KR101706372B1 - Wireless Power Transfer System Having Two-Phase Power Supply Unit - Google Patents

Abstract

Discloses a wireless power transmission system that is insensitive to a relative position between a power supply coil and a current collecting coil.
According to the present embodiment, there is provided a power supply apparatus including a current collector having a power feed unit including two sets of power feed coils for generating an electromagnetic field by an AC current, and a current collecting coil for receiving power from the power feed coils, Wherein the feeder coil has a feed region by winding a lead wire and the two sets of feed coils of the feeder portion include a first feed coil and a second feed coil.
According to this embodiment, by providing a phase difference of 90 degrees between the alternating currents applied to the first feeding coil and the second feeding coil, the effect of the position of the current collecting part on the power transmission is reduced and the radio transmission efficiency is improved.

Description

TECHNICAL FIELD [0001] The present invention relates to a wireless power transmission system having a two-phase drive type power supply unit,

The technical field to which this embodiment pertains is the transmission of wireless power.

The contents described in this section merely provide background information on the present embodiment and do not constitute the prior art.

A wireless power transmission system has been introduced for convenience and safety of electric power transmission of electric devices. The wireless power transmission system is advantageous in that it does not need to connect wires directly from the power supply side to the power supply side. Due to these advantages, a system for supplying electricity wirelessly to household appliances, office equipment, and electric vehicles has attracted considerable attention.

The wireless power transmission system is based on the principle of transformer. The power feeding device is installed outside and the electric power collecting device is installed inside the electric device to transfer and charge the electric power.

Fig. 1 (a) is a front view schematically showing a general power feeding coil and a current collecting coil, and Fig. 1 (b) is a plan view schematically showing a general power feeding coil and a current collecting coil.

 The power feeding coil 110 winds the wire to form a power feeding region, and the power collecting coil 120 winds the wire to form a current collecting area. When the relative positions of the power feeding coil 130 and the current collecting coil 140 are not properly aligned, the output voltage is lowered by the mismatch.

2 is a diagram showing output voltages according to relative positions of a general power supply coil and a current collecting coil. The width of the feeding coil and the current collecting coil is 25 cm, the width of the height between the feeding coil and the current collecting coil is 1/2, the current amount of the feeding coil and the current collecting coil is 12 and the current applied to the feeding coil is 40 A, The voltage is as shown in Fig.

Referring to FIG. 2, there is a problem in that efficiency is low because electric power must be transmitted in a state where the relative positions of the power supply side and the devices installed on the power collecting side do not coincide with each other. In particular, since the output voltage is rapidly changed according to the relative displacement of the power-feeding coil and the current-collecting coil, there is a problem that they must be used with good alignment.

Further, when the electric vehicle equipped with the wireless power transmission system is charged or parked in a designated place, there is a problem that the user must park or stop at a position aligned with the correct power supply side.

In addition, when an auxiliary device is installed to align the power supply coil and the current collecting coil in precise positions, there is a problem that the wireless power transmission system becomes bulky due to the auxiliary device or the internal space of the wireless power transmission system becomes insufficient.

The present invention has been made in order to solve such a problem, and it is an object of the present invention to provide a wireless power transmission system using a power supply coil and a current collecting coil configured to receive relatively little influence on the relative positions of a power supply coil and a current collector, There is a purpose.

According to an aspect of the present invention, there is provided a power supply apparatus including a power collecting unit including a power feed unit having two sets of power supply coils for generating an electromagnetic field by an AC current, and a power collecting coil for receiving power from the power feed coils, Wherein two sets of the power supply coils have a power supply region formed by winding wires, and the two sets of power supply coils include a first power supply coil and a second power supply coil.

The embodiment of the wireless power transmission system may further include one or more of the following features.

The number of the feed regions of the first feed coils may be m (m is a natural number), and the number of the feed regions of the second feed coils may be (m + 1).

The shape of the feed region of the first feed coils and the feed region of the second feed coils may be rectangular.

The power feeding region of the first feeding coil and the feeding region of the second feeding coil partially overlap with each other.

The feeding region of the first feeding coil and the feeding region of the second feeding coil may be positioned so as to overlap by 1/2 with respect to the area basis.

The direction of the winding of the conductive line constituting the feeding region of the first feeding coil may have the same current flow in the opposite direction to the outer conductor of the adjacent feeding region.

The direction of the winding of the conductive line constituting the feeding region of the second feeding coil may have the same current flow in the opposite direction to the outer conductor of the adjacent feeding region.

The phase difference between the alternating current of the first feeding coil and the alternating current of the second feeding coil may be 90 degrees.

According to another aspect of the present invention, there is provided a power supply apparatus including a power collecting unit having a power feed unit having a power feed coil for generating an electromagnetic field by an AC current and a power collecting coil for receiving power from the power feed coil, Wherein the current collecting coil of the current collecting portion has a current collecting region formed by winding a conductor and the current collecting region has the same shape as that of the power feeding region do.

The embodiment of the wireless power transmission system may further include one or more of the following features.

The shape of the power feeding region and the current collecting region may be rectangular.

The current collecting unit may include n current collecting coils (n is a natural number of 2 or more), and may be positioned so that the current collecting area of the current collecting coil is partially overlapped.

