A transmitting component and charging component structure for wireless charging of electric vehicles

Abstract

The present invention discloses a transmitting component for wireless charging of an electric vehicle, comprising a non-metallic shell, a transmitting coil, a transmitting magnetic core and a metal shell assembled in sequence from top to bottom. The transmitting magnetic core comprises at least two layers of staggered stacked ferrite layers, and each ferrite layer is spliced ​​by a number of ferrites. The ferrite layer corresponding to the periphery of the transmitting coil is close to the transmitting coil, and the remaining ferrite layers corresponding to the center position of the transmitting coil are indented in sequence and gradually move away from the transmitting coil. The projection of the shape of all the stacked and spliced ​​ferrite layers on the plane corresponds to the shape of the transmitting coil. The present invention also discloses a charging component for wireless charging of an electric vehicle, comprising a transmitting component and a receiving component arranged in parallel, which solves the problem of uneven distribution of the transmitting magnetic field, suppresses magnetic saturation, and improves the efficiency of wireless charging.

Description

Technical Field

[0001] The present invention relates to the field of wireless charging, and in particular to a transmitting component and a charging component structure for wireless charging of an electric vehicle. Background Art

[0002] Wireless charging technology for electric vehicles is becoming increasingly popular. Compared to wired charging, it eliminates the need for power distribution cables, making it more convenient and safer. Wireless charging relies on inductive coupling, exchanging energy between a transmitter and a receiver coil. Therefore, the design of the wireless charging component determines the power and efficiency requirements of the electric vehicle. Due to the inherent structure of existing coils and the arrangement of ferrites, magnetic saturation and uneven magnetic field distribution can hinder the flow of magnetic flux. Furthermore, when there is a certain offset between the transmitter and receiver coils, charging time and efficiency cannot be guaranteed. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a transmitting component for wireless charging of electric vehicles. The optimized staggered stacking distribution of ferrites makes the magnetic field generated by the transmitting coil more uniform.

[0004] A charging component structure for wireless charging of electric vehicles is also provided, which suppresses magnetic saturation and improves wireless charging efficiency.

[0005] The present invention is implemented by the following technical solutions:

[0006] The present invention provides a transmitting component for wireless charging of electric vehicles, comprising a non-metallic shell, a transmitting coil, a transmitting magnetic core and a metal shell assembled in sequence from top to bottom. The transmitting magnetic core comprises at least two layers of staggered ferrite layers, each ferrite layer being composed of a plurality of ferrites spliced ​​together. The ferrite layer corresponding to the periphery of the transmitting coil is close to the transmitting coil, and the remaining ferrite layers are indented in sequence corresponding to the center position of the transmitting coil and gradually move away from the transmitting coil. The projection of the shape of all the stacked and spliced ​​ferrite layers on a plane corresponds to the shape of the transmitting coil.

[0007] The multi-layer stacked structure of ferrite magnetic sheets has ferrites on the four sides that are closer to the coil wound by Litz wire, and the middle ferrite is farther away from the coil wound by Litz wire, which can suppress the generation of magnetic saturation. The stacked design can enhance the magnetic permeability of the ferrite, reduce the power consumption of the ferrite to a certain extent, improve the wireless charging efficiency of the vehicle, and maintain the uniformity of the magnetic field in the space of the transmitting coil, further meeting the interoperability of the wireless charging system.

[0008] Furthermore, the transmitting magnetic core includes three layers of staggered ferrite layers, namely a first ferrite layer corresponding to the periphery of the transmitting coil and arranged close to the transmitting coil, a second ferrite layer indented and stacked relative to the first ferrite layer and arranged away from the transmitting coil, and a third ferrite layer indented relative to the second ferrite layer and arranged corresponding to the center of the transmitting coil.

[0009] Ferrite circulates the magnetic flux generated by the transmitting coil, guiding or directing it through the conductor. The three-layer ferrite structure increases the magnetic coupling between the transmitting and receiving coils, further increasing the mutual inductance between the two coils, thereby improving wireless charging efficiency.

