CN115826057A - Detection device, system and method for metal foreign matters - Google Patents

Abstract

The embodiment of the invention discloses a device, a system and a method for detecting metal foreign matters. The detection device for the metal foreign matters is used for detecting the metal foreign matters on a coil plate at a transmitting end in a wireless charging system, is arranged in the coil plate and comprises a plurality of groups of metal wires and backing plates which are sequentially connected end to end; the multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd-number points and even-number points, the odd-number points and the even-number points are respectively located on two sides of the base plate, the multi-group metal wires penetrate through the base plate, and the two ends of any one group of metal wires are respectively the odd-number points and the even-number points. The detection device, the detection system and the detection method for the metal foreign matters provided by the embodiment of the invention can improve the detection efficiency.

Description

Detection device, system and method for metal foreign matters

Technical Field

The embodiment of the invention relates to a metal foreign matter detection technology, in particular to a metal foreign matter detection device, system and method.

Background

The wireless charging system of new energy automobile, robot usually comprises transmitting terminal, receiving terminal. The coil plate of the transmitting terminal is placed on the ground surface of the charging position or embedded in the ground, and foreign matters are easily accumulated on the surface. When the foreign matter is the metal, for example key, coin etc. can produce induced-current in charging process, and the heat that accumulates simultaneously heaies up, can produce the potential safety hazard when influencing the charging effect. Therefore, the coil plate of the transmitting end needs to be subjected to metal foreign matter detection. At present, the detection device of the existing metal foreign matter generally needs manual assistance when detecting the metal foreign matter, and the detection efficiency is influenced.

Disclosure of Invention

The embodiment of the invention provides a device, a system and a method for detecting a metal foreign body, which aim to improve the detection efficiency.

In a first aspect, an embodiment of the present invention provides a device for detecting a metallic foreign object, where the device is used to detect a metallic foreign object on a coil plate at a transmitting end in a wireless charging system, and the device is disposed in the coil plate and includes multiple groups of wires and backing plates connected end to end in sequence;

the multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd-number points and even-number points, the odd-number points and the even-number points are respectively located on two sides of the base plate, the multi-group metal wires penetrate through the base plate, and the two ends of any one group of metal wires are respectively the odd-number points and the even-number points.

The detection device of metallic foreign matter that this embodiment provided, multiunit wire end to end's tie point in proper order includes odd number point and even number point, and odd number point and even number point are located the both sides of backing plate respectively, can detect whether there is metallic foreign matter according to the voltage difference at multiunit wire both ends, realize the detection to metallic foreign matter, compare with current needs artifical supplementary detection mode, can improve detection efficiency.

Optionally, in the tangent plane of the backing plate, the arrangement of the plurality of groups of metal wires includes at least one of a zigzag, a rectangular and a trapezoid.

Optionally, the number of the plurality of groups of wires is odd.

Optionally, the plurality of groups of metal wires include metal wires having seebeck coefficients of two different values.

Optionally, the difference between the two different values is greater than 10uV/K.

Optionally, the material of the backing plate is a non-conductor non-electromagnetic induction material.

Optionally, both sides of the backing plate are coated with a thermally conductive material.

In a second aspect, an embodiment of the present invention provides a system for detecting a metallic foreign object, including the detection device of the first aspect, further including an acquisition module and a control module, where the acquisition module is electrically connected to the control module and the detection device, the acquisition module is configured to acquire voltages at two ends of a plurality of groups of metal wires in the detection device, and the control module is configured to determine whether there is a metallic foreign object according to the voltages.

In a third aspect, an embodiment of the present invention provides a method for detecting a metal foreign object, where the method is performed by a control module in the detection system according to the second aspect, and the method includes:

receiving the voltage transmitted by the acquisition module;

and determining whether the metal foreign matters exist or not according to the voltage.

Optionally, determining whether there is a metal foreign object according to the voltage includes:

and if the change of the voltage exceeds a preset change range, determining that metal foreign matters exist.

