KR102280255B1 - Wireless charging pad, wireless charging device, and electric vehicle comprising same - Google Patents

Abstract

The wireless charging pad according to one embodiment can easily discharge heat through the refrigerant by disposing the micro-channel inside or adjacent to the magnetic material. Accordingly, the wireless charging pad and the wireless charging device employing the structure thereof may be usefully used in electric vehicles that require large-capacity power transmission between a transmitter and a receiver.

Description

Wireless charging pad, wireless charging device, and electric vehicle including the same {WIRELESS CHARGING PAD, WIRELESS CHARGING DEVICE, AND ELECTRIC VEHICLE COMPRISING SAME}

Embodiments relate to a wireless charging pad, a wireless charging device, and an electric vehicle including the same. More specifically, the embodiment relates to a wireless charging pad with improved charging efficiency by applying a heat dissipation structure, a wireless charging device, and an electric vehicle including the same.

Today, the information and communication field is developing at a very fast pace, and various technologies that comprehensively combine electricity, electronics, communication, and semiconductor are continuously being developed. In addition, as electronic devices become more mobile, research on wireless communication and wireless power transmission technology is actively conducted in the communication field. In particular, research on a method of wirelessly transmitting power to an electronic device or the like is being actively conducted.

The wireless power transmission wirelessly transmits power through space using an electromagnetic field resonance structure such as magnetic coupling, capacitive coupling, or an antenna without physical contact between a transmitter that supplies power and a receiver that receives power. will be sent to The wireless power transmission is suitable for portable communication devices and electric vehicles that require a large-capacity battery, and since the contacts are not exposed, there is little risk of a short circuit, and a wired charging failure phenomenon can be prevented.

Meanwhile, as interest in electric vehicles has rapidly increased in recent years, interest in building charging infrastructure is increasing. Various charging methods such as electric vehicle charging using home chargers, battery replacement, fast charging devices, and wireless charging devices have already appeared, and new charging business models have also begun to appear (refer to Korean Patent Application Laid-Open No. 2011-0042403). In addition, electric vehicles and charging stations that are being tested in Europe are starting to stand out, and in Japan, car manufacturers and electric power companies are piloting electric vehicles and charging stations.

Korean Patent Publication No. 2011-0042403

In the conventional wireless charging pad used in electric vehicles, etc., with reference to FIG. 4 , a magnetic material 300 ′ is disposed adjacent to the coil 200 ′ to improve wireless charging efficiency, and a shield unit 400 ′ for shielding ) is disposed to be spaced apart from the magnetic material 300 ′ by a predetermined interval.

The wireless charging pad generates heat during the wireless charging operation due to the resistance of the coil and the magnetic loss of the magnetic material. In particular, the magnetic material in the wireless charging pad generates heat in the vicinity of the coil with high electromagnetic wave energy density, and the generated heat changes the magnetic properties of the magnetic material, causing impedance mismatch between the transmitting pad and the receiving pad, and lowering the charging efficiency. There was a problem in that the heat further worsened due to this. However, since such a wireless charging pad is installed in the lower part of the electric vehicle, it is difficult to implement a heat dissipation structure because it adopts a sealed structure for dustproof, waterproof and shock absorption.

As a result of research by the present inventors, it was found that heat can be easily discharged through the refrigerant by arranging a microchannel inside or adjacent to the magnetic material used in the wireless charging pad.

Accordingly, an object of the embodiment is to provide a wireless charging pad with improved heat dissipation, a wireless charging device, and an electric vehicle including the same.

According to one embodiment, a coil comprising a conductive wire; a shield portion disposed on the coil; a magnetic material disposed between the coil and the shield unit; and a microchannel disposed inside or adjacent to the magnetic material, a wireless charging pad is provided.

According to another embodiment, the housing; a coil disposed within the housing and including a conductive wire; a shield portion disposed on the coil; a magnetic material disposed between the coil and the shield unit; a microchannel disposed inside or adjacent to the magnetic material; and a cooler disposed outside the housing and connected to the microchannel, a wireless charging device is provided.

According to another embodiment, there is provided an electric vehicle including a wireless charging device, the wireless charging device comprising: a housing; a coil disposed within the housing and including a conductive wire; a shield portion disposed on the coil; a magnetic material disposed between the coil and the shield unit; a microchannel disposed inside or adjacent to the magnetic material; and a cooler disposed outside the housing and connected to the microchannel.

