KR20200052034A - Wireless charging pad and wireless charging apparatus - Google Patents

Abstract

The present invention relates to a wireless charging pad comprising: a transmitting/receiving coil which is formed by being wound with a wire; and at least one magnetic body arranged near the transmitting/receiving coil, wherein the magnetic body comprises a first block core, and a second block core aligned with the first block core in the extending direction of the wire. Therefore, an effect caused by voids formed when arranging a plurality of block cores is minimized.

Description

Wireless charging pad and wireless charging apparatus

The present invention relates to a wireless charging pad and a wireless charging device.

As research into electronic devices continues, research into wireless charging systems that supply electrical energy to electronic devices is also being conducted.

Many companies are devoted to research and development of wireless charging systems for mobile terminals and wireless charging systems for electric vehicles. Such a wireless charging system includes several electronic components, including a wireless charging pad and a resonant tank for impedance compensation. The wireless charging pad includes a magnetic material, and in order to transmit and receive high power, the wireless charging pad must be large and a magnetic material having a large surface area must be used accordingly. In order to produce a magnetic body having a large surface area, there are difficulties in the process, and there is a problem in that production costs are increased. In addition, a magnetic body having a large surface area has a brittleness problem.

Publication No. 10-2005-0096068 (hereinafter referred to as a prior art document) relates to a design method for a contactless battery charging system capable of multi-charging and its core block. Suggests a way to make it. The prior literature is configured such that both ends are bent so that the horizontal coil wraps a flat core made of a plurality of coils so that wireless charging is possible regardless of the direction of the magnetic flux. In the prior literature, there is a problem in that heat is generated or power transmission efficiency is deteriorated by voids formed while arranging the same block core at random without considering the direction of magnetic flux.

In order to solve the above-mentioned problem, the present invention has an object to provide a wireless charging pad that minimizes the effect of voids formed when a plurality of block cores are disposed.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, in the wireless charging pad according to the embodiment of the present invention, the first block core and the second block core are arranged side by side in a direction in which the wires of the transmitting and receiving coils extend.

Details of other embodiments are included in the detailed description and drawings.

According to the present invention, there are one or more of the following effects.

First, when the magnetic body is placed in a block core, by minimizing the magnetic resistance according to the air gap, the inductance reduction is reduced, and the heating of the magnetic body itself is reduced, thereby increasing the efficiency of the entire wireless charging pad.

Second, by minimizing the magnetic resistance according to the air gap, it is possible to increase the inductance efficiency, thereby making it possible to design the entire magnetic body size small.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a view showing the appearance of a wireless charging system according to an embodiment of the present invention.
2 is a block diagram of a wireless charging system according to an embodiment of the present invention.
3 is a view referred to for describing a wireless charging method according to an embodiment of the present invention.
4 illustrates an equivalent circuit of a wireless charging pad according to an embodiment of the present invention.
5 is a view referred to for explaining the configuration of a wireless charging pad according to an embodiment of the present invention.
6 is a view referred to for explaining a direction of a magnetic flux according to a current direction and a current flowing through a transmission / reception coil and a transmission / reception coil according to an embodiment of the present invention.
7 is a Maxwell simulation (Maxwell simulation) results that can confirm the direction of magnetic flux during magnetic coupling of the receiving pad and the transmitting pad according to an embodiment of the present invention.
8A and 8B are diagrams referred to for describing a magnetic circuit of a wireless charging pad according to an embodiment of the present invention.
9A to 9B are diagrams referred to for explaining the influence of voids according to a method of arranging block cores.
10A is a view referred to for describing a wireless charging pad according to an embodiment of the present invention.
10B and 10C illustrate a first block core and a second block core according to an embodiment of the present invention.
11A to 11C are diagrams referred to for describing a wireless charging pad according to an embodiment of the present invention.