The detection device is used for detecting the metal foreign matters on a coil plate at a transmitting end in a wireless charging system, the detection device is arranged in the coil plate, and the detection device comprises a plurality of groups of metal wires and base plates which are sequentially connected end to end; the multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd-number points and even-number points, the odd-number points and the even-number points are respectively located on two sides of the base plate, the multi-group metal wires penetrate through the base plate, and the two ends of any one group of metal wires are respectively the odd-number points and the even-number points. According to the detection device, the detection system and the detection method for the metal foreign bodies, provided by the embodiment of the invention, the connection points of the multiple groups of metal wires which are sequentially connected end to end comprise odd points and even points, the odd points and the even points are respectively positioned at two sides of the base plate, whether the metal foreign bodies exist can be detected according to the voltage difference of two ends of the multiple groups of metal wires, the detection of the metal foreign bodies is realized, and compared with the existing detection mode needing manual assistance, the detection efficiency can be improved.

Drawings

Fig. 1 is a sectional view of a device for detecting metallic foreign matter according to an embodiment of the present invention;

FIG. 2 is a schematic view of a wire according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of another apparatus for detecting metallic foreign objects according to an embodiment of the present invention;

FIG. 4 is a top view corresponding to FIG. 3;

FIG. 5 is a cross-sectional view of another apparatus for detecting metallic foreign objects according to an embodiment of the present invention;

FIG. 6 is a top view corresponding to FIG. 5;

FIG. 7 is a schematic view of another wire provided by an embodiment of the present invention;

fig. 8 is a flowchart of a method for detecting a metal foreign object according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Fig. 1 is a cross-sectional view of a device for detecting a metal foreign object according to an embodiment of the present invention. Referring to fig. 1, the detection device for the metallic foreign matter is used for detecting the metallic foreign matter on the coil plate of the transmitting terminal in the wireless charging system, the detection device is arranged in the coil plate, and the detection device comprises a plurality of groups of metal wires and a backing plate 1 which are sequentially connected end to end.

The multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd-number points and even-number points, the odd-number points and the even-number points are respectively located on two sides of the base plate, the multi-group metal wires penetrate through the base plate 1, and the two ends of any one group of metal wires are respectively the odd-number points and the even-number points.

Specifically, fig. 1 illustrates 11 groups of metal wires, wherein the 11 groups of metal wires have a seebeck coefficient of B ₁ And B ₂ Of (2) a metalAnd (4) silk. The 11 groups of wires have 10 connection points, wherein the odd number points and the even number points are 5. The positions corresponding to the temperatures T3, T5, T7, T9, and T11 are odd-numbered points, and the positions corresponding to the temperatures T2, T4, T6, T8, and T10 are even-numbered points. The positions corresponding to the temperatures T1 and T12 are two end positions of the 11 groups of metal wires respectively, the two end positions are respectively positioned at two sides of the base plate and are far away from a signal processing circuit area of the metal foreign matter detection area, and the two end positions can also be respectively used as odd points and even points. Illustratively, fig. 2 is a schematic view of a wire according to an embodiment of the present invention. Referring to fig. 2, the two groups of metal wires in fig. 2 are metal wires with seebeck coefficients B1 and B2, respectively, and the metal wires of B1 and B2 are connected in sequence. The seebeck coefficient can be regarded as a constant within a certain temperature range, and B1 and B2 can be regarded as constants within the temperature variation range in the embodiment of the present invention. If the coil plate of the detection device has metal foreign matter, the metal is exposed to a strong magnetic field to generate heat, which causes the temperature T01 and the temperature T02 in fig. 2 to be different. In fig. 2, the voltage difference V1-V2= B1 (T02-T01) + B2 (T01-T02) = (B1-B2) (T02-T01) at both ends of the wire, and as can be seen from the above voltage difference formula, when the temperature T01 is not equal to T02, the voltage difference V1-V2 at both ends of the wire is not zero, so that when the voltage difference V1-V2 at both ends of the wire is not zero, it can be determined that the coil plate where the detection device is located has a metal foreign object. Similarly, for the 11 groups of wires in fig. 1, if the odd point temperature Todd is equal, the even point temperature Teven is equal, or the temperatures at the two ends of the 11 groups of wires are equal, the voltage difference V + -V- = N (B1-B2) (Todd-Teven) + B2 (T12-T1) at the two ends of the 11 groups of wires. The corresponding connection points of T1 and T12 are measurement points of the signal processing circuit, and it is generally easier to ensure that the temperatures of the two points are the same, i.e., T12-T1=0, so V + -V- = N (B1-B2) (Todd-Teven). However, since the metal foreign object detection area, i.e., the area where Todd and Teven are located, may be in a high temperature or low temperature environment, and the signal processing circuit may cause measurement deviation in these extreme environments, the measurement points, i.e., the connection points, corresponding to T1 and T12 may be disposed in a normal temperature environment far from the detection area. In practical application, because the detection process of the detection device has various factors, even if no metal foreign matter exists, toddThe Teven still can not be zero, so the voltage difference V + -V-is not zero, and because the temperature rise of the metal foreign matters in the strong magnetic field is far more than the imbalance of the temperature under the normal working condition, whether the metal foreign matters exist on the coil plate where the detection device is located can be determined according to the change of the voltage difference V + -V-. For example, if the change of the voltage difference V + -V-exceeds the preset change range, if the difference between the voltage difference at the current moment and the voltage difference at the previous moment exceeds the preset change range, it is determined that there is a metal foreign object, and thus the detection of the metal foreign object is realized.

