KR20160082585A - Apparatus for Wireless Power Transfer, Apparatus for Wireless Power Reception and Coil Structure - Google Patents

Abstract

The present invention relates to a transmitting apparatus for transmitting power by wireless. The transmitting apparatus for transmitting power by wireless includes: a transmitting apparatus body having a shape of a bowl; and a transmission coil unit for transmitting power to a receiving apparatus by wireless based on power supplied from a power source. The transmission coil unit includes: a spiral coil unit wound on the bottom surface of the transmitting apparatus body; and a helical coil unit wound on the side surface of the transmitting apparatus body, but wound such that a radius of a coil loop becomes larger gradually toward the upper part and extended from the dead end of the spiral coil unit to be wound.

Description

Technical Field [0001] The present invention relates to a wireless power transmitting apparatus, a wireless power receiving apparatus, and a coil structure,

The present invention relates to a wireless power transmission apparatus, a wireless power reception apparatus, and a coil structure, and more particularly, to a wireless power transmission apparatus, a wireless power reception apparatus, and a coil structure, which efficiently transmit power from a wireless power transmission apparatus to at least one wireless power reception apparatus, And more particularly to a wireless charging technology capable of transmitting data.

Generally, near-field magnetic coupling wireless power transmission technology is a technology for wirelessly transmitting power between a power source having a certain frequency and an electronic device. When electric power is applied to a transmission coil at a source, a non-radiation type time- When a receiving coil is placed in a magnetic field formed in a space, a voltage or a current is induced in a receiving coil by a time-varying magnetic field, and power is transmitted wirelessly.

As an example of the wireless power transmission technology, the battery of the wireless terminal can be charged only by placing a wireless terminal such as a smart phone or a tablet on a wireless charging pad that generates a high frequency time-varying alternating current magnetic field. Thus, wireless power transmission technology can provide greater mobility, convenience, and safety compared to wired charging environments using existing wired charging connectors. In addition to wireless charging of wireless terminals, such wireless power transmission technology can be applied to various fields such as electric vehicles, Bluetooth earphones and 3D glasses, various wearable devices, home appliances, underground facilities, buildings, portable medical devices, It is expected to replace the existing wired power transmission environment.

In general, a wireless power transmission / reception system using a non-radiating time-varying magnetic field includes a wireless power transmission device having a transmission coil for supplying power in a wireless power transmission mode, and a reception coil, A wireless power receiving device for charging the cell or supplying power to various electric appliances in real time.

However, in such a wireless power transmission / reception system, the intensity of the magnetic field coupling between the transmission and reception coils can be varied according to various environmental variables such as the transmission coil structure for the transmission coil, the geometrical arrangement and position between the transmission coil and the transmission coil, Accordingly, when the magnetic field coupling strength between the transmitting and receiving coils is changed, the optimum power transmission condition of the wireless power transmitting and receiving system can be changed. For example, a dead zone may occur in which the mutual inductance between the two coils is zero depending on the position and arrangement of the receiving coil relative to the transmitting coil. In a region where the mutual inductance between the transmitting and receiving coils becomes zero, It is very important to minimize the dead zone in the wireless power transmission.

Meanwhile, the three-dimensional wireless power transmission technology enables wireless power transmission even if the receiver in a three-dimensional space having x, y, and z axes is located in any direction, thereby reducing the dead zone area, So that the power transmission can be stably performed. Three-dimensional wireless power transmission technology is mainly used for power transmission to human implantable devices such as capsule endoscope, artificial heart, smart phone using secondary battery, wireless headset and wearable information communication device or wearable medical terminal device .

1 is a view showing an example of a receiving coil of a three-axis winding type according to the prior art. The example shown in Figure 1 is described in R. Carta, G. Tortora, J. Thone, B. Lenaerts, P. Valdastri, A. Menciassi, P. Dario, and R. Puers, "Wireless powering for a self- 25, pp. 845-851, 2009). < Desc / Clms Page number 2 >

The three-axis receiving coil 101 shown in FIG. 1 has a disadvantage in that the receiving circuit becomes complicated because each of the three receiving coils includes a rectifying circuit in the implementation of the wireless power transmission system.

2 is a view showing an example of a transmission coil structure of an arrangement type according to the prior art. An example shown in Fig. 2 is described in Q. Xu, H. Wang, Z. Gao, Z.-H. A novel mat-based system for position-varying wireless power transfer to biomedical implants (IEEE Transactions on Magnetics, vol. 49, no. 8, pp. 4774-4779, August 2013 ).

In the case of the arrangement type transmission coil 201 shown in FIG. 2, power transmission is possible on the transmission plane, but it is difficult to use the transmission coil 201 when the receiver is inclined with respect to the transmission part.

Recently, in order to solve such a problem, a high-efficiency system using a high-frequency AC signal having a frequency of several MHz or more has been proposed in connection with the near-field magnetic coupling power transmission technology. High-efficiency systems using high-frequency ac signals enable the transmission of power up to several meters with high efficiency by using resonant coils with high quality factor (Q-factor) by using frequencies of several MHz or more and reducing the resistance loss of the coils .

On the other hand, in order to realize a high efficiency wireless power transmission system using a frequency band of several MHz, it is important to design a low loss coil in terms of transmission efficiency. However, there is a problem that a skin effect is generated when a current flows into a skin of a conductor due to eddy current in a wireless power transmission in a frequency band of several MHz or more. In order to increase the magnetic field strength of the coil, if the interval between the wires is made smaller and the number of turns of the conductor is increased, the current distribution of the cross section of the conductor is increased by one proximity effect due to the magnetic field- There is a problem in that the phenomenon of collapsing into a large amount can be drastically increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wireless power transmission apparatus capable of performing efficient wireless power transmission or reception by minimizing a dead zone based on an improved structure of a first coil part and a second coil part, Or receiving apparatus. It is another object of the present invention to provide a wireless power transmission / reception system capable of wireless charging even when the positions of the transmission / reception coils do not coincide with each other, and can simultaneously perform wireless power transmission to a plurality of reception devices.

It is another object of the present invention to provide a wire winding method for increasing the magnetic field strength and lowering the loss resistance of the coil to increase the transmission efficiency in the wireless power transmission and a coil structure using the wire winding method.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, unless further departing from the spirit and scope of the invention as defined by the appended claims. It will be possible.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a wireless power transmission apparatus in one aspect. Wherein the wireless power transmission device comprises: a bowl-shaped transmission device body; And a transmit coil portion for wirelessly transmitting power to the receiving device based on power supplied from the power source. Wherein the transmission coil unit includes: a spiral coil part wound on a bottom surface of the transmission device body; And a helical coil part which is wound on a side surface of the transmission device body and is wound so that the radius of the coil loop becomes larger toward the upper part.

The helical coil part may extend from an end of the spiral coil part and be wound. The inclination of the helical coil may be between 5 degrees and 90 degrees from the bottom surface. At least one of the spiral coil portion and the helical coil portion may be wound at an equal interval within a predetermined error range with a plurality of conductors having the same radius in a predetermined section. Wherein the transmission coil unit is based on a magnetic field intensity when the arrangement of the receiving coil units is parallel or perpendicular to the transmission coil unit in accordance with an environmental condition in which magnetic flux density of the receiving coil unit of the receiving apparatus is maximum or minimum .

The wireless power transmission apparatus may further include a source coil unit receiving power from the power source and transmitting the power to the transmission coil unit. The wireless power transmission apparatus may further include at least one matching unit for adjusting an impedance matching in the transmitting coil section according to a load of the receiving apparatus. The matching unit may further include a transmitting coil for receiving power from the power source and transmitting the power to the transmitting coil part and a source coil part independent of the transmitting coil. The frequency of the transmitting coil part may be adjusted to be equal to the resonant frequency of the wireless power system including the wireless power transmitting device and the receiving device.

One or more capacitors may be connected in series or in parallel at the end of at least one of the spiral coil portion and the helical coil portion. At least one of the spiral coil portion and the helical coil portion may be wound with any one of a circular coil, a polygonal coil, and an elliptical coil.

The spacing between the wires based on the radius of the conductor, the total width of the coil portion, and the number of turns of the coil can be determined for the plurality of conductors constituting the spiral coil portion and the helical coil portion. At least one of the spiral coil portion and the helical coil portion may be wound so as to have a uniform gap between the loops.

The transmitting device body includes: a first case; And a second case coupled with the first case, and a groove for arranging the spiral coil part and the helical coil part may be formed between the first case and the second case. Wherein the helical coil portion is wound along a side surface of the first case and the second case includes at least a portion of the helical coil portion and at least a portion of the helical coil portion, can do.

The spiral coil portion may be powered by a first AC source and the helical coil portion may be powered by a second AC source. It is possible to acquire the sensing data of the power received by the receiving device. The wireless power transmission apparatus may further include a control unit for controlling an output power of the first AC source and the second AC source based on the sensing data.

Wherein the control unit controls the spiral coil part and the helical coil part to supply more power to the receiving part than to transmit more power to the receiving part, As shown in Fig. The control unit may control the first AC source and the second AC source to supply predetermined power and receive the sensing data from the receiving apparatus based on the control.

According to another aspect of the present invention, there is provided a wireless power transmission apparatus. The wireless power transmission apparatus includes: a bowl body; A spiral coil part forming a magnetic field for supplying radio power from a bottom surface of the bowl body; And a helical coil portion for supplying radio power from the side surface of the bowl body. A magnetic field for supplying radio power to a wider spatial region than when the spiral coil portion and the helical coil portion are individually provided can be formed.

The spiral coil portion is disposed on the bottom surface of the bowl body. The helical coil portion is wound along the side surface of the bowl body, and the coil loop is wound so that the radius of the coil loop increases toward the upper portion.

According to another aspect of the present invention, there is provided a wireless power receiving apparatus. The wireless power receiving device includes: a bowl-shaped receiving device body; And a receiving coil portion for receiving power supplied from the wireless power transmission device. Wherein the receiving coil unit includes: a spiral coil part wound on a bottom surface of the receiving device body; And a helical coil part wound on a side surface of the receiving device body, the helical coil part being wound such that the radius of the coil loop becomes larger toward the upper part.

The helical coil part may extend from an end of the spiral coil part and be wound. The receiving coil unit may further include at least one matching unit for adjusting impedance matching in the receiving coil part according to a load of the receiving device. The matching unit may further comprise an impedance matching circuit configured with a receiving coil for receiving power from the transmitting coil part and a parallel-to-serial capacitor with the load of the receiving device.

According to another aspect of the present invention, there is provided a coil structure. The coil structure includes a spiral coil part wound in a two-dimensional plane in a plane, the coil structure being provided in a transmitting device or a receiving device for wireless power transmission. And a helical coil part wound in a vertical direction from the spiral coil part and wound so that the radius of the coil loop becomes larger toward the upper part. The helical coil part may extend from an end of the spiral coil part and be wound.