The current collecting part is composed of two sets of current collecting coils. The two sets of current collecting coils may be positioned so that the current collecting area is overlapped by 1/2 with respect to the area basis, and the phase difference of the voltages of the two sets of current collecting coils may be 90 degrees.

The current collecting part is composed of three sets of current collecting coils, and the current collecting coils are positioned so that the current collecting area is overlapped by 1/3 on an area basis, and the phase difference of voltages of the three sets of current collecting coils can be 120 degrees.

According to another aspect of the present invention, there is provided an electronic apparatus including: a first feeding coil for generating an electromagnetic field by an alternating current; a second feeding coil positioned in an electrically insulated state from the first feeding coil and generating an electromagnetic field by an alternating current; And a current collecting coil for receiving electric power from the second power feeding coil, wherein the first power feeding coil and the second power feeding coil have a power feeding region formed by winding a wire, .

The embodiment of the power-feeding coil set may further include one or more of the following features.

Wherein m is a natural number, m is a number of feeding regions of the first feeding coil, m is a natural number, m is a number of feeding regions of the second feeding coil, m is a number of feeding regions of the first feeding coil, Wherein the shape of the feed region of the feed coil is rectangular and the feed region of the first feed coil and the feed region of the second feed coil are overlapped by 1/2 with respect to the area basis, The phase difference of the alternating current of the second feeding coil may be 90 degrees.

According to another aspect of the present invention, there is provided a power supply apparatus including a power supply coil for generating an electromagnetic field by an alternating current, and a current collecting coil for receiving power from the power supply coil, wherein the power supply coil has a power supply region formed by winding a wire, The coil has a current collecting region formed by winding a wire, and the current collecting region has the same shape as the feeding region.

The embodiment of the power-feeding coil set may further include one or more of the following features.

The current collecting coil has n current collecting regions (n is a natural number of 2 or more), and the n current collecting regions may be partially overlapped.

According to another aspect of the present invention, there is provided a power supply system including a current collector having a power feeder having two sets of power supply coils for generating an electromagnetic field by an AC current, and a current collecting coil for receiving power from the power feeder coil, Wherein the power supply coil of the power supply unit includes a first power supply coil and a second power supply coil, the two sets of power supply coils of the power supply unit have a power supply region formed by winding a wire, And the current collecting region has the same shape as that of the power feeding region.

As described above, according to the embodiments of the present invention, by setting a phase difference of 90 between AC currents applied to the first feed coils and the second feed coils, the relative position of the feed parts and the current collectors affects power transmission Thereby improving the wireless transmission efficiency.

In addition, when the electric vehicle equipped with the wireless power transmission system is charged or parked in a designated place, it is possible to solve the inconvenience that the user has to park or stop at the correct position.

Further, since there is no need for an auxiliary device for aligning the power supply coil and the current collecting coil at precise positions, it is possible to utilize the space of the wireless power transmission system.

In addition, the power collecting area is partially overlapped, and each of the power collecting coils has the effect of extracting the same power to evenly distribute power of the power feeding coils.

Fig. 1 (a) is a front view schematically showing a general power feeding coil and a current collecting coil, and Fig. 1 (b) is a plan view schematically showing a general power feeding coil and a current collecting coil.
2 is a diagram showing output voltages according to relative positions of a general power supply coil and a current collecting coil.
FIG. 3 (a) is a front view showing a 1/2 feed coil and a current collecting coil according to an embodiment of the present invention, FIG. 3 (b) is a front view showing a feed area of a 1/2 feed coil according to an embodiment of the present invention (C) is a plan view showing a winding, a current direction, and a magnetic field direction of a 1/2 feed coil according to an embodiment of the present invention.
FIG. 4A is a front view showing a 2/3 power-feeding coil and a current-collecting coil according to another embodiment of the present invention, FIG. 4B is a front view of a 2/3 power-feeding coil according to another embodiment of the present invention, (C) is a plan view showing a winding, a current direction, and a magnetic field direction of the 2/3 power-supply coil according to another embodiment of the present invention.
5 (a) is a graph showing the magnetic flux density in the feeding region of the first feeding coil at t = 0 seconds according to an embodiment of the present invention, and FIG. 5 (b) = π / (2ω) second, the magnetic flux density in the feeding region of the first feeding coil is shown.
6A is a graph showing mutual inductance between a first feeding coil and a current collecting coil according to a relative position of a first feeding coil and a current collecting coil according to an embodiment of the present invention, FIG. 5 is a graph showing mutual inductance between the second feeding coil and the current-collecting coil according to the relative positions of the second feeding coil and the current-collecting coil according to the embodiment of FIG.
FIG. 7 is a graph showing an output voltage according to a relative position between a 1/2 power-feeding coil and a current-collecting coil according to an embodiment of the present invention.
8 (a) is a plan view schematically showing two sets of current collecting coils having a current collecting region, (b) schematically shows two sets of current collecting coils with a current collecting region partially overlapping according to an embodiment of the present invention (C) is a plan view showing windings of two sets of current-collecting coils according to an embodiment of the present invention.
9 is a graph showing induced electromotive force in two sets of current collecting coils according to another embodiment of the present invention.
10 (a) is a plan view schematically showing three sets of current collecting coils having a current collecting region, FIG. 10 (b) is a schematic view showing three sets of current collecting coils partially overlapping the current collecting region according to another embodiment of the present invention (C) is a plan view showing the windings of three sets of current-collecting coils according to another embodiment of the present invention.
11 is a graph showing induced electromotive force in three sets of current collecting coils according to another embodiment of the present invention.
Fig. 12A is a phaser diagram showing the voltage and current of the first feeding coil among two sets of feeding coils according to one current collecting coil, Fig. 12B is a view showing the voltage and current of the first feeding coil among two sets of feeding coils according to one current collecting coil, 2 is a phasor diagram showing the voltage and current of the power-feeding coil, and (c) is a phasor diagram showing the voltage and current of one current-collecting coil.
13 is a view showing a voltage and a current of a first feed coil among two sets of feed coils according to two sets of current collecting coils according to another embodiment of the present invention.
FIG. 14A is a phaser diagram showing voltage and current of a first feed coil among two sets of feed coils according to two sets of current collecting coils according to another embodiment of the present invention, and FIG. FIG. 5 is a diagram showing voltage and current of a second feed coil among two sets of feed coils according to two sets of current collecting coils according to another embodiment; FIG.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals whenever possible, even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. Throughout the specification, when an element is referred to as being "comprising" or "comprising", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise . In addition, '... Quot ;, " module ", and " module " refer to a unit for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software.

