IP Library Granted Patent US 12,580,425
Granted Patent B2
US 12,580,425 · App. 18/094,066 · Granted Mar 17, 2026

Method for detecting foreign object and electronic device

Inventors: Hyungkoo Chung (Suwon-si, KR); Dongzo Kim (Suwon-si, KR); Mincheol Ha (Suwon-si, KR); Yusu Kim (Suwon-si, KR); Kihyun Kim (Suwon-si, KR); Yunjeong Noh (Suwon-si, KR); Keyic Son (Suwon-si, KR); Taehyeon Yu (Suwon-si, KR); Kyungmin Lee (Suwon-si, KR)
Assignee: SAMSUNG ELECTRONICS CO., LTD.
H02J50/60H02J50/12H02J50/80
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,580,425
App. No.
18/094,066
Granted
Mar 17, 2026
Kind
B2
Abstract

An electronic device capable of transmitting and receiving wireless power may include a wireless power transfer (WPT) coil and a processor configured to be operatively connected to the WPT coil, wherein the processor may perform control to transmit a first ping signal to an external object through the WPT coil, may identify a waveform of a current or voltage measured while or after transmitting the first ping signal, may obtain a Q factor, based on the identified waveform, may control a power transmission operation by determining that the external object is a foreign object or includes the foreign object and is positioned on a center of the WPT coil when the obtained Q factor is less than a predetermined Q factor, may transmit a second ping signal to the external object through the WPT coil when the obtained Q factor is equal to or greater than the predetermined Q factor, may identify a waveform of a current or voltage while or after transmitting the second ping signal, may identify inductance measured at both ends of the WPT coil, based on the identified waveform, and may control the power transmission operation by determining that the external object is the foreign object or includes the foreign object and is positioned in a surrounding area of the WPT coil, based on the measured inductance.

Claims (67)

1 . An electronic device capable of transmitting and receiving wireless power, the electronic device comprising:

a wireless power transfer (WPT) coil; and

a processor configured to be operatively connected to the WPT coil,

wherein the processor is configured to:

perform control to transmit a first ping signal to an external object through the WPT coil;

identify a waveform of a current or voltage measured while or after transmitting the first ping signal;

obtain a Q factor, based on the identified waveform;

control a power transmission operation by determining that the external object is a foreign object or comprises the foreign object and is positioned on a center of the WPT coil based on the obtained Q factor being less than a predetermined Q factor;

transmit a second ping signal to the external object through the WPT coil based on the obtained Q factor being equal to or greater than the predetermined Q factor;

identify a waveform of a current or voltage while or after transmitting the second ping signal;

identify inductance measured at both ends of the WPT coil, based on the identified waveform; and

control the power transmission operation by determining that the external object is the foreign object or comprises the foreign object and is positioned in a surrounding area of the WPT coil, based on the measured inductance.

2 . The electronic device of claim 1 , wherein the processor is configured to perform control to maintain the power transmission operation by determining that the external object is not the foreign object or does not comprise the foreign object based on the measured inductance being equal to or greater than a predetermined inductance.

3 . The electronic device of claim 1 , wherein the second ping signal has a higher frequency than the first ping signal.

4 . The electronic device of claim 1 , wherein the processor is configured to:

estimate that the external object is positioned in the surrounding area of the WPT coil based on the obtained Q factor being equal to or greater than the predetermined Q factor;

measure first inductance measured at both ends of the WPT coil, based on the second ping signal; and

control the power transmission operation by determining that the external object comprises the foreign object or is the foreign object and is positioned in the surrounding area the WPT coil based on the measured first inductance being less than a first predetermined inductance.

5 . The electronic device of claim 1 , wherein the processor is configured to control the power transmission operation by determining that the external object comprises the foreign object or is the foreign object and is positioned on the center of the WPT coil based on the obtained Q factor being less than the predetermined Q factor.

6 . The electronic device of claim 1 , wherein the processor is configured to:

perform a ping operation based on determining that power loss is equal to or greater than a predetermined value during the power transmission operation with an external electronic device;

maintain display of a user interface relating to charging while performing the ping operation; and

control a fast charging operation to a normal charging operation based on the power transmission operation being the fast charging operation.