[0010] Furthermore, the ferrite is divided into at least a first type of ferrite and a second type of ferrite. The projection of the first type of ferrite on the horizontal plane corresponds to the four corners and the middle position of the transmitting coil, and the projection of the second type of ferrite on the horizontal plane corresponds to other positions of the transmitting coil and is a square.

[0011] Furthermore, the short side of the first type ferrite is equal to the side length of the second type ferrite, and the long side of the first type ferrite is twice the side length of the second type ferrite.

[0012] The first type of ferrites arranged at the four corners and the middle are large-sized ferrites, and the second type of ferrites arranged at other positions are small-sized ferrites, which improve the uniformity of the spatial magnetic field. The four sides of the small ferrites are equal, and their length is the short side size of the large ferrites. The same two types of ferrites can be used to form a spatial magnetic substrate, thereby minimizing the manufacturing cost.

[0013] Furthermore, a gap is provided in the spliced ​​ferrites, and the gap width of the projection along the long side of the coil is 3-5 times the gap width along the wide side.

[0014] The optimal spacing is set between the spliced ​​ferrites to avoid the problem of increased eddy current loss caused by the ferrites being too close, and to avoid the phenomenon of magnetic leakage caused by the ferrites being too far apart.

[0015] Furthermore, the ferrite is a soft magnetic material with a thickness of 2.5-10 mm.

[0016] It is convenient for mass production. As the thickness of ferrite increases, the advantages of ferrite's non-magnetic saturation and heat dissipation can be increased.

[0017] The present invention also provides a charging component structure for wireless charging of electric vehicles, including a transmitting component and a receiving component arranged in parallel, and the receiving component includes a metal shell, a receiving magnetic core, a receiving coil and a non-metallic shell installed in sequence from top to bottom.

[0018] Furthermore, the transmitting coil or the receiving coil is a hollow spiral structure wound with at least two Litz wires of equal length.

[0019] Furthermore, the number of turns of the litz wire of the transmitting coil or the receiving coil is the same, and the bending radius of the winding is equal. The transition between two adjacent turns of the litz wire is a staggered arc tangential connection structure, and the positions at both ends of the litz wire corresponding to the transition are also staggered arc tangential connection structures.

[0020] The four corners are designed with equal arcs to ensure that the magnetic field strength generated by the transmitting coil at each corner is uniform. The tangent connection structure can improve the spatial magnetic field distribution.

[0021] Furthermore, the Litz wire is composed of twisted enameled wires, with a cooling insulation tube in the middle through which a cooling medium passes, and is covered with nylon wire.

[0022] The structure with built-in cooling tube effectively reduces the AC and DC impedance of the Litz wire itself which increases due to the temperature rise.

[0023] The present invention has the following technical advantages or beneficial effects:

[0024] 1. The ferrite in the transmitting component is set to a multi-layer stacked structure, which suppresses the generation of magnetic saturation, enhances the magnetic permeability of the ferrite, and reduces the power consumption of the ferrite.

[0025] 2. The larger ferrites arranged around the periphery are closer to the coil wound by the Litz wire, and the smaller ferrite in the middle is away from the coil, so that the ferrite structure design is reasonable and compact, maintaining the uniformity of the magnetic field of the transmitting coil 101 in space, and improving the wireless charging efficiency of the vehicle.

[0026] 3. The ferrites are arranged at optimal intervals to avoid increased eddy current loss due to close distances between ferrites or magnetic leakage due to long distances. This also avoids the friction that generates magnetic powder during actual use due to tight-fitting connections between ferrites. Once the magnetic powder falls into the circuit, it may cause a short circuit or even the risk of burning the device.

[0027] 4. The transmitting coil is wound in a structure with at least two groups of equal lengths and curvatures, thereby achieving uniformity of the spatial magnetic field of the transmitting coil, thereby allowing the charging efficiency of the receiving coil to remain unchanged within a certain offset.

[0028] 5. Add two arc tangent connection structures at both ends of the Litz wire to further improve the spatial magnetic field distribution.