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.

First, referring to FIG. 3, two sets of power supply coils, which are one embodiment of the present invention, will be described.

In the present embodiment, the wireless power transmission system includes a power feed unit having two sets of power feed coils 340 and 350 for generating an electromagnetic field by an AC current, and a power collecting unit having power collecting coils receiving power from the power feed coils . The power transmission is achieved by electromagnetic induction or magnetic resonance.

The feed region means an inner region of a physical space formed by winding a lead wire constituting a feed coil, and the current collecting region means an inner region of a physical space formed by winding a lead wire serving as a current collecting coil.

The two feeding coils of the feeding part are formed by the first feeding coil 340 and the second feeding coil 350. The number of feeding regions of the first feeding coil is m (m is a natural number), and the number of feeding regions of the second feeding coil is (m + 1). That is, the feed regions of two sets of the power supply coils can be formed into an arbitrary m / (m + 1) configuration such as a 1/2 configuration and a 2/3 configuration. Since the electric vehicle is charged by parking or stopping, the number of the feeding regions is limited to m and (m + 1) and is formed in the feeding coil.

Hereinafter, two sets of the power supply coils having the feed region of m / (m + 1) will be described in detail. That is, some overlapping of the feeding region of the first feeding coil and the feeding region of the second feeding coil will be described.

Two sets of feed coils with a feed region of 1 / configuration are called 1/2 feed coils.

FIG. 3 (a) is a front view showing a 1/2 feed coil and a current collecting coil according to an embodiment of the present invention, FIG. 3 (b) is a front view showing a feed area of a 1/2 feed coil according to an embodiment of the present invention Fig.

As shown in Fig. 3 (a), the 1/2 feeding coil 302 and the current-collecting coil 301 are located at a certain distance. The first feeding coil and the second feeding coil are positioned such that the feeding region 310 of the first feeding coil and the feeding regions 320 and 330 of the second feeding coil partially overlap each other in the 1/2 feeding coil 302. [ The shape of the power feeding region 310 of the first power feeding coil and the power feeding regions 320 and 330 of the second power feeding coil are rectangular and the power feeding region 310 of the first power feeding coil and the power feeding regions 320 and 330 ) Can be positioned so as to overlap by 1/2 with respect to the area basis.

FIG. 4A is a front view showing a 2/3 power-feeding coil and a current-collecting coil according to another embodiment of the present invention, FIG. 4B is a front view of a 2/3 power-feeding coil according to another embodiment of the present invention, Fig.

As shown in Fig. 4 (a), the 2/3 feeder coil 402 and the current collector coil 401 are located at a certain distance. The first feeding coil and the second feeding coil are formed so as to partially overlap the feeding regions 410 and 420 of the first feeding coil and the feeding regions 430, 440 and 450 of the second feeding coil in the 2/3 feeding coil 402, . The feed regions 410 and 420 of the first feed coils and the feed regions 430 and 440 and 450 of the second feed coils are rectangular and have a shape in which the feed regions 410 and 420 of the first feed coils and the second feed coils The power supply regions 430, 440 and 450 may be positioned so as to overlap by 1/2 with respect to the area basis.

3B and 5B, the shape of the power supply region is shown as a rectangle, but it may also be a square, a polygon, a circle, or the like.

Hereinafter, the winding direction and the current direction of the power supply coil will be described.

FIG. 3 (c) is a plan view showing the winding, the current direction, and the magnetic field direction of the 1/2 feed coil according to the embodiment of the present invention.

The direction of winding of the conductor forming the feed regions 310, 320, 330 of the first feeding coil and the second feeding coil in the 1/2 feeding coil 302 is such that the same current flows in the opposite direction to the outer conductor of the adjacent feeding region . Considering that the induced electromotive force is proportional to the turns, the turns of the leads can be one or more than two. Since the currents of the first feeding coil 340 and the second feeding coil 350 flow in respective conductors, they are electrically isolated from each other.

The direction of the current flowing through the conductor 311 forming the power supply region 310 in the first feeder coil 340 may be clockwise, as shown in Fig. 3 (c).