Hereinafter, exemplary embodiments disclosed herein will be described in detail with reference to the accompanying drawings, but the same or similar elements are assigned the same reference numbers regardless of the reference numerals, and overlapping descriptions thereof will be omitted. The suffixes "modules" and "parts" for components used in the following description are given or mixed only considering the ease of writing the specification, and do not have meanings or roles distinguished from each other in themselves. In addition, in describing the embodiments disclosed in this specification, detailed descriptions of related known technologies are omitted when it is determined that the gist of the embodiments disclosed in this specification may be obscured. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical spirit disclosed in the specification is not limited by the accompanying drawings, and all modifications included in the spirit and technical scope of the present invention , It should be understood to include equivalents or substitutes.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from other components.

When an element is said to be "connected" or "connected" to another component, it is understood that other components may be directly connected to or connected to the other component, but there may be other components in between. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, terms such as "comprises" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described in the specification, but one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

1 is a view showing the appearance of a wireless charging system according to an embodiment of the present invention.

2 is a block diagram of a wireless charging system according to an embodiment of the present invention.

Referring to the drawings, the wireless charging system 100 may include a power transmitting device 10 and a power receiving device 20. The wireless charging system 100 may be used for wireless charging of an electric vehicle battery, wireless charging of a robot cleaner, wireless charging of a mobile terminal battery, and the like.

When the wireless charging system 100 is used for wireless charging of an electric vehicle battery, the power transmission device 10 may be installed in a charging station or the like, and the power receiving device 20 may be provided inside the vehicle. When the wireless charging system 100 is used for wireless charging of the robot cleaner battery, the power transmission device 10 may be configured in a portable format, and the power receiving device 20 may be provided inside the robot cleaner. . When the wireless charging system 100 is used for wireless charging of the mobile terminal battery, the power transmission device 10 may be configured in a portable format, and the power reception device 20 may be provided inside the mobile terminal. .

The power transmission device 10 may include an AC / DC converter 11, a DA / AC inverter 12, a resonance tank 13 and a transmission pad 14. The AC / DC converter 11 may convert electrical energy in the form of AC provided from the system 1 into a form of DC. The DC / AC converter 12 converts electrical energy in the form of direct current into electrical energy in the form of alternating current. At this time, the DC / AC converter 12 may generate high-frequency signals of tens to hundreds of kHz. The resonance tank 13 compensates for impedance suitable for wireless charging. The transmission pad 14 transmits electric energy wirelessly. The transmission pad 14 includes a transmission coil 15 therein.

The power receiving device 20 may include a receiving pad 21, a resonance tank 22, and a rectifier 23. The receiving pad 21 wirelessly receives electrical energy. The receiving pad 21 includes a receiving coil 25 therein. The transmitting pad 14 and the receiving pad 21 include a coil set (transmitting coil 15 and receiving coil 25) having magnetic coupling. The transmitting pad 14 and the receiving pad 21 transmit electric energy without physical contact between physical electrodes through a magnetic field generated by a high frequency driving signal. The resonance tank 22 compensates for impedance suitable for wireless charging. The rectifier 21 converts the electrical energy in the AC form to the electrical energy in the DC form in order to supply the DC 30 with electrical energy. The battery 30 may be provided in a vehicle, a robot cleaner, or a mobile terminal.

3 is a view referred to for describing a wireless charging method according to an embodiment of the present invention.

Referring to FIG. 3, the wireless charging system may use an inductive coupling method or a resonance coupling method.

In the inductive coupling method (Inductive Coupling), if the intensity of the current flowing through the primary coil (coil) of the two adjacent coils (coil) changes the magnetic field by the current, thereby passing through the secondary coil (coil) The principle is that the magnetic flux changes and the induced electromotive force is generated on the secondary coil side. That is, according to this method, induction electromotive force is generated when only the current of the primary coil is changed while the two coils are brought into proximity without spatially moving the two conductors. In this case, the frequency characteristic is not greatly affected, but the alignment and distance between the transmitting device (e.g., wireless charging device) and the receiving device (e.g., mobile terminal) including each coil. According to (Distance), power efficiency is affected.

