Wireless power transmission metal foreign object detection coil and detection and positioning method

Abstract

The application discloses a wireless power transmission metal foreign object detection coil and a detection and positioning method, and belongs to the technical field of wireless power transmission. S sawtooth coils are transversely spliced to form a transverse detection coil group, wherein S=2T, and T>=1; the transverse detection coil group is rotated by 90 degrees counterclockwise or clockwise along a geometric center to form a longitudinal detection coil group, the transverse detection coil and the longitudinal detection coil group jointly form an overall detection coil, the overall detection coil is composed of 2S sawtooth coils, and covers a charging area of a wireless power transmission system; compared with the prior art, the application can effectively solve the problems that a detection blind area exists for a small metal foreign object in the prior art, or a differential coil detection electric signal is zero and the metal foreign object cannot be effectively detected, and the detection sensitivity is high; while the metal foreign object is detected, the size of the metal foreign object and the position of the metal foreign object can be effectively identified and positioned.

Description

Technical Field

[0001] This invention relates to a wireless power transmission metal foreign object detection coil and a detection and positioning method, belonging to the field of wireless power transmission technology. Background Technology

[0002] Magnetic coupling wireless power transfer technology transmits electrical energy through the strong magnetic coupling resonance principle of the transmitting and receiving coils. During power transfer, if a foreign metallic object or conductive material is placed between the transmitting and receiving coils, it will generate eddy currents in the high-frequency electromagnetic field excited by the transmitting coil, potentially causing overheating or fire hazards, and significantly reducing energy transfer efficiency. Therefore, the detection and location of foreign metallic objects in wireless power transfer is a crucial step in ensuring the safe, reliable, and efficient operation of the energy transfer system.

[0003] Existing related technologies mainly include using planar coil arrays and differential coils for detecting metallic foreign objects.

[0004] Both of the aforementioned traditional techniques suffer from blind spots that prevent effective identification when metallic foreign objects fall into certain specific locations. Summary of the Invention

[0005] To address the aforementioned issues, this invention discloses a wireless power transmission metal foreign object detection coil and a detection and positioning method, which can effectively solve the problem of detection blind spots in traditional technical solutions and accurately locate the position of metal foreign objects.

[0006] To achieve the above objectives, the present invention provides a wireless power transmission metal foreign object detection coil, which is composed of S sawtooth coils horizontally spliced ​​together to form a horizontal detection coil group, wherein S=2T, T≥1;

[0007] The transverse detection coil group is rotated 90° counterclockwise or clockwise around the geometric center to form the longitudinal detection coil group. The transverse and longitudinal detection coil groups together form the overall detection coil, which is composed of 2S sawtooth coils and covers the charging area of ​​the wireless power transmission system.

[0008] Preferably, one side of the contour edge of each of the sawtooth coils is sawtooth-shaped, and the opposite side contour edge is straight-shaped;

[0009] Preferably, the splicing method of S sawtooth coils horizontally spliced ​​together to form a horizontal detection coil group is as follows: every 2 sawtooth coils are placed opposite each other and interlocked along the edge of the sawtooth to form a rectangular structure with a slight gap. T rectangular structures are arranged horizontally to form a horizontal detection coil group.

[0010] Preferably, each sawtooth coil is formed by winding a single wire sequentially from the outside to the inside or from the inside to the outside.

[0011] Preferably, a wire is led out from one side of the sawtooth edge of each sawtooth coil as a zero potential reference point, and the straight edge is used as a signal detection point. The presence of a metal foreign object is determined by observing whether the detection information of each signal detection point exceeds the safety threshold. The size and location of the metal foreign object are determined by observing which of the detection information of each signal detection point exceeds the safety threshold.

[0012] Preferably, the detection information used for the signal detection point includes, but is not limited to, signals such as voltage amplitude, current amplitude, phase difference, and coil impedance;

[0013] Based on the aforementioned wireless power transmission metal foreign object detection coil, the present invention also provides a wireless power transmission metal foreign object detection and location method, the method comprising the following steps:

[0014] Step 1: Apply excitation to the wireless power transmission metal foreign object detection coil;

[0015] Step 2: In the horizontal and vertical detection coil groups, each pair of sawtooth coils that are interlocked along the edge of the sawtooth are grouped together. Each signal detection point is connected to the detection circuit in sequence for signal detection, and the difference in detection information between the two signal detection points in each group of sawtooth coils is recorded.