According to another aspect of the present invention, there is provided a coil structure. A coil structure including a coil portion for wireless power transmission or reception, wherein a plurality of conductors having the same radius in a predetermined section are arranged at equal intervals within a predetermined error range, and distances between centers of adjacent conductors Can be determined on the basis of the skin effect generated in the conductor when the same current flows through the conductor, and the loss resistance due to the proximity effect generated between adjacent conductors.

The coil portion may be at least one of a spiral coil and a helical coil, and a single lead wire may be wound in the number of turns corresponding to the number of the plurality of lead wires in the predetermined section according to the even spacing.

The distance P between the centers of the adjacent conductors is (W - 2r ₀ ) / (N-1). Here, r ₀ is the radius of the wire, W is width, which indicates the number of the conductors the entire width, and N of the coil, for example, W may correspond to some of the radius of the nose in the plane for the spiral coil, In the case of a helical coil, the height of the wire may be wound.

The ratio of the radius of the conductor to the total width of the coil portion may be 0.0018 to 0.25. The distance between the centers of adjacent conductors may be determined based on the minimum resistance per unit length according to the number N of the conductors.

Radius r0, the number N of the coil, and the overall width W of the lead of the lead is a smile ^{_{"r 0 / w = αN β}} + γ". Here,? = 0.6534,? = -1.397,? = 0.001815 can be shown.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the present invention by those skilled in the art. And can be understood and understood.

According to the embodiments of the present invention, it is possible to provide a wireless power transmission / reception system capable of wireless charging even when the positions of the transmission / reception coils do not coincide with each other, and simultaneously performing wireless power transmission to a plurality of reception devices.

Also, according to an embodiment of the present invention, there is provided a wireless power transmission apparatus that minimizes a dead zone based on an improved structure of a horizontal coil section and a vertical coil section, and a wireless power receiving apparatus having a structure capable of efficiently interlocking with the dead zone .

In addition, according to the embodiment of the present invention, it is possible to provide a winding method for increasing the magnetic field strength and lowering the loss resistance of the coil in order to increase the transmission efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
1 is a view showing an example of a receiving coil of a three-axis winding type according to the prior art.
2 is a view showing an example of a transmission coil structure of an arrangement type according to the prior art.
3 is a diagram illustrating an example of a circuit configuration for explaining the concept of a wireless power transmission / reception system according to an embodiment of the present invention.
4 is a perspective view showing an example of a coil structure according to an embodiment of the present invention.
Fig. 5 is an exemplary view for explaining the coil structure shown in Fig. 4 by way of example.
6 is a view showing an example of a mechanical shape of a bowl type transmitter to which the structure of the radio transmission coil shown in FIG. 4 to FIG. 5 is applied.
7 is a cross-sectional view of the circular bowl-type transmitter shown in FIG.
FIGS. 8 and 9 illustrate various embodiments of a coil part shape according to an embodiment of the present invention, in which embodiments of variously adjusting the inclination of a helical coil part in a three-dimensional wireless transmission coil are shown.
10 is a diagram exemplarily showing simulation results of magnetic field intensities in a three-dimensional wireless transmission coil and a general transmission coil according to an embodiment of the present invention.
11 is a diagram showing another example of simulation results of magnetic field strength comparison between a three-dimensional wireless transmission coil and a general transmission coil according to an embodiment of the present invention.
FIG. 12 shows an example of a form in which a three-dimensional wireless transmission coil according to an embodiment of the present invention is manufactured.
13 and 14 show another example of the mechanical shape of the bowl type transmitter to which the structure of the radio transmission coil according to the embodiment of the present invention is applied.
15 is a perspective view showing an example of implementing a transmitter capable of receiving and storing a plurality of receivers and a plurality of receivers thereof according to another embodiment of the present invention.
Fig. 16 is a cross section of the transmitter shown in Fig. 15, showing a section at a position corresponding to the left storage space.
Fig. 17 is a diagram showing an example of each constitution constituting the receiving coil according to the embodiment of the present invention. Fig.
18 and 19 are views showing various other embodiments of the receiving coil according to the embodiment of the present invention.
20 shows an example of a measurement result of mutual inductance between a transmitting coil and a receiving coil according to an embodiment of the present invention.
21 shows another example of the circuit configuration of the wireless power transmission / reception system according to the embodiment of the present invention.
22 is a diagram showing an example of a shape of a compact hearing aid wireless charging system based on a circuit configuration of a wireless power transmission / reception system according to an embodiment of the present invention.
23 shows another example of the circuit configuration of the wireless power transmission / reception system according to the embodiment of the present invention.
24 is a perspective view illustrating an example of a three-dimensional wireless transmission coil structure according to another embodiment of the present invention.
25 is a block diagram showing the configuration of a wireless power transmission system according to another embodiment of the present invention.
26 is a cross-sectional view for explaining a skin effect generated when a current is applied to a conductor.
27 is a cross-sectional view for explaining a proximity effect when two or more conductors are adjacent to each other.
28 is a cross-sectional view of a coil part structure in which a plurality of conductors having a circular cross section are arranged side by side at uniform intervals according to an embodiment of the present invention.
29 to 32 illustrate, respectively, a coil portion or a lead wire structure capable of forming the cross-sectional structure shown in Fig. 28
33 is an exemplary diagram for explaining magnetic field formation in a circular wire structure and an infinite straight wire.
Fig. 34 is a graph showing the curves of | Hz | generated in accordance with the change of D in the inside and outside and the infinite straight line of the circular loop, respectively.
FIG. 35 is a graph showing the curves of | Hρ | occurring in accordance with the change of D in the circular loop and the infinite straight wire.
FIG. 36 is a graph for comparing the loss resistance generated when the distance between the centers of the conductor lines of the coil portion is equal and when it is uneven.
FIG. 37 shows the ratio of the radius of the conductor with which the loss resistance is minimized to the total width of the coil portion according to the number of turns N of the coil portion.
38 is a graph showing the curve of the loss resistance value per unit length of the number N of turns of the coil part according to the change of the ratio P / 2r ₀ between the distance P between the centers of the conductor lines and the conductor diameter 2r ₀ .
FIG. 39 shows a value of P / 2r ₀ to have the minimum loss resistance according to the number of turns N. FIG.
FIG. 40 is a graph showing the optimum (minimum) loss resistance per unit length according to the number of turns N. FIG.
FIG. 41 is a graph showing the value of P / 2r ₀ for the minimum loss resistance per unit length according to the number of turns N. FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the invention and is not intended to represent the only embodiments in which the invention may be practiced. The following detailed description includes specific details in order to provide a thorough understanding of the present invention. However, those skilled in the art will appreciate that the present invention may be practiced without these specific details.

3 is a diagram illustrating an example of a circuit configuration for explaining the concept of a wireless power transmission / reception system according to an embodiment of the present invention.

3, an equivalent circuit 300 of a wireless power transmission / reception system according to an exemplary embodiment of the present invention includes a transmission side resonance coil stage (hereinafter, referred to as a 'transmission stage') to which an AC source signal V _S 314 is supplied. (Hereinafter referred to as a "receiving end") 320 and a magnetic induction or a magnetic field coupling according to mutual inductance M ₁₂ between the transmitting end 310 and the receiving end 320, Lt; / RTI >

Although not shown in FIG. 3, the AC source signal Vs 314 is output from a power source, and the power source receives a square wave signal and outputs a driving amplifier, a switching power amplifier, and an LC filter The transmitter 310 includes a magnetic inductance L ₁ 311, a resistor R ₁ 312 and a capacitor C ₁ 313 for resonance. The receiving end 320 includes a self inductance L ₂ 321, a resistor R ₂ 322, and a capacitor C ₂ 323 for resonance.

3, the capacitance C ₁ 313 of the transmitting terminal 310 shows a series circuit connected in series to the inductance L ₁ 311 and the resistance R ₁ 312, but is not limited thereto. According to another embodiment, the capacitance C ₁ 313 of the transmitting terminal 310 may be connected in parallel to the inductance L ₁ 311 and the resistance R ₁ 312. Similarly, the capacitor C ₂ 323 of the receiving end 320 shows a series circuit connected in parallel to the inductance L ₂ 321 and the resistance R ₂ 322, but it is not limited thereto, and according to another embodiment capacitor C ₂ (323) may be connected in series to the inductance L ₂ (321) and the resistor R ₂ (322).

Preferably, the equivalent circuit 300 of the wireless power transmission / reception system according to the embodiment of the present invention includes a transmitting terminal 310 and a receiving terminal (not shown) so that the transmitting coil can transmit the maximum power through the electromagnetic induction or the magnetic- 320, for example, a Tx matching unit 315 and a Rx matching unit 324 for impedance matching.

For maximum power transfer, the transmission-side impedance matching unit 315 performs a conjugate matching with the input impedance Zin for the impedance viewed by the transmission coil (Tx coil), and transmits the impedance through the transmission unit impedance matching Thereby minimizing or eliminating reflection of the source signal. The receiving-end impedance matching unit 324 also establishes a conjugate matching condition with the impedance looking from the receiving coil (Rx coil) to the transmitting side to obtain the impedance matching effect on the impedance Z _L (325). At this time, the impedance Z _L (325) means a load such as a rectifier circuit, a DC-DC converter, a battery, a resistor, or an electric appliance.

In the preferred embodiment of the present invention, the receiving end 320 and the transmitting end 310 for receiving and transmitting the wireless power illustrated in FIG. 3 correspond to a mounting means device for transmitting maximum power to small and small devices, respectively . For example, the receiving end 320 may be a small medical device such as a hearing aid, a portable information communication device such as a smart phone, all wearable terminal devices including a rechargeable battery, and various types of peripherals related thereto. The transmitting terminal 310 may be a receiving means or a receiving means capable of supplying wireless power to the receiving terminal 320 with maximum power transmission efficiency. At least one of the transmitting coil Tx Coil of the transmitting end 310 and the receiving coil Rx coil of the receiving end 320 may be a new coil structure proposed in the present invention.

The coil structure of the transmitting unit or the receiving unit according to the embodiment of the present invention includes a spiral coil part wound on a two-dimensional plane in a planar manner and a spiral coil part wound on the spiral coil part three- Helical loops are used to minimize the dead zone in which no induction current is generated from the transmitting coil to the receiving coil in three-dimensional wireless power transmission.

The spiral coil part may be a coil part coiled in a spiral shape on an x, y axis plane in a space of a two-dimensional flat name, for example, x, y and z axes. The spiral coil unit may be implemented in various forms such as a circular spiral coil having a circular planar shape of each loop coil, a polygonal spiral coil having a polygonal plane shape of each loop coil, and an elliptical spiral coil having an elliptical planar shape of each loop coil .

