

a resonator configured to receive the AC power with a wireless power transmitter in the receiving mode, and to transmit the AC power amplified by the power amplifier with a wireless power receiver in the transmitting mode.

9. The apparatus of claim 8, further comprising:

a second switch unit configured to connect the resonator to the AC/DC converter in the receiving mode, and to break the connection between the resonator and the AC/DC converter and connect the resonator to the power amplifier in the transmitting mode.

29. The apparatus of claim 1, further comprising:

an alternating current-to-direct current (AC/DC) converter configured to convert an AC power received wirelessly into the DC power, in a receiving mode; and

wherein the integrated DC/DC converter is further configured to step down a voltage level of the DC power to a voltage level required by the load in the receiving mode.

10. An apparatus for charge control the apparatus comprising:

a rectification unit configured to convert an alternating current (AC) power received wirelessly into a direct current (DC) power, in a receiving mode;

a first DC-to-DC (DC/DC) converter configured to step down a voltage level of the DC power to a voltage level required by a load in the receiving mode;

a second DC/DC converter configured to step up an output voltage level of the load to be greater than or equal to a supply voltage level set in a power amplifier in a transmitting mode; and

the power amplifier configured to convert the DC voltage stepped up by the second DC/DC converter into an AC voltage based on a resonant frequency, and to amplify the converted AC voltage, in the transmitting mode.

11. The apparatus of claim 10, further comprising:

a resonator configured to receive the AC power with a wireless power transmitter in the receiving mode, and to transmit the AC power amplified by the power amplifier with a wireless power receiver in the transmitting mode;

a first switch unit configured to connect the resonator to the rectification unit in the receiving mode, and to connect the resonator to the power amplifier in the transmitting mode;

a second switch unit configured to connect the load to the second DC/DC converter in the transmitting mode; and

a controller configured to control operations of the first switch unit and the second switch unit, based on a user input.

12. The apparatus of claim 10, wherein the load comprises:

a battery charger configured to charge a battery by storing the DC voltage stepped down by the first DC/DC converter; and

the battery configured to be charged by the battery charger in the receiving mode, and to transfer a DC voltage to the second DC/DC converter in the transmitting mode.

13. A method for charge control, the method comprising:

converting an alternating current (AC) power received wirelessly into a direct current (DC) power, in a receiving mode;

stepping down a voltage level of the DC power to a voltage level required by a load, using an integrated direct current-to-direct current (DC/DC) converter in the receiving mode;

stepping up an output voltage level of the load to be greater than or equal to a supply voltage level set in a power amplifier, using the integrated DC/DC converter in a transmitting mode; and

converting the stepped up output voltage level into an AC voltage based on a resonant frequency, and amplifying the converted AC voltage, in the transmitting mode.

14. The method of claim 13, further comprising:

determining one of the receiving mode and the transmitting mode for an apparatus for charge control in a wireless charging system, based on a user input.

15. The method of claim 13, wherein the stepping down comprises determining a voltage applied to the load to be an output voltage of the integrated DC/DC converter in the receiving mode.

16. The method of claim 15, wherein the stepping up comprises determining a voltage applied to the power amplifier to be an output voltage of the integrated DC/DC converter in the transmitting mode.

17. The method of claim 13, further comprising:

receiving the AC power through a mutual resonance between a resonator and a wireless power transmitter in the receiving mode; and

transmitting the AC power amplified by the power amplifier through a mutual resonance between the resonator and a wireless power receiver in the transmitting mode.

18. An apparatus for charge control, the apparatus comprising:

a resonator configured to receive a power a receiving mode, transmit the power in a transmitting mode, and transfer an input power to another terminal by reflecting the input power in a relay mode;

an integrated direct current-to-direct current (DC/DC) converter configured to step down a voltage level of a direct current (DC) signal output from an alternating current-to-direct current (AC/DC) converter to a voltage level required by a load in the receiving mode, and to step up a voltage level output from the load to be greater than or equal to a supply voltage level set in a power amplifier in the transmitting mode; and

a controller configured to control the apparatus for charge control to operate in one of the receiving mode, the transmitting mode, and the relay mode, and increase an input impedance of the resonator to be greater than or equal to a predetermined value.

19. The apparatus of claim 18, wherein the controller is configured to open the resonator by connecting the resonator to the AC/DC converter in the receiving mode, connecting the resonator to the power amplifier in the transmitting mode, and connecting the resonator to an open port in the relay mode using a switch.

20. The apparatus of claim 18, wherein the controller is configured to open the resonator by controlling the integrated DC/DC converter for a supply voltage of “

0”

volts to be supplied to the power amplifier in the relay mode.

21. An apparatus for charge control, the apparatus comprising:

a resonator configured to receive a power in a receiving mode, and reflect an input power in a relay mode;

a direct current-to-direct current (DC/DC) converter configured to step down a voltage level of a direct current (DC) signal output from an alternating current-to-direct current (AC/DC) converter to a voltage level required by a load in the receiving mode; and

a controller configured to control the apparatus for charge control to operate in one of the receiving mode, a transmitting mode, and the relay mode, and increase an input impedance of the resonator to be greater than or equal to a predetermined value.

22. The apparatus of claim 21, wherein the controller is configured to open the resonator by connecting the resonator to the AC/DC converter in the receiving mode, and connecting the resonator to an open port in the relay mode using a switch.

23. The apparatus of claim 21, wherein the controller is configured to control the apparatus for charge control to operate in the relay mode when charging of the load is completed.

24. An apparatus for charge control, the apparatus comprising:

a resonator configured to transmit a power in a transmitting mode, and reflect an input power in a relay mode;

a direct current-to-direct current (DC/DC) converter configured to step up a voltage level output from a load to be greater than or equal to a supply voltage level set in a power amplifier in the transmitting mode; and

a controller configured to increase an input impedance of the resonator to be greater than or equal to a predetermined value in the relay mode.

25. The apparatus of claim 24, wherein the controller is configured to open the resonator by connecting the resonator to the power amplifier, and connecting the resonator to an open port in the relay mode using a switch.

26. The apparatus of claim 24, wherein the controller is configured to open the resonator by controlling the DC/DC converter for a supply voltage of “

0”

volts to be supplied to the power amplifier in the relay mode.

27. The apparatus of claim 24, wherein the controller is configured to control the apparatus for charge control to operate in the relay mode based on a user input.

28. (canceled)