[0016] Step 3: Compare the difference between the detection information of the two signal detection points in each group of sawtooth coils to see if it is within the safe threshold range of the detection signal. If the difference between the detection information of each group is within the safe threshold range of the detection signal, then there are no metal foreign objects in the charging area of ​​the wireless power transmission system. If there is a difference between the detection information that exceeds the safe threshold range of the detection signal, then there are metal foreign objects in the charging area of ​​the wireless power transmission system. Proceed to Step 4 to further determine the size and location of the metal foreign objects.

[0017] Step 4: Record the signal detection point numbers corresponding to all sawtooth coil groups whose detection information difference exceeds the safe threshold range of the detection signal. The intersection of the sawtooth coil group coverage area corresponding to all recorded horizontal numbers and the sawtooth coil group coverage area corresponding to all recorded vertical numbers is the location of the metal foreign object. The size of the metal foreign object is determined based on the size of the intersection range of the above coverage areas.

[0018] Furthermore, an apparatus includes:

[0019] One or more processors;

[0020] Memory, used to store one or more programs;

[0021] When one or more of the programs are executed by one or more of the processors, the one or more processors implement a wireless power transmission method for detecting and locating metallic foreign objects as described above.

[0022] Furthermore, a storage medium containing computer-executable instructions, which, when executed by a computer processor, are used to perform a wireless power transmission method for detecting and locating metallic foreign objects as described above.

[0023] The beneficial effects of this invention are as follows:

[0024] 1. Compared with the prior art, the present invention can effectively solve the problems of small metal foreign objects having detection blind spots or zero detection electrical signals of differential coils in the existing related technologies, and has high detection sensitivity;

[0025] 2. Compared with the prior art, the present invention can not only detect metal foreign objects, but also effectively identify and locate the size and position of the metal foreign objects.

[0026] 3. Compared with the prior art, the present invention can not only effectively detect and accurately locate metallic foreign objects, but also determine the plane offset of the receiving coil. Moreover, the structure has almost no impact on the transmission characteristics of the magnetically coupled wireless power transmission system and will not cause power loss. Attached Figure Description

[0027] Figure 1 A schematic diagram of a wireless power transmission metal foreign object detection coil provided by the present invention;

[0028] Figure 2 A schematic diagram of a coil for detecting metallic foreign objects using a planar coil array method provided by the present invention;

[0029] Figure 3 A schematic diagram of a differential coil method for detecting metallic foreign objects provided by the present invention;

[0030] Figure 4 A schematic diagram of a wireless power transmission metal foreign object detection coil and a detection and positioning method provided by the present invention;

[0031] List of reference numerals in the attached diagram:

[0032] 1. Horizontal detection coil; 2. Vertical detection coil; 3. Zero potential reference point; 4. Multiple twisted pair shielded wire harness; 5. Twisted pair copper wire. Detailed Implementation

[0033] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0034] It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this invention. These modifications and improvements still fall within the scope of protection of this invention.

[0035] This invention provides a wireless power transmission metal foreign object detection coil and a detection and positioning method. Compared with existing related technologies, it can solve the problems of small metal foreign objects having detection blind spots and the inability to effectively detect them due to zero detection electrical signal of differential coils. It has high detection sensitivity and can effectively identify and locate the size and position of metal foreign objects.

[0036] Figure 1 The present invention provides an overall schematic diagram of a wireless power transmission metal foreign object detection coil, which is composed of S=10 sawtooth coils horizontally spliced ​​together to form a horizontal detection coil group 1, wherein S=2T, T≥1;

[0037] Reference Figure 1 The transverse detection coil group 1 is rotated 90° counterclockwise or clockwise around the geometric center to form the longitudinal detection coil group 2. The transverse detection coil group 1 and the longitudinal detection coil group 2 together form the overall detection coil. There is no gap between the transverse detection coil group 1 and the longitudinal detection coil group 2. The overall detection coil is composed of 2S = 20 sawtooth coils and covers the charging area of ​​the wireless power transmission system. The charging area refers to the area covered by the transmitting coil and the receiving coil. The contour edge of each sawtooth coil is sawtooth-shaped on one side and straight on the opposite side.

[0038] Reference Figure 1 In this embodiment with S=10, 10 sawtooth coils are horizontally spliced ​​together to form the horizontal detection coil group 1. The splicing method is as follows: every 2 sawtooth coils are placed opposite each other, and the sawtooth parts of the 2 sawtooth coils are interlocked along the edge of the sawtooth to form a rectangular structure with a slight gap. The 5 rectangular structures are arranged horizontally to form the horizontal detection coil group 1. Each sawtooth coil is wound sequentially from the outside to the inside or from the inside to the outside by a wire.