The helical coil portion may be in the form of a helical coil in which the coil is wound in the z-axis direction in a space in the vertical direction, for example, the x, y, and z axes, from the plane in which the spiral coil portion is implemented. The helical coil unit may be implemented in various forms such as a circular helical coil having a circular planar shape of each loop coil, a polygonal helical coil having a polygonal plane shape of each loop coil, and an elliptical helical coil having an elliptical planar shape of each loop coil .

Hereinafter, various embodiments of the coil structure according to the embodiment of the present invention will be described in detail.

FIG. 4 is a perspective view illustrating an example of a coil structure according to an embodiment of the present invention. FIG. 5 is an exemplary view for explaining the coil structure shown in FIG. 4. Specifically, Dimensional wireless transmission coil structure according to an embodiment of the present invention.

The transmission coil 400 according to the embodiment of the present invention shown in FIGS. 4 to 5 includes a spiral coil part 401 formed as a circular spiral coil on a two-dimensional plane, for example, May be wound in a conical-like manner such that the radius of the coil loop is gradually increased, for example, from the plane where the coil loop is formed, for example, the vertical direction from the bottom surface.

At this time, the spiral coil portion 401 and the helical coil portion 402 constituting the transmission coil 400 can use a single conductor for use in the MHz band. For example, the helical coil part 402 may be formed to extend from the end of the outermost loop of the spiral coil part 401. The spiral coil part 401 and the helical coil part 402 have the same radius of curvature and can be implemented with various turns.

In the case of implementing such a structure having multiple turns, it is preferable that the intervals between the turns are equally implemented so as to have the lowest resistance in current transmission. The technique of determining the interval between each turn to have the minimum resistance will be described later in detail with reference to Figs. 24 to 41 and the like.

As shown in Fig. 5, the coil inner region A is generated in the magnetic field H by the structural shapes of the spiral coil portion 401 and the helical coil portion 402. As shown in Fig. The generated magnetic field H is generated as an elliptical region as the magnetic field H _z , H _ρ is generated in the z direction and the ρ direction.

6 is a view showing an example of a mechanical shape of a bowl type transmitter to which the structure of the radio transmission coil shown in FIG. 4 to FIG. 5 is applied.

Referring to FIG. 6, a transmitter 500 according to an embodiment of the present invention includes a circular bowl-shaped bottom plate and a circular bowl-shaped bottom plate on which a transmission coil shown in FIGS. Represents a transmitter.

7 is a cross-sectional view of the circular bowl-type transmitter shown in FIG.

Referring to FIG. 7, a transmitter body 600 according to an embodiment of the present invention includes a first case 601 for forming a bowl-shaped inner portion, and a first case 601 for joining with the first case 601, And a second case 602. At this time, in one embodiment, a protrusion is formed at the lower end of the first case 601, and a groove is formed at the lower end of the second case 602 to receive the protrusion and the protrusion is fitted into the groove, The first case 601 and the second case 602 can be fixed.

A first groove 603 is formed between the first case 601 and the second case 602 to which the transmission coil is to be wound. The spiral coil portion 604 is wound in a plane on the bottom surface of the first case 601 in the region of the first groove 603. [ The helical coil part 605 may extend from the spiral coil part 604 and be wound in a helical shape along the outer circumferential surface of the side surface of the first case 601. For example, the end of the outermost coil of the spiral coil part 604 and the end of the lowermost coil of the helical coil 605 may be connected.

Meanwhile, a second groove 606 through which the coil can be wound may be formed at the lower end of the second case 602, which can be utilized as a space for winding the source coil, which will be described later, of the transmitter.

For example, the second case 602 and the first case 601 are partly spaced apart to form a first groove 603, the first case 601 has a transmitting coil attached thereto and the inner surface of the second case 602 It can be used for attaching shielding material.

The use of the circular bowl type transmitter shown in FIGS. 6 and 7 allows the receiver to be placed inside the bowl type transmitter, so that the receiver can be stored and charged at the same time. For example, a receiver can be implemented as a hearing aid, and a bowl type transmitter can be implemented as a hearing aid storage box. In this case, one or two hearing aids can be stored in the hearing aid storage box, so that the hearing aid can be charged while the hearing aid is stored.

When the receiver is inserted into the transmission coil, the magnetic field is interlinked to the reception coil inside the receiver, so that an induced current can be generated. Therefore, in the design of the transmission coil according to the embodiment of the present invention, assuming an environment in which the magnetic flux density to be bridged to the reception coil is maximum and minimum, the magnetic field intensity when the arrangement of the reception coils is parallel or perpendicular to the transmission coil is calculated , And thus a transmission coil structure capable of controlling the magnetic field is proposed. For example, the designer can implement a desired magnetic field pattern by adjusting the number of turns of the transmission coil, the conductor spacing, and the tilted angle of the pseudo-conical helical coil.

The following equations (1) and (2) show the magnetic field strength in the transmission coil according to the embodiment of the present invention described above with reference to FIG.

Equations (1) and (2) represent the magnetic field strength (H _{Z, i} ) generated in the z direction and the magnetic field strength (H _{ρ, i} ) generated in the ρ direction when the current I flows through the _i- . D _i represents the height in the z direction of the i-th loop, p represents the ρ-direction spacing at an arbitrary point, D represents the z-direction spacing at an arbitrary point, D _i represents the z- And r _i represents the radius of the helical coil constituting the i-th loop. Here, K _i and E _i are respectively a complete elliptical integral and a second-order full elliptic function, respectively, and are calculated by the following equations (3) and (4).

In Equation (3) and Equation (4), m _i is derived by the following equation (5).

Therefore, the total magnetic field in the z direction generated in the transmitter coil of N turns intensity (H _z) and the total magnetic field intensity in the direction of ρ _(ρ H) can be expressed as Equation 6 and Equation 7, respectively.

Next, Figs. 8 and 9 are views showing various embodiments of a coil part shape according to an embodiment of the present invention, in which embodiments of variously adjusting the inclination of a helical coil part in a three-dimensional wireless transmission coil are shown.

8, a three-dimensional wireless transmission coil 700 according to another embodiment of the present invention includes a spiral coil portion 701 and a helical coil portion 702. The outer radius of the spiral coil portion 701 The length D of the helical coil part 702 can be kept the same while the inclination degree? Can be adjusted between 5 ° and 90 ° with respect to the bottom surface. The height of the helical coil part 702 is also H ₁ , H ₂ ,... As the inclination degree varies in a state where the length of the helical coil part 702 is maintained. , H _n, and the like.

On the other hand, when the height H of the helical coil part 802 is fixed in the three-dimensional wireless transmission coil 800 according to another embodiment of the present invention shown in FIG. 9, the inclination angle? °. Accordingly, the radius r _max of the spiral coil portion 801 can be adjusted according to the inclination of the helical coil portion 802.

10 is a diagram exemplarily showing simulation results of magnetic field intensities in a three-dimensional wireless transmission coil and a general transmission coil according to an embodiment of the present invention.

10 (a) shows a magnetic field strength of a three-dimensional wireless transmission coil according to an embodiment of the present invention, FIG. 10 (b) shows a magnetic field intensity in a general helical coil, It is to represent the field strength of a typical spiral coil, in each figure the left indicates the magnetic field intensity of H _z direction for the coil structure right indicates the magnetic field strength H of the _ρ direction to the coil structure.

10A to 10C, the white area 901 is a support for supporting the coil, and a cross section of a circular bowl-type transmitter that performs a role of a receiver of the receiver as shown in FIGS. 6 to 7 Lt; / RTI >

10A is a simulation result on the magnetic field intensity when the receiving coil Rx coil is placed horizontally at a position 5 mm away from the bottom surface and the right drawing shows a simulation result of the receiving coil Rx coil, Is a simulation result concerning the magnetic field intensity when the magnetic recording medium is placed vertically at a position 8 mm away from the bottom surface.

The simulation result of the magnetic field in the transmission coil illustrated in FIGS. 10A through 10C shows the magnetic field strength when the cross-sectional diameter of the conductor constituting the transmission coil is 0.64 mm and 1 A is applied. The height of the coil according to the embodiment of the present invention used in FIG. 10 (a) is 9.1 mm, the spiral loops of the bottom surface have a spacing of 1.5 mm, and the pseudo conical helical loops of the side surfaces have a spacing of 2.14 mm . The helical coil in FIG. 10 (b) and the spiral coil in FIG. 10 (c) are coils each having 7 turns at intervals of 1.5 mm, and the maximum diameters of the coils are 29 mm and 17 mm, respectively.

10, in the magnetic field region generated by the wireless transmission coil, the general helical coil, and the spiral coil according to the embodiment of the present invention, the region marked with a red color has a strong magnetic field in the plus (+) direction And the portion indicated by blue indicates a portion having a strong magnetic field in the minus (-) direction.

10 (a) and 10 (b) / (c), a spiral coil and a helical coil as shown on the left side (Hz) The magnetic field to be generated is wider than the sum of the magnetic field formed when the spiral coil part is provided alone as shown in FIG. 10 (c) and the magnetic field formed when the helical coil part alone is provided as shown in FIG. 10 (b) Thereby forming a magnetic field in the region. That is, when only the spiral coil is used, it has a very low Hz near the outermost periphery of the spiral coil. At this time, as shown in the left figure of Fig. 10 (b), it can be seen that a constant or uniform magnetic field Hz can be obtained on the plane where the receiver is placed through the Hz generated by the helical coil.

In addition, the magnetic field formed by the coil structure in which the helical coil and the helical coil are combined as shown on the right side (Hρ) in FIG. 10 (a) is formed by the spiral coil part alone A magnetic field is formed in a region wider than the sum of the magnetic field formed when the helical coil portion is provided alone and the magnetic field formed when the helical coil portion alone is provided as shown in FIG. 10 (b). Therefore, the mixed structure of the spiral coil and the helical coil can cause a synergy effect due to the coupling of the two coils.

Assuming that the center axis of the receiving coil is formed in the z direction, when the receiving coil is placed horizontally as shown in the left drawing of FIG. 10A, the spiral coil wound around the bottom and the helical coil When the magnetic coupling due to the Hz component is large and the receiving coil is placed vertically as shown in the right figure, it can be seen that magnetic coupling due to the Hρ component generated by the spiral coil and the helical coil largely occurs.

11 is a diagram showing another example of simulation results of magnetic field strength comparison between a three-dimensional wireless transmission coil and a general transmission coil according to an embodiment of the present invention.

The graph of the three-dimensional wireless transmission coil shown in Fig. 11 includes a first transmission coil 1001 composed of a helical coil, a second transmission coil 1002 composed of a spiral coil, a third helical coil part and a third transmission coil Direction magnetic field intensity and the ρ direction magnetic field intensity in the fourth transmission coil 1004 composed of the conical helical coil part and the spiral coil part and controlling the magnetic field strength according to the embodiment of the present invention, . Here, the solid line is the simulation result, and the plurality of points included in the solid line represent the calculation result for each coil structure.

