WIRELESS POWER TRANSMISSION APPARATUS AND METHOD AND WIRELESS POWER RECEPTION APPARATUS

• US 20140084858A1
• Filed: 09/12/2013
• Published: 03/27/2014
• Est. Priority Date: 09/12/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Nam Yun, Kwon, Sang Wook, Kim, Ki Young, Park, Yun Kwon, Ahn, Chi Hyung
• Granted Patent: US 9,502,923 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• 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 7/007 Regulation of charging or discharging current or voltage

Abstract

A wireless power transmission apparatus includes a measurer configured to measure a value of a current flowing in a source resonator, a communication unit configured to receive a value of a charging current of a battery from a wireless power reception apparatus, and a power controller configured to control an amount of power to be transmitted by the source resonator based on either one or both of the value of the current measured by the measurer and the value of the charging current received by the communication unit. The value of the charging current of the battery varies as the battery is charged.

Claims

1. A wireless power transmission apparatus comprising:

a measurer configured to measure a value of a current flowing in a source resonator;

a communication unit configured to receive a value of a charging current of a battery from a wireless power reception apparatus; and

a power controller configured to control an amount of power to be transmitted by the source resonator based on either one or both of the value of the current measured by the measurer and the value of the charging current received by the communication unit;

wherein the value of the charging current of the battery varies as the battery is charged.

2. The apparatus of claim 1, wherein the power controller comprises:

a charging mode determiner configured to determine a charging mode of the battery based on a change in the value of the charging current received by the communication unit; and

a pulse signal generator configured to generate a pulse signal having a pulse width adjusted based on the determined charging mode of the battery.

3. The apparatus of claim 2, wherein the charging mode determiner is further configured to determine whether the charging mode of the battery is a constant current (CC) mode in which the value of the charging current of the battery is constant, or a constant voltage (CV) mode in which the value of the charging current of the battery is variable and a value of a charging voltage of the battery is constant.

4. The apparatus of claim 2, further comprising:

an alternating current-to-direct current (AC/DC) converter configured to convert an AC power supplied from a power supply to a DC power based on the pulse width of the pulse signal; and

a DC-to-AC (DC/AC) converter configured to convert the DC power to an AC power based on a resonant frequency of the source resonator.

5. The apparatus of claim 1, wherein the communication unit is further configured to receive, from the wireless power reception apparatus, a value of a current flowing in a target resonator;

and

the power controller comprises;

an offset calculator configured to calculate a power transmission efficiency offset by comparing the value of the current measured by the measurer with the value of the current flowing in the target resonator received by the communication unit, and calculating the power transmission efficiency offset based on a result of the comparing; and

a pulse signal generator configured to generate a pulse signal having a pulse width adjusted based on the calculated power transmission efficiency offset.

6. The apparatus of claim 1, wherein the communication unit is further configured to receive, from the wireless power reception apparatus, a value of a current flowing in a target resonator;

and

the power controller comprises;

a charging mode determiner configured to determine a charging mode of the battery based on a change in the value of the charging current received by the communication unit;

an offset calculator configured to calculate a power transmission efficiency offset by comparing the value of the current measured by the measurer with the value of the current flowing in the target resonator received by the communication unit, and calculating the power transmission efficiency offset based on a result of the comparing; and

a pulse signal generator configured to generate a pulse signal having a pulse width adjusted based on the determined charging mode of the battery and the calculated power transmission efficiency offset.

7. The apparatus of claim 6, further comprising:

a first comparator configured to compare the value of the current measured by the measurer with a reference current value; and

a second comparator configured to compare the value of the current flowing in the target resonator received by the communication unit with the reference current value;

wherein the pulse signal generator is further configured to adjust the pulse width of the pulse signal based on a difference between a result of the comparing by the first comparator and a result of the comparing by the second comparator.

8. The apparatus of claim 1, wherein the communication unit is further configured to receive, from the wireless power reception apparatus, a value of a current flowing in a rectifier as the value of the charging current of the battery.

9. The apparatus of claim 1, wherein the wireless power reception apparatus is configured to receive power from a target resonator;

the source resonator comprises a coil;

the target resonator comprises a coil; and

a ratio of a number of turns of the coil of the source resonator to a number of turns of the coil of the target resonator is a 1;

1 ratio.

10. A wireless power reception apparatus comprising:

a rectifier configured to rectify an alternating current (AC) power received from a wireless power transmission apparatus by a target resonator through a mutual resonance with a source resonator to a direct current (DC) power;

a measurer configured to measure a value of a current flowing in the target resonator; and

a communication unit configured to transmit the value of the current measured by the measurer to the wireless power transmission apparatus.

11. The apparatus of claim 10, wherein the measurer is further configured to measure a value of a current flowing from the rectifier into a battery;

and

the communication unit is further configured to transmit the value of the current flowing into the battery to the wireless power transmission apparatus.

12. The apparatus of claim 11, further comprising a controller configured to determine a charging mode of the battery based on a change in the value of the current flowing into the battery.

13. The apparatus of claim 10, wherein the communication unit is further configured to communicate with the wireless power transmission apparatus using either one or both of an in-band communication scheme using a resonant frequency of the target resonator and an out-band communication scheme using a communication frequency differing from the resonant frequency.

14. A wireless power transmission method comprising:

measuring a value of a current flowing in a source resonator;

receiving a value of a charging current of a battery from a wireless power reception apparatus; and

controlling an amount of power to be transmitted by the source resonator based on either one or both of the measured value of the current and the received value of the charging current;

wherein the value of the charging current of the battery varies as the battery is charged.

15. The method of claim 14, wherein the controlling comprises:

determining a charging mode of the battery based on a change in the received value of the charging current; and

generating a pulse signal having a pulse width adjusted based on the determined charging mode of the battery.

16. The method of claim 15, further comprising:

converting an alternating current (AC) power supplied from a power supply to a direct current (DC) power based on the pulse width of the pulse signal; and

converting the DC power to an AC power based on a resonant frequency of the source resonator.

17. The method of claim 14, wherein the receiving comprises receiving, from the wireless power reception apparatus, a value of a current flowing in a target resonator;

and

the controlling comprises;

calculating a power transmission efficiency offset by comparing the measured value of the current with the received value of the current flowing in the target resonator, and calculating the power transmission efficiency offset based on a result of the comparing; and

generating a pulse signal having a pulse width adjusted based on the calculated power transmission efficiency offset.

18. The method of claim 14, wherein the receiving comprises receiving, from the wireless power reception apparatus, a value of a current flowing in a target resonator;

and

the controlling comprises;

determining a charging mode of the battery based on a change in the received value of the charging current;

calculating a power transmission efficiency offset by comparing the measured value of the current with the received value of the current flowing in the target resonator, and calculating the power transmission efficiency offset based on a result of the comparing; and

generating a pulse signal having a pulse width adjusted based on the determined charging mode of the battery and the calculated power transmission efficiency offset.

19. A wireless power transmission apparatus comprising:

a measurer configured to measure information indicative of an amount of power being transmitted by a source resonator;

a communication unit configured to receive, from a wireless power reception apparatus, measured information indicative of an amount of power being consumed by a load powered by the wireless reception apparatus; and

a controller configured to control an amount of power to be transmitted by the source resonator based on either one or both of the information measured by the measurer and the measured information received by the communication unit.

20. The wireless power transmission apparatus of claim 19, wherein the controller is further configured to control the amount of power to be transmitted by the source resonator based on a difference between the information measured by the measurer and the measured information received by the communication unit.