When the current flowing in the wire 321 forming the first feeding region 320 from the left side of the second feeding coil 350 flows clockwise in the same manner as the first feeding coil 340, The current flowing in the conductor 331 forming the second power supply region 330 from the left side flows in a counterclockwise direction. This is because the direction of the current flowing through the coil determines the direction of the magnetic field.

It is apparent that currents flowing through the conductors 311 and 321 forming the first feed regions 310 and 320 from the left side of the first feeder coil 340 and the second feeder coil 350 can flow counterclockwise .

4C is a plan view showing a winding, a current direction, and a magnetic field direction of the 2/3 power-supply coil according to another embodiment of the present invention.

The direction of winding of the conductor forming the feed regions 410, 420, 430, 440 and 450 of the first feed coil and the second feed coil in the 2/3 feed coil 402 is the same as that in the outer conductor of the adjacent feed region So as to have a flow in the opposite direction. Considering that the induced electromotive force is proportional to the turns, the turns of the leads can be one or more than two. Since the currents of the first feeding coil 460 and the second feeding coil 470 flow in the respective conductors, they are electrically isolated from each other.

When a current flowing in the conductor 411 forming the first feed region 410 from the left side of the first feed coil 460 flows in the clockwise direction as shown in FIG. 4C, The winding of the second power supply region 460 connects the current flowing in the conductor 421 forming the second power supply region 420 from the left side so as to flow in the counterclockwise direction. This is because the direction of the current flowing through the coil determines the direction of the magnetic field.

When the current flowing in the conductor 431 forming the first feeding region 430 from the left side of the second feeding coil 470 flows clockwise in the same manner as the first feeding coil 460, The current flowing in the conductor 441 forming the second power supply region 440 from the left side flows in the counterclockwise direction and the current flowing in the conductor 451 forming the third power supply region 450 from the left side flows Connect the current so that it flows clockwise.

The currents flowing through the conductors 411 and 431 forming the first feed regions 410 and 430 from the left side of the first feed coils 460 and the second feed coils 470 in the 2/3 feed coil 402 are half It is obvious that it may flow clockwise.

The above-described 1/2 feed coil and 2/3 feed coil are merely one embodiment, and can make two sets of feed coils having an m / (m + 1) configuration with the number and shape of various feed zones.

Hereinafter, the current flowing in the feed coil and the direction of the magnetic field will be described.

A magnetic field is formed when electric current flows through the conductor. The direction and intensity of the magnetic field formed around the current-carrying conductors (straight conductors, round conductors, solenoids) follow the Amper's law.

Referring to FIG. 3 (c), the feeder coil 311 and the feeders 311 and 312 forming the first feed regions 310 and 320 from the left side of the first feeder coil 340 and the second feeder coil 350, respectively, The direction of the magnetic field 312 in the feeding region 310 of the first feeding coil 340 becomes the direction of entering the sheet surface and the left direction of the second feeding coil 350 The direction of the magnetic field 322 in the first feeding region 320 is the direction going into the ground and the direction of the magnetic field 332 in the second feeding region 330 from the left side of the second feeding coil 350 is from the ground It is the direction coming out.

Referring to FIG. 4C, the 2/3 feeder coil includes a first feeder coil 460 and a second feeder coil 470. The feeder 411 forms the first feeder regions 410 and 430 from the left side of the first feeder coil 460 and the second feeder coil 470, The direction of the magnetic field 412 in the first feeding region 410 from the left side of the first feeding coil 460 becomes the direction of entering the sheet surface and the direction of the first feeding coil The direction of the magnetic field 422 in the second feed region 420 from the left side of the second feed coil 470 is the direction coming from the ground and the direction of the magnetic field 432 in the first feed region 430 from the left side of the second feed coil 470 The direction of the magnetic field 442 in the second feeding region 440 from the left side of the second feeding coil 470 is the direction coming from the sheet surface and the left side of the second feeding coil 470 The direction of the magnetic field 452 inside the third feed region 450 is the direction of entering the ground .

In order to prevent the magnetic fields of the two sets of the power supply coils from affecting each other, the power supply coils form a power supply region of m / (m + 1).

The influence of the magnetic field in the feeding region of the first feeding coil of the 2/3 feeding coil on the magnetic field in the feeding region of the second feeding coil is as follows. The first feeding region 410 is formed from the left side of the first feeding coil 460, The internal magnetic field 412 and the magnetic field 422 inside the second feed region 420 affect the magnetic field 442 inside the second feed region 440 from the left side of the second feed coil 470 in the opposite direction It is canceled. The influence of the magnetic field 412 in the first feeding region 410 from the left side of the first feeding coil 460 on the magnetic field 432 inside the first feeding region 430 from the left side of the second feeding coil 470 The magnetic field 422 inside the second feed region 420 from the left side of the first feed coil 460 is shifted from the left side of the second feed coil 470 to the magnetic field 452 inside the third feed region 450 They are counterproductive and counterproductive.

Likewise, the influence of each magnetic field in the feed region of the second feed coils of the 2/3 feed coils on the magnetic field in the feed region of the first feed coils is canceled each other.

Hereinafter, the relationship between the relative positions of the feed coils and the current collecting coils and the phase angles of the currents will be described. The phases of the alternating current of the first feeding coil and the alternating current of the second feeding coil may be different from each other. However, in consideration of the transmission efficiency, the phase difference between the alternating current of the first feeding coil and the alternating current of the second feeding coil is preferably 90 degrees.

