Foreign object detection device, method, wireless charging system and electronic equipment

Abstract

The present disclosure provides a foreign object detection device, method, wireless charging system and electronic device. Among them, the foreign object detection device is applied to the wireless charging system, and specifically includes: a sweep frequency signal generator, which is used to generate a sweep frequency signal; a detection module, including a capacitor composed of an inductor coil and a metal frame, the metal frame is arranged around the periphery of the inductor coil, and the inductor coil is connected to the sweep frequency signal generator through a first switch; a conversion module, which is connected to the inductor coil through a second switch and to the metal frame through a third switch, and is used to convert the current generated by the detection module into a detection voltage; a controller, which is connected to the conversion module, and is used to perform foreign object detection on the transmitting coil module of the wireless charging system according to the detection voltage. According to the scheme of the present disclosure, real-time monitoring of different types of foreign objects on the wireless charging system can be achieved.

Description

Technical Field

[0001] The present disclosure relates to the field of wireless charging technology, and in particular to a foreign object detection device, method, wireless charging system and electronic equipment. Background Art

[0002] Wireless charging technology, also known as wireless energy transmission technology, is a technology that transmits electrical energy wirelessly. It does not require the use of traditional power cords and chargers. As long as the power-consuming object (for example, a car, smart home appliance, industrial equipment) is in the charging area, it can automatically obtain charging energy. Summary of the invention

[0003] The present disclosure provides a foreign object detection device, method, wireless charging system and electronic device to solve or alleviate one or more technical problems in the prior art.

[0004] In one aspect, the present disclosure provides a foreign object detection device, which is applied to a wireless charging system, comprising:

[0005] A sweep frequency signal generator, used for generating a sweep frequency signal;

[0006] The detection module includes an inductor coil and a metal frame, wherein the metal frame is arranged around the periphery of the inductor coil and is not closed along the periphery of the inductor coil to form a gap, and the inductor coil is connected to the sweep signal generator through a first switch;

[0007] a conversion module, connected to the inductor coil via the second switch and connected to the metal frame via the third switch, and used for converting the current generated by the detection module into a detection voltage; and

[0008] A controller, connected to the conversion module, for performing foreign object detection on the transmitting coil module of the wireless charging system according to the detection voltage;

[0009] Among them, in the first detection mode, the first switch and the second switch are closed, and the third switch is opened, so as to perform foreign object detection of the first category of foreign objects; in the second detection mode, the first switch and the third switch are closed, and the second switch is opened, so as to perform foreign object detection of the second category of foreign objects.

[0010] On the other hand, the present disclosure provides a foreign body detection method, which is applied to a foreign body detection device of any embodiment of the present disclosure, comprising:

[0011] Determine a detection mode according to the detection instruction, wherein the detection mode includes a first detection mode and / or a second detection mode;

[0012] According to the detection mode, adjusting the opening and closing states of the first switch, the second switch and the third switch;

[0013] Controlling the sweep frequency generator to generate a sweep frequency signal;

[0014] Based on the current generated by the detection module according to the frequency sweep signal, the control conversion module converts the current into a detection voltage;

[0015] The controller is used to compare the first information in the detection voltage with the threshold information to detect the position and range of the foreign matter on the transmitting coil module of the wireless charging system.

[0016] In another aspect, the present disclosure provides a wireless charging system, comprising:

[0017] A transmitting coil module is used to transmit electrical energy to a receiving coil module of an electrical object;

[0018] The foreign object detection device of any embodiment of the present disclosure is connected to the transmitting coil module, wherein the detection module of the foreign object detection device corresponds to the coil setting position in the transmitting coil module.

[0019] In another aspect, the present disclosure provides an electronic device, comprising:

[0020] At least one processor. And

[0021] A memory in communication with the at least one processor.

[0022] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method of any embodiment of the present disclosure.

[0023] On the other hand, the present disclosure provides a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to cause the computer to execute the method according to any embodiment of the present disclosure.

[0024] On the other hand, the present disclosure provides a computer program product, including a computer program, which implements the method according to any embodiment of the present disclosure when executed by a processor.

[0025] According to the solution of the present disclosure, real-time monitoring of different types of foreign objects on a wireless charging system can be achieved.

[0026] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments provided according to the present disclosure and should not be regarded as limiting the scope of the present disclosure.

[0028] Figure 1 is a schematic diagram of a foreign object detection device according to an embodiment of the present disclosure.

[0029] Figure 2 is a schematic diagram of a foreign object detection device according to an embodiment of the present disclosure.

[0030] Figure 3 is a schematic diagram of a detection module according to an embodiment of the present disclosure.

[0031] Figure 4 is a schematic diagram of a detection module according to an embodiment of the present disclosure.