11 (a) shows the z-direction magnetic field strength (H _z ) comparison result at a height H ₁ at a distance of 5 mm from the bottom of the support for each coil, and FIG. 11 (b) ρ direction magnetic field intensity (H _ρ) in 8 ㎜ away height (H ₂₎ from the bottom of the support for comparison shows results. At this time, the heights (H ₁ , H ₂ ) are set in consideration of the size of a small device that can be implemented as a receiver proposed by the present invention, for example, a portable hearing aid.

Specifically, let us examine the result of the magnetic field intensity in each coil.

11 (a) and 11 (b), the first transmission coil 1001 exhibits a low magnetic field strength (H _z , _Hρ ) at the center and a higher magnetic field strength (H _z , H _ρ ). This is due to the magnetic field characteristic of the helical coil constituting the first transmission coil.

On the other hand, in the second transmission coil 1002, the magnetic field H _z in the z direction has a large value at the center and sharply decreases as the distance from the center increases, and the magnetic field H _{ρ in the} ρ direction has a low magnetic field And has a maximum value near the intermediate point of 10 mm. This is due to the magnetic field characteristic of the spiral coil constituting the second transmission coil.

On the other hand, the third transmission coil 1003 and the fourth transmission coil 1004 exhibit characteristics similar to those of the second transmission coil 1002 whose magnetic field strength in the z direction is composed of a spiral coil, and are composed of helical coils in the p direction And exhibits characteristics similar to those of the first transmission coil 1001.

In addition, the fourth transmission coil 1004 has the same coil configuration as that of the third transmission coil 1003, but has a pattern and size similar to those of the magnetic field strength. In the case of the fourth transmission coil 1004, The pitch of the wire, the pitch of the wire, and the inclination of the helical coil, as compared with the third transmission coil 1003.

Therefore, by using the three-dimensional wireless transmission coil according to the embodiment of the present invention, a relatively uniform magnetic field is formed in the magnetic field forming region, the dead zone can be minimized, and the position and arrangement of the receiving coils can be minimized. It can be seen that efficient charging of one or more receivers is possible. That is, free positioning between the transceivers and charging of the multi-receiver becomes possible.

FIG. 12 is a view showing an example of a form of a three-dimensional wireless transmission coil according to an embodiment of the present invention, which is manufactured in accordance with the configuration conditions of the transmission coil described with reference to FIG.

As mentioned in the description with reference to Fig. 10, the transmission coil 1101 shown in Fig. 12 uses a copper wire and has a cross-sectional diameter of 0.64 mm, an overall height of 9.1 mm, a wire spacing of the spiral coil loop 1.5 mm, and the wire spacing of the side helical coil loop is 2.14 mm, each of which is made up of seven turns. The transmission coil 1101 is connected to a lumped constant capacitor to resonate at 6.78 MHz, the inductance of the coil is 6.40 μH, and the resistance is 1.039Ω. Therefore, the quality factor (Q-factor) of the transmission coil at 6.78 MHz is 262.4.

Meanwhile, the transmission coil and the transmitter according to the present invention described above with reference to FIGS. 4 to 11 are limited to the specifications (for example, the number of turns, the coil size, the bowl size, etc.) And may be implemented in various forms and specifications depending on the operating environment and use. In the embodiments of the present invention, the hearing aid and the hearing aid storage structure are described as examples of the receiver and the transmitter, but the present invention is not limited thereto. The receiver and the transmitter may be used in small medical devices, smart phones, iPads, It is needless to say that the present invention can be implemented for various purposes as well.

The transmission coil shown in Figs. 4 to 7 and Fig. 12 has been described above with reference to an example in which the spiral coil portion and the helical coil portion are realized in a circular shape and the transmitter is also formed in a circular bowl shape. However, according to other embodiments of the present invention, the spiral coil portion and the helical coil portion may be realized in various shapes such as a polygonal shape or an elliptical shape as well as a circular shape in the loops thereof.

13 and 14 are views showing another example of the mechanical shape of the bowl type transmitter to which the structure of the radio transmission coil according to the embodiment of the present invention is applied.

13, the horizontal section 1201 of the transmitter 1200 may be formed in a rectangular shape, and the horizontal section 1201 of the transmitter 1300 (as shown in FIG. 14) 1301 may be formed in a hexagonal shape. The spiral coil parts 1203 and 1303 and the helical coil parts 1202 and 1302 are disposed on the lower end part (upper part in the drawing, the upper part in the drawing) and the side outer circumferential surface of the transmitters 1201 and 1301 shown in Figs. Can be realized. The horizontal cross section of the transmitter can be implemented in various forms such as polygonal and elliptical.

15 is a perspective view showing an example of implementing a transmitter capable of receiving and storing a plurality of receivers and a plurality of receivers thereof according to another embodiment of the present invention.

As shown in FIG. 15, another embodiment of the present invention shows an embodiment in which the transmitter 1220 is implemented in the form of a hearing aid case, and the receiver hearing aid can be stored and charged. The transmitter 1220 includes storage spaces 1221 and 1222 capable of storing right and left hearing aids respectively and a cover 1223 is provided so as to cover the storage spaces 1221 and 1222 and safely store them. The above-mentioned coil structure may be installed in the interior corresponding to each of the receiving spaces 1221 and 1222 of the transmitter 1220.

Fig. 16 shows a cross section of a position corresponding to the left storage space 1221 as a section of the transmitter 1220 shown in Fig.

As shown in FIG. 16, a spiral coil portion 1227 is provided on the inner bottom surface of the left storage space 1221, and a helical coil portion 1225 is provided on the inner side surface. The spiral coil portion 1227 and the helical coil portion 1225 may have a rectangular planar shape corresponding to the rectangular accommodation space 1221. That is, the spiral coil portion 1227 and the helical coil portion 1225 may be a rectangular spiral coil and a rectangular helical coil.

By implementing the hearing aid case shown in Figs. 15 to 16, it is possible to automatically charge the hearing aid while storing the hearing aid in the case. At this time, a fast charging function is provided to enable charging as fast as possible, and a battery having a capacity larger than the capacity of the hearing aid battery can be installed in the case, so that the hearing aid can be charged several times.

Meanwhile, the receiver coil mounted on the receiver according to the embodiment of the present invention can be wound on a plate-shaped support. Hereinafter, various embodiments of the receiving coil will be described with reference to FIGS. 17 to 19. FIG.

Fig. 17 is a diagram showing an example of each constitution constituting the receiving coil according to the embodiment of the present invention. Fig.

A receiving coil 1400 shown in FIG. 17A is a coil mounted on a receiver. When a large plane constituting a support is defined as a first plane and a face opposite to the first plane is defined as a second plane , The receiving coil 1400 includes a first horizontal coil portion 1401 that is horizontally coiled on the first plane of the support, a vertically coiled vertical coil portion 1402 that is wound on a side surface of the support, And a second horizontal coil part 1403 wound on the first horizontal coil part 1403. At this time, the first horizontal coil part 1401 and the second horizontal coil part 1403 use a spiral coil, and the vertical coil part 1402 uses a helical coil.

The spiral coil portion and the helical coil portion can be implemented with a structure having multiple turns using a single conductor to use a frequency of ㎒ or higher. For example, the overall size of the receiving coil 1400 is designed in a rectangular structure of 10.5 mm in width, 6.5 mm in length, and 2.46 mm in height, and the spiral coil 1400 constituting the first horizontal coil part 1401 and the second horizontal coil part 1403, And the helical coil constituting the vertical coil part 1402 is constituted by 7 turns, and the respective coils may be connected in series to each other. Preferably, in the case where the coil structure is implemented by using several turns in each coil part, the interval between each turn of the coil may be equalized to obtain the lowest resistance.

In addition, a structure having magnetic characteristics in accordance with the shape of the reception coil can be used for focusing the magnetic flux inside the reception coil. For example, as shown in FIG. 17 (b), a support 1404 of a ferrite rectangular parallelepiped can be realized with a rectangular plate-like structure in which a plurality of ferrite sheets having a permeability of 100 are stacked.

Fig. 17C shows an example of the reception coil fabricated with the configuration shown in Figs. 17A and 17B. The manufactured receiving coil 1405 was manufactured in the same manner as the coil standard referred to in FIG. 17A. The manufactured receiving coil 1405 has a rectangular structure of 10.5 mm in width, 6.5 mm in length and 2.46 mm in height, 8 turns in the spiral coil, Each coil is connected in series with each other, and a copper wire having a diameter of 0.25 mm is used. Further, the receiving coil 1405 is connected to the LC capacitor so as to resonate at 6.78 MHz. The inductance of the manufactured reception resonance coil 1405 is 3.09 μH and the resistance is 3.400 Ω. Therefore, the quality factor of the receiving coil at 6.78 MHz is 38.7.

Meanwhile, the receiving coil according to the embodiment of the present invention can be implemented in various forms as well as the rectangular shape shown in FIG.

18 and 19 are views showing various other embodiments of the receiving coil according to the embodiment of the present invention.

Referring to Figs. 18 and 19, there is shown an example of a receiving coil 1500 of a circular shape and a receiving coil 1600 of a hexagonal shape, respectively.

As shown in FIGS. 18 and 19, the first and second spiral coil parts 1501 and 1601, the helical coil parts 1502 and 1602, and the second spiral coil parts 1501 and 1602 are formed in accordance with the shapes of the receiving coils 1500 and 1600, And portions 1503 and 1603 may be stacked.

Further, although not shown in Figs. 18 and 19, a plate-shaped support such as a ferrite sheet portion in the form of a circle and a hexagon, respectively, may be further included to support the receiving coil.

The proposed receiver coil structure can be applied to the proposed transmission coil structure, but it can be applied to other types of transmission structures. For example, it can be applied to a flat spiral structure or a box-shaped coil structure.

20 is a diagram illustrating an example of a measurement result of mutual inductance between a transmission coil and a reception coil according to an embodiment of the present invention. Specifically, the measurement result of the mutual inductance between the transmission coil and the reception coil varying according to the reception coil arrangement is .

FIG. 20A shows the result of mutual inductance measurement when the receiving coils are arranged parallel to the transmitting coil, and FIG. 20B shows the result of mutual inductance measurement when the receiving coils are arranged perpendicular to the transmitting coil. The transmitting coil and the receiving coil used in this case are the transmitting coil and the receiving coil according to the embodiment described above with reference to FIGS. 12 and 17, and the positions of the respective coils are the same as those of the receiving coil used in the simulation shown in FIG. 10 . That is, in the parallel arrangement, the receiving coil is located at a position 5 ㎜ away from the bottom of the support, and in the vertical arrangement, the receiving coil is located at a position 8 ㎜ away from the bottom of the support.