[0029] 6. The operating temperature of the coil wound with Litz wire with a cooling tube is about 30 degrees lower than that of the coil without cooling. It can effectively reduce the increase in AC and DC impedance of the Litz wire as the temperature rises, effectively improve the efficiency of the wireless charging system, and extend the service life of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is an exploded view of the electric vehicle wireless charging transmitter assembly according to an embodiment of the present invention.

[0031] Figure 2 This is a schematic diagram of the transmitting magnetic core of the wireless charging transmitting assembly of an electric vehicle according to an embodiment of the present invention.

[0032] Figure 3 This is a front view of the transmitting magnetic core of the wireless charging transmitting assembly of an electric vehicle according to an embodiment of the present invention.

[0033] Figure 4 This is a schematic diagram of the charging assembly structure for wireless charging of an electric vehicle according to an embodiment of the present invention.

[0034] Figure 5 This is an exploded view of the receiving component of the charging component for wireless charging of an electric vehicle according to an embodiment of the present invention.

[0035] Figure 6 This is a schematic diagram of the transmitting coil structure of a charging component for wireless charging of an electric vehicle according to an embodiment of the present invention.

[0036] Figure 7 Schematic diagram of the spatial magnetic field of the transmitting coil of the charging component of the wireless charging of electric vehicles in the prior art.

[0037] Figure 8 This is a schematic diagram of the spatial magnetic field of the transmitting coil of the charging component of the wireless charging of an electric vehicle according to an embodiment of the present invention.

[0038] Figure 9 This is a schematic diagram of the cross-sectional structure of the Litz wire of the charging assembly for wireless charging of an electric vehicle according to an embodiment of the present invention.

[0039] In the figure, 10-transmitting component, 20-receiving component, 101-transmitting coil, 102-transmitting magnetic core, 103-metal shell, 104-non-metal shell, 105-bending position of the transmitting coil, 201-receiving coil, 202-receiving magnetic core, 203-metal shell, 204-non-metal shell, 30-Litz wire, 301-enameled wire, 302-outer nylon wire, 303-cooling tube, 305-first Litz wire, 306-second Litz wire, 307-transition point, 40-ferrite layer, 41-first type ferrite, 42-second type ferrite, 43-first ferrite layer, 44-second ferrite layer, 45-third ferrite layer. DETAILED DESCRIPTION

[0040] In order to facilitate those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. The following is only exemplary and does not limit the scope of protection of the present invention.

[0041] Example 1

[0042] like Figure 1 The figure shows an exploded view of the transmitter assembly of an electric vehicle wireless charging assembly according to an embodiment of the present invention. The transmitter assembly comprises, assembled from top to bottom, a non-metallic housing 104, a transmitting coil 101, a transmitting magnetic core 102, and a metal housing 103. The metal housing is attached to the non-metallic housing to provide structural support, effectively protect against EMI, and enhance the coil's heat dissipation capabilities.

[0043] As a preferred embodiment, Figure 2 As shown, the transmitting core 102 comprises three staggered ferrite layers: a first ferrite layer 43 positioned adjacent to and surrounding the transmitting coil 101; a second ferrite layer 44 positioned inset from and away from the first ferrite layer 43; and a third ferrite layer 45 positioned inset from the second ferrite layer 44 and centered within the transmitting coil. The horizontal projections of the first, second, and third ferrite layers 43, 44, and 45 correspond to the shape of the transmitting coil 101. The ferrite layers at the periphery are closer to the coil wound with Litz wire, while the ferrite layer in the middle is further away from the coil wound with Litz wire 30, thereby preventing magnetic saturation. The three-layered ferrite layer structure effectively guides or directs magnetic flux, increasing magnetic coupling between the transmitting and receiving coils, thereby increasing mutual inductance between the two coils and improving wireless charging efficiency.

[0044] As a further preferred embodiment, Figure 2 and Figure 3 As shown, the third ferrite layer 45 is composed of four first-type ferrites 41 spliced ​​together. The first-type ferrites 41 are arranged at the four corners of the first ferrite layer 43, and the second-type ferrites 42 are arranged at the second ferrite layer 44 and other positions of the first ferrite layer 43. This arrangement can maintain the spatial uniformity of the spatial magnetic field generated by the transmitting coil 101.