[0032] Figure 5 It is a flow chart of a foreign body detection method according to an embodiment of the present disclosure.

[0033] Figure 6 is a schematic diagram of a wireless charging system according to an embodiment of the present disclosure.

[0034] Figure 7 is a block diagram of an electronic device used to implement the foreign matter detection method of the embodiment of the present disclosure. DETAILED DESCRIPTION

[0035] The present disclosure will be further described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0036] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the main purpose of the present disclosure.

[0037] like Figure 1 , Figure 2 As shown, an embodiment of the present disclosure provides a foreign object detection device 100, which is applied to a wireless charging system and includes: a sweep signal generator 1, a detection module, a conversion module 2 and a controller 3.

[0038] The swept frequency signal generator 1 is used to generate a swept frequency signal.

[0039] The detection module includes a capacitor 4 consisting of an inductor 41 and a metal frame 42. The metal frame 42 is arranged around the periphery of the inductor 41, and the inductor 41 is connected to the sweep signal generator 1 through a first switch 10.

[0040] The conversion module 2 is connected to the inductor 41 through the second switch 20 and to the metal frame 42 through the third switch 30 . The conversion module 2 is used to convert the alternating current generated by the detection module into a detection voltage (alternating voltage).

[0041] The controller 3 is connected to the conversion module 2 and is used to perform foreign object detection on the transmitting coil module of the wireless charging system according to the detection voltage.

[0042] In the first detection mode, the first switch 10 and the second switch 20 are closed, and the third switch 30 is opened, so as to detect the first type of foreign objects. In the second detection mode, the first switch 10 and the third switch 30 are closed, and the second switch 20 is opened, so as to detect the second type of foreign objects.

[0043] According to the embodiments of the present disclosure, it should be noted that:

[0044] The swept frequency signal generator 1 can output a sine wave signal of 200KHz (kilohertz) to 2MHz (megahertz).

[0045] The inductor 41 and the metal frame 42 serve as two electrodes of the capacitor 4. The metal frame 42 can be made of a metal material with high electrical conductivity and good corrosion resistance. For example, it can be made of copper, silver, aluminum, gold, nickel, etc. The metal frame 42 is not closed along the outer circumference of the inductor 41 (such as Figures 1 to 4 As shown), there is a gap. The lead wire connecting the metal frame 42 to the third switch 30 can be set at the electrical zero point of the electrode, and the signal voltages of the power transmission working frequency band of the wireless charging system induced at both ends are equal and opposite in phase, and the voltages cancel each other, reducing its influence on the detection circuit.

[0046] The controller 3 compares the first information in the detection voltage with the pre-stored threshold information to determine whether there is a foreign object on the transmitting coil module of the wireless charging system. The first information includes the first complex impedance of the signal, the signal phase of the signal, and the resonant frequency of the signal. The threshold information includes the threshold complex impedance, the threshold signal phase, and the threshold resonant frequency of the signal output by the conversion module 2 when there is no foreign object on the transmitting coil module.

[0047] The transmitting coil module can be understood as a structure for transmitting electric energy to an electric object. In practical applications, it can be understood as a wireless charging panel in a wireless charging system.

[0048] The first detection mode can be understood as an inductive reactance detection mode. In this mode, the frequency sweep signal generator 1 measures the inductive reactance change rate of the inductive coil 41 in the detection module in a specific frequency band by frequency sweeping, thereby obtaining whether the metal foreign matter exists, and the position and range on the charging coil plate (transmitting coil module).

[0049] The second detection mode can be understood as a capacitive reactance detection mode. In this mode, the frequency sweep signal generator 1 measures the rate of change of the distributed capacitance around the inductor 41 and the metal frame 42 by frequency sweeping, thereby obtaining whether there is a foreign body in the living body, and the position and range on the charging coil plate (transmitting coil module).

[0050] The foreign body detection device 100 of the disclosed embodiment can be integrated into the transmitting coil module of the wireless charging system, or can be assembled with the transmitting coil module as an independent device. The wireless charging system can be applied to wireless charging scenarios of automobiles, sweeping robots, AGV (Automated Guided Vehicle) cars, etc., without specific limitation here.