The magnetic flux density according to the current depends on the size, shape and winding number of the coil. The magnetic flux density [Wb / m2] at a distance h [m] from the center of the coil once wound once when the radius of the coil is b [m] and the current flowing is I [A]

5 (a) is a graph showing the magnetic flux density in the feeding region of the first feeding coil at t = 0 seconds according to an embodiment of the present invention, and FIG. 5 (b) = π / (2ω) second, the magnetic flux density in the feeding region of the first feeding coil is shown.

이고 단위는 radian이 된다. 세로축은 자속밀도를 나타내고 단위는 Wb/m²이 된다. 5 (a) and 5 (b), x represents the relative position of the current-collecting coil with respect to the leftmost side of the first feeding coil. w means one side of the rectangle of the feeding area, i.e., width. The horizontal axis is x, the unit is m, or the horizontal axis is

And the unit is radian. The vertical axis represents the magnetic flux density and the unit is Wb / m ² .

)이 πx/w만큼 지연된다. 즉 기계적인 상대위치 x에 따른 전기각(

)은 πx/w에 상당하게 된다.Referring to Figures 5 (a) and 5 (b), the magnetic flux appears to move to the left by w for half a period of current. Therefore, if the current-collecting coil is moved to the right by x from the leftmost side,

) Is delayed by? X / w. That is, the electrical angle (x

) Corresponds to? X / w.

)으로 2π에 해당한다는 것을 의미하고 x=2w인 곳의 자속은 x=0인 곳의 자속과 같다는 것을 의미하므로, 급전코일과 집전코일의 상대위치와 전류의 위상각의 관계는 수학식 2와 같이 표현될 수 있다. Therefore, 2π / w means that the distance 2w away is the electrical angle (

) Means that the magnetic flux at x = 2w is equal to the flux at x = 0, so the relationship between the relative position of the feed coils and the current collecting coil and the phase angle of the current is expressed by Equation 2 Can be expressed as.

)으로 나타낼 수 있고, 이는 π와 급전영역의 직사각형의 한 변, 즉 폭을 의미하는 w로 표현된다.Referring to Equation (2), the mechanical relative position x of the current-collecting coil with respect to the leftmost side of the first feeding coil is an electrical angle

), Which is represented by w, which means one side of a rectangle of the feeding region, that is, the width.

Hereinafter, the constant output voltage of the current-collecting coil will be described in detail.

When a current having a phase difference of 90 degrees flows through two sets of the power supply coils, the current i2a flowing through the first feeding coil is expressed by Equation (3) and the current i2b flowing through the second feeding coil is expressed by Equation (4).

Equations (3) and (4) are expressed by a sinusoidal function whose magnitude is Im and have a phase difference of 90 degrees.

The mutual inductance between the first feeding coil and the current collecting coil according to the relative positions of the first feeding coil and the current collecting coil is expressed by Equation (5). Although there is an error between both sides of the feed region and the current collection region, the closer to the center of the feed region and the current collection region, the closer to Equation (5).

Equation (5) is expressed by a sinusoidal function whose magnitude is M _pickup .

The M _pickup is a mutual inductance when the first feeding coil forming the first feeding region from the left side of the first feeding coil coincides in position with the current collecting coil. The M _pickup in the 1/2 feeding coil is a mutual inductance when the first feeding coil forming the first feeding region 310 from the left side of the first feeding coil 340 and the current collecting coils are aligned in position, The M _pickup in the coil is a mutual inductance when the first feeding coil forming the first feeding region 410 from the left side of the first feeding coil 460 coincides with the current collecting coil in position.

M _aL is a mutual inductance between the power-feeding coil and the current-collecting coil, which _constitute the feeding region on the leftmost side of the first feeding coil. In the 1/2 feeding coil M _aL is the mutual inductance between the feeding coil and the current collecting coil forming the feeding region 310 on the leftmost side of the first feeding coil 340, and in the 2/3 feeding coil M _aL is the first feeding And the mutual inductance between the power supply coil and the current-collecting coil constituting the power supply region 410 on the leftmost side of the coil 460.

FIG. 6A is a graph showing a mutual inductance between the first feeding coil and the current-collecting coil according to the relative positions of the first feeding coil and the current-collecting coil according to the embodiment of the present invention. That is, FIG. 6 (a) is a graph showing the equation (5). The graph is represented by a sinusoidal function with the horizontal axis x, the period 2π / w, the vertical axis M _aL, and the magnitude M _pickup .

The mutual inductance between the second feed coils and the current collecting coil according to the relative positions of the second feed coils and the current collecting coil is expressed by Equation (6).

Equation (6) is expressed by a sinusoidal function whose magnitude is M _pickup .

M _bL is the mutual inductance between the power supply coil and the current collecting coil that is w / 2 away from the power supply coil forming the power supply region on the leftmost side of the first power supply coil to the right. That is, the mutual inductance between the power supply coil and the current collecting coil that forms the second feed region 330, 440 from the leftmost side of the second feed coils 350, 470. In the 1/2 feeding coil, M _bL is the mutual inductance between the power feeding coil and the current collecting coil that forms the second feeding region 330 from the leftmost side of the second feeding coil 350. In the 2/3 feeding coil, M _bL is the mutual inductance between the feeding coil and the current collecting coil that forms the second feeding region 440 from the leftmost side of the second feeding coil 470.