In the resonance coupling method, a part of the amount of magnetic field variation generated by applying a resonance frequency to a primary coil among two coils separated by a certain distance is a secondary coil having the same resonance frequency ( coil) to use the principle that induced electromotive force is generated in the secondary coil. That is, according to this method, when the transmitting and receiving devices each resonate at the same frequency, since electromagnetic waves are transmitted through a short-range electromagnetic field, energy transmission is not performed at different frequencies. In this case, the choice of frequency can be an important issue. Since there is no energy transfer between the resonant frequencies spaced apart by a predetermined distance or more, the device to be charged may be selected through the selection of the resonant frequency. If only one device is allocated to one resonance frequency, the selection of the resonance frequency may have a meaning of selecting a device to be charged soon.

The resonant coupling method has an advantage in that alignment and distance between a transmitting device and a receiving device including each coil have less influence on power efficiency, compared to an inductive coupling method.

4 illustrates an equivalent circuit of a wireless charging pad according to an embodiment of the present invention.

The wireless charging pad 500 according to an embodiment of the present invention may be used as the transmission pad 14 of the power transmission device 10 or the reception pad 21 of the power reception device 20. The wireless charging pad 500 may be used for wireless charging of a small device such as a mobile terminal, but is preferably used for wireless charging of a large device such as an electric vehicle.

Referring to FIG. 4, the wireless charging pad 500 may be used as a pad 500a for power transmission or a pad 500b for power reception. The power transmission pad 500a may include a resonance tank 13 and a power transmission coil 520a. The power transmission pad 500a may be electrically connected to the power converters 11 and 12. The power converters 11 and 12 may include an AC / DC converter 11 and a DC / AC inverter 12 described with reference to FIG. 2. The power receiving pad 500b may include a resonance tank 22 and a power receiving coil 520b. The power receiving pad 500b may be electrically connected to the rectifier 23.

5 is a view referred to for explaining the configuration of a wireless charging pad according to an embodiment of the present invention. 5 illustrates an exploded perspective view of the wireless charging pad. 5 illustrates the receiving pad 21 by way of example. When the transmission pad 14 is based on the ground, only the stacking order of the reception pad 21 is reversed, and the description of FIG. 5 may be applied.

Referring to FIG. 5, the wireless charging pad 500 includes a first case 610, a winding guide 620, at least one transmission / reception coil 520, a magnetic body 510, an aluminum plate 630, an insulating sheet ( 640) and the second case 650.

The first case 610 may form an external appearance of the wireless charging pad 500 together with the second case 650. The first case 610 may be combined with the second case 650 to form a space therein. In the formed space, the winding guide 620, the transmission / reception coil 520, the ferrite plate 510, the aluminum plate 630, and the insulating sheet 640 may be accommodated.

The winding guide 620, the winding guide 620 may be located inside the transmission / reception coil 520. The winding guide 620, when coupled, can be fixed to the transmitting and receiving coil 520 so that it is fixed and does not move. According to an embodiment, the winding guide 620 may be formed integrally with the first case 610. Depending on the embodiment, the winding guide 620 may be omitted. The transmitting / receiving coil 520 is formed in a spiral shape, so that the overall shape may form a circular, elliptical, or polygonal shape. The winding guide 620 may have a circular, elliptical or polygonal shape so that the transmission / reception coil 520 can be wound in a circular, elliptical or polygonal shape.

The transmission / reception coil 520 may be a coil for power transmission. The transmission / reception coil 520 may transmit or receive power wirelessly. When the wireless charging pad 500 functions as the transmission pad 14, the transmission / reception coil 520 may be described as the transmission coil 15. When the wireless charging pad 500 functions as the receiving pad 15, the transmitting / receiving coil 520 may be described as the receiving coil 25. The transmission / reception coil 520 may be formed in a spiral shape. Due to the winding of the transmitting / receiving coil 520, the transmitting / receiving coil 520 may have an overall circular, elliptical, or polygonal appearance. The transmitting and receiving coil 520 may include an incoming line and an outgoing line.