[0051] In the prior art, the energy transmission of the wireless charging system depends on the high-frequency and high-intensity electromagnetic field distributed around the magnetic field coil (transmitting coil module). When a foreign object enters the charging range of the magnetic field coil, eddy currents will be generated inside it. For metal foreign objects with large impedance, eddy currents will cause a large amount of heat loss. Long-term heating is prone to the dangerous situation of burning the wireless charging system or the object using electricity. Therefore, it is necessary to detect metal foreign objects before and during charging to discover safety hazards in time. In addition, the high-frequency and high-intensity electromagnetic field generated by the wireless charging system during operation will heat the water molecules in the cells of the living foreign objects, thereby causing fatal damage to the living foreign objects. The technology of the embodiment of the present disclosure can effectively solve the above problems. Specifically, according to the technology of the embodiment of the present disclosure, since the capacitor 4 is designed to be composed of an inductor coil 41 and a metal frame 42, it is possible to use the inductor coil 41 in the first detection mode to detect whether there is a metal foreign object on the transmitting coil module of the wireless charging system and the position and range of the metal foreign object. Furthermore, the inductor 41 and the metal frame 42 can be used in the second detection mode to detect whether there is a living foreign body on the transmitting coil module of the wireless charging system and the position and range of the living foreign body. The technology of the disclosed embodiment can not only greatly reduce the cost of foreign body detection by sharing a set of detection modules and conversion modules 2, but also realize the time-sharing switching of the inductive reactance detection mode (first detection module) and the capacitive reactance detection mode (second detection mode), thereby realizing the detection of metal foreign bodies and living foreign bodies when the wireless charging system is started and during charging, and improving the detection performance.

[0052] In one embodiment, the conversion module 2 includes a transimpedance amplifier 21, a first resistor 22 and a second resistor 23, the first resistor 22 is connected to both ends of the transimpedance amplifier 21 through a fourth switch 40, and the second resistor 23 is connected to both ends of the transimpedance amplifier 21 through a fifth switch 50.

[0053] The resistance of the second resistor 23 is greater than the resistance of the first resistor 22. In the first detection mode, the fourth switch 40 is closed and the fifth switch 50 is open. In the second detection mode, the fifth switch 50 is closed and the fourth switch 40 is open.

[0054] According to the technology of the embodiment of the present disclosure, since the conversion module 2 is provided with a branch including the first resistor 22 and a branch including the second resistor 23, it is possible to implement resistance switching according to the first detection mode or the second detection mode, so that the conversion module 2 meets the current and voltage conversion requirements under different detection modes.

[0055] In one embodiment, Figure 1 , Figure 2 As shown, the detection module includes at least one capacitor 4 , each capacitor 4 includes a plurality of inductor coil groups 43 , and a metal frame 42 is disposed around the periphery of the plurality of inductor coil groups 43 .

[0056] The second switch 20 includes a plurality of second sub-switches 201, and each inductor group 43 is connected to the conversion module 2 through a second sub-switch 201. Each inductor group 43 in the plurality of inductor groups 43 includes a plurality of inductors 41, and the plurality of inductors 41 are respectively used to detect foreign objects in different areas of the transmitting coil module. The plurality of inductors 41 are arranged in series or in parallel.

[0057] According to the embodiments of the present disclosure, it should be noted that:

[0058] When multiple inductors 41 are connected in series, Figure 1 , Figure 3 As shown, a plurality of inductors 41 are connected in a first connection, and the inductor 41 at the first end is connected to the first switch 10 , and the inductor 41 at the last end is connected to the second sub-switch 201 .

[0059] When multiple inductors 41 are connected in parallel, Figure 2 , Figure 4 As shown, one end of each inductor 41 is connected to the first switch 10 , and the other end of each inductor 41 is connected to the second sub-switch 201 .

[0060] Each inductor coil group 43 in the plurality of inductor coil groups 43 is used to detect foreign objects in a specific area of ​​the transmitting coil module. Each inductor coil 41 in each inductor coil group 43 is used to detect foreign objects in different sub-areas in the specific area. In this way, the entire area of ​​the transmitting coil module can be subdivided into several small detection areas, so that foreign object detection can be performed more accurately to determine the specific location of the foreign object and the size of the foreign object.

[0061] In one embodiment, the multiple inductance coils 41 of each inductance coil group 43 are arranged at intervals, and an inductance coil 41 of another inductance coil group 43 of the multiple inductance coil groups 43 is arranged between two adjacent inductance coils 41 of the multiple inductance coils 41 .

[0062] For example, Figure 3 , Figure 4 As shown, the capacitor 4 includes four inductance coil groups 43, the first inductance coil group 43 includes inductance coils A10, A11, A12, A13, the second inductance coil group 43 includes inductance coils A20, A21, A22, A23, the third inductance coil group 43 includes inductance coils A30, A31, A32, A33, and the fourth inductance coil group 43 includes inductance coils A40, A41, A42, A43. Among them, the inductance coils A10, A11, A12, A13 are arranged at intervals, the inductance coils A20, A21, A22, A23 are arranged at intervals, the inductance coils A30, A31, A32, A33 are arranged at intervals, and the inductance coils A40, A41, A42, A43 are arranged at intervals. An inductor A30 of the third inductor group 43 is arranged between the inductor A10 and A11, an inductor A20 of the second inductor group 43 is arranged between the inductor A10 and A13, an inductor A21 of the second inductor group 43 is arranged between the inductor A11 and A12, and an inductor A33 of the third inductor group 43 is arranged between the inductor A12 and A13. The spacing arrangement of the inductor 41 in the remaining inductor groups 43 is not described here, and reference is made to Figure 3 and Figure 4 The arrangement of the inductor 41 is shown. It should be noted that the inductor 41 and the inductors A10, A11, A12, A13, A20, A21, A22, A23, A30, A31, A32, A33, A40, A41, A42, A43 are the same inductor.