According to the embodiment, heat can be easily discharged through the refrigerant by disposing the micro-channel inside or adjacent to the magnetic material used for the wireless charging pad.

According to a specific embodiment, by forming a micro-channel inside the magnetic material used for the wireless charging pad and circulating a gaseous or liquid fluid as a refrigerant in connection with an external cooler, heat generated from the magnetic material is transferred to the outside. can be released easily.

Accordingly, the wireless charging pad and the wireless charging device employing the structure thereof may be usefully used in electric vehicles that require large-capacity power transmission between a transmitter and a receiver.

1 shows a configuration diagram of a wireless charging pad according to an embodiment.
2A is a plan view of a magnetic material including a microchannel therein.
Figure 2b shows a process of forming a magnetic material through a mold.
3A and 3B are cross-sectional views of a wireless charging device according to an embodiment.
4 is a diagram showing the configuration of a conventional wireless charging pad.
5 shows an application example of a wireless charging device according to an embodiment.
6 shows an electric vehicle to which a wireless charging device is applied as a receiver.

In the description of the embodiments below, one component is described as being formed above or below another component, one component is directly above or below another component, or indirectly through another component including all that are formed by

In addition, the reference for the upper / lower of each component will be described with reference to the drawings. The size of each component in the drawings may be exaggerated for explanation, and may be different from the size actually applied.

In the present specification, "including" a certain component does not exclude other components, unless otherwise stated, means that other components may be further included.

In addition, it should be understood that all numerical ranges indicating characteristic values, dimensions, etc. of components described in this specification are modified by the term "about" in all cases unless otherwise specified.

In the present specification, unless otherwise specified, the expression "a" or "a" is interpreted as meaning including the singular or the plural as interpreted in context.

[Wireless Charging Pad]

1 shows a configuration diagram of a wireless charging pad according to an embodiment.

Referring to FIG. 1 , the wireless charging pad 10 according to an embodiment includes a coil 200 including a conductive wire; a shield unit 400 disposed on the coil 200; a magnetic material 300 disposed between the coil 200 and the shield unit 400; and a microchannel 500 disposed inside or adjacent to the magnetic material 300 .

Hereinafter, each component of the wireless charging pad will be described in detail.

support plate

The wireless charging pad 10 may further include a support plate 100 for supporting the coil 200 . The material and structure of the support plate may employ the material and structure of a conventional support plate used for a wireless charging pad. The support plate may have a flat plate structure or a structure in which a groove is dug along a coil shape to fix the coil.

coil

The coil includes a conductive wire.

The conductive wire includes a conductive material. For example, the conductive wire may include a conductive metal. Specifically, the conductive wire may include at least one metal selected from the group consisting of copper, nickel, gold, silver, zinc, and tin.

In addition, the conductive wire may have an insulating sheath. For example, the insulating shell may include an insulating polymer resin. Specifically, the insulating shell may include a polyvinyl chloride (PVC) resin, a polyethylene (PE) resin, a Teflon resin, a silicone resin, a polyurethane resin, and the like.

The diameter of the conductive wire may be, for example, in the range of 1 mm to 10 mm, in the range of 1 mm to 5 mm, or in the range of 1 mm to 3 mm.

The conductive wire may be wound in the form of a flat coil. Specifically, the planar coil may include a planar spiral coil. In addition, the planar shape of the coil may be an elliptical shape, a polygonal shape, or a polygonal shape with rounded corners, but is not particularly limited.

The outer diameter of the planar coil may be 5 cm to 100 cm, 10 cm to 50 cm, 10 cm to 30 cm, 20 cm to 80 cm, or 50 cm to 100 cm. As a specific example, the planar coil may have an outer diameter of 10 cm to 50 cm.

In addition, the inner diameter of the planar coil may be 0.5 cm to 30 cm, 1 cm to 20 cm, or 2 cm to 15 cm.

The number of windings of the flat coil may be 5 to 50 times, 10 to 30 times, 5 to 30 times, 15 to 50 times, or 20 to 50 times. As a specific example, the flat coil may be formed by winding the conductive wire 10 to 30 times.

In addition, the distance between the conductive wires in the planar coil shape may be 0.1 cm to 1 cm, 0.1 cm to 0.5 cm, or 0.5 cm to 1 cm.