The detection device for the metal foreign matters is used for detecting the metal foreign matters on the coil plate of the transmitting end in the wireless charging system, the detection device is arranged in the coil plate, and the detection device comprises a plurality of groups of metal wires and backing plates which are sequentially connected end to end; the multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd-number points and even-number points, the odd-number points and the even-number points are respectively located on two sides of the base plate, the multi-group metal wires penetrate through the base plate, and the two ends of any one group of metal wires are respectively the odd-number points and the even-number points. The detection device of metallic foreign matter that this embodiment provided, multiunit wire end to end's tie point in proper order includes odd number point and even number point, and odd number point and even number point are located the both sides of backing plate respectively, can detect whether there is metallic foreign matter according to the voltage difference at multiunit wire both ends, realize the detection to metallic foreign matter, compare with current needs artifical supplementary detection mode, can improve detection efficiency.

Optionally, in the tangent plane of the backing plate 1, the arrangement of the plurality of groups of metal wires includes at least one of a zigzag shape, a rectangular shape and a trapezoidal shape.

Specifically, the plurality of sets of wires shown in fig. 1 are arranged in a zigzag manner. Exemplarily, fig. 3 is a cross-sectional view of another metal foreign object detection apparatus provided in an embodiment of the present invention, and fig. 4 is a top view corresponding to fig. 3. Referring to fig. 3 and 4, the plurality of sets of wires are arranged in a rectangular shape. Fig. 5 is a sectional view of another metal foreign matter detection apparatus according to an embodiment of the present invention, and fig. 6 is a top view corresponding to fig. 5. Referring to fig. 5 and 6, the plurality of sets of wires are arranged in a trapezoidal shape.

It should be noted that the various arrangement modes of the metal wires are only schematic illustrations, and may be set according to actual detection requirements, and are not limited herein.

Optionally, the number of the plurality of groups of wires is odd.

Illustratively, fig. 7 is a schematic view of another wire provided by an embodiment of the present invention. Fig. 7 shows 10 groups of wires, where V + -V- = (B1-B2) (Σ Todd- Σ teren) when the temperature T1= T11, and V + -V- = N (B1-B2) (Todd-teren) when the odd-numbered spot temperatures are the same and the even-numbered spot temperatures are also the same, where N is the number of wires connected in series. Fig. 7 shows that the wires with seebeck coefficients B1 and B2 are connected in sequence, and the measurement points corresponding to T1 and T11 need to be located in the metal foreign object detection region and need to be as close as possible to ensure that the temperatures of the two points are the same. And extreme temperature environments such as high temperature or low temperature may appear in the detection area, which is not favorable for the stable operation of the detection circuit. If the measuring points corresponding to T1 and T11 are brought into a normal temperature environment far away from the detection area, the measurement voltage V + -V-will be greatly deviated, therefore, the detection device adopts odd groups of metal wires such as 11 groups of metal wires shown in fig. 1, the measuring points corresponding to T1 and T12 are far away from the temperature measurement area and are close to each other, and the temperature difference is negligible.