[0045] As a further preferred embodiment, Figure 2 and Figure 3 As shown, the short side of the first type ferrite 41 is equal to the side length of the second type ferrite 42, and the long side of the first type ferrite 41 is twice the side length of the second type ferrite 42. By dividing the two types of ferrite in the same way to form a spatial magnetic substrate, the manufacturing cost can be minimized.

[0046] As a further preferred embodiment, Figure 3 As shown, the spliced ​​ferrites are spaced apart. The projected width of the gap 46 along the coil's longitudinal direction is 3-5 times the width of the gap 47 along its width. For example, if the gap 46 along the coil's longitudinal direction is 2.5 mm, the gap along its width can be 0.8 mm or 0.5 mm. Optimized spacing is established between the ferrites to avoid increased eddy current losses caused by close proximity, and to prevent magnetic flux leakage caused by excessive distance between ferrites.

[0047] As a further preferred embodiment, the ferrite is made of soft magnetic material with a thickness of 2.5-10 mm, which facilitates mass production and manufacturing while avoiding magnetic saturation and increasing heat dissipation capacity.

[0048] It should be noted that each ferrite in the ferrite layer of the multi-layer stacked structure is separated from each other and formed as a single part. It should be understood that any number of ferrites can be arranged corresponding to the projection area of ​​the transmitting coil 101, and the specific shape of the combination can be changed based on the specific space and design target values.

[0049] Example 2

[0050] Figure 4 This is a schematic diagram of the charging component structure of the wireless charging of an electric vehicle according to an embodiment of the present invention. It includes the above-mentioned transmitting component 10 and receiving component 20 arranged in parallel, such as Figure 5 As shown, the receiving assembly 20 includes a metal shell 203, a receiving magnetic core 202, a receiving coil 201 and a non-metallic shell 204 which are installed in sequence from top to bottom.

[0051] As a further preferred embodiment, Figure 6 As shown, the transmitting coil 101 or receiving coil 201 comprises a hollow spiral structure wound with at least two equal-length Litz wires 30. Each Litz wire 30 has the same number of turns, and the bending radius of each turn of Litz wire 30 at the bend 105 is the same. The ends of the first Litz wire 305 and the second Litz wire 306 are tangential at the transition 307, and adjacent turns of Litz wire 30 are tangential at the transition 307. The ends of the first Litz wire 305 and the second Litz wire 306 are also staggered to ensure a safe spacing.

[0052] It should be noted that the coils are available in various shapes, including rectangular, hexagonal, circular, and elliptical. The specific shape is determined based on the product's appearance and the system's magnetic field requirements. Litz wires 305 and 306 are connected in parallel, either on a circuit board or elsewhere.

[0053] The outer curvature of the existing transmitting coil is large, and the inner curvature is small. The magnetic field strength generated at the corner of the coil is higher than that at other locations. The magnetic field distribution generated by the existing transmitting coil in space is as follows: Figure 7 The magnetic field distribution generated by the transmitting coil 101 of the wireless charging component of the electric vehicle of the present invention in space is shown as follows. Figure 9 As shown, the magnetic field distribution generated by the transmitting coil 101 of the electric vehicle wireless charging assembly of the present invention is more uniform.

[0054] As a further preferred embodiment, Figure 9 As shown, the cross-section of the Litz wire 30 is circular. Each Litz wire 30 is composed of multiple strands of enameled wire 301 twisted together, with a cooling tube 303 disposed in the middle for passage of a cooling medium. The wire is then covered with a nylon filament 302. A cooling medium such as cooling coal or cold air can pass through the cooling tube 303. It should be noted that the cross-section of the Litz wire 30 can also be rectangular or have other shapes. The enameled wire 301 has a diameter of 0.05 mm and a lay length of 30 mm. Using a thinner enameled wire 301 can also reduce the AC resistance of the transmitting coil 101.

