CN211148940U

CN211148940U - Wireless charging system and foreign matter detection equipment thereof

Info

Publication number: CN211148940U
Application number: CN201922048952.1U
Authority: CN
Inventors: 王哲; 贺凡波; 陆钧; 葛俊杰; 马俊超
Original assignee: Beijing Invispower Co Ltd
Current assignee: Hefei Yougan Technology Co.,Ltd.
Priority date: 2019-11-22
Filing date: 2019-11-22
Publication date: 2020-07-31
Anticipated expiration: 2029-11-22

Abstract

The utility model discloses a wireless charging system and foreign matter check out test set thereof, wireless charging system's foreign matter check out test set includes: the detection coil set comprises a plurality of coil groups; the detection module detects the impedance of each coil group in sequence; the coil group is provided with at least two symmetrical coils, each coil is formed by winding a conductor, and the winding directions of the two symmetrical coils are opposite. The utility model discloses a wireless charging system and foreign matter check out test set thereof detects the impedance of every coil assembly through detection module to change through impedance realizes the detection to the foreign matter. This way, the detection accuracy is higher.

Description

Wireless charging system and foreign matter detection equipment thereof

Technical Field

The utility model relates to a wireless field of charging especially relates to wireless charging system and foreign matter check out test set thereof.

Background

The wireless charging technology of the electric automobile has the characteristics of safety, environmental protection, convenience and quickness in use and the like, and along with the gradual popularization of the technologies such as automatic parking, automatic driving, intelligent internet automobiles and the like, the wireless charging is widely regarded as an automatic charging mode with great advantages. However, when a metal foreign object appears above a transmitting coil of the wireless charging system, the metal foreign object generates heat due to an eddy current effect, which seriously affects transmission of system electric energy and may even cause a safety hazard due to a sharp rise in temperature. Therefore, the metal foreign object detection is an important protection function necessary for the wireless charging transmitting coil and the wireless charging technology. When the wireless charging is carried out, besides the influence of entering of foreign matters, the position alignment of the receiving coil and the transmitting coil is ensured when the vehicle is parked, so that the charging efficiency is improved.

In the prior art, a plurality of parallel detection coils are generally used, and the detection coils are arranged between a transmitting coil and a receiving coil and are arranged on the inner side of the plane where an energy transmitting coil is located. When foreign matters exist, the current or voltage or the phase of the foreign matter detection coil changes, and the foreign matter detection sensor detects the foreign matters according to the change of the current or voltage or the phase of the foreign matter detection coil. Of course, the foreign matter mentioned here mainly refers to metal foreign matter, and of course, foreign matter of other conductive materials is also included.

When foreign matter exists at adjacent edges of the plurality of coils, there is a problem of missing detection. Meanwhile, the detection coil is placed on the transmitting coil, generates current and voltage through electromagnetic induction with the transmitting coil, and detects foreign matter by detecting the current and voltage changes when the foreign matter enters, but the detection mode has low precision and the detection result is greatly interfered.

SUMMERY OF THE UTILITY MODEL

The utility model provides a wireless charging system and foreign matter check out test set thereof can be simple accurate judge the foreign matter.

The utility model discloses a wireless charging system's foreign matter check out test set, include: the detection coil set comprises a plurality of coil groups; the detection module detects the impedance of each coil group in sequence; the coil group is provided with at least two symmetrical coils, each coil is formed by winding a conductor, and the winding directions of the two symmetrical coils are opposite.

Preferably, the detection coil sets are at least two and are superposed with each other; the uncovered area of the coil group in one of the detection coil sets is in the covered area of the coil group in the other detection coil set.

Preferably, still include the switch module, the switch module connect in detect between coil assembly and the detection module, control every coil assembly in proper order with detection module UNICOM.

Preferably, the detection module further comprises a filtering module, and the filtering module is connected between the switch module and the detection module.

Preferably, the detection module is an impedance detection circuit.

Preferably, the detection device further comprises a power supply, wherein the power supply at least supplies power to the detection module and each coil group.

The utility model also provides a wireless charging system, including transmitting coil and shell, still include foretell wireless charging system's foreign matter check out test set, wireless charging system's foreign matter check out test set up transmitting coil with between the shell.

The utility model discloses a wireless charging system and foreign matter check out test set thereof detects the impedance of every coil assembly through detection module to change through impedance realizes the detection to the foreign matter. This way, the detection accuracy is higher.

Drawings

Fig. 1 is the utility model discloses wireless charging system's foreign matter check out test set's schematic diagram.

