CHARGING PROTECTION CIRCUIT

• US 20150236537A1
• Filed: 05/14/2012
• Published: 08/20/2015
• Est. Priority Date: 03/31/2012
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Luo, Yibao, Guo, Shuai
• Granted Patent: US 9,130,382 B1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02H 7/18 for batteries; for accumulators
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• 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 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Provided is a charging protection circuit. The charging protection circuit includes a wireless charging base and a charging receiving circuit. The charging receiving circuit includes first receiving coils configured to receive electromagnetic waves from the wireless charging base; a high-permeability magnetic core coupled to the first receiving coils and configured to block electromagnetic waves opposite to the electromagnetic waves from the wireless charging base; a detection circuit coupled to the high-permeability magnetic core and configured to detect whether the high-permeability magnetic core has failed; and a power supply circuit coupled to the high-permeability magnetic core and configured to convert electromagnetic energy generated by electromagnetic waves into electric energy to supply power to a power receiving device. With the technical solution, the serious result caused by continuous charging of a wireless charger after a high-permeability magnetic core has failed is avoided, thus guaranteeing the security of a power receiving device.

Claims

1. A charging protection circuit, comprising:

a wireless charging base and a charging receiving circuit, the charging receiving circuit comprising;

first receiving coils which are configured to receive electromagnetic waves from the wireless charging base;

a high-permeability magnetic core which is coupled to the first receiving coils and is configured to block electromagnetic waves opposite to the electromagnetic waves from the wireless charging base;

a detection circuit which is coupled to the high-permeability magnetic core and is configured to detect whether the high-permeability magnetic core has failed; and

a power supply circuit which is coupled to the high-permeability magnetic core and is configured to convert electromagnetic energy generated by the electromagnetic waves into electric energy to supply power to a power receiving device.

2. The charging protection circuit according to claim 1, wherein the detection circuit comprises:

second receiving coils which are configured to receive the electromagnetic waves from the wireless charging base;

a converter which is coupled to the second receiving coils and configured to convert electromagnetic energy generated by the electromagnetic waves received by the second receiving coils into an induction current;

a first detection sensor which is coupled to the converter and configured to detect magnitude of the induction current; and

a second comparator which is coupled to the first detection sensor and configured to compare the detected induction current with a preset induction current threshold and determine that the high-permeability magnetic core has failed when the detected induction current is greater than the preset induction current threshold.

3. The charging protection circuit according to claim 1, wherein the detection circuit comprises:

third receiving coils which are configured to receive the electromagnetic waves from the wireless charging base;

a second detection sensor which is coupled to the third receiving coils and configured to detect a coupling power of the electromagnetic waves received by the third receiving coils; and

a third comparator which is coupled to the second detection sensor and configured to compare the detected coupling power with a preset power threshold and determine that the high-permeability magnetic core has failed when the detected coupling power is greater than the preset power threshold.

4. The charging protection circuit according to claim 1, wherein the charging receiving circuit further comprises:

a first alarm which is configured to give an alarm when the detection circuit detects that the high-permeability magnetic core has failed.

5. The charging protection circuit according to claim 1, wherein the charging receiving circuit further comprises:

a near field communication (NFC) communication circuit which is coupled to the detection circuit and configured to issue an NFC shutdown charging signal when the detection circuit detects that the high-permeability magnetic core has failed.

6. The charging protection circuit according to claim 5, wherein the wireless charging base comprises:

an amplitude wave detection circuit which is configured to detect a signal from the NFC communication circuit;

an NFC demodulation circuit which is coupled to the amplitude wave detection circuit and configured to demodulate the signal detected by the amplitude wave detection circuit; and

a control circuit which is coupled to the NFC demodulation circuit and configured to cut off a power supply switch when a signal obtained by the demodulation is the NFC shutdown charging signal.

7. The charging protection circuit according to claim 6, wherein the wireless charging base further comprises:

a second alarm which is configured to give an alarm when the signal obtained by the demodulation is the NFC shutdown charging signal.

8. The charging protection circuit according to claim 1, wherein a coupling resonant frequency of the detection circuit is a frequency of the electromagnetic waves from the wireless charging base, or a receiving frequency of the detection circuit is high-order harmonics of the frequency of the electromagnetic waves from the wireless charging base.

9. The charging protection circuit according to claim 1, wherein a coupling area of the detection circuit and the high-permeability magnetic core is the same as an area of the high-permeability magnetic core.

10. The charging protection circuit according to claim 1, wherein an LC circuit is provided between the second receiving coils or between the third receiving coils, wherein the LC circuit is configured to fine tune a resonant frequency of the detection circuit.

11. The charging protection circuit according to claim 2, wherein the charging receiving circuit further comprises:

a first alarm which is configured to give an alarm when the detection circuit detects that the high-permeability magnetic core has failed.

12. The charging protection circuit according to claim 3, wherein the charging receiving circuit further comprises:

a first alarm which is configured to give an alarm when the detection circuit detects that the high-permeability magnetic core has failed.

13. The charging protection circuit according to claim 2, wherein the charging receiving circuit further comprises:

a near field communication (NFC) communication circuit which is coupled to the detection circuit and configured to issue an NFC shutdown charging signal when the detection circuit detects that the high-permeability magnetic core has failed.

14. The charging protection circuit according to claim 3, wherein the charging receiving circuit further comprises:

a near field communication (NFC) communication circuit which is coupled to the detection circuit and configured to issue an NFC shutdown charging signal when the detection circuit detects that the high-permeability magnetic core has failed.

15. The charging protection circuit according to claim 13, wherein the wireless charging base comprises:

an amplitude wave detection circuit which is configured to detect a signal from the NFC communication circuit;

an NFC demodulation circuit which is coupled to the amplitude wave detection circuit and configured to demodulate the signal detected by the amplitude wave detection circuit; and

a control circuit which is coupled to the NFC demodulation circuit and configured to cut off a power supply switch when a signal obtained by the demodulation is the NFC shutdown charging signal.

16. The charging protection circuit according to claim 14, wherein the wireless charging base comprises:

an amplitude wave detection circuit which is configured to detect a signal from the NFC communication circuit;

an NFC demodulation circuit which is coupled to the amplitude wave detection circuit and configured to demodulate the signal detected by the amplitude wave detection circuit; and

a control circuit which is coupled to the NFC demodulation circuit and configured to cut off a power supply switch when a signal obtained by the demodulation is the NFC shutdown charging signal.

17. The charging protection circuit according to claim 15, wherein the wireless charging base further comprises:

a second alarm which is configured to give an alarm when the signal obtained by the demodulation is the NFC shutdown charging signal.

18. The charging protection circuit according to claim 16, wherein the wireless charging base further comprises:

a second alarm which is configured to give an alarm when the signal obtained by the demodulation is the NFC shutdown charging signal.

19. The charging protection circuit according to claim 2, wherein a coupling resonant frequency of the detection circuit is a frequency of the electromagnetic waves from the wireless charging base, or a receiving frequency of the detection circuit is high-order harmonics of the frequency of the electromagnetic waves from the wireless charging base.

20. The charging protection circuit according to claim 3, wherein a coupling resonant frequency of the detection circuit is a frequency of the electromagnetic waves from the wireless charging base, or a receiving frequency of the detection circuit is high-order harmonics of the frequency of the electromagnetic waves from the wireless charging base.