When within the preferred planar coil dimensions and specifications as described above, it may be suitable for fields requiring large-capacity power transmission, such as electric vehicles.

shield part

The shield part is disposed on the coil.

The shield unit suppresses electromagnetic interference (EMI) that may be generated by leakage of electromagnetic waves to the outside through electromagnetic shielding.

The shield part may be disposed to be spaced apart from the coil by a predetermined interval. For example, a distance between the shield and the coil may be 10 mm or more or 15 mm or more, and specifically, 10 mm to 30 mm, or 10 mm to 20 mm.

The material of the shield part may be, for example, a metal, and thus the shield part may be a metal plate, but is not particularly limited. As a specific example, the material of the shield part may be aluminum, and other metal or alloy materials having electromagnetic wave shielding ability may be used.

The thickness of the shield part may be 0.2 mm to 10 mm, 0.5 mm to 5 mm, or 1 mm to 3 mm. In addition, the area of the shield part may be 200 cm ² or more, 400 cm ² or more, or 600 cm ² or more.

magnetic material

The magnetic material is disposed between the coil and the shield unit.

The magnetic material may be disposed to be spaced apart from the shield part by a predetermined interval. For example, the separation distance between the magnetic material and the shield portion may be 3 mm or more, 5 mm or more, 3 mm to 10 mm, or 4 mm to 7 mm.

In addition, the magnetic material may be disposed to be spaced apart from the coil by a predetermined interval. For example, the separation distance between the magnetic material and the coil may be 0.2 mm or more, 0.5 mm or more, 0.2 mm to 3 mm, or 0.5 mm to 1.5 mm.

The magnetic material may be a polymer-type magnetic material including a binder resin and magnetic powder.

Alternatively, the magnetic material may include a metallic magnetic material, for example, a nanocrystalline magnetic material.

Alternatively, the magnetic material may be a composite material of the polymer-type magnetic material and the nanocrystalline magnetic material.

high molecular weight material

The magnetic material may include a binder resin and magnetic powder dispersed in the binder resin.

Accordingly, in the polymer-type magnetic material, magnetic powders are combined with each other by a binder resin, so that overall defects are small over a large area and damage due to impact can be small.

The magnetic powder may include oxide magnetic powder such as ferrite (Ni-Zn-based, Mg-Zn-based, Mn-Zn-based ferrite, etc.); metallic magnetic powders such as permalloy, sandust, and nanocrystalline magnetic material; Or it may be a mixed powder thereof. More specifically, the magnetic powder may be sandus particles having a Fe-Si-Al alloy composition.

As an example, the magnetic powder may have a composition of Formula 1 below.

[Formula 1]

Fe _1-abc Si _a X _b Y _c

wherein X is Al, Cr, Ni, Cu, or a combination thereof; Y is Mn, B, Co, Mo, or a combination thereof; 0.01 ≤ a ≤ 0.2, 0.01 ≤ b ≤ 0.1, and 0 ≤ c ≤ 0.05.

The average particle diameter of the magnetic powder may be in the range of about 3 nm to about 1 mm, about 1 μm to 300 μm, about 1 μm to 50 μm, or about 1 μm to 10 μm.

The polymer type magnetic material may include the magnetic powder in an amount of 50 wt% or more, 70 wt% or more, or 85 wt% or more.

For example, the polymeric magnetic material may contain 50 wt% to 99 wt%, 70 wt% to 95 wt%, 70 wt% to 90 wt%, 75 wt% to 90 wt%, 75 wt% to the magnetic powder. 95% by weight, 80% to 95% by weight, or 80% to 90% by weight.

The binder resin may be a curable resin. Specifically, the binder resin may include a photocurable resin, a thermosetting resin, and/or a high heat-resistant thermoplastic resin, preferably a thermosetting resin.

As a resin capable of exhibiting adhesiveness by being cured in this way, it includes at least one functional group or site that can be cured by heat, such as a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group, or an amide group; or at least one functional group or moiety that can be cured by active energy such as an epoxide group, a cyclic ether group, a sulfide group, an acetal group, or a lactone group resin can be used. Such a functional group or moiety may be, for example, an isocyanate group (-NCO), a hydroxyl group (-OH), or a carboxyl group (-COOH).

Specifically, the curable resin may be exemplified by a polyurethane resin, an acrylic resin, a polyester resin, an isocyanate resin, or an epoxy resin having at least one functional group or site as described above, but is not limited thereto.

