Power supply device of induction type power supply system and RF magnetic card identification method of the same

• US 10,630,113 B2
• Filed: 09/16/2018
• Issued: 04/21/2020
• 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): Elamin, Abdelmoniem I
• Application Number:
  US16/132,464
• Publication Number:
  US 20190027971A1
• Time in Patent Office: 583 Days
• CPC Class Codes: G05F 1/66 Regulating electric power
• 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: H02J 50/05 using capacitive coupling
• CPC Class Codes: H02J 50/12 of the resonant type

Abstract

A power supply device used in an induction type power supply system is provided that includes a power supply coil, an auxiliary coil, a power supply driving module, a auxiliary driving module, a harmonic frequency measuring module, a voltage measuring module and a processing module. The power supply driving module drives the power supply coil. The auxiliary driving module drives the auxiliary coil. The harmonic frequency measuring module measures a resonance frequency of the power-supply coil according to a capacitive and inductive parameter related to the power-supply coil. The voltage measuring module tracks and locks a maximum of an oscillation voltage of the auxiliary coil. When the processing module determines that the resonance frequency is stable and the oscillation voltage decreases more than a predetermined ratio of the oscillation voltage, the processing module keeps the power supply driving module under a non-working status.

Claims

1. A power supply device used in an induction type power supply system, wherein the power supply device comprises:

a power supply coil;

an auxiliary coil;

a power supply driving module electrically coupled to the power supply coil and configured to drive the power supply coil;

an auxiliary driving module electrically coupled to the auxiliary coil and configured to drive the auxiliary coil when the power supply driving module is under a non-working status;

a resonant frequency measuring module electrically coupled to the power supply coil and configured to measure a resonant frequency of the power supply coil according to a capacitive and inductive parameter related to the power supply coil;

a voltage measuring module electrically coupled to the auxiliary coil and configured to track and lock a maximum of an oscillating voltage of the auxiliary coil; and

a processing module configured to keep the power supply driving module under the non-working status when the resonant frequency is determined to be stable and the oscillating voltage is determined to be decreased more than a predetermined ratio.

2. The power supply device of claim 1, wherein the processing module further determines that a RF magnetic card exists within a power supplying range of the power supply coil when the resonant frequency is determined to be stable and the oscillating voltage is determined to be decreased more than a predetermined ratio.

3. The power supply device of claim 1, wherein the voltage measuring module comprises:

a digital to analog converter configured to generate a reference voltage; and

a comparator electrically coupled to the digital to analog converter and the auxiliary coil and configured to receive the reference voltage and the oscillating voltage to track and lock the oscillating voltage.

4. The power supply device of claim 3, wherein the comparator is configured to control the digital to analog converter to use the reference voltage to track and lock the oscillating voltage by using a feedback mechanism according to a comparison result of the oscillating voltage and the reference voltage.

5. The power supply device of claim 4, further comprising a voltage-dividing module electrically coupled between the auxiliary coil and the comparator, and the oscillating voltage received by the comparator is a divided voltage of a voltage on the auxiliary coil.

6. The power supply device of claim 1, wherein when the resonant frequency is determined to be unstable and the oscillating voltage is determined to be not decreased more than a predetermined ratio, the processing module keeps the power supply driving module under a working status to drive the power supply coil to transmit a power signal.

7. The power supply device of claim 1, wherein the processing module determines whether the resonant frequency equals to a frequency locked value and determines that the resonant frequency is stable when the resonant frequency equals to the frequency locked value;

the processing module further determines that the resonant frequency is unstable when the resonant frequency does not equal to the frequency locked value to further assign the newly measured resonant frequency as the frequency locked value.

8. The power supply device of claim 1, wherein the processing module determines whether the oscillating voltage is larger than a voltage locked value to retrieve a value that is the predetermined ratio of the voltage locked value as a threshold value when the oscillating voltage is not larger than a voltage locked value, the processing module further determines that the oscillating voltage decreases more than the predetermined ratio when the oscillating voltage is smaller than the threshold value and determines that the oscillating voltage does not decrease more than the predetermined ratio when the oscillating voltage is not smaller than the threshold value;

the processing module further determines that the oscillating voltage does not decrease more than the predetermined ratio when the oscillating voltage is larger than the voltage locked value to further assign the newly measured oscillating voltage as the voltage locked value.

9. A RF magnetic card identifying method used in a power supply device in an induction type power supply system, wherein the RF magnetic card identifying method comprises:

driving a power supply coil of the power supply device by a power supply driving module electrically coupled to the power supply coil;

measuring a resonant frequency of the power supply coil according to a capacitive and inductive parameter related to the power supply coil by a resonant frequency measuring module electrically coupled to the power supply coil;

driving an auxiliary coil of the power supply device by an auxiliary driving module electrically coupled to the auxiliary coil when the power supply driving module is under a non-working status;

tracking and locking a maximum of an oscillating voltage of the auxiliary coil by a voltage measuring module electrically coupled to the auxiliary coil; and

keeping the power supply driving module under a non-working status by a processing module when the resonant frequency is determined to be stable and the oscillating voltage is determined to be decreased more than a predetermined ratio.

10. The RF magnetic card identifying method of claim 9, further comprising:

determining that a RF magnetic card exists within a power supplying range of the power supply coil when the resonant frequency is determined to be stable and the oscillating voltage is determined to be decreased more than a predetermined ratio.

11. The RF magnetic card identifying method of claim 9, further comprising:

generating a reference voltage by a digital to analog converter of the voltage measuring module; and

receiving the reference voltage and a detected voltage related to the auxiliary coil to track and lock the oscillating voltage by a comparator of the voltage measuring module.

12. The RF magnetic card identifying method of claim 11, further comprising:

controlling the digital to analog converter to use the reference voltage to track and lock the oscillating voltage by using a feedback mechanism according to a comparison result of the oscillating voltage and the reference voltage by the comparator.

13. The RF magnetic card identifying method of claim 12, further comprising:

receiving a divided voltage of a voltage on the auxiliary coil as the oscillating voltage by the comparator.

14. The RF magnetic card identifying method of claim 9, further comprising:

keeping the power supply driving module under a working status by the processing module to drive the power supply coil to transmit a power signal when the resonant frequency is determined to be unstable and the oscillating voltage is determined to be not decreased more than a predetermined ratio.

15. The RF magnetic card identifying method of claim 9, further comprising:

determining whether the resonant frequency equals to a frequency locked value and determining that the resonant frequency is stable when the resonant frequency equals to the frequency locked value by the processing module; and

determining that the resonant frequency is unstable when the resonant frequency does not equal to the frequency locked value to further assign the newly measured resonant frequency as the frequency locked value by the processing module.

16. The RF magnetic card identifying method of claim 9, further comprising:

determining whether the oscillating voltage is larger than a voltage locked value to retrieve a value that is the predetermined ratio of the voltage locked value as a threshold value when the oscillating voltage is not larger than a voltage locked value, and further determining that the oscillating voltage decreases more than the predetermined ratio when the oscillating voltage is smaller than the threshold value and determining that the oscillating voltage does not decrease more than the predetermined ratio when the oscillating voltage is not smaller than the threshold value by the processing module; and

determining that the oscillating voltage does not decrease more than the predetermined ratio when the oscillating voltage is larger than the voltage locked value to further assign the newly measured oscillating voltage as the voltage locked value by the processing module.