[0063] According to the technology of the embodiment of the present disclosure, by arranging multiple inductance coils 41 in each inductance coil group 43 at intervals, and arranging inductance coils 41 of other inductance coil groups 43 between two adjacent inductance coils 41, the detection blind area problem caused by the mutual coupling cancellation of the edge inductance of the inductance coil 41 can be solved, so that the edge magnetic field of the inductance coil 41 will not cause a detection blind area due to the mutual inductance cancellation of the magnetic field of the adjacent coil. The blind area problem of foreign object detection is solved without increasing the cost.

[0064] In one embodiment, Figure 3 , Figure 4 As shown, the winding directions of two adjacent inductors 41 in the same inductor group 43 are opposite (for example, inductors A10, A11, A12, A13), and / or the winding directions of both ends of each inductor 41 in the multiple inductors 41 are opposite.

[0065] According to the technology of the embodiment of the present disclosure, the influence of the power transmission working frequency band of the wireless charging system on the conversion module 2 can be well offset, so that the energy of the wireless power transmission frequency component induced at both ends of the inductor 41 is close to zero, thereby preventing the conversion module 2 from entering a saturated working state.

[0066] In one embodiment, Figure 1 , Figure 2 As shown, the detection module includes a plurality of capacitors 4, and the plurality of capacitors 4 are used to perform foreign object detection on different areas of the transmitting coil module.

[0067] The first switch 10 includes a plurality of first sub-switches 101 , and each capacitor 4 is connected to the sweep signal generator 1 via a first sub-switch.

[0068] According to the technology of the embodiment of the present disclosure, multiple capacitors 4 can perform foreign object detection on different target areas of the transmitting coil module, and the entire area of ​​the transmitting coil module can be detected through the combination of multiple capacitors 4.

[0069] Each inductor coil group 43 in the plurality of inductor coil groups 43 is used to detect foreign objects in a specific area of ​​the transmitting coil module. Each inductor coil 41 in each inductor coil group 43 is used to detect foreign objects in different sub-areas in the specific area. In this way, the entire area of ​​the transmitting coil module can be subdivided into several small detection areas, so that foreign object detection can be performed more accurately to determine the specific location of the foreign object and the size of the foreign object.

[0070] In one embodiment, a digital-to-analog conversion circuit 7 is provided between the controller 3 and the conversion module 2 for converting the detection voltage into a digital signal.

[0071] In one implementation, the controller 3 may be connected to the sweep signal generator 1, the first switch 10, the second switch 20, the third switch 30, the fourth switch 40, and the fifth switch 50, and is used to control the sweep signal generator 1 to generate a sweep signal, and to control the switch to be closed or opened.

[0072] In one embodiment, the controller 3 may also be connected to an alarm device, and when a foreign object is detected, a light alarm device 61 and / or a sound alarm device 62 may be used to issue a reminder.

[0073] In one embodiment, the controller 3 is also connected to the wireless charging system, and when a foreign object is detected, an alarm message is sent to the wireless charging system so that the wireless charging system can stop supplying power, that is, stop the transmitting coil module from transmitting power wirelessly.

[0074] In an application example, Figure 1 Taking the foreign body detection device as an example, the first detection mode (inductive reactance detection mode) and the second detection mode (capacitive reactance detection mode) are described respectively. It should be noted that, when the detection module includes multiple capacitors 4, the multiple capacitors 4 sequentially execute the first detection mode and the second detection mode, therefore, the description here using one capacitor 4 as an example can be considered to describe the working process of each capacitor 4.