Fig. 2 is a schematic diagram between coil sets in the foreign object detection device of the wireless charging system.

Fig. 3 is another schematic diagram between coil sets in the foreign object detection device of the wireless charging system of the present invention.

Reference numerals:

the device comprises a detection coil set 1, a detection module 2, a switch module 3, a filtering module 4, a power supply 5, a coil group 11 and a coil 110.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present invention, and should not be construed as limiting the present invention.

The utility model discloses a wireless charging system and this wireless charging system's foreign matter check out test set. The foreign object detection apparatus of the wireless charging system will be explained first.

Referring to fig. 1, the foreign object detection apparatus (hereinafter, referred to as a detection apparatus) of the wireless charging system includes a detection coil set 1 and a detection module 2.

The detection coil set 1 blocks a plurality of coil groups 11, and the detection coil set 1 is a set of the coil groups 11, and extends the detection direction thereof in a planar arrangement. The detection module 2 detects the impedance of each coil group 11, and generally detects each coil group 11 in turn, so as to obtain the impedance of each coil group 11, and when a foreign object is detected, the position of the foreign object can be determined according to the detection sequence. It should be noted that the references to "sequentially detecting" herein do not necessarily follow the adjacency as a unique order, but rather a fixed order, or an order that can be recorded. The purpose is to be able to ascertain which coil set 11, or the impedance changes of those coil sets 11, when a foreign object is detected, to determine the location of the foreign object. The detection module 2 may use an impedance detector directly or may use an impedance detection circuit.

The coil assembly 11 has at least two symmetrical coils 110, and the coils 110 are formed by winding a conductor, and the winding directions of the two symmetrical coils 110 are opposite. The coils 110 are typically two-fold, e.g., 2, 4, and are symmetrically positioned. When there are a plurality of first turns 110, the winding directions of two coils 110 that are position-symmetrical to each other are opposite.

The detection coil sets 1 described above have at least two, and are arranged one above the other. The uncovered area of the coil group 11 in one of the detection coil sets 1 is within the covered area of the coil group 11 in the other detection coil set 1. For convenience of explanation, we will refer to one of the detection coils 1 as a first coil set, and the other detection coil set 1 as a second coil set. There is a recognition dead zone between the respective coil groups 11 of the first coil set, which is covered by the second coil set. As shown in fig. 2 and 3, in this more regular wiring manner (arrangement of the coil groups 11), there is a non-coverage area between adjacent coil groups 11, and a circular coil 110 is shown in the figure, so that the non-coverage area is larger. This non-covered area, called the identification blind, is indicated by the arrow Z in the figure. The dead zone of the first set of coils is located within the coverage area of the second set of coils, i.e. within the identified area of the second set of coils. In this way, foreign objects entering the identification blind area of the second coil set are also identified by the first coil set. As can be understood from fig. 2 and 3, the coil 110 has a square, circular or other shape, and has a blind area at an adjacent position. Fig. 1 shows two detection coil sets 1 only for convenience, and does not show the overlapping relationship between two or more detection coil sets 1.

Generally, the coil 110 is wound, and a round angle is inevitably formed due to the thickness (diameter) of the wire harness, as shown in fig. 3, even if a square coil has a radian at four corners, signals of a plurality of coils generate cross interference, a dead zone occurs at a boundary portion, and what is shown by an arrow Z in fig. 3 is the dead zone. Referring to fig. 3, a plurality of dead zones exist at the junctions of the plurality of coil groups 11, and the dead zones are covered by another coil set (shown in a dotted line for distinction in the drawing) which is stacked. It should be noted that fig. 3 is only an illustration and is not intended to limit the shape, arrangement, number, etc. of the second coil set and the first coil concentration coil set 11.

It is to be noted that in fig. 2 and 3, in order to distinguish the coil groups 11 in the different detection coil sets 1, the coil group 11 in one of the detection coil sets 1 is shown by a broken line, and the corresponding index finger line is also shown by a broken line. The two detection coil sets 1 in fig. 1 are shown in a parallel manner for convenience of expression, and do not indicate that they are arranged in this relationship.

For the purposes of the above description, a first coil set and a second coil set are introduced, and in practical application, without distinction, the non-coverage area of any one coil set is within the coverage area of another coil set. That is, at least two coil sets are overlapped, so that no blind area exists in the range needing to be detected. And the blind area does not influence the scheme outside the range needing to be detected. The coil set is typically arranged over a range greater than the area to be detected.