7 . An electronic device capable of transmitting and receiving wireless power, the electronic device comprising:

a wireless power transfer (WPT) coil; and

a processor configured to be operatively connected to the WPT coil,

wherein the processor is configured to:

transmit a first ping signal to an external object through the WPT coil;

identify a waveform of a current or voltage while or after transmitting the first ping signal,

obtain a Q factor, based on the identified waveform;

measure inductance at both ends of the WPT coil, based on the identified waveform; and

control a power transmission operation by determining that the external object is a foreign object or comprises the foreign object and is positioned in a surrounding area of the WPT coil based on the obtained Q factor being equal to or greater than a predetermined Q factor and the measured inductance being less than a predetermined inductance.

8 . The electronic device of claim 7 , wherein the processor is configured to control the power transmission operation by determining that the external object is not the foreign object or does not comprise the foreign object and is positioned in the surrounding area of the WPT coil based on the obtained Q factor being equal to or greater than the predetermined Q factor and the measured inductance being equal to or greater than the predetermined inductance.

9 . The electronic device of claim 7 , wherein the processor is configured to control the power transmission operation by determining that the external object is the foreign object or comprises the foreign object and is positioned on a center of the WPT coil based on the obtained Q factor being less than the predetermined Q factor.

10 . The electronic device of claim 7 , wherein the processor is configured to control the power transmission operation by determining that the external object is the foreign object or comprises the foreign object and is positioned in the surrounding area of the WPT coil based on the measured inductance being less than the predetermined inductance.

11 . A foreign object detection method of an electronic device capable of transmitting and receiving wireless power using a wireless power transfer (WPT) coil, the method comprising:

transmitting a first ping signal to an external object through the WPT coil;

identifying a waveform of a current or voltage measured while or after transmitting the first ping signal;

obtaining a Q factor, based on the identified waveform;

controlling a power transmission operation by determining that the external object is a foreign object or comprises the foreign object and is positioned on a center of the WPT coil based on the obtained Q factor being less than a predetermined Q factor;

transmitting a second ping signal to the external object through the WPT coil based on the obtained Q factor being equal to or greater than the predetermined Q factor;

identifying a waveform of a current or voltage while or after transmitting the second ping signal;

identifying inductance measured at both ends of the WPT coil, based on the identified waveform; and

controlling the power transmission operation by determining that the external object is the foreign object or comprises the foreign object and is positioned in a surrounding area of the WPT coil, based on the measured inductance.

12 . The method of claim 11 , further comprising performing control to maintain the power transmission operation by determining that the external object is not the foreign object or does not comprise the foreign object based on the measured inductance being equal to or greater than a predetermined inductance.

13 . The method of claim 11 , wherein the second ping signal has a higher frequency than the first ping signal.

14 . The method of claim 11 , further comprising:

determining that the external object is positioned in the surrounding area of the WPT coil based on the obtained Q factor being equal to or greater than the predetermined Q factor;

measuring first inductance measured at both ends of the WPT coil, based on the second ping signal; and

controlling the power transmission operation by determining that the external object comprises the foreign object or is the foreign object and is positioned in the surrounding area the WPT coil based on the measured first inductance being less than a first predetermined inductance.

15 . The method of claim 11 , further comprising:

determining that the external object is positioned on the center of the WPT coil based on the obtained Q factor being less than the predetermined Q factor;

measuring second inductance measured at both ends of the WPT coil, based on the first ping signal; and

controlling the power transmission operation by determining that the external object comprises the foreign object or is the foreign object and is positioned on the center of the WPT coil based on the measured second inductance being less than a second predetermined inductance.

16 . The method of claim 11 , further comprising:

performing a ping operation based on determining that power loss is equal to or greater than a predetermined value during the power transmission operation with an external electronic device;

maintaining display of a user interface relating to charging while performing the ping operation; and

controlling a fast charging operation to a normal charging operation based on the power transmission operation being the fast charging operation.

17 . A foreign object detection method of an electronic device capable of transmitting and receiving wireless power using a wireless power transfer (WPT) coil, the method comprising:

transmitting a first ping signal to an external object through the WPT coil;

identifying a waveform of a current or voltage while or after transmitting the first ping signal;

obtaining a Q factor, based on the identified waveform;

measuring inductance at both ends of the WPT coil, based on the identified waveform; and

controlling a power transmission operation by determining that the external object is a foreign object or comprises the foreign object and is positioned in a surrounding area of the WPT coil based on the obtained Q factor being equal to or greater than a predetermined Q factor and the measured inductance being less than a predetermined inductance.