[0075] For the first detection mode, the working process includes:

[0076] Step 10: close the first switch 10 and the second switch 20 connected to the plurality of inductor coil groups 43 of the capacitor 4, and close the fourth switch 40 connected to the first resistor 22 in the conversion module 2;

[0077] Step 11: Control the sweep frequency generator 1 to generate a sweep frequency signal of 200KHz-2MHz, and the sweep frequency signal is loaded to the conversion module 2 through the inductor 41 of one of the inductor coil groups 43 among the multiple inductor coil groups 43;

[0078] Step 12: The conversion module 2 converts the current generated by the first inductor coil group 43 into a detection voltage;

[0079] Step 13: The digital-to-analog conversion circuit 7 converts the detection voltage into a digital signal and transmits it to the controller 3;

[0080] Step 14: the controller 3 obtains first information of the digital signal through a discrete Fourier transform digital signal processing algorithm, wherein the first information includes a first complex impedance of the detection voltage, a signal phase of the detection voltage, and a resonant frequency of the detection voltage.

[0081] Step 15: The controller 3 compares the changes in complex impedance, signal phase and resonant frequency on the first inductor coil group when there is / is not a metal foreign object, and determines whether there is a metal foreign object at the transmitting coil module position corresponding to the first inductor coil group 43.

[0082] Wherein, when the capacitor 4 includes multiple inductor coil groups 43, each inductor coil group 43 performs steps 11 to 15 respectively. Since the position of the transmitting coil module corresponding to each inductor coil group 43 is different, multiple inductor coil groups 43 perform steps 11 to 15 respectively, so as to accurately detect whether there is a metal foreign body and the size of the metal foreign body at the transmitting coil module position corresponding to the capacitor 4. Similarly, when the detection module includes multiple capacitors 4, multiple capacitors 4 perform steps 10 to 15 respectively, so as to perform metal foreign body detection on all position areas of the transmitting coil module.

[0083] For the second detection mode, the working process includes:

[0084] Step 20: close the first switch 10 connected to the plurality of inductor coil groups 43 of the capacitor 4, close the third switch 30 connected to the metal frame 42, and close the fifth switch 50 in the conversion module 2 connected to the second resistor 23;

[0085] Step 21: Control the sweep frequency generator 1 to generate a sweep frequency signal of 200KHz~2MHz, and the sweep frequency signal is loaded into the conversion module 2 through the inductor 41 of one of the inductor coil groups 43 and the metal frame 42;

[0086] Step 22: The conversion module 2 converts the current generated by the inductor 41 and the metal frame 42 of an inductor group 43 into a detection voltage;

[0087] Step 23: The digital-to-analog conversion circuit 7 converts the detection voltage into a digital signal and transmits it to the controller 3;

[0088] Step 24: the controller 3 obtains first information of the digital signal through a discrete Fourier transform digital signal processing algorithm, wherein the first information includes a first complex impedance of the detection voltage, a signal phase of the detection voltage, and a resonant frequency of the detection voltage.

[0089] Step 25: the controller 3 compares the changes in complex impedance, signal phase and resonant frequency on the first inductor coil group 43 when there is / is not a living foreign body, and determines whether there is a living foreign body at the transmitting coil module position corresponding to the first inductor coil group 43.

[0090] Wherein, when the capacitor 4 includes multiple inductance coil groups 43, each inductance coil group 43 performs steps 21 to 25 respectively. Since the position of the transmitting coil module corresponding to each inductance coil group 43 is different, multiple inductance coil groups 43 perform steps 21 to 25 respectively, so as to accurately detect whether there is a living foreign body and the size of the living foreign body at the transmitting coil module position corresponding to the capacitor 4. Similarly, when the detection module includes multiple capacitors 4, multiple capacitors 4 perform steps 20 to 25 respectively, so as to perform living foreign body detection on all position areas of the transmitting coil module.

[0091] like Figure 5 As shown, an embodiment of the present disclosure provides a foreign body detection method, which is applied to a foreign body detection device of any embodiment of the present disclosure, comprising:

[0092] Step S501: Determine a detection mode according to a detection instruction, wherein the detection mode includes a first detection mode and / or a second detection mode.

[0093] Step S502: adjusting the on / off states of the first switch, the second switch and the third switch according to the detection mode.

[0094] Step S503: controlling the sweep frequency generator to generate a sweep frequency signal.

[0095] Step S504: Based on the current generated by the detection module according to the frequency sweep signal, the conversion module is controlled to convert the current into a detection voltage.

[0096] Step S505: using the controller to compare the first information in the detection voltage with the threshold information to detect the position and range of the foreign object on the transmitting coil module of the wireless charging system.

[0097] According to the embodiments of the present disclosure, it should be noted that:

[0098] The foreign object detection method of the embodiment of the present disclosure may be used when the wireless charging system is started and / or during the charging process.

[0099] The first detection mode and the second detection mode can be performed alternately, thereby achieving all-round detection of metal foreign bodies and living foreign bodies.

[0100] The first information includes a first complex impedance of the detection voltage, a signal phase of the detection voltage, and a resonant frequency of the detection voltage.