As an example, the binder resin may include a polyurethane-based resin, an isocyanate-based curing agent, and an epoxy-based resin.

The polymeric magnetic material may contain the binder resin in an amount of 5 wt% to 40 wt%, 5 wt% to 20 wt%, 5 wt% to 15 wt%, or 7 wt% to 15 wt%.

In addition, based on the weight of the polymeric magnetic material, as the binder resin, 6 wt% to 12 wt% of a polyurethane-based resin, 0.5 wt% to 2 wt% of a isocyanate-based curing agent, and 0.3 wt% to 1.5 wt% It may contain an epoxy-based resin of weight %.

The polymer-type magnetic material can be prepared by a sheet-forming process such as mixing magnetic powder and a polymer resin composition to slurry it, then molding it into a sheet shape and curing it, but a large-area polymer-type magnetic material having a constant thickness is manufactured In order to do this, the block can be manufactured by molding using a mold.

The molding may be performed by injecting a raw material of a magnetic material into a mold by injection molding. More specifically, the magnetic material is obtained by mixing a magnetic powder and a polymer resin composition to obtain a raw material composition, and then injecting the raw material composition 301 into the mold 3 by the injection molding machine 2 as shown in FIG. 2b. can be manufactured. At this time, by designing the internal shape of the mold 3 as a three-dimensional structure, the three-dimensional structure of the magnetic material can be easily implemented. Such a process is impossible when using a conventional sintered ferrite sheet as a magnetic material.

Nanocrystalline magnetic material

The magnetic material may include a nanocrystalline magnetic material. When the nanocrystalline magnetic material is applied, the higher the distance from the coil, the lower the resistance (Rs) even if the inductance (Ls) of the coil is lowered, so that the quality factor (Q factor: Ls/Rs) of the coil is increased. Charging efficiency may be improved and heat generation may be reduced.

For example, the nanocrystalline magnetic material may be a Fe-based nanocrystalline magnetic material, specifically, a Fe-Si-Al-based nanocrystalline magnetic material, a Fe-Si-Cr-based nanocrystalline magnetic material, or Fe It may be a -Si-B-Cu-Nb-based nanocrystalline magnetic material.

More specifically, the nanocrystalline magnetic material may be a Fe-Si-B-Cu-Nb-based nanocrystalline magnetic material, in this case, Fe is 70 element% to 85 element%, and the sum of Si and B is 10 It is preferable that element % to 29 element %, and the sum of Cu and Nb is from 1 element % to 5 element % (here, element % means a percentage of the number of specific elements with respect to the total number of elements constituting the magnetic material). In the above composition range, the Fe-Si-B-Cu-Nb-based alloy can be easily formed into a nanocrystalline magnetic material by heat treatment.

The nanocrystalline magnetic material is manufactured by, for example, a Fe-based alloy by a rapid cooling and solidification method (RSP) by melt spinning, and is free of magnetism for 30 minutes to 2 hours at a temperature range of 300° C. to 700° C. to obtain a desired magnetic permeability. It can be prepared by performing an enteric heat treatment.

If the heat treatment temperature is less than 300 ℃, nanocrystals are not sufficiently formed, so the desired magnetic permeability is not obtained, and the heat treatment time may take a long time. In addition, if the heat treatment temperature is low, the treatment time is long, and conversely, if the heat treatment temperature is high, the treatment time is preferably shortened.

The nanocrystalline magnetic material is difficult to make thick in the manufacturing process, and may be formed to a thickness of, for example, 15 μm to 35 μm.

Area and thickness of magnetic material

The magnetic material may be a magnetic sheet, a magnetic sheet laminate, or a magnetic block.

The magnetic material may have a large area, specifically 200 cm ² or more, 400 cm ² or more, or 600 cm ² or more. In addition, the magnetic material may have an area of ^{10,000 cm 2 or less.}

The large-area magnetic material may be configured by combining a plurality of unit magnetic materials, and in this case, the area of the unit magnetic material may be 60 cm ² or more, 90 cm ² , or 95 cm ² to 900 cm ² .

The thickness of the magnetic sheet may be 15 μm or more, 50 μm or more, 80 μm or more, 15 μm to 150 μm, 15 μm to 35 μm, or 85 μm to 150 μm. Such a magnetic sheet may be manufactured by a method for manufacturing a conventional film or sheet.

