Intruding metal detection method for induction type power supply system and related supplying-end module

• US 10,587,153 B2
• Filed: 09/02/2018
• Issued: 03/10/2020
• Est. Priority Date: 02/01/2011
• Status: Active Grant

• Current Assignee: Fu Da Tong Technology Co., Ltd.
• Original Assignee: Fu Da Tong Technology Co., Ltd.
• Inventors: Tsai, Ming-Chiu, Chan, Chi-Che
• Primary Examiner(s): Pham, Ly D
• Application Number:
  US16/120,302
• Publication Number:
  US 20180375386A1
• Time in Patent Office: 555 Days
• Field of Search: 700292, 702189, 702 57, 702 64, 324713
• CPC Class Codes: G01R 33/0283 in which a current or voltage is generated due to relative movement of conductor and magnetic field
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips
• CPC Class Codes: G06F 15/00 Digital computers in general details G06F1/00 – G06F13/00; Data processing equipment in general
• CPC Class Codes: H02J 50/05 using capacitive coupling
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices

Abstract

The present invention discloses an intruding metal detection method for a supplying-end module of an induction type power supply system having a supplying-end coil controlled by a first driving signal and a second driving signal. The method includes periodically generating a detection signal on the first driving signal and the second driving signal, wherein the detection signal controls the supplying-end coil to resonate and generate a coil signal; setting at least one threshold voltage and comparing a plurality of peak values of the coil signal with the at least one threshold voltage, respectively, to generate a plurality of trigger signals; determining whether to perform a pre-charging procedure according to a resonant frequency of the coil signal; and determining whether there is an intruding metal existing in a power supply range of the induction type power supply system according to the plurality of trigger signals and the resonant frequency.

Claims

1. An intruding metal detection method for a supplying-end module of an induction type power supply system, the supplying-end module comprising a supplying-end coil controlled by a first driving signal and a second driving signal, the intruding metal detection method comprising:

periodically generating a detection signal on the first driving signal and the second driving signal, wherein the detection signal controls the supplying-end coil to resonate and generate a coil signal;

setting at least one threshold voltage and comparing a plurality of peak values of the coil signal with the at least one threshold voltage, respectively, to generate a plurality of trigger signals;

determining whether to perform a pre-charging procedure according to a resonant frequency of the coil signal; and

determining whether there is an intruding metal existing in a power supply range of the induction type power supply system according to the plurality of trigger signals and the resonant frequency.

2. The intruding metal detection method of claim 1, wherein in the step of periodically generating the detection signal on the first driving signal and the second driving signal, each time generating the detection signal comprises:

controlling the first driving signal and the second driving signal to be simultaneously switched between a first voltage level and a second voltage level by multiple times; and

when the second driving signal is in the second voltage level after the first driving signal and the second driving signal are controlled to be simultaneously switched by multiple times, controlling only the first driving signal to be switched to the first voltage level and then return to the second voltage level to form a pulse signal, allowing the supplying-end coil to resonate according to the pulse signal.

3. The intruding metal detection method of claim 1, wherein the pre-charging procedure comprises:

sending electric power to charge a capacitor in a receiving-end module of the induction type power supply system, wherein a time length and energy delivery of sending the electric power are insufficient to activate an operation of the receiving-end module responding with a data code.

4. The intruding metal detection method of claim 1, further comprising:

determining whether a receiving-end module of the induction type power supply system is malfunctioned according to the plurality of trigger signals.

5. The intruding metal detection method of claim 1, wherein the step of setting the at least one threshold voltage comprises:

obtaining a reference voltage from the coil signal when the detection signal is generated; and

multiplying the reference voltage by at least one ratio, respectively, to generate the at least one threshold voltage.

6. The intruding metal detection method of claim 1, wherein the at least one threshold voltage comprises a plurality of threshold voltages, and the step of setting the at least one threshold voltage comprises:

obtaining a reference voltage from the coil signal when the detection signal is generated; and

multiplying the reference voltage by a first ratio, a second ratio and a third ratio, respectively, to generate a first threshold voltage, a second threshold voltage and a third threshold voltage among the plurality of threshold voltages, respectively.

7. The intruding metal detection method of claim 6, wherein the first ratio is one quarter, the second ratio is one eighth, and the third ratio is one sixteenth.

8. The intruding metal detection method of claim 6, wherein the step of comparing the plurality of peak values of the coil signal with the at least one threshold voltage, respectively, to generate the plurality of trigger signals comprises:

comparing the plurality of peak values with the first threshold voltage to generate at least one first trigger signal among the plurality of trigger signals;

comparing the plurality of peak values with the second threshold voltage to generate at least one second trigger signal among the plurality of trigger signals when the at least one first trigger signal stops emerging, wherein the second threshold voltage is smaller than the first threshold voltage; and

comparing the plurality of peak values with the third threshold voltage to generate at least one third trigger signal among the plurality of trigger signals when the at least one second trigger signal stops emerging, wherein the third threshold voltage is smaller than the second threshold voltage.

9. The intruding metal detection method of claim 8, wherein the step of determining whether there is an intruding metal existing in the power supply range of the induction type power supply system according to the plurality of trigger signals comprises:

calculating a time length of emergences of the at least one first trigger signal, the at least one second trigger signal and the at least one third trigger signal.