[0101] The threshold information includes a threshold complex impedance, a threshold signal phase, and a threshold resonant frequency of a signal output by the conversion module when there is no foreign matter on the transmitting coil module.

[0102] In the prior art, the energy transmission of the wireless charging system depends on the high-frequency and high-intensity electromagnetic field distributed around the magnetic field coil (transmitting coil module). When a foreign object enters the charging range of the magnetic field coil, eddy currents will be generated inside it. For metal foreign objects with large impedance, eddy currents will cause a large amount of heat loss. Long-term heating is prone to the dangerous situation of burning the wireless charging system or the object using electricity. Therefore, it is necessary to detect metal foreign objects before and during charging to discover safety hazards in time. In addition, the high-frequency and high-intensity electromagnetic field generated by the wireless charging system during operation will heat the water molecules in the cells of the living foreign objects, thereby causing fatal damage to the living foreign objects. The technology of the embodiment of the present disclosure can effectively solve the above problems. Specifically, according to the technology of the embodiment of the present disclosure, it can be realized in the first detection mode to use the inductor coil to detect whether there is a metal foreign object on the transmitting coil module of the wireless charging system and the position and range of the metal foreign object. And it can be realized in the second detection mode to use the inductor coil and the metal frame to detect whether there is a living foreign object on the transmitting coil module of the wireless charging system and the position and range of the living foreign object.

[0103] In one embodiment, step S504: based on the current generated by the detection module according to the frequency sweep signal, controlling the conversion module to convert the current into a detection voltage includes:

[0104] According to the detection mode, the opening and closing states of the fourth switch and the fifth switch are adjusted to determine the conversion mode of the conversion module.

[0105] According to the conversion mode, based on the current generated by the detection module according to the sweep signal, the conversion module is controlled to convert the current into a detection voltage.

[0106] In an application example, Figure 1 Taking the foreign body detection device as an example, the first detection mode (inductive reactance detection mode) and the second detection mode (capacitive reactance detection mode) are described respectively. It should be noted that, when the detection module includes multiple capacitors 4, the multiple capacitors 4 sequentially execute the first detection mode and the second detection mode, therefore, the description here using one capacitor 4 as an example can be considered to describe the working process of each capacitor 4.

[0107] For the first detection mode, the working process includes:

[0108] Step 10: close the first switch 10 and the second switch 20 connected to the plurality of inductor coil groups 43 of the capacitor 4, and close the fourth switch 40 connected to the first resistor 22 in the conversion module 2;

[0109] Step 11: Control the sweep frequency generator 1 to generate a sweep frequency signal of 200KHz-2MHz, and the sweep frequency signal is loaded to the conversion module 2 through the inductor 41 of one of the inductor coil groups 43 among the multiple inductor coil groups 43;

[0110] Step 12: The conversion module 2 converts the current generated by the first inductor coil group 43 into a detection voltage;

[0111] Step 13: The digital-to-analog conversion circuit 7 converts the detection voltage into a digital signal and transmits it to the controller 3;

[0112] Step 14: the controller 3 obtains first information of the digital signal through a discrete Fourier transform digital signal processing algorithm, wherein the first information includes a first complex impedance of the detection voltage, a signal phase of the detection voltage, and a resonant frequency of the detection voltage.

[0113] Step 15: The controller 3 compares the changes in complex impedance, signal phase and resonant frequency on the first inductor coil group when there is / is not a metal foreign object, and determines whether there is a metal foreign object at the transmitting coil module position corresponding to the first inductor coil group 43.

[0114] Wherein, when the capacitor 4 includes multiple inductor coil groups 43, each inductor coil group 43 performs steps 11 to 15 respectively. Since the position of the transmitting coil module corresponding to each inductor coil group 43 is different, multiple inductor coil groups 43 perform steps 11 to 15 respectively, so as to accurately detect whether there is a metal foreign body and the size of the metal foreign body at the transmitting coil module position corresponding to the capacitor 4. Similarly, when the detection module includes multiple capacitors 4, multiple capacitors 4 perform steps 10 to 15 respectively, so as to perform metal foreign body detection on all position areas of the transmitting coil module.

[0115] For the second detection mode, the working process includes:

[0116] Step 20: close the first switch 10 connected to the plurality of inductor coil groups 43 of the capacitor 4, close the third switch 30 connected to the metal frame 42, and close the fifth switch 50 in the conversion module 2 connected to the second resistor 23;

[0117] Step 21: Control the sweep frequency generator 1 to generate a sweep frequency signal of 200KHz~2MHz, and the sweep frequency signal is loaded into the conversion module 2 through the inductor 41 of one of the inductor coil groups 43 and the metal frame 42;

[0118] Step 22: The conversion module 2 converts the current generated by the inductor 41 and the metal frame 42 of an inductor group 43 into a detection voltage;

[0119] Step 23: The digital-to-analog conversion circuit 7 converts the detection voltage into a digital signal and transmits it to the controller 3;

[0120] Step 24: the controller 3 obtains first information of the digital signal through a discrete Fourier transform digital signal processing algorithm, wherein the first information includes a first complex impedance of the detection voltage, a signal phase of the detection voltage, and a resonant frequency of the detection voltage.