The magnetic sheet laminate may be one in which 20 or more magnetic sheets or 50 or more magnetic sheets are laminated. In addition, the laminate of the magnetic sheet may be a stack of 150 or less or 100 or less of the magnetic sheet.

The thickness of the magnetic block may be 1 mm or more, 2 mm or more, 3 mm or more, or 4 mm or more. In addition, the thickness of the magnetic block may be 6 mm or less.

Magnetic properties of magnetic materials

The magnetic material may have a certain level of magnetic properties in the vicinity of a standard frequency for wireless charging of an electric vehicle.

The wireless charging standard frequency of the electric vehicle may be less than 100 kHz, for example, 79 kHz to 90 kHz, specifically 81 kHz to 90 kHz, more specifically about 85 kHz, which is a mobile electronic device such as a mobile phone. It is a band distinct from the applied frequency.

The magnetic permeability in the frequency band of 79 kHz to 90 kHz of the magnetic material may vary depending on the material, and may be in the range of 5 to 150,000, and may be in the range of 5 to 300, 500 to 3,500, or 10,000 to 150,000, depending on the specific material. . In addition, the investment loss in the frequency band of 79 kHz to 90 kHz of the magnetic material may vary depending on the material, and may be 0 to 50,000 in a wide range, 0 to 1,000, 1 to 100, 100 to 1,000, or It may be 5,000 to 50,000.

As a specific example, when the magnetic material is a polymer-type magnetic block including a magnetic powder and a binder resin, the magnetic permeability in the frequency band of 79 kHz to 90 kHz may be 5 to 130, 15 to 80, or 10 to 50, The investment loss can be 0 to 20, 0 to 15, or 0 to 5.

Characteristics of magnetic materials

The polymer type magnetic material may be elongated at a certain ratio. For example, the elongation of the polymer type magnetic material may be 0.5% or more. The elongation property is difficult to obtain in a ceramic-based magnetic material that does not apply a polymer, and can reduce damage even when a large-area magnetic material is distorted due to an impact. Specifically, the elongation of the polymer type magnetic material may be 0.5% or more, 1% or more, or 2.5% or more. There is no particular limitation on the upper limit of the elongation, but if the content of the polymer resin is increased to improve the elongation, properties such as inductance of the magnetic material may be deteriorated, so that the elongation is preferably 10% or less.

The magnetic material has a small rate of change in properties before and after impact, and is significantly superior to that of a general ferrite magnetic sheet. In the present specification, the characteristic change rate (%) before and after the impact of a certain characteristic may be calculated by the following formula. Characteristic change rate (%) = | Property Values Before Impact - Property Values After Impact | / pre-impact property value x 100

For example, the magnetic material may have an inductance change rate of less than 5% or less than 3% before and after an impact applied by free-falling from a height of 1 m. More specifically, the inductance change rate may be 0% to 3%, 0.001% to 2%, or 0.01% to 1.5%. When within the above range, the inductance change rate before and after the impact is relatively small, so the stability of the magnetic material may be further improved.

In addition, the magnetic material may have a quality factor (Q factor) change rate of 0% to 5%, 0.001% to 4%, or 0.01% to 2.5% before and after the impact applied by free falling from a height of 1 m. When within the above range, the change in properties before and after impact is small, so the stability and impact resistance of the magnetic material can be further improved.

In addition, the magnetic material may have a resistance change rate of 0% to 2.8%, 0.001% to 1.8%, or 0.1% to 1.0% before and after an impact applied by free falling from a height of 1 m. When it is within the above range, the resistance value may be well maintained below a certain level even if it is repeatedly applied in an environment to which an actual shock and vibration are applied.

In addition, the magnetic material may have a rate of change in charging efficiency before and after an impact applied by free falling from a height of 1 m to 0% to 6.8%, 0.001% to 5.8%, or 0.01% to 3.4%. When it is within the above range, the properties of the magnetic material of a large area may be more stably maintained even if an impact or distortion occurs repeatedly.

micro euro

The wireless charging pad according to the embodiment includes a microchannel disposed inside or adjacent to the magnetic material. Accordingly, heat generated from the magnetic material can be effectively discharged to the outside.

The shape of the microchannel is not particularly limited as long as it is a shape for easily transferring heat of the magnetic material to the outside by a fluid. 2A is a plan view of a magnetic material including a microchannel therein. As shown in FIG. 2A , the microchannel 500 may be designed so that the fluid injected into the inlet 510 circulates over a large area and then exits through the outlet 520 .