Optionally, the plurality of groups of metal wires include metal wires having seebeck coefficients of two different values.

Specifically, as can be seen from the formula of the voltage difference V + -V-, a wire having a seebeck coefficient of at least two different values is required to determine whether a detection result, i.e., whether there is a metallic foreign object, according to the voltage difference V + -V-. Because the complexity of the wire selection is increased when the seebeck coefficient is three or four or more different values, the wire with the seebeck coefficient of two different values, such as B1 and B2, can be used in order to facilitate the wire selection, thereby reducing the complexity of the wire selection while ensuring the detection result.

Optionally, the difference between the two different values is greater than 10uV/K.

Illustratively, referring to FIG. 1, since the voltage difference V + -V-is in millivolts, the voltage difference V + -V-needs to be increased as much as possible for convenient detection and improved detection sensitivity. As can be seen from the above formula of voltage difference V + -V-, the larger B1-B2 is, the larger voltage difference V + -V-is, the easier it is to detect. Therefore, two kinds of metal wires with large difference of seebeck coefficients are adopted. Such as tungsten (having a seebeck coefficient of 7.5uV/K with respect to platinum) and nickel (having a seebeck coefficient of-15 uV/K with respect to platinum), or tungsten and constantan (having a seebeck coefficient of-35 uV/K with respect to platinum), or copper (having a seebeck coefficient of 6.5uV/K with respect to platinum) and nickel, or copper and constantan, or aluminum (having a seebeck coefficient of 3.5uV/K with respect to platinum) and nickel, or aluminum and constantan, etc., so that the seebeck coefficients differ greatly, thereby increasing the voltage difference V + -V-, to facilitate detection and improve detection sensitivity.

Optionally, the material of the backing plate 1 is a non-conductor non-electromagnetic induction material.

Specifically, for example, the detection device is located in a coil plate of the transmitting end of the wireless charging system, the pad plate 1 in the detection device is located between strong magnetic fields, and if the pad plate 1 is conductive or electromagnetic induction occurs, wireless transmission of the wireless charging system may be directly affected. Therefore, the backing plate 1 needs to be a non-conductive non-electromagnetic induction material such as: glass fiber board, bakelite board, polycarbonate plastics, nylon plastics etc to guarantee that wireless charging system can normally carry out wireless transmission.

Optionally, both sides of the backing plate 1 are coated with a heat conductive material. Specifically, the two sides of the backing plate 1 are coated with heat conducting materials such as epoxy resin, so that the effects of reinforcing metal wires, increasing the insulation level, increasing the temperature balance and the like can be achieved.

The detection device for the metal foreign matters is used for detecting the metal foreign matters on the coil plate of the transmitting end in the wireless charging system, the detection device is arranged in the coil plate, and the detection device comprises a plurality of groups of metal wires and backing plates which are sequentially connected end to end; the multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd-number points and even-number points, the odd-number points and the even-number points are respectively located on two sides of the base plate, the multi-group metal wires penetrate through the base plate, and the two ends of any one group of metal wires are respectively the odd-number points and the even-number points. The detection device of metallic foreign matter that this embodiment provided, multiunit wire end to end's tie point in proper order includes odd number point and even number point, and odd number point and even number point are located the both sides of backing plate respectively, can detect whether there is metallic foreign matter according to the voltage difference at multiunit wire both ends, realize the detection to metallic foreign matter, compare with current needs artifical supplementary detection mode, can improve detection efficiency.

The embodiment also provides a detection system for the metal foreign bodies, which comprises the detection device disclosed by any embodiment of the invention, and further comprises an acquisition module and a control module, wherein the acquisition module is electrically connected with the control module and the detection device, the acquisition module is used for acquiring voltages at two ends of a plurality of groups of metal wires in the detection device, and the control module is used for determining whether the metal foreign bodies exist according to the voltages.