The magnetic body 510 may have a circular, elliptical, or polygonal shape. The magnetic body 510 may be composed of at least one plate. It is preferable to use ferrite for the magnetic body 510. The magnetic body 510 may be disposed while being layered with the transmission / reception coil 520. The magnetic body 510 may be disposed above or below the transmission / reception coil 520. The magnetic body 510 may be disposed inside the transmission / reception coil 520. The transmitting and receiving coil 520 may be wound around the magnetic body 510.

The insulating sheet 640 can shield unintended currents. For example, the insulating sheet 640 can shield the surface current flowing through the magnetic body 510. For example, the insulating sheet 640 may shield the capacitor of the resonant tank 530 from being energized with other components in the wireless charging pad 500.

The insulating sheet 640 may be positioned between the aluminum plate 630 and the magnetic body 510. The insulating sheet 640 may be formed of various insulating materials, but is preferably formed of polycarbonate (PC).

The aluminum plate 630 can shield the magnetic field. The aluminum plate 630 may shield the magnetic field generated in the process of power transmission and / or power reception from leaking to the outside. The aluminum plate 630 may perform a heat dissipation function. The aluminum plate 630 may induce heat generated from the transmission / reception coil 520 and / or the magnetic material 510 in the process of power transmission and / or power reception to the outside of the wireless charging pad 500.

The aluminum plate 630 may be positioned between the magnetic body 510 and the second case 650. For example, the aluminum plate 630 may be positioned under the magnetic body 510.

The second case 650 may form an external appearance of the first case 610 and the wireless charging pad 500. The second case 650 may be combined with the first case 610 to form a space therein.

6 is a view referred to for explaining a direction of a magnetic flux according to a current direction and a current flowing through a transmission / reception coil and a transmission / reception coil according to an embodiment of the present invention.

Referring to FIG. 6, the transmission / reception coil 520 may be disposed above or below the magnetic body 510. The transmission / reception coil 520 may be formed by winding a wire. The wire can be formed of metal. The wire is preferably formed of copper.

The wire of the transmission / reception coil 520 may be wound in a clockwise or counterclockwise direction. For example, the transmission / reception coil 520 may be formed by winding a wire in a clockwise or counterclockwise direction along the circumference of the outer surface of the winding guide 620. For example, the transmission / reception coil 520 has an air core inside, and the wire may be wound in a clockwise or counterclockwise direction.

The transmitting / receiving coil 520 may include a lead-in section 521, a winding-up section 522, and a lead-out section 523. The lead-in portion 521 may be defined as a portion through which current flows into the transmitting / receiving coil 520. The lead-in part 521 may be described as a straight or curved wire part of the transmitting / receiving coil 520 that is not wound. One end of the lead-in portion 521 may be electrically connected to other electronic components. The winding part 522 may be described as a part where the wire is wound in one direction and has a spiral shape. The winding part 522 may be wound in one direction along the circumference of the outer surface of the winding guide 620. The winding part 522 can be extended from the lead-in part 521. The lead-out unit 523 may be defined as a portion through which current flows from the transmission / reception coil 520. The lead-out unit 523 may be described as a straight or curved wire portion of the transmission / reception coil 520 that is not wound. The lead-out portion 523 may be extended from the winding portion 522. One end of the lead-out portion 523 may be electrically connected to other electronic components.

On the other hand, electric current flows into the lead-in portion 521, flows from the winding portion 522, and flows out to the lead-out portion 523. As the current flows through the transmission / reception coil 520, magnetic flux is generated. As illustrated in FIG. 6, the magnetic flux is generated in a direction surrounding the wire toward the right, based on the current traveling direction, by Fleming's right-hand screw rule.

7 is a Maxwell simulation (Maxwell simulation) results that can confirm the direction of magnetic flux during magnetic coupling of the receiving pad and the transmitting pad according to an embodiment of the present invention.

Referring to FIG. 7, the transmission / reception coil 520 may be understood as any one of the transmission coil 15 of the transmission pad 14 and the reception coil of the reception pad 21.