Meanwhile, since a region in the magnetic material where heat is mainly generated is a region corresponding to a coil, the microchannel may be disposed to correspond to a region in which the coil is present. In other words, the microchannel may hardly be disposed in the central portion where the density of the conductive wire is low in the coil.

The microchannel may have an inner diameter of 0.1 mm to 5 mm. When within the above range, while maintaining the magnetic properties per volume of the magnetic material, it is possible to further increase the heat dissipation properties through the smooth flow of the fluid. More specifically, the microchannel may have an inner diameter of 0.5 mm to 3 mm, 0.5 mm to 2 mm, or 2 mm to 5 mm.

1 and 3A , the microchannel 500 may be disposed inside the magnetic material 300 . In this case, there is an advantage in that heat generated inside the magnetic material can be effectively treated. A structure in which the microchannel is disposed inside the magnetic material may be designed in various ways.

As an example, the polymer-type magnetic material may be molded through a mold to have a micro-channel therein. In this case, the microchannel may be defined as an internal empty space of the magnetic material.

As another example, the micro-channel may be inserted after molding the polymer-type magnetic material through a mold to have an internal space into which the micro-channel is to be inserted. In this case, the microchannel may be pre-fabricated with a metal or other thermally conductive material and then inserted into the polymer-type magnetic material.

As another example, by inserting and stacking microchannels between a plurality of magnetic sheets, a magnetic sheet laminate having microchannels inserted therein may be manufactured.

The microchannel may have a total internal volume of 5% to 70% based on the total volume of the magnetic material. When within the above range, it may be more advantageous to simultaneously improve the electromagnetic wave shielding performance and heat dissipation characteristics of the magnetic material. More specifically, the microchannel may have a total internal volume of 5% to 40%, 20% to 50%, or 40% to 70% based on the total volume of the magnetic material.

Alternatively, as shown in FIG. 3B , the microchannel 500 may be disposed adjacent to the magnetic material 300 . As an example, the microchannel 500 may be disposed between the magnetic material 300 and the shield unit 400 . As another example, the microchannel 500 may be disposed between the magnetic material 300 and the coil 200 . In this case, there is an advantage in that heat generated from the magnetic material and the coil can be simultaneously processed.

Meanwhile, as shown in FIG. 3B , the microchannel 500 may be formed inside the heat sink 700 , and the heat sink 700 may be disposed adjacent to the magnetic material 300 . For example, the heat sink 700 may be attached to one surface of the magnetic material 300 . Specifically, the heat sink 700 may be attached to one surface of the magnetic material 300 facing the shield unit 400 .

The heat sink may be made of a thermally conductive material. The thermally conductive material may include a metal-based, carbon-based, or ceramic-based material. In addition, the thermally conductive material may be a composite material in which a metal-based, carbon-based, ceramic-based material is dispersed in a binder resin.

[Wireless Charging Device]

3A and 3B are cross-sectional views of a wireless charging device according to an embodiment.

3A and 3B, the wireless charging device 11 according to an embodiment includes a housing 600; a coil 200 disposed within the housing 600 and including a conductive wire; a shield unit 400 disposed on the coil 200; a magnetic material 300 disposed between the coil 200 and the shield unit 400; a microchannel 500 disposed inside or adjacent to the magnetic material 300; and a cooler 15 disposed outside the housing 600 and connected to the microchannel 500 .

The housing allows components such as the coil, the shield unit, and the magnetic material to be properly arranged and assembled. The material and structure of the housing may adopt the material and structure of a typical housing used in a wireless charging device.

The wireless charging device according to the embodiment may further include a support plate for supporting the coil.

The configuration and characteristics of the support plate, the coil, the shield part, and the magnetic material of the wireless charging device are as described above.

The wireless charging device may further include a fluid for cooling that circulates through the microchannel and the cooler. The fluid may transfer heat generated from the magnetic material to the outside. Specifically, the fluid may transfer heat generated from the magnetic material to the cooler.

The fluid may be gas or liquid, for example, air, water, or other liquid or gaseous fluid used as a refrigerant.

Specifically, the fluid may be air, water, oil (eg, engine oil), alcohol (eg, ethylene glycol, propylene glycol, antifreeze), or a mixture thereof.