6 (b) is a graph showing the mutual inductance between the second feeding coil and the current-collecting coil according to the relative positions of the second feeding coil and the current-collecting coil according to the embodiment of the present invention. That is, FIG. 6 (b) is a graph showing the equation (6). In the graph, the horizontal axis is x, the period is 2π / w, the vertical axis is M _bL, and the magnitude is expressed as a sinusoidal function with M _pickup .

The relationship between the phasor I _2a of the current i _2a flowing in the first feeding coil and the phasor I _2b of the current i _2b flowing in the second feeding coil expressed in the equation (4) expressed in the equation (3) is expressed by the following equation (7).

V _pickup is the voltage induced in the current collecting coil, and V _pickup is expressed by Equation (8).

로 일정하고 상대위치 x에 따라 유도전압의 위상만 바뀐다. 즉, 상대위치에 상관없이 전압크기가 일정하여 전송효율을 극대화시키는 효과가 있다.Therefore, when the first feeding coils 340 and 460 and the second feeding coils 350 and 470 are positioned apart by w / 2, if the current I _2a and the current I _2b flow in phase difference of 90 degrees, Regardless of location x

And the phase of the induced voltage changes according to the relative position x. That is, the voltage magnitude is constant regardless of the relative position, thereby maximizing the transmission efficiency.

FIG. 7 is a graph showing an output voltage according to a relative position between a 1/2 power-feeding coil and a current-collecting coil according to an embodiment of the present invention.

Referring to FIG. 7, the width of the power supply coil and the current collector coil is 25 cm, and the height of the feeder coil and the current collector coil is 1/2 of the height of the current collector coil. , Dcl can see 25cm from 0cm to 25cm. The output voltage of the current-collecting coil is kept constant in the position interval of Dc1.

Fig. 7 shows the output voltage of the current-collecting coil when it is a half current-collecting coil, and Dcl shows a section where the output voltage is constant. Dcl is doubled for 2/3 current collectors. Therefore, Dcl is given as the product of the length of one side of the feeding coil and the current collecting coil and m.

A predetermined magnetic field is formed by partially overlapping the feed region of the first feed coils and the feed region of the second feed coils in two sets of the feed coils. As shown in FIG. 3 (b), the 1/2 feed coil partially overlaps the feed regions 310 of the first feed coils 340 and the feed regions 320 and 330 of the second feed coils 350 The second feed coils are formed in the feed regions 410 and 420 of the first feed coils 460 and the feed regions 410 and 420 of the second feed coils 470 as shown in FIG. 430, 440, and 450 are partially overlapped to form a constant magnetic field. Since a constant magnetic field is formed in the position interval as Dcl, the output voltage of the current-collecting coil can be kept constant at the position of Dcl.

Hereinafter, n sets of current-collecting coils, which is another embodiment of the present invention, will be described.

In the present embodiment, the wireless power transmission system includes a power supply unit having a power supply coil for generating an electromagnetic field by an AC current, and a current collector having a current collector for receiving power from the power supply coil. The current collecting coil of the current collector winds the lead wire to have a current collecting area, and the current collecting area has the same shape as the feeding area of the power feeding coil.

The whole house can be made up of one set of collecting coils. The whole of the current collector can be made of a set of n (n is a natural number of 2 or more) current collecting coil, and the current collecting area of the current collecting coil can be partially overlapped. Since the currents of the n sets of the current-collecting coils flow in the respective current-collecting coils, they are electrically isolated from each other. Considering that the induced electromotive force is proportional to the turns, the turns of the lead of the current collecting coil may be one or more than two.

Hereinafter, two sets of the current collecting coils will be described in more detail.

8 (a) is a plan view schematically showing two sets of current collecting coils having a current collecting region, (b) schematically shows two sets of current collecting coils with a current collecting region partially overlapping according to an embodiment of the present invention (C) is a plan view showing windings of two sets of current-collecting coils according to an embodiment of the present invention.

In the present embodiment, the current collecting portion of the wireless power transmission system is composed of two sets of current collecting coils. The current collecting regions 830 and 840 of the current collecting coils 810 and 820 are rectangular in shape and the current collecting regions 830 and 840 are As shown in FIG. Thus, a two-phase voltage having a phase difference of 90 degrees is generated in the two sets of the current collecting coils 850 and 860. Each of the current-collecting coils 850 and 860 derives the same power to evenly distribute the power of the power-feeding coils.

Assuming that the induced electromotive forces in the two sets of the current collecting coils 850 and 860 are V _R and V _S , V _R is expressed as shown in Equation (9), and V _S is expressed as shown in Equation (10).

Among the induced electromotive forces of the two sets of current collecting coils, V _R is the induced electromotive force in the current collecting coil 850 coinciding with the position of the power feeding coils. And V _S is the induced electromotive force in the current collector coil 860 located at a distance of w / 2 from the power supply coil. The relative position w / 2 corresponds to an electrical angle of 90 degrees.

이다. 전기각 90도는 상대위치 w/2에 매치하게 된다.9 is a graph showing induced electromotive force in two sets of current collecting coils according to another embodiment of the present invention. 9 is a graph showing Equations (9) and (10). The graph horizontal axis ωt and period 2π and a vertical axis V _R and V s magnitude is represented by a sinusoidal function Vm. Vm is

to be. The electrical angle of 90 degrees will match the relative position w / 2.

