Low-Power Wireless Charging Apparatus And Method Thereof

• US 20130082647A1
• Filed: 09/07/2012
• Published: 04/04/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Wit Co., Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: KIM, Eung Ju, YOON, Young Seok
• Granted Patent: US 9,231,428 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• 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 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source

Abstract

Disclosed herein is a low-power wireless charging apparatus including: a plurality of primary coils corresponding to a plurality of receivers, respectively; a plurality of drivers periodically and sequentially transmitting receiver detect signals; a sensing unit detecting a current and a voltage according to a magnetic field changed by one or more of the plurality of primary coils; a comparator comparing the detected current and voltage with pre-set values; a low-power auxiliary control unit generating a wake-up signal when one or more receivers are present; and a main control unit turned on upon receiving the wake-up signal, and controlled to generate a wireless power signal for charging a corresponding receiver and transmit, whereby unnecessary power consumption can be prevented and the burden of the main control unit can be lessened, thus increasing efficiency.

Claims

1. A low-power wireless charging apparatus comprising:

a plurality of primary coils;

a plurality of drivers periodically and sequentially transmitting receiver detect signals for detecting receivers connected to the plurality of primary coils, respectively;

a sensing unit detecting a current and a voltage according to a magnetic field changed by one or more of the plurality of primary coils by the receiver detect signals transmitted through the plurality of drivers;

a comparator comparing the current and voltage detected by the sensing unit with pre-set values;

a low-power auxiliary control unit generating a wake-up signal when one or more receivers are present; and

a main control unit turned on upon receiving a wake-up signal generated by the low-power auxiliary control unit, and controlled to generate a wireless power signal for charging a corresponding receiver and transmit the generated wireless power signal.

2. The apparatus as set forth in claim 1, wherein the low-power auxiliary control unit includes:

an auxiliary control signal generator generating respective receiver detect signals to be transmitted through the plurality of drivers, respectively; and

a low-power controller controlling the auxiliary control signal generator and the plurality of drivers to periodically and sequentially transmit the respective receiver detect signals generated by the auxiliary control signal generator through the plurality of drivers, controlling the sensing unit to detect a current and a voltage according to a magnetic field changed by one or more of the plurality of primary coils according to the respective receiver detect signals, and controlling the comparator to compare the detected current and voltage with pre-set values, and generate a wake-up signal including driver information and primary coil information corresponding to the detected current and voltage and transmit the generated wake-up signal to the main control unit when the detected current and voltage are greater than the pre-set values.

3. The apparatus as set forth in claim 1, wherein the main control unit includes:

a main control signal generator generating a wireless power signal to be transmitted through a corresponding driver according to the driver information and the primary coil information included in the wake-up signal received from the low-power auxiliary control unit; and

a main controller controlling the main control signal generator and the corresponding driver to transmit the wireless power signal generated by the main control signal generator through the corresponding driver, and controlled to transmit the wireless power signal to a corresponding receiver through a primary coil connected with the corresponding driver.

4. The apparatus as set forth in claim 3, wherein the main controller transmits an authentication signal for authenticating the corresponding receiver through the corresponding driver and the primary coil and then determines whether or not a response signal transmitted from the corresponding receiver is received, and when the response signal is received, the main controller is controlled to transmit the wireless power signal.

5. The apparatus as set forth in claim 1, wherein the plurality of drivers include:

a first driver transmitting the wireless power signal generated under the control of the main control unit through a corresponding primary coil among the plurality of primary coils; and

a second driver periodically and sequentially transmitting the respective receiver detect signals generated under the control of the low-power auxiliary control unit through the plurality of primary coils.

6. The apparatus as set forth in claim 5, further comprising:

a switching unit installed between the plurality of drivers and the plurality of primary coils to perform switching to connect the plurality of drivers and the plurality of primary coils under the control of the main control unit and the low-power auxiliary control unit.

7. The apparatus as set forth in claim 6, wherein the switching unit includes:

a first switch switched to connect the first driver and the plurality of primary coils; and

a second switch switched to connect the second driver and the plurality of primary coils.

8. A low-power wireless charging method comprising:

(A) generating, by a low-power auxiliary control unit, receiver detect signals corresponding to a plurality of primary coils to determine whether or not a receiver is present, and generating a wake-up signal when one or more receives are present; and

(B) turning on a main control unit by receiving the generated wake-up signal to generate a wireless power signal for charging a corresponding receiver and transmit the generated wireless power signal.

9. The method as set forth in claim 8, further comprising:

(C) transmitting the wireless power signal to charge the corresponding receiver, and changing the main control unit into a sleep mode when the charging of the corresponding receiver is completed.

10. The method as set forth in claim 8, wherein the operation (A) includes:

(A-1) generating, by the low-power auxiliary control unit, respective receiver detect signals for detecting respective receivers corresponding to the plurality of primary coils;

(A-2) transmitting the generated respective receiver detect signals through a plurality of drivers connected to the plurality of primary coils, respectively;

(A-3) detecting a current and a voltage according to a magnetic field changed by one or more of the plurality of primary coils according to the respective receiver detect signals transmitted through the plurality of drivers;

(A-4) comparing the detected current and voltage with pre-set values to determine whether or not the detected current and voltage are greater than the pre-set values; and

to (A-5) generating a wake-up signal when the detected current and voltage are greater than the pre-set values.

11. The method as set forth in claim 8, wherein the operation (B) includes:

(B-1) turning on the main control unit by receiving the wake-up signal;

(B-2) generating a wireless power signal for charging the corresponding receiver; and

(B-3) transmitting the generated wireless power signal to a driver corresponding to the corresponding receiver to transmit the wireless power signal to the corresponding receiver through a primary coil connected to the driver.