As shown in FIG. 20 (a), in the parallel arrangement, the mutual inductance between the transmitting coil and the receiving coil is about 350 nH at the center, and decreases with the outer angle. As shown in FIG. 20 (b), in the case of the vertical arrangement, the mutual inductance between the transmitting coil and the receiving coil is about 2.25 nH at the center, and increases up to the outer angle to have a maximum of 178.5 nH. In addition, the mutual inductance increases when moving in the vertical direction from the x-axis, but when moving in the y-axis, the receiving coil can be almost zero because not only the z-direction but also the ρ-direction magnetic field can not be bridged.

On the other hand, the maximum efficiency (? ^Max ) that the wireless power transmission / reception system can have through the resistance and the mutual inductance of the transmission coil and the reception coil can be derived by the following equation (8).

Referring to Equation (8), the maximum efficiency (eta ^max ) of the wireless power transmission / reception system shows a maximum efficiency of 80.11% at the center of the transmission coil when the transmission coil and the reception coil are arranged in parallel, The efficiency of 61.3% can be obtained at the point of ρ = 3 cm. This is the theoretical maximum efficiency that can be possessed in the transmission and reception resonance coils, and appropriate impedance matching may be required to achieve this maximum efficiency.

In the above-described embodiments, the coil structure shown in FIGS. 4 to 5 is implemented as a transmission coil and the coil structure shown in FIG. 17 is implemented as a reception coil. However, in another embodiment of the present invention According to this embodiment, the coil structure shown in Figs. 4 to 5 may be implemented as a reception coil, and the coil structure shown in Fig. 17 may be implemented as a transmission coil. For example, the another embodiment is a configuration in which at least a part of the receiver is configured in a bowl shape, and a reception coil is implemented with a spiral coil part and a helical coil part. That is, the proposed improved coil structure according to the invention, for example a coil structure comprising a spiral coil part and a helical coil part, can be applied to at least one of a transmitting coil and a receiving coil.

21 is a diagram showing another example of a circuit configuration of a wireless power transmission / reception system according to an embodiment of the present invention. Specifically, FIG. 21 shows a circuit configuration diagram for performing impedance matching in order to maximize the efficiency of the wireless power transmission / .

Referring to FIG. 21, a wireless power transmission / reception system according to another embodiment of the present invention includes a transmitter 1800a and a receiver 1800b.

The transmitter 1800a is composed of a source coil 1801 and a transmission resonance coil 1802 for input impedance matching (Tx impedance matching). The source coil 1801 is connected to a source having an inductance (L _S ) of the source coil, an integrated distributed capacitor (C _S ) connected to the source coil, a loss resistance (R _S ) and a characteristic impedance Z ₀ . At this time, the capacitor C _S may not be used depending on the circuit conditions.

The transmission resonance coil 1802 is configured such that the inductance L ₁ of the transmission resonance coil for input impedance matching with the source coil 1801, the capacitor C ₁ connected to the transmission resonance coil, and the resistor R ₁ are connected in series Respectively. The circuit of the transmission resonant coil 1802 is distinguished in that it performs impedance matching with the source coil 1801 as compared with the equivalent circuit of the transmitter 310 described above with reference to FIG.

Source coil 1801 and the transmission resonance coil 1802 may perform transmitting the input impedance matching adjustment through the cross-impedance (M _S). However, the present invention is not limited to the illustrated matching circuit, and various matching circuits can be used. For example, a structure in which a transmission resonance coil part and a direct capacitor are connected without using a source coil can be used. In this case, the capacitors may be configured in series, parallel, serial-parallel, or parallel-serial.

When fabricated according to the source coil shown in Fig. 21, the source coil may be a spiral coil having a radius of 11 mm and a conductor spacing of 2 mm and consisting of two turns. Further, the source coil may be located on the bottom surface of the transmission coil. For example, the source coil may be provided at the lower end of the transmission coil by being wound using a second groove (H ₂ ) provided inside one side of the bottom surface of the transmitter as shown in Fig. The exemplary inductance of the source coil is 150 nH and M _S = 364 nH.

On the other hand, the receiving end of the receiver 1800b includes a receiving resonant coil 1803 and a receiving impedance matching circuit 1804. The reception resonance coil 1803 includes a circuit configuration including the transmission resonance coil 1802 and the inductance L ₂ of the reception resonance coil for output impedance matching and the loss resistance R _{2 of the} coil, 1802 and an output impedance matching (Rx impedance matching).

Receiving an impedance matching circuit 1804 is a capacitor (C _2, C _P) of the to use a capacitor of C ₂ and C _P for impedance matching implementation, the receiving resonance coil 1803 and the receiver impedance matching circuit 1804 is a view with Can be implemented in parallel or serially. In parallel and serial implementation, more power is supplied to a load with low impedance looking from the receiving coil to the load when charging multiple devices.

Although not shown in FIG. 21, the mutual impedance may exist between the source coil 1801 and the reception resonant coil 1803, and can be neglected when the magnitude does not greatly affect the performance of the system. However, when the source coil 1801 and the reception resonant coil 1803 are very close to each other or when several receivers are simultaneously charged, accurate impedance matching needs to be considered.

The capacitor of the receiver receiving end of the (1800b), that is receiving the resonance coil 1803 and the receiver impedance-matching circuit (1804) (C _2, C _P) has a rectifier circuit 1805, the charging circuit (LTC4070; 1806), Li- ion battery Receiving circuit 1807, a DC-DC converting circuit 1808, and a load 1809 are connected in parallel. Here, the DC-DC conversion circuit 1808 uses LD6806, which is an LDO circuit, and the load 1809 can use a hearing aid.

At this time, the parallel resonant circuit of the receiving resonant coil 1803, the capacitors (C _{2 ,} C _P ) and the receiving signal processing circuit of the receiving section impedance matching circuit 1804 implements the parallel- The load current is limited to 20 mA to prevent battery overcurrent, so that the load impedance has an impedance of several hundreds of ohms. This impedance value is higher than a battery that is charged with a high current such as a conventional smart phone, This is to prevent the efficiency of the wireless charging system from being reduced when using a resonant circuit.

Therefore, it is preferable that the receiving section impedance matching circuit 1804 be a parallel resonant circuit in which the receiving resonant coil, the capacitor, and the load are connected in parallel to each other. For example, the capacitor C ₂ ≠ 0 connected in parallel with the receiving coil 1803 and the capacitor C _p = 0 connected in series can be configured.

However, the present invention is not limited to the parallel resonance circuit as shown in FIG. 21, and may be configured as any one of a series-parallel circuit, a parallel circuit, and a matching circuit using a series capacitor according to an implementation method. In addition, like the transmitting unit 1800a, matching may be performed by placing a receiving resonant coil and a load coil connected to the rectifying circuit.

The received signal processing circuit of the receiver 1800b includes a half-wave rectifying circuit 1805 for converting the voltage induced in the reception resonant coil 1803 to DC, a perceptive red LED 1805c, a battery charging An IC 1806 and a Li-ion battery 1807. [

Since the Li-ion battery 1807 has a voltage of 4.2V in a normal state, and the hearing aid corresponding to the load 1809 operates at a voltage of 1.4V, the battery voltage can be used by a hearing aid, Lt; / RTI > For example, the LDO 1808 used in the receiving circuit is an NXP LD6806, and the measured hearing aid applied voltage may be 1.417V.

The rectifying circuit 1805 is constituted by a half-wave rectifying circuit using only one diode 1805a, not a full-wave rectifying circuit, to reduce the size of the receiving signal processing circuit. At this time, the diode 1805a can be implemented by a low current rectifier diode having a threshold voltage of 0.55 V, for example, by the DB27316 of Panasonic Corporation. The smoothing capacitor 1805b connected in parallel to the diode 1805a for smoothing the rectified voltage may have a value of 116 하여, for example, by connecting a common RF capacitor in parallel to minimize the ripple voltage.

The red LED 1805c for charging recognition is connected to inform the charging state. In the charging state, the voltage difference between the output voltage of the rectifying circuit 1805 and the input voltage to the charging IC 1806 can be fixed to the threshold voltage of the LED 1805c. For example, in order to charge the Li-ion battery 1807 with a low current, the charging IC 1806 can use the LTC4070 manufactured by Linear Technology. At this time, the IC 1806 can charge up to 50mA at a minimum of 450V.

As described above, the wireless power transmission / reception system including the circuit configuration diagram shown in FIG. 21 can be implemented as a wireless charging system for a small-sized hearing aid.

22 is a diagram showing an example of a shape of a compact hearing aid wireless charging system based on a circuit configuration of a wireless power transmission / reception system according to an embodiment of the present invention.

FIG. 22 (a) shows a shape of a wireless hearing aid wireless charging system produced by reflecting the transmitter circuit diagram mentioned in the description of FIG. 21 (a), and FIG. 22 (b) The shape of the receiving coil and the receiving circuit manufactured by reflecting the receiver circuit diagram prepared to be coupled with the receiving resonant coil mentioned in the explanation is shown.

Referring to FIG. 22 (a), the hearing aid corresponding to the receiver is Maxo-K, which is an omnidirectional model of the Korean hearing aid, and the outer size is 18 mm in length and 15 mm in width. The Li-ion battery is pouch-shaped, and the cell size is 10 mm width, 10 mm length, and 4.09 mm height. FIG. 22 (b) shows a shape in which a receiving coil and a receiving circuit are manufactured. The receiving coil and the receiving circuit are combined to have a height of 4 mm. The receiving circuit is fabricated on a 0.4 mm FR4 board and is of a size that can be embedded in a hearing aid together with the receiving coil.

As described above, the wireless power transmission / reception system including the circuit configuration diagrams shown in FIGS. 21 and 22 has been applied to charging a small Li-ion battery developed for driving a small hearing aid. However, various wearable medical terminals, wearable information communication terminals, Phone and the like.

23 is a diagram showing another example of a circuit configuration of a wireless power transmission / reception system according to an embodiment of the present invention. Specifically, in an example of transmitting power from a transmitter to a plurality of receivers, for example, a first receiver and a second receiver Is a circuit diagram showing a corresponding equivalent circuit.

23, the transmitter 2301 receives radio power based on magnetic induction or magnetic coupling according to the mutual inductances M12 and M13, respectively, with the first receiver 2302 and the second receiver 2303, Lt; / RTI > The transmission coil of the transmitter 2301 shown in Fig. 23 may be the proposed coil structure of the present invention shown in Figs. 4 to 5 described above. For example, the example shown in FIG. 23 may be structurally a state in which a plurality of receivers are placed in a bowl-shaped transmitter 2301. For example, the parameters of the transmitter described in the description of FIG. 21 described above can be applied to the related parameters of the transmitter 2301 shown in FIG. 23, and the related parameters of the first receiver 2302 or the second receiver 2303 The parameters of the receiver described in the description of FIG.

