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

• US 10,594,168 B2
• Filed: 08/22/2019
• Issued: 03/17/2020
• 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:
  US16/547,588
• Publication Number:
  US 20190379244A1
• Time in Patent Office: 208 Days
• Field of Search: 700292
• 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: G01V 3/10 using induction coils
• CPC Class Codes: G01V 3/105 forming directly coupled primary and secondary coils or loops
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings

Abstract

An intruding metal detection method for a supplying-end module of an induction type power supply system having a supplying-end coil includes: obtaining a previous peak trigger voltage measured during a previous measurement period and setting a reference voltage to be equal to the previous peak trigger voltage; interrupting at least one driving signal of the induction type power supply system to stop driving the supplying-end coil during a measurement period, to generate a coil signal of the supplying-end coil; measuring a first peak of the coil signal within an oscillation cycle of the coil signal, to obtain a first peak trigger voltage; comparing the first peak trigger voltage with the reference voltage; and determining that there is no intruding metal existing in a power supply range of the induction type power supply system when the first peak trigger voltage is equal to or close to the reference voltage.

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, the intruding metal detection method comprising:

obtaining a previous peak trigger voltage measured during a previous measurement period and setting a reference voltage to be equal to the previous peak trigger voltage;

interrupting at least one driving signal of the induction type power supply system to stop driving the supplying-end coil during a measurement period, to generate a coil signal of the supplying-end coil;

measuring a first peak of the coil signal within an oscillation cycle of the coil signal, to obtain a first peak trigger voltage;

comparing the first peak trigger voltage with the reference voltage; and

determining that there is no intruding metal existing in a power supply range of the induction type power supply system when the first peak trigger voltage is equal to or close to the reference voltage.

2. The intruding metal detection method of claim 1, wherein when the first peak trigger voltage is not equal to or close to the reference voltage, the intruding metal detection method further comprises the following steps:

measuring a second peak of the coil signal within a next oscillation cycle of the coil signal to obtain a second peak trigger voltage;

calculating an attenuation parameter according to the first peak trigger voltage and the second peak trigger voltage; and

comparing the attenuation parameter with a threshold value to determine whether there is an intruding metal existing in the power supply range of the induction type power supply system.

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

setting the reference voltage to be equal to the first peak trigger voltage when the first peak trigger voltage is equal to or close to the reference voltage.

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

calculating a consecutive number of times or a duration period where the first peak trigger voltage is determined to be equal to or close to the reference voltage; and

performing the following steps when the consecutive number of times or the duration period reaches an upper limit;

measuring a second peak of the coil signal within a next oscillation cycle of the coil signal to obtain a second peak trigger voltage;

calculating an attenuation parameter according to the first peak trigger voltage and the second peak trigger voltage;

comparing the attenuation parameter with a threshold value to determine whether there is an intruding metal existing in the power supply range of the induction type power supply system; and

resetting a counter to recalculate the consecutive number of times, or resetting a timer to recalculate the duration period.

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

setting a timer, and performing the following steps when the timer expires;

measuring a second peak of the coil signal within a next oscillation cycle of the coil signal to obtain a second peak trigger voltage;

calculating an attenuation parameter according to the first peak trigger voltage and the second peak trigger voltage; and

comparing the attenuation parameter with a threshold value to determine whether there is an intruding metal existing in the power supply range of the induction type power supply system.