Therefore, the current collecting regions 830 and 840 of the two sets of current collecting coils are partially overlapped, and each of the current collecting coils 850 and 860 has an effect of generating a two-phase voltage having a phase difference of 90 degrees.

Hereinafter, the three sets of current-collecting coils will be described in more detail.

10 (a) is a plan view schematically showing three sets of current collecting coils having current collecting regions, and FIG. 10 (b) schematically shows three sets of current collecting coils partially overlapping the current collecting region according to an embodiment of the present invention. (C) is a plan view showing a winding of three sets of current-collecting coils according to an embodiment of the present invention.

In this embodiment, the current collecting portion of the wireless power transmission system is composed of three sets of current collecting coils, and the current collecting regions 1040, 1050 and 1060 of the current collecting coils 1010, 1020 and 1030 are rectangular and the current collecting regions 1040 and 1050 , 1060) are overlapped by 1/3 on an area basis. Thus, a three-phase voltage having a phase difference of 120 degrees is generated in the three sets of the current collecting coils 1070, 1080 and 1090. Each of the current collecting coils 1070, 1080, and 1090 derives the same power to evenly distribute the power of the power supply coil.

Let V _R , V _S , and V _T be the induced electromotive forces in the three sets of current collecting coils 850 and 860, V _R is expressed by Equation (9), V _S is expressed by Equation , V _T is expressed as shown in Equation (12).

Among the induced electromotive forces of the three sets of current collecting coils, V _R is the induced electromotive force in the current collecting coil 850 coinciding with the position of the power feeding coil. And V _S is the induced electromotive force in the current collector coil 860 located at a distance of 2 w / 3 from the feed coil. Relative position 2w / 3 corresponds to electrical angle of 60 degrees. V _T is the induced electromotive force in the current collector coil 860 located at a distance of w / 3 from the feed coil. V _T is the difference of 180 degrees in the relation with V _R by changing the terminal of the winding again and making 180 degrees difference.

이다. 전기각 120도는 상대위치 2w/3에 매치하게 된다.11 is a graph showing induced electromotive force in three sets of current collecting coils according to another embodiment of the present invention. 11 is a graph showing Equations (9), (11), and (12). In the graph, the horizontal axis is ωt, the period is 2π, and the vertical axis is V _R , V s, V _T and the magnitude is V m . Vm is

to be. The electrical angle of 120 degrees will match the relative position 2w / 3.

Accordingly, the current collecting regions 1040, 1050, and 1060 of the three sets of the current collecting coils are partially overlapped, and each of the current collecting coils 1070, 1080, and 1090 has an effect of generating a three-phase voltage having a phase difference of 120 degrees.

8 (b) and 10 (b), although the shape of the current collecting region is shown as a rectangle, it may be a square, a polygon, or a circle. The one, two, or three sets of the current collecting coil exemplified above are only one embodiment and can be constituted of n sets of current collecting coils.

Hereinafter, the effect of the n sets of the power collecting coils to evenly distribute the power of the power supply coils will be described in detail.

만큼 이동된 위치에 있고, 집전코일에 연결된 부하를 저항이라 가정한 경우 즉 집전코일의 전압과 전류가 동상이라면, 제1급전코일의 전압은 수학식 13과 같이 표현되고, 제2급전코일의 전압은 수학식 14와 같이 표현된다.The phase of the voltage of the current-collecting coil is determined by the position of the current-collecting coil. The position of the current-collecting coil is shifted from the leftmost side of the first feeding coil to the electric angle of the two sets of the feeding coils

The voltage of the first feeding coil is expressed by Equation (13), and the voltage of the second feeding coil is expressed by Equation (13), and the voltage of the second feeding coil Is expressed by Equation (14).

Equations (13) and (14) mean the phasor voltage.

The voltage generated in the power supply coil and the current-collecting coil and the current flowing therethrough are represented by phasers as shown in FIG.

FIG. 12 (a) is a diagram showing voltage and current of the first feeding coil among two sets of feeding coils according to one current collecting coil. FIG. V _2a represents the voltage of the first feeding coil, and I _2a represents the current of the first feeding coil. FIG. 12 (b) is a diagram showing voltage and current of the second feeding coil among two sets of feeding coils according to one current collecting coil. V _2b represents the voltage of the second feeding coil, and I _2b represents the current of the second feeding coil. FIG. 12C is a view showing a voltage and a current of one current-collecting coil. V _pickup represents the voltage of the current collecting coil, and I _pickup represents the current of the current collecting coil.

에 따라 원주상을 이동한다. V _2a는 중심이 I_2a상에 위치한 원, V _2b는 중심이 I _2b상에 위치한 원의 원주상에 그려진다. 2세트의 급전코일에서 전압과 전류는 동상이 아니고 2세트의 급전코일에서는 전류가 전압보다 위상이 빨라 하드스위칭이 되고 2세트의 급전코일이 분담하는 전력이 균등하지 못하게 되는 문제점이 있다.As shown in Figs. 12 (a) and 12 (b), the voltage phasers of two sets of power supply coils are positioned

As shown in FIG. V _2a is a circle whose center is on I _2a , and V _2b is drawn on the circle of a circle whose center is located on I _2b . In the two sets of power supply coils, voltage and current are not in phase, and in the case of two sets of power supply coils, the current is faster than the voltage, resulting in hard switching, and the power shared by the two sets of power supply coils becomes uneven.