Specifically, the acquisition module in the detection system can be electrically connected with two ends of a plurality of groups of metal wires in the detection device, and the acquisition module can acquire the voltages at the two ends of the plurality of groups of metal wires in real time, such as the voltage difference V + -V-, and transmit the acquired voltages to the control module. The control module can determine whether the metal foreign matter exists according to the voltage acquired by the acquisition module in real time, and if the voltage at the current moment is compared with the voltage at the previous moment and the change exceeds a preset change range, the metal foreign matter can be determined, the wireless charging system stops charging starting or proceeding, and the control module can also send a corresponding prompt to prompt related personnel to take corresponding measures in time.

The detection system for the metal foreign matter provided by the embodiment of the invention and the detection device for the metal foreign matter provided by any embodiment of the invention belong to the same inventive concept, and have corresponding beneficial effects, and detailed technical details of the detection system for the metal foreign matter provided by any embodiment of the invention are not shown in the detailed technical details of the embodiment of the invention.

The embodiment further provides a method for detecting a metal foreign object, and fig. 8 is a flowchart of the method for detecting a metal foreign object according to the embodiment of the present invention. The detection method is executed by a control module in the detection system according to any embodiment of the invention, and comprises the following steps:

and step 110, receiving the voltage transmitted by the acquisition module.

The voltage transmitted by the acquisition module is the voltage at two ends of a plurality of groups of metal wires in the detection device, such as the voltage difference V + -V-.

And step 120, determining whether metal foreign matters exist or not according to the voltage.

Specifically, if the change of the voltage exceeds the preset change range, the detection result is determined to be the presence of the metal foreign matter, and if the change of the voltage does not exceed the preset change range, the detection result is determined to be the absence of the metal foreign matter. And after the control module determines the detection result, the wireless charging system stops charging starting or proceeding, and the control module can also send out a corresponding prompt.

The method for detecting the metal foreign matter provided by the embodiment of the invention and the device for detecting the metal foreign matter provided by any embodiment of the invention belong to the same inventive concept, and have corresponding beneficial effects, and detailed technical details of the method for detecting the metal foreign matter provided by any embodiment of the invention are not shown in the detailed technical details of the embodiment of the invention.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements, combinations and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims (10)

1. The detection device for the metal foreign matters is characterized by being used for detecting the metal foreign matters on a coil plate at a transmitting end in a wireless charging system, being arranged in the coil plate and comprising a plurality of groups of metal wires and backing plates which are sequentially connected end to end;

the multi-group metal wires comprise metal wires with different Seebeck coefficients, connecting points of the multi-group metal wires which are sequentially connected end to end comprise odd points and even points, the odd points and the even points are respectively located on two sides of the backing plate, the multi-group metal wires penetrate through the backing plate, and the two ends of any one group of metal wires are respectively the odd points and the even points.

2. The detecting device for detecting the rotation of a motor rotor as claimed in claim 1, wherein the arrangement of the plurality of sets of wires includes at least one of a zigzag shape, a rectangular shape and a trapezoidal shape in a section of the pad plate.

3. The sensing device of claim 1, wherein the plurality of sets of wires is an odd number.

4. The sensing device of claim 1, wherein the plurality of sets of wires comprise wires having seebeck coefficients of two different values.

5. The detection device according to claim 4, wherein the difference between the two different values is greater than 10uV/K.

6. The detecting device for detecting the rotation of a motor rotor as claimed in claim 1, wherein the material of the pad plate is a non-conductor non-electromagnetic induction material.

7. The detecting device for detecting the rotation of a motor rotor as claimed in claim 1, wherein both sides of the pad plate are coated with a heat conductive material.

8. A detection system for metal foreign bodies, which is characterized by comprising the detection device as claimed in any one of claims 1 to 7, and further comprising an acquisition module and a control module, wherein the acquisition module is electrically connected with the control module and the detection device, the acquisition module is used for acquiring the voltage at two ends of the multiple groups of metal wires in the detection device, and the control module is used for determining whether metal foreign bodies exist according to the voltage.

9. A detection method of a metallic foreign object, characterized in that the detection method is performed by a control module in the detection system according to claim 8, the detection method comprising:

receiving the voltage transmitted by the acquisition module;

and determining whether metal foreign matters exist or not according to the voltage.

10. The method of claim 9, wherein said determining whether there is a metallic foreign object based on said voltage comprises:

and if the change of the voltage exceeds a preset change range, determining that metal foreign matters exist.

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