When current flows in two wires adjacent to each other in the same direction, the direction of magnetic flux between the wires and the wires is reversed and canceled. As shown in FIG. 7, the flow of current flowing through the transmission coil 15 can be briefly illustrated by an arrow that turns the winding part clockwise. 7 is a simulation result obtained by multiplying an ampere-turn by a condition of power transmission by magnetic coupling. It can be seen that the magnetic flux flowing from the transmitting pad 14 flows to the side of the receiving pad 25.

Meanwhile, the magnetic body 510 may be understood as one of the magnetic body 510a of the transmitting pad 14 and the magnetic body 510b of the receiving pad 21.

8A and 8B are diagrams referred to for describing a magnetic circuit of a wireless charging pad according to an embodiment of the present invention.

8A illustrates a magnetic equivalent circuit of a typical wireless charging pad, and FIG. 8B illustrates a magnetic equivalent circuit of a wireless charging pad 500 according to an embodiment of the present invention.

In the equivalent circuit of FIG. 8A, the following equation holds.

Equation 1

NI is an ampere-turn, N is the number of turns of the transmit / receive coil 520, I is the current as the source, Ψ is the magnetic flux, Rc is the intrinsic resistance value of the block core, and Rg is caused by the air gap Indicates the resistance value.

As shown in Equation 1, the larger the pores formed where the magnetic flux flows, the larger the total magnetoresistance value becomes. The voids formed in the flux flow act as a loss.

In the equivalent circuit of FIG. 8B, when the resistance value generated by the air gap is negligible, Rg may be expressed as 0. In the wireless charging pad according to the embodiment of the present invention, magnetoresistance caused by voids may be minimized according to the arrangement form of the block core. In the following description, a method of minimizing the magnetoresistance due to voids while using a plurality of block cores is proposed.

9A to 9B are views referred to for explaining the influence of voids according to a method of arranging block cores.

When a block-shaped magnetic material (block core) is arranged side by side, there is no choice but to have physical voids even if they are placed closely together. These physical voids are represented by the resistance (Rg in FIG. 8A).

As illustrated in FIG. 9A, when the pores 910 are formed in the extending direction of the wire according to the arrangement of the plurality of block cores, a number of magnetic fluxes pass through the pores. In this case, the resistance value due to the air gap (Rg in FIG. 8A) has to be large enough to affect the magnetic circuit. In this case, the effective area for the pores 910 in comparison with the magnetic flux direction is forced to increase, and in the region 760 where the pores 920 are formed, all magnetic fluxes are forced to pass through the pores 910.

As illustrated in FIG. 9B, when the pores 920 are formed in a direction perpendicular to the extension direction of the wire according to the arrangement of the plurality of block cores, only a small number of magnetic fluxes pass through the pores. In this case, the resistance value due to the air gap (FIG. 8B) becomes a negligible level. In this case, the magnetic fluxes flow to the magnetic material having a smaller reluctance than the air gap having a high reluctance, and in this case, the effective magnetic field is smaller than the air gap 920 in the region 770 where the air gap 920 is formed due to a small effective area for the air gap 920 in the magnetic flux direction. 920) flows to the surrounding magnetic material (block core).

Meanwhile, the air gap 910 illustrated in FIG. 9A may be a problem in forming the inductance of the transmission / reception coil 520.

Equation 2

L is the inductance of the transmitting and receiving coil 520, λ is the flux linkage, I is the current as the source, N is the number of turns of the transmitting and receiving coil 520, R is the reluctance, and P is the permeance.

The inductance of the transmission / reception coil 520 may be expressed as Equation (2). Inductance is inversely proportional to reluctance, and the reciprocal of reluctance is expressed in permeance. Usually, when designing a wireless charging pad, it is advantageous to design the magnetic material in one plate, but there is a difficulty in the manufacturing process for designing in one plate, and there is a practical problem of increasing production cost. In addition, when a large magnetic body is designed in a single plate, there is a problem that the brittleness of the magnetic body increases. In order to solve these problems, a magnetic body is disposed in which a plurality of block cores are arranged side by side.