[0055] At the wireless charging operating frequency of 85 kHz, the Litz wire with a cooling tube 303 effectively reduces the AC and DC impedance of the Litz wire 30 itself, which increases with temperature, thereby improving wireless charging efficiency. Furthermore, the cooling tube 303 within the Litz wire 30 is made of soft plastic, offering high-voltage insulation. It also has an insulated and sealed structure, and the cooling medium used is either cooling coal or cold air, preventing the risk of coil short circuits and burns caused by coolant leakage.

[0056] By adopting the above scheme, the transmitting coil and the structure of the transmitting magnet of the transmitting component of the wireless charging of the electric vehicle are improved, the magnetic field distribution of the transmitting coil is made more uniform, the efficiency of the wireless charging of the electric vehicle is improved, and the charging is made more efficient.

[0057] The above embodiments are only intended to help understand the method and core concept of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A transmitting assembly for wireless charging of an electric vehicle, comprising a non-metallic housing (104), a transmitting coil (101), a transmitting magnetic core (102), and a metal housing (103) assembled in sequence from top to bottom, characterized in that: The transmitting magnetic core (102) comprises at least two layers of staggered ferrite layers, each ferrite layer being formed by splicing a plurality of ferrites, wherein the ferrite layer corresponding to the periphery of the transmitting coil is close to the transmitting coil, and the remaining ferrite layers corresponding to the center position of the transmitting coil (101) are sequentially indented and gradually away from the transmitting coil (101), and the projection of the shape of all the stacked and spliced ​​ferrite layers on a plane corresponds to the shape of the transmitting coil (101); The transmitting magnetic core (102) comprises three layers of staggered ferrite layers, namely a first ferrite layer (43) arranged corresponding to the periphery of the transmitting coil (101) and close to the transmitting coil (101), a second ferrite layer (44) stacked and indented relative to the first ferrite layer (43) and arranged away from the transmitting coil (101), and a third ferrite layer (45) indented relative to the second ferrite layer (44) and arranged corresponding to the center of the transmitting coil; The ferrite is divided into at least a first type of ferrite (41) and a second type of ferrite (42), wherein the projection of the first type of ferrite (41) on the horizontal plane corresponds to the four corners and the middle position of the transmitting coil, and the projection of the second type of ferrite (42) on the horizontal plane corresponds to other positions of the transmitting coil and is a square; The first type of ferrite is arranged at the four corners of the first ferrite layer, and the second type of ferrite is arranged at other positions; The second ferrite layer is provided with a second type of ferrite; The third ferrite layer is composed of four first-type ferrites spliced ​​together; The short side of the first type ferrite (41) is equal to the side length of the second type ferrite (42), and the long side of the first type ferrite (41) is twice the side length of the second type ferrite (42).

2. The launch assembly according to claim 1, characterized in that: A gap is provided between the spliced ​​ferrites, and the projection width of the gap along the length direction of the coil is 3-5 times the projection width along the width direction.

3. The launch assembly according to claim 1 or 2, characterized in that: The ferrite is a soft magnetic material with a thickness of 2.0-10 mm.

4. A charging assembly structure for wireless charging of electric vehicles, characterized in that: The invention comprises a transmitting component (10) and a receiving component (20) as described in any one of claims 1 to 3, which are arranged in parallel. The receiving component (20) comprises a metal shell (203), a receiving magnetic core (202), a receiving coil (201) and a non-metallic shell (204) which are installed in sequence from top to bottom.

5. The charging assembly structure according to claim 4, characterized in that: The transmitting coil (101) and / or receiving coil (201) is a hollow spiral structure wound with at least two Litz wires (30) of equal length.

6. The charging assembly structure according to claim 5, characterized in that: The number of turns of the Litz wire (30) wound around the transmitting coil (101) and / or the receiving coil (201) is the same, and the bending radius of the winding is equal; the transition points (307) between two adjacent turns of the Litz wire (30) are mutually staggered arc tangent connection structures, and the positions at both ends of the Litz wire (30) corresponding to the transition points (307) are mutually staggered arc tangent connection structures.

7. The charging assembly structure according to claim 5 or 6, characterized in that: The Litz wire (30) is composed of twisted enameled wires (301), with a cooling pipe (303) through which a cooling medium passes, and is covered with nylon wire (302).

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