[0121] Step 25: the controller 3 compares the changes in complex impedance, signal phase and resonant frequency on the first inductor coil group 43 when there is / is not a living foreign body, and determines whether there is a living foreign body at the transmitting coil module position corresponding to the first inductor coil group 43.

[0122] Wherein, when the capacitor 4 includes multiple inductance coil groups 43, each inductance coil group 43 performs steps 21 to 25 respectively. Since the position of the transmitting coil module corresponding to each inductance coil group 43 is different, multiple inductance coil groups 43 perform steps 21 to 25 respectively, so as to accurately detect whether there is a living foreign body and the size of the living foreign body at the transmitting coil module position corresponding to the capacitor 4. Similarly, when the detection module includes multiple capacitors 4, multiple capacitors 4 perform steps 20 to 25 respectively, so as to perform living foreign body detection on all position areas of the transmitting coil module.

[0123] like Figure 6 As shown, the embodiment of the present disclosure provides a wireless charging system, including:

[0124] The transmitting coil module 200 is used to transmit electric energy to the receiving coil module of the power-consuming object 400 .

[0125] The foreign object detection device 100 of any embodiment of the present disclosure is connected to the transmitting coil module 200 , wherein the detection module of the foreign object detection device corresponds to the coil setting position in the transmitting coil module 200 .

[0126] When explanation is needed:

[0127] Other structures included in the wireless charging system can refer to the wireless charging system in the prior art and are not specifically limited here. Figure 6 As shown, the wireless charging system includes a power supply 300 for supplying power to the transmitting coil module 200, so that the transmitting coil module 200 wirelessly transmits electric energy to the receiving coil module 500 of the power consuming object 400, and the receiving coil module 200 transmits electric energy to the battery 600 of the power consuming object 400, thereby charging the battery 600.

[0128] The foreign object detection device 100 is connected to the transmitting coil module 200 , which can be understood as the foreign object detection device 100 covering the transmitting coil of the transmitting coil module 200 or below, so as to detect foreign objects on the transmitting coil module 200 .

[0129] Figure 7 FIG. 1 is a structural block diagram of an electronic device according to an embodiment of the present disclosure. Figure 7 As shown, the electronic device includes: a memory 710 and a processor 720, and the memory 710 stores a computer program that can be run on the processor 720. The number of the memory 710 and the processor 720 can be one or more. The memory 710 can store one or more computer programs. When the one or more computer programs are executed by the electronic device, the electronic device executes the method provided by the above method embodiment. The electronic device may also include: a communication interface 730, which is used to communicate with external devices and perform data exchange transmission.

[0130] If the memory 710, the processor 720 and the communication interface 730 are implemented independently, the memory 710, the processor 720 and the communication interface 730 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0131] Optionally, in a specific implementation, if the memory 710, the processor 720 and the communication interface 730 are integrated on a chip, the memory 710, the processor 720 and the communication interface 730 can communicate with each other through an internal interface.

[0132] It should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. It is worth noting that the processor may be a processor supporting the Advanced RISC Machines (ARM) architecture.

[0133] Further, optionally, the above-mentioned memory may include a read-only memory and a random access memory, and may also include a non-volatile random access memory. The memory may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may include a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may include a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available. For example, static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM) and direct memory bus random access memory (DR RAM).

[0134] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on the computer, the process or function according to the embodiment of the present disclosure is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (for example: coaxial cable, optical fiber, data subscriber line (Digital Subscriber Line, DSL)) or wireless (for example: infrared, Bluetooth, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that can be accessed by the computer, or a data storage device such as a server or data center that includes one or more available media integrations. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a digital versatile disc (DVD)), or a semiconductor medium (e.g., a solid state disk (SSD)), etc. It is worth noting that the computer-readable storage medium mentioned in the present disclosure may be a non-volatile storage medium, in other words, a non-transient storage medium.