When a plurality of block cores are arranged as shown in FIG. 9A, the resistance value (Rg in FIG. 8A) due to the air gap increases, and inductance decreases. That is, the permeance decreases. When a plurality of block cores are arranged as shown in FIG. 9B, the resistance value due to the air gap becomes negligible, so that the decrease in inductance can be minimized.

10A is a view referred to for describing a wireless charging pad according to an embodiment of the present invention.

10B and 10C illustrate a first block core and a second block core according to an embodiment of the present invention. 10B illustrates only the first block core 1010 and the second block core 1020 separately forming the magnetic body 510, and FIG. 10C shows the first block core 1010 and the second block core 1020. Each is individually illustrated.

10A to 10C, the wireless charging pad 500 may include a transmit / receive coil 520 and a magnetic body 510.

The transmitting / receiving coil 520 may transmit or receive power wirelessly by magnetic coupling. The transmission / reception coil 520 may be formed by winding a wire as described with reference to FIG. 6. The wire may extend in a direction intersecting the void 1001. The wire may be wound in a direction intersecting the void 1001. The winding portion, the wire may be wound in a direction intersecting the void 1001.

The magnetic body 510 may be disposed around the transmission / reception coil 510. For example, the magnetic body 510 may be disposed below the transmission / reception coil 510 with respect to the ground. For example, the magnetic body 510 may be disposed above the transmission / reception coil 510 based on the ground. The magnetic body 510 may be in contact with the transmission / reception coil 510.

The magnetic body 510 may include a plurality of block cores. There is no limit to the number of block cores. The block core may be described as a sub magnetic body that is disposed together with another block core to form the magnetic body 510. It is preferable to use ferrite as the block core. The block core may also be described as a magnetic body having a relatively small size compared to the magnetic body 510 covering the entire transmission / reception coil 510.

The magnetic body 510 may include a first block core 1010 and a second block core 1020. The second block core 1020 may be disposed in parallel with the first block core 1010 in a direction in which the wires of the transmission / reception coil 520 extend. The direction in which the wire extends may be described in a direction in which the current flows or in the opposite direction to the direction in which the current flows. Alternatively, the direction in which the wire extends may be described as a direction in which the wire is wound.

The magnetic body 510 may be defined as an object having an intrinsic magnetoresistive component from the product of the number of turns of the transmit / receive coil 520 and the peak value of the current flowing through the transmit / receive coil 520. Here, the intrinsic magnetoresistance component excludes the magnetoresistance component generated by the voids. In FIG. 10, although the magnetic body 510 is illustrated as covering the entire transmission / reception coil 520, the magnetic body 510 may be described in smaller units as illustrated in FIG. 11C.

The first block core 1010 may have a three-dimensional shape. For example, the first block core 1010 may have a plate shape having a specific height value.

The second block core 1020 may have a three-dimensional shape. For example, the second block core 1020 may have a plate shape having a specific height value. The height value of the second block core 1020 may be the same as the height value of the first block core 1010.

In the second block core 1020, one surface may be disposed to face the first block core 1010 to form an air gap 1001. For example, the first side of the second block core 1020 is disposed to face the first side of the first block core 1010, so that the first side and the first block core of the second block core 1020 ( A void 1001 may be formed between the first sides of 1010).

The longitudinal direction 1002 of the void 1001 may be perpendicular to the extending direction 1009 of the wire. The second block core 1020 is disposed in parallel with the first block core 1010 in a direction in which the wires of the transmission / reception coil 520 extend, and one surface of the second block core 1020 has a first block core 1010. The voids 100 formed by facing each other have a longitudinal direction 1002 perpendicular to the extending direction 1009 of the wire. Accordingly, only a small number of magnetic fluxes pass through the air gap 1001, or there is no magnetic flux passing through the air gap 1001, and the magnetic flux is the first block core 1010 and the second block core 1020 around the air gap 1001. ). In this case, the longitudinal direction 1002 of the air gap 1001 may be the same as the direction of the magnetic fluxes 1011 and 1021 flowing from the magnetic body 510 around the air gap 1001. The longitudinal direction 1002 of the air gap 1001 may be the same as the direction of magnetic fluxes 1011 and 1021 flowing in the first block core 1010 and the second block core 1020. The longitudinal direction 1002 of the void 100 may be parallel to the direction of at least one magnetic flux flowing in the magnetic body 510.