[0039] Reference Figure 1 A wire is led out from one side of the sawtooth edge of each sawtooth coil as a zero potential reference point 3, and the straight edge is used as a signal detection point. Among them, A, A', B, B', C, C', D, D', E, E' are signal detection points of the transverse detection coil group, and F, F', G, G', H, H', I, I', J, J' are signal detection points of the longitudinal detection coil group. The presence of a metallic foreign object is determined by observing whether the detection information of each of the above signal detection points exceeds the safety threshold. The size and location of the metallic foreign object are determined by observing which of the detection information of each of the above signal detection points exceeds the safety threshold.

[0040] It should be noted that the detection information used for signal detection points A, A', B, B', C, C', D, D', E, E', F, F', G, G', H, H', I, I', J, J' includes, but is not limited to, signals such as voltage amplitude, current amplitude, phase difference, and coil impedance. In this embodiment, voltage amplitude is selected as the detection information.

[0041] like Figure 2 As shown, a planar coil array is used for metal foreign object detection. The detection circuit determines the presence of a metal foreign object by detecting signals such as the output voltage / current amplitude of the detection coil. However, when the metal foreign object is small, this method has problems such as a detection blind zone or the induced electromotive forces generated by different parts of the detection coil canceling each other out or changing very little.

[0042] like Figure 3 As shown, a differential coil method is used for metal foreign object detection. The detection circuit determines the presence of a metal foreign object by detecting the difference in electrical signals, such as the output voltage at the endpoints of multiple coils. However, when a metal foreign object happens to fall at a point symmetrical about two coil endpoints, the voltage difference may be zero, causing this method to fail to effectively detect the metal foreign object, resulting in a detection blind zone.

[0043] Figure 4 This is a schematic diagram of a wireless power transmission metal foreign object detection coil and a detection and positioning method provided by the present invention.

[0044] by Figure 4 Taking the wireless power transmission metal foreign object detection coil shown as an example, the present invention also provides a wireless power transmission metal foreign object detection and positioning method, the method comprising the following steps:

[0045] Step 1: Apply excitation to the wireless power transmission metal foreign object detection coil;

[0046] Step 2: In the horizontal and vertical detection coil groups, each pair of sawtooth coils, with adjacent edges along the sawtooth edge, forms a rectangular structure and constitutes a group. Signal detection points A, A', B, B', C, C', D, D', E, E', F, F', G, G', H, H', I, I', J, J' are sequentially connected to the detection circuit via multi-twisted shielded wire bundle 4 and twisted copper wire 5 for signal detection. The difference in detection information between the two signal detection points in each group of sawtooth coils is recorded. A -U A′ |、|U B -U B′ |、|U C -U C′ |、|U D -U D′ |、|U E -U E′ |、|U F-U F′ |、|U G -U G′ |、|U H -U H′ |、|U I -U I′ |、|U J -U J′ |;

[0047] Step 3: Compare the difference in detection information between two signal detection points in each group of sawtooth coils |U A -U A′ |、|U B -U B′ |、|U C -U C′ |、|U D -U D′ |、|U E -U E′ |、|U F -U F′ |、|U G -U G′ |、|U H -U H′ |、|U I -U I′ |、|U J -U J′ |Is it within the safe threshold range of the detection signal? If the difference between each set of detection information is within the safe threshold range of the detection signal, then there are no metal foreign objects in the charging area of ​​the wireless power transmission system. If the difference between the detection information exceeds the safe threshold range of the detection signal, then there are metal foreign objects in the charging area of ​​the wireless power transmission system. Proceed to step 4 to further determine the size and location of the metal foreign objects.

[0048] Step 4: Record the signal detection point numbers corresponding to all sawtooth coil groups (including horizontal and vertical detection coil groups) whose detection information difference exceeds the detection signal safety threshold range. The intersection of the coverage areas of all recorded horizontal sawtooth coil groups and the coverage areas of all recorded vertical sawtooth coil groups is the location of the metal foreign object. The size of the metal foreign object is determined based on the size of the intersection area. Taking the recorded detection point numbers A, A', F, and F' as an example, the location of the metal foreign object is determined to be within the intersection area of ​​the horizontal sawtooth coil group coverage areas corresponding to A and A' and the vertical sawtooth coil group coverage areas corresponding to F and F'.

[0049] In summary, the wireless power transmission metal foreign object detection coil and detection and positioning method provided by the embodiments of the present invention have the following beneficial effects:

[0050] 1. Compared with the prior art, the present invention can effectively solve the problems of small metal foreign objects having detection blind spots or zero detection electrical signals of differential coils in the existing related technologies, and has high detection sensitivity;

[0051] 2. Compared with the prior art, the present invention can not only detect metal foreign objects, but also effectively identify and locate the size and position of the metal foreign objects.