In addition to the above structure, the foreign object detection apparatus of the wireless charging system of the present application further includes a switch module 3 and a filter module 4.

The switch module 3 is connected between the detection coil set 1 and the detection module 2, and controls each coil set 11 to be communicated with the detection module 2 in sequence. The filtering module 4 is connected between the switching module 3 and the detection module 2. Preferably, in one embodiment, the detection coil set 1 is communicated to the filtering module 4 through the switching module 3, the switching module 3 controls the coil groups 11 in the detection coil set 1 to be communicated to the filtering module 4 one by one, and the filtering module 4 filters each coil group 11 one by one and sends the filtered signal to the detection module 2.

As shown in fig. 1, since the detection coil set 1 has a plurality of detection coil sets, each detection coil set 1 may be connected with a switch module 3, each switch module 3 is also connected with a filter module 4, and all the filter modules are connected to the detection module 2 in common. All the detection coil sets 1 may also share one switch module 3, and certainly, only one subsequent filter module 4 is used correspondingly.

The filtering module 4 mainly filters the influence of the transmitting coil in the wireless charging system. In the application, the detection equipment of this application sets up in the top of transmitting coil to the wireless charging of car is the example, and this detection equipment sets up in the ground end, is located transmitting coil top. The coil assembly 11 is now affected by the transmitter coil, so that the filter module 4 functions as: the coil assembly 11 is filtered out due to the electrical signal formed by the electromagnetic induction with the transmitting coil. Filtering at different frequencies can be used here to filter out the influencing signals generated by the transmitter coil. That is to say the frequency of the coil set 11 itself is different from the frequency applied by the transmitting coil.

The filtering module 4 can filter out the influence of the transmitting coil, and retain the electrical parameters of the coil assembly 11, which needs to make the parameters of the coil assembly different from the parameters of the transmitting coil for causing the electromagnetic induction to occur, such as the above-mentioned two different frequencies. To this end, the present application also comprises a power supply 5, the power supply 5 supplying at least the detection module 2 and each coil set 11.

The power supply to the detection module 2 is to ensure the normal operation of the operation thereof, and the power supply to each coil set 11 is to make the coil set 11 have an electrical parameter different from that generated by electromagnetic induction.

The power source 5 may be an independent power supply unit for supplying power to the detection module 2 and the coil assembly 11, or may be a part of the detection module 2, for example, when the detection module 2 is an independent impedance detector, the power source 5 may be included, and when the impedance detector is mounted to the detection apparatus of the present application, the power source supplies power to the coil assembly 11.

The structure, features and effects of the present invention have been described in detail above according to the embodiment shown in the drawings, and the above description is only the preferred embodiment of the present invention, but the present invention is not limited to the implementation scope shown in the drawings, and all changes made according to the idea of the present invention or equivalent embodiments modified to the same changes should be considered within the protection scope of the present invention when not exceeding the spirit covered by the description and drawings.

Claims

1. A foreign object detection apparatus of a wireless charging system, comprising:

a detection coil set (1) and a detection module (2), wherein,

the detection coil set (1) consists of a plurality of coil groups (11);

the detection module (2) sequentially detects the impedance of each coil group (11);

the coil group (11) is provided with at least two symmetrical coils (110), the coils (110) are formed by winding a conductor, and the winding directions of the two symmetrical coils (110) are opposite.

2. The foreign object detection apparatus of a wireless charging system according to claim 1,

the detection coil sets (1) are at least two and are mutually overlapped;

the uncovered area of the coil group (11) in one of the detection coil sets (1) is in the covered area of the coil group (11) in the other detection coil set (1).

3. The foreign object detection apparatus of a wireless charging system according to claim 1,

still include switch module (3), switch module (3) connect in detect between coil assembly (1) and detection module (2), control every coil group (11) in proper order with detection module (2) UNICOM.

4. The foreign object detection apparatus of a wireless charging system according to claim 3,

the device is characterized by further comprising a filtering module (4), wherein the filtering module (4) is connected between the switch module (3) and the detection module (2).

5. The foreign object detection apparatus of a wireless charging system according to claim 1,

the detection module (2) is an impedance detection circuit.

6. The foreign object detection apparatus of a wireless charging system according to claim 1,

further comprising a power supply (5), said power supply (5) supplying at least said detection module (2) and each of said coil sets (11).

7. A wireless charging system comprising a transmitting coil and a housing, characterized by further comprising the foreign object detection apparatus of the wireless charging system of any one of claims 1 to 6, the foreign object detection apparatus of the wireless charging system being disposed between the transmitting coil and the housing.