Meanwhile, the inductance of the transmission / reception coil 520 may have a relationship with the formation direction of the void 1001. As the amount of magnetic flux passing through the void 1001 increases, the resistance value (Rg in FIG. 8A) generated by the void 1001 increases. Accordingly, the reluctance increases, and the inductance value of the transmission / reception coil 520 decreases. As the amount of magnetic flux passing through the void 1001 decreases, the resistance value generated by the void 1001 decreases. Accordingly, the reluctance decreases, and the inductance value of the transmission / reception coil 520 increases.

As illustrated in FIGS. 10B and 10C, the first block core 1010 is a first block core 1010 facing the second block core 1020, and the first block core 1010 is facing the second block core 1020. It may be formed in a plate shape with one side 1015 as any one side. The second block core 1020 may be formed in a plate shape with the second surface 1025 facing the first surface 1015 as any one side surface. An air gap 1001 may be formed between the first surface 1015 and the second surface 1025.

The first block core 1010 may have a polygonal cross-section 1010a in which the first side 1011a consists of one side. 10B illustrates that the cross section of the first block core 1010 is square, but is not limited thereto, and the cross section of the first block core 1010 is triangular, pentagonal, hexagonal, heptagonal, octagonal, octagonal, or octagonal. Can be

The second block core 1020 may have a polygonal cross-section 1020a in which the second side 1021a having the same length as the first side 1011a is composed of one side. 10B illustrates that the cross section of the second block core 1020 is square, but is not limited thereto, and the cross section of the second block core 1020 is triangular, pentagonal, hexagonal, heptagonal, octagonal, octagonal, or octagonal. Can be

Meanwhile, the magnetic body 510 may further include a third block core 1030. The third block core 1030 may have a three-dimensional shape. For example, the third block core 1030 may have a plate shape having a specific height value. The height value of the third block core 1030 may be the same as the height value of the first block core 1010.

The third block core 1030 may be arranged side by side with the second block core 1020 in a direction in which the wires of the transmission / reception coil 520 extend. The third block core 1030 may be formed with one surface facing the second block core 1020 to form a void.

The magnetic body 510 may further include a fourth block core 1040. The fourth block core 1040 may have a three-dimensional shape. For example, the fourth block core 1040 may have a plate shape having a specific height value. The height value of the fourth block core 1040 may be the same as the height value of the first block core 1040.

The fourth block core 1040 may be arranged side by side with the third block core 1030 in a direction in which the wires of the transmission / reception coil 520 extend. The fourth block core 1040 may be formed with one surface facing the third block core 1030 to form voids.

The fourth block core 1040 may be arranged side by side with the first block core 1010 in a direction in which the wires of the transmission / reception coil 520 extend. The fourth block core 1040 may be formed with one surface facing the first block core 1010 to form a void.

11A to 11C are diagrams referred to for describing a wireless charging pad according to an embodiment of the present invention.

As illustrated in FIG. 11A, the magnetic body 510 may be plural. For example, the magnetic body 510 may include a first magnetic body 511, a second magnetic body 512, a third magnetic body 513, and a fourth magnetic body 514.

Each of the plurality of magnetic bodies 511, 512, 513, and 514 may be defined as an object having an intrinsic magnetoresistive component to the product of the number of turns of the transmitting and receiving coils 520 and the peak value of the current flowing through the transmitting and receiving coils 520. have. Here, the intrinsic magnetoresistance component excludes the magnetoresistance component generated by the voids.

As illustrated in FIG. 11B, when the longitudinal direction of the voids generated by the arrangement of the plurality of block cores constituting the plurality of magnetic bodies 511, 512, 513, and 514 are the same as the extending direction of the wire, numerous magnetic fluxes are generated. It passes through the air gap. Accordingly, the magnetic resistance value (Rg in FIG. 8A) due to the air gap is increased.