[0052] 3. Compared with the prior art, the present invention can not only effectively detect and accurately locate metallic foreign objects, but also determine the plane offset of the receiving coil. Moreover, the structure has almost no impact on the transmission characteristics of the magnetically coupled wireless power transmission system and will not cause power loss.

[0053] The advantages of this invention compared with existing related technologies are shown in Table 1.

[0054] Planar coil array method Differential coil method This invention Are there any blind spots in detection? There are blind spots in detection. There are blind spots in detection. No detection blind spots Can the location of the foreign object be located? no no yes

[0055] Based on the same inventive concept, the present invention also provides a computer device, which includes: one or more processors and a memory for storing one or more computer programs; the program includes program instructions, and the processor is used to execute the program instructions stored in the memory. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., which are the computing core and control core of the terminal, and are used to implement one or more instructions, specifically for loading and executing one or more instructions in the computer storage medium to implement the above-mentioned method.

[0056] It should be further explained that, based on the same inventive concept, the present invention also provides a computer storage medium storing a computer program, which, when executed by a processor, performs the above-described method. This storage medium can be any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In the present invention, the computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0057] It should be noted that the above content merely illustrates the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. For those skilled in the art, various improvements and modifications can be made without departing from the principle of the present invention, and all such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A wireless power transmission metallic foreign object detection coil, characterized in that, It includes a horizontal detection coil group consisting of S sawtooth coils horizontally spliced ​​together, where S = 2T, T ≥ 1; the horizontal detection coil group is rotated 90° counterclockwise or clockwise around the geometric center to form a vertical detection coil group, and the horizontal detection coil group and the vertical detection coil group together form an overall detection coil, which is composed of 2S sawtooth coils and covers the charging area of ​​the wireless power transmission system; Each of the serrated coils has a serrated edge on one side and a straight edge on the opposite side. The horizontal detection coil group is formed by splicing S sawtooth coils horizontally. The splicing method is as follows: every 2 sawtooth coils are placed opposite each other and interlocked along the edge of the sawtooth to form a rectangular structure with a slight gap. T rectangular structures are arranged horizontally to form a horizontal detection coil group. Each of the aforementioned sawtooth coils is formed by winding a single wire sequentially from the outside to the inside or from the inside to the outside. A wire is led out from one side of the sawtooth edge of each sawtooth coil as a zero potential reference point, and the straight edge side is used as a signal detection point. The presence of a metal foreign object is determined by observing whether the detection information of each signal detection point exceeds the safety threshold. The size and location of the metal foreign object are determined by observing which of the detection information of each signal detection point exceeds the safety threshold.

2. The wireless power transmission metallic foreign object detection coil according to claim 1, characterized in that, The detection information used for signal detection points includes, but is not limited to, voltage amplitude, current amplitude, phase difference, and coil impedance.

3. A method for detecting and locating metallic foreign objects based on the wireless power transmission metallic foreign object detection coil according to any one of claims 1-2, characterized in that, Includes the following steps: Excitation is applied to the wireless power transmission metal foreign object detection coil; In the transverse and longitudinal detection coil groups, each pair of sawtooth coils that are interlocked along the edge of the sawtooth are grouped together. Each signal detection point is connected to the detection circuit in sequence for signal detection, and the difference in detection information between the two signal detection points in each group of sawtooth coils is recorded. Compare the difference between the detection information of the two signal detection points in each group of sawtooth coils to see if it is within the safe threshold range of the detection signal; if the difference between the detection information of each group is within the safe threshold range of the detection signal, then there are no metal foreign objects in the charging area of ​​the wireless power transmission system; if there is a difference between the detection information that exceeds the safe threshold range of the detection signal, then there are metal foreign objects in the charging area of ​​the wireless power transmission system. Record the signal detection point numbers corresponding to all sawtooth coil groups whose detection information difference exceeds the safe threshold range of the detection signal. The intersection of the sawtooth coil group coverage area corresponding to all recorded horizontal numbers and the sawtooth coil group coverage area corresponding to all recorded vertical numbers is the location of the metal foreign object. The size of the metal foreign object is determined based on the size of the intersection range of the above coverage areas.

4. A device, characterized in that, The device includes: One or more processors; Memory, used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors perform the detection and localization method as described in claim 3.

5. A computer-readable storage medium storing a computer program, characterized in that, When the program is executed by the processor, it implements the detection and localization method as described in claim 3.

Images