10. The intruding metal detection method of claim 9, wherein the steps of determining whether to perform the pre-charging procedure according to the resonant frequency of the coil signal and determining whether there is an intruding metal existing in the power supply range of the induction type power supply system according to the plurality of trigger signals and the resonant frequency comprise:

comparing the time length with a predefined time value;

determining that there is no intruding metal existing in the power supply range of the induction type power supply system when the time length is greater than the predefined time value; and

further performing the following steps when the time length is smaller than the predefined time value;

comparing the resonant frequency with a predefined frequency value;

determining that there is an intruding metal existing in the power supply range of the induction type power supply system when the resonant frequency is greater than the predefined frequency value; and

performing the pre-charging procedure and then comparing the time length with the predefined time value again when the resonant frequency is smaller than the predefined frequency value.

11. The intruding metal detection method of claim 10, further comprising:

determining that there is an intruding metal existing in the power supply range of the induction type power supply system or the induction type power supply system does not operate normally after a number of times the pre-charging procedure is performed reaches a predefined number while the time length is still determined to be smaller than the predefined time value.

12. A supplying-end module for an induction type power supply system, for performing an intruding metal detection method, the supplying-end module comprising:

a supplying-end coil;

a power driver, coupled to the supplying-end coil, for outputting a first driving signal and a second driving signal to the supplying-end coil, and periodically generating a detection signal on the first driving signal and the second driving signal, wherein the detection signal controls the supplying-end coil to resonate and generate a coil signal;

a signal receiver, coupled to the supplying-end coil, for setting at least one threshold voltage and comparing a plurality of peak values of the coil signal with the at least one threshold voltage, respectively, to generate a plurality of trigger signals; and

a processor, coupled to the signal receiver, for performing the following steps;

determining whether to perform a pre-charging procedure according to a resonant frequency of the coil signal; and

determining whether there is an intruding metal existing in a power supply range of the induction type power supply system according to the plurality of trigger signals and the resonant frequency.

13. The supplying-end module of claim 12, wherein the power driver performs the following steps to generate the detection signal:

controlling the first driving signal and the second driving signal to be simultaneously switched between a first voltage level and a second voltage level by multiple times; and

when the second driving signal is in the second voltage level after the first driving signal and the second driving signal are controlled to be simultaneously switched by multiple times, controlling only the first driving signal to be switched to the first voltage level and then return to the second voltage level to form a pulse signal, allowing the supplying-end coil to resonate according to the pulse signal.

14. The supplying-end module of claim 12, wherein the pre-charging procedure comprises:

sending electric power to charge a capacitor in a receiving-end module of the induction type power supply system, wherein a time length and energy delivery of sending the electric power are insufficient to activate an operation of the receiving-end module responding with a data code.

15. The supplying-end module of claim 12, wherein the processor further determines whether a receiving-end module of the induction type power supply system is malfunctioned according to the plurality of trigger signals.

16. The supplying-end module of claim 12, wherein the signal receiver performs the following steps to set the at least one threshold voltage:

obtaining a reference voltage from the coil signal when the detection signal is generated; and

multiplying the reference voltage by at least one ratio, respectively, to generate the at least one threshold voltage.

17. The supplying-end module of claim 12, wherein the at least one threshold voltage comprises a plurality of threshold voltages, and the signal receiver performs the following steps to set the plurality of threshold voltages:

obtaining a reference voltage from the coil signal when the detection signal is generated; and

multiplying the reference voltage by a first ratio, a second ratio and a third ratio, respectively, to generate a first threshold voltage, a second threshold voltage and a third threshold voltage among the plurality of threshold voltages, respectively.

18. The supplying-end module of claim 17, wherein the first ratio is one quarter, the second ratio is one eighth, and the third ratio is one sixteenth.

19. The supplying-end module of claim 17, wherein the signal receiver performs the following steps to compare the plurality of peak values of the coil signal with the at least one threshold voltage, respectively, to generate the plurality of trigger signals:

comparing the plurality of peak values with the first threshold voltage to generate at least one first trigger signal among the plurality of trigger signals;

comparing the plurality of peak values with the second threshold voltage to generate at least one second trigger signal among the plurality of trigger signals when the at least one first trigger signal stops emerging, wherein the second threshold voltage is smaller than the first threshold voltage; and

comparing the plurality of peak values with the third threshold voltage to generate at least one third trigger signal among the plurality of trigger signals when the at least one second trigger signal stops emerging, wherein the third threshold voltage is smaller than the second threshold voltage.

20. The supplying-end module of claim 19, wherein the processor performs the following steps to determine whether there is an intruding metal existing in the power supply range of the induction type power supply system according to the plurality of trigger signals:

calculating a time length of emergences of the at least one first trigger signal, the at least one second trigger signal and the at least one third trigger signal.

21. The supplying-end module of claim 20, wherein the processor performs the following steps to determine whether to perform the pre-charging procedure according to the resonant frequency of the coil signal and determine whether there is an intruding metal existing in the power supply range of the induction type power supply system according to the plurality of trigger signals and the resonant frequency:

comparing the time length with a predefined time value;

determining that there is no intruding metal existing in the power supply range of the induction type power supply system when the time length is greater than the predefined time value; and

further performing the following steps when the time length is smaller than the predefined time value;

comparing the resonant frequency with a predefined frequency value;

determining that there is an intruding metal existing in the power supply range of the induction type power supply system when the resonant frequency is greater than the predefined frequency value; and

performing the pre-charging procedure and then comparing the time length with the predefined time value again when the resonant frequency is smaller than the predefined frequency value.

22. The supplying-end module of claim 21, wherein the processor determines that there is an intruding metal existing in the power supply range of the induction type power supply system or the induction type power supply system does not operate normally after a number of times the pre-charging procedure is performed reaches a predefined number while the time length is still determined to be smaller than the predefined time value.