The thermal conductivity of the fluid may be 0.022 W/m·K to 0.69 W/m·K at 20° C., for example, 0.022 W/m·K to 0.038 W/m·K, 0.57 W/m·K to 0.69 W/m·K, 0.13 W/m·K to 0.15 W/m·K, or 0.24 W/m·K to 0.69 W/m·K.

The density of the fluid may be 0.75 kg/m ³ to 1100 kg/m ³ at 20° C., for example, 0.75 kg/m ³ to 1.39 kg/m ³ , 840 kg/m ³ to 1000 kg/m ³ , 800 kg/m ³ to 900 kg/m ³ , or 840 kg/m ³ to 1100 kg/m ³ .

The heat capacity of the fluid may be 1005 J/kg·K to 4250 J/kg·K at 20° C., for example, 1005 J/kg·K to 1023 J/kg·K, 4150 J/kg·K to 4250 J/kg·K, 1700 J/kg·K to 2500 J/kg·K, or 2500 J/kg·K to 4250 J/kg·K.

The thermal diffusivity of the fluid may be 6×10 ⁻⁸ m ² /s to 4960×10 ⁻⁸ m ² /s at 20° C., for example, 1570×10 ⁻⁸ m ² /s to 4960×10 ⁻⁸ m ² /s, 10×10 ^-8 m ² /s to 20×10 ^-8 m ² /s, 6×10 ^-8 m ² /s to 10×10 ^-8 m ² /s, or 9×10 ^{- It may be from 8} m ² /s to 20×10 ^-8 m ² /s.

According to one embodiment, the fluid has a thermal conductivity of 0.022 W/m·K to 0.038 W/m·K at 1 atm and 20° C., ^{a density of 0.75 kg/m 3} to 1.39 kg/m ³ , 1005 J/kg ·K to 1023 J/kg·K of heat capacity, 1570×10 ^-8 m ² /s to 4960×10 ^-8 m ² /s It may have a thermal diffusivity.

According to another embodiment, the fluid has a thermal conductivity of 0.57 W/m·K to 0.69 W/m·K at 20° C., ^{a density of 840 kg/m 3} to 1000 kg/m ³ , 4150 J/kg·K to A heat capacity of 4250 J/kg·K, 10×10 ⁻⁸ m ² /s to 20×10 ⁻⁸ m ² /s may have a thermal diffusivity.

According to another embodiment, the fluid has a thermal conductivity of 0.13 W/m·K to 0.15 W/m·K at 20° C., ^{a density of 800 kg/m 3} to 900 kg/m ³ , 1700 J/kg·K to 2500 J/kg·K of heat capacity, 6×10 ⁻⁸ m ² /s to 10×10 ⁻⁸ m ² /s It may have a thermal diffusivity.

According to another embodiment, the fluid has a thermal conductivity of 0.24 W/m·K to 0.69 W/m·K at 20° C., ^{a density of 840 kg/m 3} to 1100 kg/m ³ , 2500 J/kg·K to 4250 J/kg·K of heat capacity, 9×10 ⁻⁸ m ² /s to 20×10 ⁻⁸ m ² /s It may have a thermal diffusivity.

The cooler may adopt a method and structure for effectively cooling the fluid. For example, the cooler may cool the fluid by air cooling or water cooling.

The cooler may be connected to the microchannel while having a sealed structure for waterproofing and dustproofing. As shown in FIGS. 3A and 3B , it may be connected to the cooler 15 through a connection passage 16 at the inlet and outlet of the micro-channel 500 .

In addition, the wireless charging device may further include a device for generating a flow of fluid in the microchannel, for example, a circulation pump.

In addition, the wireless charging device may further include a spacer for securing a space between the shield unit and the magnetic material. The material and structure of the spacer may adopt the material and structure of a typical housing used in a wireless charging device.

The wireless charging device can easily dissipate heat through the refrigerant by disposing a micro-channel in or adjacent to the magnetic material. Accordingly, the wireless charging device may be usefully used in an electric vehicle requiring large-capacity power transmission between a transmitter and a receiver.

[Electric Vehicle]

5 shows a wireless charging device applied to an electric vehicle.

The wireless charging device 11 may be provided under the electric vehicle 1 .

An electric vehicle according to an embodiment includes a wireless charging device, wherein the wireless charging device includes: a housing; a coil disposed within the housing and including a conductive wire; a shield portion disposed on the coil; a magnetic material disposed between the coil and the shield unit; a microchannel disposed inside or adjacent to the magnetic material; and a cooler disposed outside the housing and connected to the microchannel.