The AC source signal Vs of the transmitter 2301 is not shown in FIG. 23 but is output from the power source. The power source receives the square wave signal and transmits only the driving amplifier, the switching power amplifier, LC filters, and the like. The transmitter 2301 includes a self inductance L ₁ , a resistor R _1, and a capacitor C ₁ for resonance. The first receiver 2302 may include a magnetic inductance L ₂ , a resistor R _2, and a capacitor C ₂ for resonance, and the second receiver 2303 may include a magnetic inductance L ₃ , a resistor R _3, and a capacitor C ₃ for resonance .

The circuit diagram shown in FIG. 23 shows a serial circuit in which the capacitor C ₁ of the transmitter 2301 is connected in series with the inductance L ₁ and the resistor R ₁ , but is not limited thereto. According to another embodiment, the capacitor C ₁ of the transmitter 2301 may be connected in parallel to the inductance L ₁ and the resistor R ₁ . Further, 21 is a first capacitor C ₂ of the receiver 2302, but shows a series circuit connected in parallel to inductance L ₂ and the resistor R _2, be this is not limited, in accordance with another embodiment of the capacitor C ₂ is Inductance L ₂ and resistor R ₂ . Similarly, although FIG. 23 shows a series circuit in which the capacitor C3 of the second receiver 2303 is connected in parallel to the inductance L3 and the resistor R3, the present invention is not necessarily limited thereto. According to another embodiment, the capacitor C3 has inductance L3 and resistance R3 can be connected in series.

Preferably, the transmitter 2301 is provided with an impedance matching function for impedance matching with the first receiver 2302 so that the transmission coil can transmit maximum power through the electromagnetic induction or the magnetic field coupling method to the first reception coil and the second reception coil. And a second receiver 2302 may be provided with a reception impedance matching unit Rx impedance unit of the first receiver 2301 for impedance matching with the transmitter 2301. [ Similarly, the second receiver 2303 may include a reception impedance matching unit Rx impedance unit of the second receiver 2303 for impedance matching with the transmitter 2301.

For maximum power transfer, the transmission impedance matching unit performs a conjugate matching with the input impedance (Zin) of the impedance viewed by the transmission coil (Tx coil) and minimizes the reflection of the source signal transmitted through the transmission unit impedance matching Remove. The impedance matching unit of the first receiver 2032 and the impedance matching unit of the second receiver 2303 have impedance Z _L2 And the impedance Z _L3, an impedance and a conjugate matching condition are established from the receiving coil (Rx coil) toward the transmitting side. At this time, the impedance Z _L2 Or impedance Z _L3 may refer to loads such as rectifier circuits, DC-DC converters, batteries, resistors or electrical devices, respectively.

Meanwhile, the coil structure according to one embodiment of the present invention described above, for example, the coil structure shown in FIG. 4 to FIG. 5, has described an example in which the spiral coil portion and the helical coil portion are composed of a single lead wire. For example, the transmission coil portion described above is implemented as a single wire. However, on the other hand, in the coil structure according to another embodiment of the present invention, the spiral coil portion and the helical coil portion may be formed by separate conductors. For example, the transmitting coil part is constituted by a plurality of conductors. Hereinafter, a coil structure according to this embodiment will be described.

24 is a perspective view illustrating an example of a three-dimensional wireless transmission coil structure according to another embodiment of the present invention.

The transmitting coil according to another embodiment of the present invention shown in FIG. 24 includes a spiral coil part 401 'and a spiral coil part 401' formed as a coil in a two-dimensional plane, May include a conical-like helical coil portion 402 'that is wound in a formed plane, e.g., a vertical portion of the coil in the vertical direction from the bottom surface, such that the radius of the coil loop gradually increases.

At this time, the spiral coil portion 401 'and the helical coil portion 402' constituting the transmission coil 400 are implemented as separate conductors physically separated from each other. In other words, unlike the transmission coil part using the single conductor shown in FIG. 4, the transmission coil part shown in FIG. 24 is a structure in which the spiral coil part 401 'and the helical coil part 402' are physically separated from each other.

The spiral coil part 401 'and the helical coil part 402' can be modified into various shapes such as a polygonal shape, an elliptical shape, and the like as well as a circular shape as shown in FIG.

By using such a wireless transmission coil structure, it is possible to implement an efficient transmitter based on active control according to circumstances by connecting an AC source to each of the spiral coil portion 401 'and the helical coil portion 402'.

25 is a block diagram showing the configuration of a wireless power transmission system according to another embodiment of the present invention.

25, the transmitter 2500 may include a first transmitter 2510, a second transmitter 2520, a control unit 2530, and a transmitter communication unit 2540. [ The first transmission unit 2510 may include a first transmission coil 2513, a first impedance matching unit 2512, and a first AC source 2511. Here, the first transmission coil 2513 may be, for example, the spiral coil portion 401 'shown in FIG. The second transmitting unit 2520 may include a second transmitting coil 2523, a second impedance matching unit 2522, and a second AC source 2521. Here, the second transmission coil 2523 may be, for example, the helical coil part 402 'shown in FIG. That is, the spiral coil portion 401 ', which is the first transmission coil 2513, and the helical coil portion 402', which is the second transmission coil 2523, are physically separated from each other and are respectively connected to the first AC source 2511 and the second AC And power is supplied from the source 2521.

The transmitter communication unit 2540 communicates with at least one receiver 2550 and 2560 so that the transmitter 2500 can exchange data with at least one receiver 2550 and 2560. The communication between the transmitter 2500 and the receiver 2550 or 2560 may use in-band communication capable of transmitting and receiving data using a wireless power transmission signal, Other communication methods may be used.

The control unit 2530 can acquire sensing data of the radio power transmitted from the receiver 2550 or 2560 to the transmitter 2540 via the transmitter communication unit 2540. [ The control unit 2530 controls the output size and operation of the first AC source 2511 and the second AC source 2521 based on the obtained sensing data and controls the first impedance matching unit 2512 and the second The impedance matching unit 2522 can be adjusted. That is, the signal of the first AC source 2511 and the signal of the second AC source 2521 have the same phase, but the output power may be changed under the control of the control unit 2530, And the magnitude of the magnetic field generated by the second transmission coil 2523 can be changed.

More specifically, the control unit 2530 initially controls the first AC source 2511 and the second AC source 2521, respectively, and supplies a predetermined constant power to the first transmission coil 2513 and the second transmission coil 2513 2523). Accordingly, the receiver 2500 receives power wirelessly. The receiver 2550 or 2560 may sense the strength of the received power and transmit the sensing data to the transmitter. The control unit 2530 may control the power of the first AC source 2511 and the second AC source 2521 based on the sensing data received from the receiver 2550 or 2560. For example, the control unit 2530 can detect a transmitter capable of transmitting more power to the receiver 2550 or 2560 and control the corresponding AC source to transmit more power to the detected transmitter.

Suppose, for example, that receiver 2550 or 2560 receives more power from spiral coil portion 401 ', i.e., 2510, than helical coil portion 402', i.e., 2520, control unit 2530 may include a spiral coil The first AC source 2511 and the second AC source 2521 can be controlled so that the portion 401 'can supply more power than the portion of the helical coil 402'. Alternatively, if it is assumed that the receiver 2550 or 2560 receives most of the power from the helical coil portion 402 ', i.e., 2520, and receives little power from the spiral coil portion 401', i.e., 2510, The control unit 2530 controls the first AC source 2511 and the second AC source 2521 to supply power only to the helical coil part 402 'and to supply little power to the spiral coil part 401' It is possible.

As such, the control unit 2530 controls the receiver 2550 or 2560 so that more power is supplied to the transmitter in which the receiver 2550 or 2560 receives more power, depending on the position or state of the receiver 2550 or 2560 in the radio power transmission region Or to a transmitter that can hardly transmit power to the receiver 2550 or 2560. Therefore, according to the present embodiment, the efficiency of wireless power transmission is greatly increased, and efficient wireless power transmission is possible.

On the other hand, when there are a plurality of receivers (for example, both 2550 and 2560 are present), the control unit 2530 initially controls the first AC source 2511 and the second AC source 2521, A first AC source 2511 and a second AC source 2512 are connected to the first transmission coil 2513 and the second transmission coil 2523. The first AC source 2511 and the second transmission coil 2523 are connected to the first transmission coil 2513 and the second transmission coil 2523, And the second AC source 2521 to adjust the intensity of the magnetic field generated in the first transmission coil 2513 and the second transmission coil 2523. [

The control unit 2530 may adjust the first impedance matching unit 2512 and the second impedance matching unit 2522 provided in the first transmitting unit 2510 and the second transmitting unit 2520, respectively. For this adjustment, the receiver 2550 or 2560 senses at least one of the voltage and the current measured at the front end or the rear end of the rectifying circuit of the receiver 2550 or 2560 and transmits it to the transmitter 2500, and the control unit 2530 Based on the received sensing data, the first impedance matching unit 2512 and the second impedance matching unit 2522 are adjusted so as to achieve optimum transmission unit impedance matching. Meanwhile, as described above with respect to the embodiments of the present invention, a single metal wire or a plurality of metal wires can be used for coil design in a frequency band of several MHz or more. However, in the case of increasing the number of turns of the conductor of the coil part in order to increase the magnetic field strength in the wireless power transmission, the skin effect of the conductor increases as the frequency increases and as the number of turns of the conductor constituting the coil increases The proximity effect between adjoining wires may increase rapidly and the resistance may increase.

The present invention proposes a coil structure capable of maximizing the strength of a magnetic field by minimizing the loss resistance in consideration of the effect of the proximity effect between the conductors and the skin effect as the number of turns of the conductor constituting the coil portion increases.

Hereinafter, referring to FIG. 26 and FIG. 27, a skin effect and a proximity effect that may occur when a current flows in a conductor will be described.

26 is a cross-sectional view for explaining a skin effect generated when a current is applied to a conductor.

As shown in FIG. 26, when a current I ₀ is applied to a single metal wire 2600 having a wire radius r ₀ , a skin effect occurs in which a current flows into a skin, which is the outermost wire by a vortex current do. Referring to the current density displayed on the conductor cross-section 2600 shown in FIG. 26, the current density at the center of the conductor is close to 0 and the current density increases toward the conductor outside. FIG. 26 shows a simulation result indicating such a phenomenon. As the current density increases, the red region 2601 is displayed. Referring to FIG. 26, it can be seen that the current flow almost rises to the edge portion. This simulation example was performed using the MAXWELL 2D program from ANSYS.

Equation (9) represents the resistance (R _skin ) in the unit length conductor due to the skin effect.

And in the equation _{9, R DC = 1 / (} π (r 0) 2 σ) is, δ = 1 / (π f μ 0 σ) 1/2 (r 0 / δ> 1), r 0 is a wire And σ is the conductivity of the wire. In addition, f is the operating frequency, μ ₀ is the permeability of the conductor, and δ is the skin depth.

27 is a cross-sectional view for explaining a proximity effect when two or more conductors are adjacent to each other.