[0135] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0136] In the description of the embodiments of the present disclosure, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0137] In the description of the embodiments of the present disclosure, unless otherwise specified, " / " means or, for example, A / B can mean A or B. "And / or" in this article is only a way to describe the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0138] In the description of the embodiments of the present disclosure, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0139] The above description is only an exemplary embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A foreign body detection device, applied to a wireless charging system, comprising: A sweep frequency signal generator, used for generating a sweep frequency signal; The detection module includes a capacitor composed of an inductor coil and a metal frame, wherein the metal frame is arranged around the periphery of the inductor coil and is not closed along the periphery of the inductor coil to form a gap, and the inductor coil is connected to the sweep signal generator through a first switch; a conversion module, connected to the inductor through a second switch and connected to the metal frame through a third switch, and used for converting the current generated by the detection module into a detection voltage; and A controller, connected to the conversion module, and configured to perform foreign object detection on the transmitting coil module of the wireless charging system according to the detection voltage; Among them, in the first detection mode, the first switch and the second switch are closed, and the third switch is opened, so as to perform foreign object detection of the first category of foreign objects; in the second detection mode, the first switch and the third switch are closed, and the second switch is opened, so as to perform foreign object detection of the second category of foreign objects.

2. The device according to claim 1, wherein: The conversion module includes a transimpedance amplifier, a first resistor and a second resistor, the first resistor is connected to two ends of the transimpedance amplifier through a fourth switch, and the second resistor is connected to two ends of the transimpedance amplifier through a fifth switch; The resistance of the second resistor is of a greater magnitude than that of the first resistor; in the first detection mode, the fourth switch is closed and the fifth switch is open; in the second detection mode, the fifth switch is closed and the fourth switch is open.

3. The device according to claim 1 or 2, wherein: The detection module includes at least one capacitor, each capacitor includes a plurality of inductor coil groups, and the metal frame ring is arranged on the periphery of the plurality of inductor coil groups; The second switch includes multiple second sub-switches, and each inductor group is connected to the conversion module through a second sub-switch; each inductor group includes multiple inductors, and the multiple inductors are respectively used to detect foreign objects in different areas of the transmitting coil module; wherein the multiple inductors are arranged in series or in parallel.

4. The device according to claim 3, wherein: The multiple inductor coils are arranged at intervals, and an inductor coil of another inductor coil group among the multiple inductor coil groups is arranged between two adjacent inductor coils among the multiple inductor coils.

5. The device according to claim 4, wherein: The winding directions of the two adjacent inductor coils are opposite, and / or the winding directions of the two ends of each of the multiple inductor coils are opposite.

6. The device according to claim 3, wherein: The detection module includes a plurality of capacitors, and the plurality of capacitors are used to perform foreign object detection on different areas of the transmitting coil module; The first switch includes a plurality of first sub-switches, and each capacitor is connected to the frequency sweep signal generator via a first sub-switch.

7. A foreign body detection method, applied to the foreign body detection device according to any one of claims 1 to 6, comprising: Determine a detection mode according to the detection instruction, wherein the detection mode includes a first detection mode and / or a second detection mode; According to the detection mode, adjusting the opening and closing states of the first switch, the second switch and the third switch; Controlling the sweep frequency generator to generate a sweep frequency signal; Based on the current generated by the detection module according to the frequency sweep signal, controlling the conversion module to convert the current into a detection voltage; The controller is used to compare the first information in the detection voltage with the threshold information to detect the position and range of the foreign object on the transmitting coil module of the wireless charging system.

8. The method according to claim 7, wherein: The conversion module of the foreign object detection device includes a transimpedance amplifier, a first resistor and a second resistor, wherein the first resistor is connected to both ends of the transimpedance amplifier through a fourth switch, and the second resistor is connected to both ends of the transimpedance amplifier through a fifth switch; wherein the resistance of the second resistor is greater than the resistance of the first resistor; Based on the current generated by the detection module according to the frequency sweep signal, controlling the conversion module to convert the current into a detection voltage includes: According to the detection mode, adjusting the opening and closing states of the fourth switch and the fifth switch to determine the conversion mode of the conversion module; According to the conversion mode, based on the current generated by the detection module according to the sweep signal, the conversion module is controlled to convert the current into a detection voltage.

9. The method according to claim 7, wherein: The first information includes a first complex impedance of the detection voltage, a signal phase of the detection voltage, and a resonant frequency of the detection voltage; The threshold information includes a threshold complex impedance, a threshold signal phase, and a threshold resonant frequency of a signal output by the conversion module when there is no foreign matter on the transmitting coil module.

10. A wireless charging system, comprising: Transmitter coil module, used to transmit electrical energy to the receiving coil module of the power-consuming object ； The foreign object detection device according to any one of claims 1 to 6 is connected to the transmitting coil module, wherein the detection module of the foreign object detection device corresponds to the coil setting position in the transmitting coil module.

11. An electronic device, comprising: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 7 to 9.

12. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to cause the computer to execute the method according to any one of claims 7 to 9.

13. A computer program product, comprising a computer program, which, when executed by a processor, implements the method according to any one of claims 7 to 9.

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