The configuration and characteristics of each component of the wireless charging device included in the electric vehicle are as described above.

As a cooler of the wireless charging device, a cooling facility basically provided in the electric vehicle may be used.

For example, the cooler may include an automobile air conditioner. Specifically, as shown in FIG. 5 , the air conditioner provided in the interior of the electric vehicle 1 is used as the cooler 15 , and the connection passage 16 connected to the inlet and outlet of the microchannel of the wireless charging device 11 and The air conditioner may be connected. Accordingly, even without manufacturing a separate cooler, effective heat dissipation may be possible.

The electric vehicle may further include a battery receiving power from the wireless charging device. The wireless charging device may receive power wirelessly and transmit it to the battery, and the battery may supply power to a driving system of the electric vehicle. The battery may be charged by power transmitted from the wireless charging device or other additional wired charging devices.

In addition, the electric vehicle may further include a signal transmitter for transmitting information about charging to the transmitter of the wireless charging system for the electric vehicle. The information about such charging may be charging efficiency such as charging speed, charging degree, and the like.

The wireless charging device may be provided under the vehicle.

6 shows an electric vehicle to which a wireless charging device is applied.

The electric vehicle may be charged wirelessly in a parking area equipped with a wireless charging system for an electric vehicle.

Referring to FIG. 6 , the electric vehicle 1 according to an embodiment includes the wireless charging device according to the embodiment as a receiver 21 . The wireless charging device may serve as a receiver 21 for wireless charging of the electric vehicle 1 and receive power from a transmitter 22 for wireless charging.

1: electric vehicle,
2: injection molding machine, 3: mold,
10, 10': wireless charging pad, 11: wireless charging device,
15: cooler, 16: connection flow path,
21: receiver, 22: transmitter,
100, 100': support plate, 200, 200': coil,
300, 300': magnetic material, 301: raw material composition,
400, 400': shield unit, 500: micro flow path,
510: inlet, 520: outlet;
600: housing, 700: heat sink.

Claims (14)

a coil comprising a conductive wire;
a shield portion disposed on the coil;
a magnetic material disposed between the coil and the shield unit; and
Containing a micro-channel disposed inside the magnetic material,
wireless charging pad.
delete The method of claim 1,
The microchannel has a total internal volume of 5% to 70% based on the total volume of the magnetic material, wireless charging pad.
The method of claim 1,
The microchannel has an inner diameter of 0.1 mm to 5 mm, wireless charging pad.
a coil comprising a conductive wire;
a shield portion disposed on the coil;
a magnetic material disposed between the coil and the shield unit; and
Including a microchannel disposed inside or adjacent to the magnetic material,
The micro-channel is disposed corresponding to the area in which the coil exists, a wireless charging pad.
The method of claim 1,
The wireless charging pad, wherein the magnetic material comprises a binder resin and magnetic powder dispersed in the binder resin.
The method of claim 1,
The magnetic material includes a nanocrystalline (nanocrystalline) magnetic material, wireless charging pad.
housing;
a coil disposed within the housing and including a conductive wire;
a shield portion disposed on the coil;
a magnetic material disposed between the coil and the shield unit;
a microchannel disposed inside the magnetic material; and
including a cooler disposed outside the housing and connected to the microchannel,
wireless charging device.
9. The method of claim 8,
The wireless charging device, the wireless charging device further comprising a fluid for cooling that circulates through the micro-channel and the cooler.
10. The method of claim 9,
The fluid transfers heat generated from the magnetic material to the cooler, a wireless charging device.
10. The method of claim 9,
The fluid has a thermal conductivity of 0.022 W / m · K to 0.69 W / m · K, wireless charging device.
10. The method of claim 9,
The cooler cools the fluid by air cooling or water cooling, a wireless charging device.
As an electric vehicle including a wireless charging device,
The wireless charging device
housing;
a coil disposed within the housing and including a conductive wire;
a shield portion disposed on the coil;
a magnetic material disposed between the coil and the shield unit;
a microchannel disposed inside the magnetic material; and
including a cooler disposed outside the housing and connected to the microchannel,
electric vehicle.
14. The method of claim 13,
The electric vehicle, wherein the cooler comprises an automobile air conditioner.

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