18 . The method of claim 17 , further comprising controlling the power transmission operation by determining that the external object is not the foreign object or does not comprise the foreign object and is positioned in the surrounding area of the WPT coil in case that the obtained Q factor is equal to or greater than the predetermined Q factor and the measured inductance is equal to or greater than the predetermined inductance.

19 . The method of claim 17 , further comprising controlling the power transmission operation by determining that the external object is the foreign object or comprises the foreign object and is positioned on a center of the WPT coil based on the obtained Q factor being less than the predetermined Q factor.

20 . The method of claim 19 , further comprising controlling the power transmission operation by determining that the external object is the foreign object or comprises the foreign object and is positioned in the surrounding area of the WPT coil based on the obtained Q factor being less than the predetermined Q factor and the measured inductance being less than the predetermined inductance.

Assignments (2)
CORRECTIVE ASSIGNMENT TO CORRECT THE ASSIGNORS PREVIOUSLY RECORDED AT REEL: 062298 FRAME: 0486. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT. Recorded Jan 12, 2023
From: CHUNG, HYUNGKOO; KIM, DONGZO; HA, MINCHEOL; KIM, YUSU; KIM, KIHYUN; NOH, YUNJEONG; SON, KEYIC; YU, TAEHYEON; LEE, KYUNGMIN
To: SAMSUNG ELECTRONICS CO., LTD.
Reel/Frame 062358/0152 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 6, 2023
From: CHUNG, HYUNGKOO; KIM, DONGZO; HA, MINCHEOL; KIM, YUSU; KIM, KIHYUN; NOH, YUNJEONG; SON, KEYIC
To: SAMSUNG ELECTRONICS CO., LTD.
Reel/Frame 062298/0486 →
Priority Claims (2)
KR 10-2021-0173461 · Dec 7, 2021 · national
KR 10-2022-0031285 · Mar 14, 2022 · national
Continuity (2)
Continuation PCTKR2022019668 · Dec 6, 2022
Related Publication 20230179028A1 · Jun 8, 2023
References Cited (33)
US 9553485B2 · Singh et al. · 2017 [cited by applicant]
US 10439445B2 · Jung et al. · 2019 [cited by applicant]
US 11309742B2 · Lee et al. · 2022 [cited by applicant]
US 11418067B2 · Mehas et al. · 2022 [cited by applicant]
US 11539249B2 · Park · 2022 [cited by applicant]
US 20150285926A1 · Oettinger · 2015 [cited by applicant]
US 20160204964A1 · Takahashi et al. · 2016 [cited by applicant]
US 20190052126A1 · Lee et al. · 2019 [cited by applicant]
US 20190312468A1 · Kwon et al. · 2019 [cited by applicant]
US 20200119595A1 · Nakano · 2020 [cited by examiner]
US 20200204005A1 · Lee et al. · 2020 [cited by applicant]
US 20200343765A1 · Kwon et al. · 2020 [cited by applicant]
US 20210167637A1 · Schwartz et al. · 2021 [cited by applicant]
US 20220123598A1 · Wu · 2022 [cited by examiner]
EP 4228123 · 2023 [cited by applicant]
JP 2015154159 · 2015 [cited by applicant]
JP 6387222 · 2018 [cited by applicant]
KR 1020170140685 · 2017 [cited by applicant]
KR 101812444 · 2017 [cited by applicant]
KR 1020180038205 · 2018 [cited by applicant]
KR 1020180065693 · 2018 [cited by applicant]
KR 101955806 · 2019 [cited by applicant]
KR 1020190050301 · 2019 [cited by applicant]
KR 1020200057913 · 2020 [cited by applicant]
KR 1020210000334 · 2021 [cited by applicant]
KR 1020210014712 · 2021 [cited by applicant]
KR 1020210089529 · 2021 [cited by applicant]
KR 1020210092404 · 2021 [cited by applicant]
KR 1020210136954 · 2021 [cited by applicant]
KR 102479879 · 2022 [cited by applicant]
KR 1020230084170 · 2023 [cited by applicant]
Search Report dated Mar. 13, 2023 in International Patent Application No. PCT/KR2022/019668. [cited by applicant]
Written Opinion dated Mar. 13, 2023 in International Patent Application No. PCT/KR2022/019668. [cited by applicant]