Referring to FIG. 27, the same current I ₀ flows in the same direction in the first conductor 2710 and the second conductor 2720 having the same size, the radius of the conductor is r ₀ , H is created in the adjacent conductor and displays the magnetic field applied to the other conductor.

It can be seen that the current density is almost close to 0 due to the current hardly flowing in the adjacent regions 2711 and 2721 of the relative conductor line due to the magnetic field H generated by the respective conductors 2710 and 2720 as compared with other regions in the same conductor line This phenomenon is called a proximity effect. Particularly, in the coils used for wireless power transmission and in the coil part structure requiring an increase in the magnetic field strength, if the number of turns of the coils is increased to increase the strength of the magnetic field, the intensity of the magnetic field increases to some extent. The resistance can be abruptly increased by the distance between the wires constituting the coil and the radius of the wire.

The loss resistance (R _ohmic ) per unit length of the wire taking into account the skin effect and the proximity effect can be expressed as Equation (10) below.

As shown in Equation (10), the loss resistance Rohmic per unit length of the conductor is the sum of the resistance Rskin per unit length due to the skin effect and the resistance Rprox per unit length due to the proximity effect. Here, the resistance (Rprox) per unit length due to the proximity effect is the product of Rskin and the proximity factor Gp. Therefore, the loss resistance per unit length of the conductor, Rohmic, can be expressed as the product of Rskin and (1 + Gp), and the unit is Ω / m.

The proximity factor G _P can be calculated by Equation (11) below.

As shown in Equation (11) above, the proximity factor Gp can be determined by x, delta, and H. Where δ represents the skin depth, x represents 2r ₀ / δ (ie, d / δ), and δ and x are the determined values. H is a magnetic field generated by the current flowing in the adjacent wires, and may be varied depending on the number of turns of the coil or the distance between the wires. For example, H may be H shown in FIG.

Therefore, if the magnetic field H generated by the number of turns of the coil or the distance between the conductors is obtained, the proximity factor can be obtained, and the loss resistance Rohmic per unit length can be calculated based on the proximity factor. That is, the proximity factor can be determined according to the mutual influence of the magnetic field generated by the number of turns of the coils or the spacing between the conductors. By using this, the total resistance of the spiral coil structure or the helical coil structure can be determined by R _ohmic and the total length of the coils If you multiply it, you can get it. Due to the effect of the skin effect and the proximity effect, in the conductor design in the high-frequency band of ㎒, the bundle shape with a single lead having a thickness larger than the skin depth (25 袖 m at the skin depth at 6.78 MHz) In the case of a coil structure in which a Ritz coil or a single metal conductor is wound in the shape of a bundle, the proximity factor becomes very large, and the loss resistance rapidly increases, resulting in a significant decrease in efficiency. That is, when the metal wire with the same current is rolled up several turns, the strength of the magnetic field may increase, but the resistance is rapidly increased and the transmission efficiency is actually considerably deteriorated.

Accordingly, the present invention discloses a structure in which, in the structure of a coil portion for wireless power transmission, a plurality of conductors having the same radius in a predetermined section are arranged at equal intervals within a predetermined error range. Here, the distance between the conductor and the wire is determined as an optimized interval that minimizes the loss resistance and maximizes the strength of the magnetic field, taking into account the skin effect of the conductor and the proximity effect between the conductors.

Hereinafter, such a coil part structure will be described. In designing various types of coils having a constant spacing, such as spiral coils and helical coils, it is necessary to derive a relational expression that can obtain the minimum loss resistance according to the number of turns of the coils, the radius of the leads, and the spacing between the leads.

28 is a cross-sectional view of a coil part structure in which a plurality of conductors having a circular cross section are arranged side by side at uniform intervals according to an embodiment of the present invention.

Referring to FIG. 28, N conductors having the same radius r ₀ are arranged uniformly along the distance P between the centers of the conductors. Such a structure may be formed by a spiral coil that is wound in a plurality of turns, a helical coil that is wound by a plurality of turns, or a structure in which parallel multiple straight conductors are disposed.

Figs. 29 to 32 illustrate, respectively, a coil portion or a lead wire structure capable of forming the cross-sectional structure shown in Fig. The cross sectional structure shown in Fig. 28 is a cross section from A1 to B1 of the spiral coil shown in Fig. 29, a cross section from A2 to B2 of the helical coil shown in Fig. 30, A3 And B3, respectively.

The circular spiral coil shown in Fig. 29 has a single conductor wire wound in several turns on a plane, but in the region AR1 including a predetermined area, for example, from A1 to B1, a plurality of conductor wires as shown in Fig. 28 They can be regarded as being arranged at uniform intervals. Here, the number of turns of the spiral coil corresponds to the number of the conductors in the predetermined area, and the interval between the centers of the conductors of the loops of the spiral coils may correspond to the interval between the centers of the conductors in the predetermined area AR1.

Similarly, in the helical coil shown in Fig. 30, although a single conductor is wound in several turns in the vertical direction, in a region AR2 including a predetermined region, for example, from A2 to B2, a plurality of conductors are arranged at uniform intervals Can be regarded as the same. Here, the number of turns of the helical coil corresponds to the number of the conductors in the predetermined region, and the distance between the centers of the conductors of the loops of the helical coil may correspond to the distance between the centers of the conductors in the predetermined region AR2.

In addition to the structures shown in Figs. 29 to 31, if any of the structures form a cross section as shown in Fig. 28 or a similar structure, the winding or arrangement method referred to in the present invention is applied.

For example, FIG. 32 is a plan view showing an example in which a structure according to FIG. 28 is applied to a rectangular spiral coil portion.

As shown in FIG. 32, the rectangular spiral coil is a single wire wound to form several rectangular loops in a horizontal plane, but in the region AR4 including a predetermined region, for example, from A4 to B4, It can be regarded as being the same as deployed. Here, the number of turns of the rectangular spiral coils corresponds to the number of the conductors in the predetermined area AR4, and the interval between the centers of the square loops of the rectangular spiral coils corresponds to the interval between the center lines of the conductors in the predetermined area AR4 have.

In the description with reference to FIG. 28, it is assumed that the illustrated cross-sectional structure is a cross-sectional structure of a coiled portion of the coiled coil with several turns, such as a spiral coil or a helical coil.

Referring again to FIG. 28, in the figure, P may mean a pitch between centers of conductors. For example, P may be the distance from the center of the first conductor to the center of the second conductor adjacent to the first conductor. In the embodiment of the present invention, the spacing between the conductors in the coil portion shown in Fig. 28 is even within a predetermined error range. That is, the P value between neighboring conductors included in the coil part is constant.

r ₀ represents the radius of the conductor. The radii of the conductors included in the coil section are the same. And N represents the number of conductors arranged in the corresponding area. For example, in a coil part such as a spiral coil or a helical coil, N may mean the number of turns of a wire wound. W represents the total width of the coil portion. For example, W may be the length from the end of the first conductor to the opposite end of the nth conductor when a total of N conductors are arranged from the first conductor to the nth conductor. For example, W is the width corresponding to the radius of the coil part in the plane in the case of the spiral coil, and may be the height at which the conductor is wound in case of the helical coil.

The same current flows through each conductor. At this time, the relational expression for obtaining the minimum resistance in the lead wire is as follows.

In Equation (12), r ₀ is the radius of the conductor, W is the total width of the coil portion, and N is the number of turns of the conductor (the number of conductors in the straight conductor arrangement structure). If r _0, W and r is _0, W and N is determined by the equation (12) in relation to N, the distance P between the central conductors may be determined by the following equation (13) of.

Using Equation (12) and Equation (13), it is possible to variously implement a coil portion that reduces the loss resistance of the wire and maximizes the intensity of the magnetic field in the wireless power transmission. For example, if the variables W and N are predetermined, the coil may be implemented to have an optimal radius r _o with a minimum resistance based on Equations (12) and (13). At this time, the distance p between the centers of the conductors can also be determined. Further, when W and r ₀ are predetermined, the number of turns N can be determined to have a minimum resistance. At this time, the interval P between the centers of the conductors is also determined.

The relational expression for obtaining the minimum resistance in the conductor illustrated in the equations (12) and (13) is applicable to all cases in which parallel multiple conductors are arranged or wound at even intervals in a predetermined area.

As mentioned above, in a structure including a plurality of conductors in which the same current flows, in order to obtain loss resistance, a magnetic field H generated by an adjacent conductor and affecting a target conductor must be obtained. Accordingly, in the present invention, a magnetic field generated in a coil structure in which a conductor is wound in several turns in a horizontal direction or a vertical direction, such as a spiral coil or a helical coil structure, and a magnetic field generated in a structure in which a plurality of parallel straight- The equality of equations (12) and (13) is possible.

FIG. 33 is an exemplary view for explaining magnetic field formation in a circular wire structure and an infinite straight wire. FIG. 33 (a) shows a magnetic field in a circular loop included in a spiral coil or a helical coil And Fig. 33 (b) shows the generation of the magnetic field in the infinite straight wire. D shown in Fig. 33 represents the distance from the center of the conductor, and Hz and Hρ represent the z-direction and ρ-direction magnetic fields respectively occurring at the D position. r1 means the distance from the center of the circular loop to the center of the conductor.

First, in order to determine whether the expressions (12) and (13) are applicable to the spiral coil structure in which a plurality of loops are wound in the horizontal direction, the absolute value of Hz | Hz at the D position of the inside loop shown in FIG. | And the | Hz | at the D position of the outside loop and the | Hz | at the D position of the infinite straight line shown in FIG. 33 (b) are similar to each other. In addition, to see if there is a magnetic field difference according to the change of r1, the cases where r1 was 2cm and 20cm were examined separately.

Fig. 34 is a graph showing the curves of | Hz | generated in accordance with the change of D in the inside and outside and the infinite straight line of the circular loop, respectively.

As shown in FIG. 34, it can be confirmed that | Hz | at the D position, which occurs in the inside, outside, and infinite straight conductors of the circular loop, are substantially equal to each other. Also, even if r1 is 2 cm or 20 cm, | Hz | It is almost the same. Therefore, the spiral coil structure can be applied to the above-described relational expressions, that is, equations (12) and (13), in the same manner as the infinite straight wire structure.

On the other hand, in order to determine whether the equations (12) and (13) are applicable to the helical coil structure in which a plurality of conductors are wound in the vertical direction, the absolute value | Hρ | of Hρ in the circular loop shown in FIG. The similarity is examined by comparing | H? | At the D position of the infinite straight line shown in FIG. 33 (b). In addition, to see if there is a magnetic field difference according to the change of r1, the cases where r1 is 5cm and 50cm are separately examined. FIG. 35 is a graph showing the curves of | Hρ | occurring in accordance with the change of D in the circular loop and the infinite straight wire.