As shown in Fig. 11C, when the longitudinal direction of the voids generated by the arrangement of the plurality of block cores constituting the plurality of magnetic bodies 511, 512, 513, and 514 is perpendicular to the extending direction of the wire, very few Only the magnetic flux passes through the air gap. Accordingly, the resistance value due to the air gap becomes a negligible level.

When the wire of the winding portion is a straight line, as described with reference to FIG. 10A, voids formed according to the arrangement relationship between the first block core and the second block core may be formed in a direction perpendicular to the extending direction of the wire. In this case, the longitudinal direction of the air gap may be perpendicular to the extending direction of the wire. In this case, the longitudinal direction of the air gap may be the same as the direction of magnetic flux flowing in the magnetic material around the air gap.

As indicated by reference numeral 790, when the wire of the winding portion extends in a straight line, the second block core 1020 is disposed in parallel with the first block core 1010 in the direction in which the wire of the winding portion extends, and on the wire. Voids may be formed in a vertical direction.

As indicated by reference numeral 791, when the wire of the winding portion extends in a curve, the second block core 1020 is disposed in parallel with the first block core 1010 in the direction in which the wire of the winding portion extends and the tangent of the curve. A void may be formed in a direction perpendicular to (1101).

As in the embodiment of the present invention, when a plurality of block cores are arranged, the resistance value due to the air gap is lowered, and system efficiency is improved. In addition, the size of the magnetic material requiring a specific inductance is increased, and the size of the entire wireless charging path 500 may be reduced compared to the prior art.

The above detailed description should not be construed as limiting in all respects, but should be considered illustrative. The scope of the invention should be determined by rational interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

500: wireless charging pad

Claims (14)

A transmission / reception coil formed by winding a wire; And
Includes; at least one magnetic body disposed around the transmitting and receiving coil;
The magnetic material,
A first block core; And
A wireless charging pad including; a second block core disposed in parallel with the first block core in a direction in which the wire extends. According to claim 1,
The magnetic material,
A wireless charging pad defined as an object having an intrinsic magnetoresistive component from the product of the number of turns of the transmitting and receiving coil and the peak value of the current flowing through the transmitting and receiving coil. According to claim 1,
The second block core,
A wireless charging pad having one surface facing the first block core to form an air gap. According to claim 3,
The longitudinal direction of the void,
Wireless charging pad perpendicular to the extending direction of the wire. According to claim 3,
The longitudinal direction of the void,
Wireless charging pad in the same direction as the magnetic flux flowing in the magnetic body around the air gap. According to claim 3,
The wire,
A wireless charging pad extending in a direction intersecting the air gap. According to claim 3,
The inductance of the transmitting and receiving coil,
A wireless charging pad that is related to the direction of formation of voids. According to claim 1,
The first block core,
The first block facing the second block core is formed in a plate shape with any one side surface,
The second block core,
The second surface facing the first surface is formed in a plate shape with any one side,
A wireless charging pad in which a void is formed between the first surface and the second surface. The method of claim 8,
The first block core,
A wireless charging pad having a polygonal cross section in which the first side is composed of one side. The method of claim 9,
The second block core,
The wireless charging pad having a second side of the same length as the first side has a polygonal cross-section consisting of one side. According to claim 1,
The transmitting and receiving coil,
Wireless charging pad comprising a; winding in one direction and having a spiral. The method of claim 11,
When the wire of the winding portion extends in a straight line, the second block core is arranged in parallel with the first block core in a direction in which the wire of the winding portion extends to form a void in a direction perpendicular to the wire. Wireless charging pad. The method of claim 11,
When the wire of the winding portion extends in a curve, the second block core is arranged in parallel with the first block core in a direction in which the wire of the winding portion extends, and the voids in a direction perpendicular to the tangent of the curve Wireless charging pad to form a. According to claim 1,
The magnetic material,
Further comprising a third block core disposed in parallel with the second block core in the direction in which the wire extends,
The third block core,
A wireless charging pad in which one side is disposed facing the second block core to form a void.

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