APPARATUS AND METHOD FOR WIRELESS CHARGING

• US 20140327390A1
• Filed: 01/03/2014
• Published: 11/06/2014
• Est. Priority Date: 05/02/2013
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: PARK, Ji Man, LEE, Kang Bok, BAEK, Kyu-Ha
• Granted Patent: US 9,590,446 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00308 Overvoltage protection

Abstract

A wireless charging apparatus is provided. The wireless charging apparatus includes: an antenna that receives electrical waves; at least two charging power generators that generate charging power for charging a battery using the electrical waves received through the antenna; and a controller that senses a frequency of the electrical waves received through the antenna and that activates one of the at least two charging power generators according to a sensed result.

Claims

1. A wireless charging apparatus, comprising:

an antenna that receives electrical waves;

at least two charging power generators that generate charging power for charging a battery using the electrical waves received through the antenna; and

a controller that senses a frequency of the electrical waves received through the antenna and that activates one of the at least two charging power generators according to a sensed result.

2. The wireless charging apparatus of claim 1, wherein the at least two charging power generators comprise:

a first charging power generator that is activated in response to a first control signal to generate the charging power; and

a second charging power generator that is activated in response to a second control signal to generate the charging power,

wherein the controller activates the first control signal when a frequency of electrical waves received through the antenna corresponds to a first frequency band, and activates the second control signal when a frequency of electrical waves received through the antenna corresponds to a second frequency band lower than the first frequency band.

3. The wireless charging apparatus of claim 2, wherein the first charging power generator comprises:

a first switch that transfers electrical waves received through the antenna, when the first control signal is activated;

a first rectifier that generates DC power by rectifying the electrical waves that are transferred from the first switch; and

a first converter that generates the charging power by adjusting a level of DC power that is output from the first rectifier to correspond to a capacity of the battery, and

the second charging power generator comprises;

a second switch that transfers electrical waves received through the antenna, when the second control signal is activated;

a second rectifier that generates DC power by rectifying the electrical waves transferred from the second switch; and

a second converter that generates the charging power by adjusting a level of DC power output from the second rectifier to correspond to a capacity of the battery.

4. The wireless charging apparatus of claim 3, wherein the first charging power generator further comprises a third switch that transfers charging power that is output from the first converter to the battery, when a third control signal is activated, and

the second charging power generator further comprises a fourth switch that transfers charging power that is output from the second converter to the battery, when a fourth control signal is activated,

wherein the controller senses a charge state of the battery and activates the third control signal and the fourth control signal according to a sensed result.

5. The wireless charging apparatus of claim 4, further comprising:

a first impedance matching unit that performs impedance matching of electrical waves received through the antenna with a first impedance value corresponding to the first frequency band; and

a second impedance matching unit that performs impedance matching of electrical waves received through the antenna with a second impedance value corresponding to the second frequency band,

wherein an output of the first impedance matching unit is transferred to the first switch, and

an output of the second impedance matching unit is transferred to the second switch.

6. The wireless charging apparatus of claim 5, wherein the first impedance matching unit is connected to a first receiving terminal and a second receiving terminal of the antenna,

the second impedance matching unit is connected to the second receiving terminal and a third receiving terminal of the antenna, and

the second receiving terminal of the antenna is formed between the first receiving terminal and the third receiving terminal.

7. The wireless charging apparatus of claim 4, wherein the controller transmits data representing the sensed charge state of the battery to an external transmitting apparatus having transmitted the electrical waves.

8. The wireless charging apparatus of claim 6, wherein the first frequency band is a frequency band for near field communication (NFC) communication, and

the controller determines, when a frequency of electrical waves received through the antenna corresponds to the first frequency band, whether the electrical waves are for the NFC communication according to whether data is loaded in the electrical waves, and if the electrical waves are for the NFC communication, the controller controls to operate an NFC communication module for performing the NFC communication and inactivates the third and fourth control signals regardless of the sensed charge state of the battery.

9. The wireless charging apparatus of claim 8, wherein the NFC communication module is positioned within the wireless charging apparatus.

10. The wireless charging apparatus of claim 8, wherein the first and second charging power generators each comprise:

a clock signal recovery unit that recovers a clock signal of electrical waves received through the antenna and that outputs the clock signal to the controller; and

a modulation unit that modulates data representing the charge state of the battery that is sensed by the controller,

wherein the first charging power generator further comprises a demodulation unit that demodulates data that is loaded in the electrical waves received through the antenna, and that outputs the data to the controller.

11. The wireless charging apparatus of claim 10, wherein the controller comprises a frequency determination unit that divides a frequency of electrical waves having a clock signal that is recovered by the clock signal recovery unit into a predetermined size and that counts a pulse width of the divided frequency with a reference clock signal, and that determines a frequency of electrical waves received through the antenna using the counted value.

12. The wireless charging apparatus of claim 2, wherein the first charging power generator generates the charging power with a resonant method, and

the second charging power generator generates the charging power with a magnetic induction method.

13. The wireless charging apparatus of claim 3, further comprising a limiter that protects a circuit from an overvoltage between the first rectifier and the first switch.

14. The wireless charging apparatus of claim 3, wherein the first converter further comprises an over voltage protection (OVP) circuit.

15. A wireless charging apparatus, comprising:

an antenna that receives electrical waves;

an impedance matching unit that performs impedance matching of the electrical waves received through the antenna with an impedance value;

a charging power generator that generates charging power for charging a battery using electrical waves output from the impedance matching unit; and

a controller that senses a frequency band of the electrical waves received through the antenna and that adjusts the impedance value according to a sensed result.

16. The wireless charging apparatus of claim 15, wherein the impedance matching unit comprises a plurality of capacitors that are turned on/off in response to first control signals and that have capacitance corresponding to the impedance value, and

wherein the controller generates the first control signals according to the sensed result and outputs the first control signals to the impedance matching unit.

17. The wireless charging apparatus of claim 16, wherein the charging power generator comprises:

a rectifier that generates DC power by rectifying electrical waves that are output from the impedance matching unit;

a converter that generates the charging power by adjusting a level of DC power that is output from the rectifier to correspond to a capacity of the battery; and

a switch that transfers charging power output from the converter to the battery when a second control signal is activated,

wherein the controller senses a charge state of the battery and activates the second control signal according to the sensed charge state.

18. The wireless charging apparatus of claim 17, further comprising a near field communication (NFC) module that is activated in response to a third control signal to perform NFC communication,

wherein the controller determines, when a frequency of electrical waves received through the antenna corresponds to a frequency band for the NFC communication, whether the electrical waves are for the NFC communication according to whether data is loaded in the electrical waves, and if the electrical waves are for the NFC communication, the controller activates the third control signal and inactivates the second control signal regardless of the sensed charge state of the battery.

19. The wireless charging apparatus of claim 18, wherein the charging power generator further comprises:

a clock signal recovery unit that recovers a clock signal of electrical waves received through the antenna and that outputs the clock signal to the controller;

a modulation unit that modulates data representing the charge state of the battery that is sensed by the controller; and

a demodulation unit that demodulates data that is loaded in the electrical waves received through the antenna and that outputs the data to the controller.

20. A wireless charging method, comprising:

receiving electrical waves through an antenna;

determining whether a frequency of the received electrical waves corresponds to one of a first frequency band and a second frequency band lower than the first frequency band; and

activating, according to a determined result, one of a first charging power generator that generates charging power for charging a battery using electrical waves of the first frequency band and a second charging power generator that generates the charging power using electrical waves of the second frequency band.