As shown in Fig. 35, at the D position occurring in each of the circular loop and the infinite straight wire, H? Are almost the same. In addition, even when r1 is 5 cm or 50 cm, | Hρ | It is almost the same. Therefore, it can be understood that the above-described relational expressions, that is, Equation (12) and Equation (13), can be applied to the helical coil structure in the same manner as the infinite straight wire structure.

Equation (12) and Equation (13) are applicable to the spiral coil, the helical coil, and the plurality of infinite straight conductors shown in Figs. 29 to 31 if the cross section of a predetermined region is the same as that shown in Fig. It is possible.

As described above, the present invention provides a structure in which the spacing between centers of conductors is uniformly arranged in a structure in which a plurality of conductors are arranged side by side, such as a spiral coil or a helical coil, Respectively. Hereinafter, the reason for supporting the fact that the loss resistance generated in the lead wire has the smallest value when the distance between the centers of the lead wires is equal will be described.

36 is a graph for comparing the loss resistance generated when the distance between the centers of the conductor portions of the coil portion is equal and when the distances between the centers of the conductor portions are unequal, and the number of turns N of the conductor is 3 and 4, respectively.

In the simulation example shown in Fig. 36, it is assumed that the radius r0 of the conductor is 0.5 mm, the total width W of the coil portion is fixed, the length of each conductor is 1 meter, and the change in loss resistance . The conductors located at both ends of the coil section are fixed and the other conductors are moved by? P with respect to the distance P = 2 mm between the center of the conductor. When? P is 0, it means that the distance between the centers of the conductor portions of the coil portion is the same.

As shown in FIG. 36, as the frequency increases, the loss resistance increases as? P increases. That is, the loss resistance is the smallest when the conductors of the coil portion are arranged at regular intervals, and the loss resistance increases as the distance between the conductors approaches one of the conductors. Therefore, when the distance between the center lines of the conductors of the coil part is equal, it is possible to generate the magnetic field most efficiently in the case of wireless power transmission.

In addition, as described above, the embodiment of the present invention provides a structure in which a plurality of conductors having the same radius are arranged at even intervals, and moreover, in a coil part including such a structure, 12 and 13 illustrate the relationship between the parameters for minimizing the loss resistance caused by the contact resistance.

FIG. 37 shows the ratio of the radius of the conductor with which the loss resistance is minimized to the total width of the coil portion according to the number of turns N of the coil portion.

As shown in FIG. 37, the ratio r ₀ / W of the radius r _{0 of the} conductor to the total width W of the coil in the range where the number of turns N of the coil part is 2 or more and 1000 or less is given by the following expression All.

As shown in Equation (14), the ratio of the radius of the conductor to the total width of the coil is 0.001857 or more and 0.249923 or less. Considering the actual implementation margin, r ₀ / W can be set to 0.0018 to 0.25 in the range where the number of turns N of the coil part is 2 or more and less than 1000.

38 is a graph showing the curve of the loss resistance value per unit length of the number N of turns of the coil part according to the change of the ratio P / 2r ₀ of the distance P between the centers of the conductor lines and the conductor diameter 2r ₀ . In the measurement shown in FIG. 38, the interval P between the conductor lines was 2 mm, and r ₀ was set to be greater than 0.2 mm and smaller than 1 mm. That is, P / 2r ₀ is larger than 1 and smaller than 5.

38, the loss resistance is drastically decreased from P / 2r ₀ to 1 and the loss resistance is minimized when P / 2r ₀ is in the range of 1.3 to 1.9, except when the number of turns N is 2 to 3 And it shows an increasing tendency.

FIG. 39 shows a value of P / 2r ₀ to have the minimum loss resistance according to the number of turns N. FIG. As shown in FIG. 39, P / 2r ₀ having a minimum resistance has a value close to 1 only when N is 2 and N when 3 is 3, and N ranges from 1.2987 to 1.8182 from 4 and thereafter .

FIG. 40 is a graph showing the optimum (minimum) loss resistance per unit length according to the number of turns N, and FIG. 41 is a graph showing a value of P / 2r ₀ for the minimum loss resistance per unit length according to the number of turns N. Referring to FIGS. 39 to 40, when N is 2, the optimum loss resistance per unit length is 0.1743? / M, and then gradually increases to 0.4152? / M when N is 20. Referring to FIGS. 39 and 41, when the number of turns N is 2, P / 2r ₀ which has the minimum loss resistance is almost 1, but when N is 4, the value of P / 2r ₀ increases sharply, And has a constant value.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments of the present invention are not intended to limit the scope of the present invention but to limit the scope of the present invention. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents thereof should be construed as being included in the scope of the present invention.

Claims (29)

A transmitting apparatus for wireless power transmission,
A bowl-shaped transmitting device body; And
A transmitting coil part for wirelessly transmitting power to a receiving device based on power supplied from a power source,
The transmission coil unit includes:
A spiral coil part wound on a bottom surface of the transmission device body; And
And a helical coil portion wound on a side surface of the transmission device body so that a radius of the coil loop increases toward the upper portion. The method according to claim 1,
The radio power transmission device according to claim 1, wherein the helical coil portion extends from an end of the spiral coil portion and is wound. The method according to claim 1,
And the inclination of the helical coil is between 5 degrees and 90 degrees from the bottom surface. The method according to claim 1,
Wherein at least one of the spiral coil portion and the helical coil portion has a plurality of conductors having the same radius in a predetermined section wound at an equal interval within a predetermined error range. The method according to claim 1,
The transmission coil unit includes:
Wherein the receiving coil unit has a receiving coil unit that receives a radio wave from the receiving coil unit, the receiving coil unit being connected to the receiving coil unit, Transmitting apparatus. The method according to claim 1,
And a source coil part for receiving power from the power source and delivering the power to the transmission coil part. The method according to claim 6,
Further comprising at least one matching unit for adjusting impedance matching in the transmitting coil section according to a load of the receiving apparatus,
Wherein the matching unit comprises:
Further comprising: a transmit coil receiving power from the power source and transmitting the received power to the transmit coil section; and a source coil section independent of the transmit coil. The method according to claim 1,
The frequency of the transmitting coil part may be,
And adjusts it so as to be equal to the resonant frequency of the wireless power system including the wireless power transmission device and the reception device. The method according to claim 1,
And at least one capacitor is connected in series or parallel to the end of at least one of the spiral coil portion and the helical coil portion. The method according to claim 1,
Wherein at least one of the spiral coil portion and the helical coil portion is wound with one of a circular coil, a polygonal coil, and an elliptical coil. The method according to claim 1,
Wherein the spacing between the wires is determined based on the radius of the conductor, the total width of the coil portion, and the number of turns of the coil with respect to the plurality of conductors constituting the spiral coil portion and the helical coil portion. The method according to claim 1 or 11,
Wherein the spiral coil portion and the helical coil portion are wound such that the intervals between the loops are equally spaced. The method according to claim 1,
The transmitting device body includes:
A first case; And
And a second case coupled to the first case,
Wherein the spiral coil portion and the helical coil portion are formed between the first case and the second case,
Wherein the spiral coil portion is disposed below the bottom surface of the first case,
The helical coil part is wound along a side surface of the first case,
And the second case houses at least a portion of the spiral coil portion and the helical coil portion. 2. The apparatus of claim 1, wherein the spiral coil portion is powered from a first AC source, the helical coil portion is powered from a second AC source,
Further comprising a control unit for acquiring sensing data of the power received by the receiving device and controlling the output power of the first AC source and the second AC source based on the sensing data. 15. The apparatus of claim 14, wherein the control unit controls the spiral coil part and the helical coil part to supply more power to the coil part that transmits more power to the receiving device, or transmits less power to the receiving device To control the supply of a small amount of power to the coil load. 15. The wireless device of claim 14, wherein the control unit controls the first AC source and the second AC source to supply a predetermined power, Device. Bowl body;
A spiral coil part forming a magnetic field for supplying radio power from a bottom surface of the bowl body; And
And a helical coil part for supplying radio power from a side surface of the bowl body,
Wherein the spiral coil portion and the helical coil portion form a magnetic field for supplying radio power to a wider spatial region than when each of the spiral coil portion and the helical coil portion is individually provided. 18. The wireless power transmission device of claim 17, wherein the spiral coil portion is disposed on a bottom surface of the bowl body, and the helical coil portion is wound along a side surface of the bowl body, and the coil loop is wound so as to have a larger radius. A receiving apparatus for wireless power reception,
A bowl-shaped receiving device body; And
And a receiving coil part for receiving power supplied from the wireless power transmission device,
The receiving coil unit includes:
A spiral coil part wound on a bottom surface of the receiving device body; And
And a helical coil part wound on a side surface of the receiving device body so that a radius of the coil loop becomes larger toward the upper part. 20. The wireless power receiving apparatus according to claim 19, wherein the helical coil portion extends from an end of the spiral coil portion and is wound. 20. The receiver according to claim 19,
Further comprising at least one matching unit for adjusting an impedance matching in the receiving coil part according to a load of the receiving device,
Wherein the matching unit comprises:
Further comprising an impedance matching circuit constituting a parallel resonant circuit of a load of the receiving device and a receiving coil for receiving power from the transmitting coil part. A coil structure in a transmitting device or a receiving device for wireless power transmission,
A spiral coil part which is wound in a plane on a two-dimensional plane; And
And a helical coil portion wound in a vertical direction from the spiral coil portion, the helical coil portion being wound such that a radius of the coil loop becomes larger toward the upper portion. 23. The coil structure according to claim 22, wherein the helical coil portion extends from an end of the spiral coil portion and is wound. 23. The method of claim 22,
Wherein the helical coil part or the helical coil part includes a plurality of conductors having the same radius in a predetermined section and arranged at equal intervals within a predetermined error range,
Wherein a distance between centers of adjacent conductors is determined based on a skin effect generated in the conductor when a same current flows through the plurality of conductors and a loss resistance due to a proximity effect generated between adjacent conductors. 25. The method of claim 24,
Wherein a single lead wire is wound at a number of turns equal to the number of the plurality of lead wires in the predetermined section according to the even spacing. 25. The coil structure according to claim 24, wherein a distance between centers of the adjacent conductors is determined according to the following equation:
≪ Equation &
P = (W - 2r ₀ ) / (N-1)
Where P is the distance between the centers of the conductors, r ₀ is the radius of the conductor, W is the total width of the coil section, and N is the number of the conductors. The coil structure according to claim 24, wherein the ratio of the radius of the lead wire to the total width of the coil part is 0.0018 to 0.25. 25. The coil structure of claim 24, wherein a distance between the centers of adjacent conductors is determined based on a minimum resistance per unit length according to the number N of conductors. 25. The method of claim 24,
The radius of the conductor, the total width of the coil portion, and the number of conductors satisfy a condition according to the following equation,
≪ Equation &
r ₀ / w = αN ^β + γ
In the above formula, r0 represents the radius of the conductor, W represents the total width of the coil portion, and N represents the number of the conductors,? = 0.6534,? = -1.397,? = 0.001815.

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