On the other hand, there are two sets of current collecting coils on the current collecting side. One current collecting coil is referred to as X and another current collecting coil is referred to as Y for the sake of explanation. Assuming that the current-collecting coil Y is located in a space corresponding to 90 degrees to the right of the current-collecting coil X, the inductance of two sets of current-collecting coils on the current-collecting side and the first power- 15 and 16, respectively.

Equations (15) and (16) are expressed by a sinusoidal function whose magnitude is M _pickup and have a phase difference of 90 degrees.

V _{2a, which} is the voltage induced in the first feeding coil, is expressed by Equation (17).

Equation (17) means the phasor voltage. The first term of Equation (17) is expressed by Equation (18) as V _2aX , and the second term of Equation (17) is expressed by Equation (19) as V _2aY . And Equations 18 and 19 mean the phasor voltage.

The voltage generated in the power supply coil by two sets of the current collecting coils X and Y can be expressed as shown in FIG.

13 is a view showing a voltage and a current of a first feed coil among two sets of feed coils according to two sets of current collecting coils according to another embodiment of the present invention.

As shown in FIG. 13, when the two voltages V _2aX and V _2aY are _combined , the voltage becomes in phase with the current. The payload of voltage and current generated in two sets of power supply coils is shown in Fig.

FIG. 14A is a phaser diagram showing voltage and current of a first feed coil among two sets of feed coils according to two sets of current collecting coils according to another embodiment of the present invention, and FIG. FIG. 5 is a diagram showing voltage and current of a second feed coil among two sets of feed coils according to two sets of current collecting coils according to another embodiment; FIG.

In the two sets of power supply coils, voltage and current are in phase, and in two sets of power supply coils, soft switching is achieved in which loss and noise are reduced, and the power shared by two sets of power supply coils is equalized.

The foregoing description is merely illustrative of the technical idea of the present embodiment, and various modifications and changes may be made to those skilled in the art without departing from the essential characteristics of the embodiments. Therefore, the present embodiments are to be construed as illustrative rather than restrictive, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The scope of protection of the present embodiment 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.

110, 130: power supply coil
120, 140, 301, 401: current collecting coil
302: 1/2 feeding coil
402: 2/3 power supply coil
310, 320, 330, 410, 420, 430, 440, 450:
311, 321, 331, 411, 421, 431, 441, 451:
312, 322, 332, 412, 422, 432, 442, 452:
340, 460: a first feeding coil
350, 470: a second feeding coil
810, 820, 850, 860, 1010, 1020, 1030, 1070, 1080, 1090:
830, 840, 1040, 1050, 1060: current collecting area

Claims (6)

A first feeding coil having m feeding regions formed by winding wires (m is a natural number); And
(M + 1) number of feed regions formed by winding the wires,
/ RTI >
Wherein the first feed coil and the second feed coil generate an electromagnetic field by an alternating current and the winding direction of the conductor constituting the feed region of the first feed coil and the feed region of the second feed coil is located outside the adjacent feed region Wherein the first feed coil and the second feed coil are arranged such that the same current flows in the opposite direction and the feed region of the first feed coil and the feed region of the second feed coil overlap by 1/2 with respect to the area, And the phase difference between the current and the alternating current of the second feeding coil is 90 degrees. The method according to claim 1,
Wherein the shape of the feeding region of the first feeding coil and the feeding region of the second feeding coil is a rectangle. 1. A wireless power transmission system comprising a power supply coil set and a power collection coil set,
The power supply coil set includes:
A first feeding coil having m (m is a natural number) feeding regions formed by winding a wire, and
And a second feed coil having (m + 1) feed regions formed by winding wires, wherein the first feed coils and the second feed coils generate an electromagnetic field by an alternating current, and the first feed coils The feed direction of the first feed coils and the feed direction of the second feed coils are set so that the same current flows in the opposite direction to the outer lead of the adjacent feed region, The phase difference of the alternating current of the first feeding coil and the alternating current of the second feeding coil is 90 degrees,
Wherein the current-
And a second current-collecting coil having a first current-collecting coil having a current-collecting region formed by winding a wire and a current-collecting region formed by winding a wire, wherein the first current-collecting coil and the second current- And a current collecting region of the first current collecting coil and a current collecting region of the second current collecting coil are overlapped with each other by an area based on the induced voltage of the first current collecting coil and the induced voltage of the second current collecting coil, The phase difference of 90 degrees
Wherein the wireless power transmission system comprises: The method of claim 3,
Wherein the shape of the power feeding region and the power collecting region is a rectangle. 1. A wireless power transmission system comprising a power supply coil set and a power collection coil set,
The power supply coil set includes:
A first feeding coil having m (m is a natural number) feeding regions formed by winding a wire, and
And a second feed coil having (m + 1) feed regions formed by winding wires, wherein the first feed coils and the second feed coils generate an electromagnetic field by an alternating current, and the first feed coils The feed direction of the first feed coils and the feed direction of the second feed coils are set so that the same current flows in the opposite direction to the outer lead of the adjacent feed region, The phase difference of the alternating current of the first feeding coil and the alternating current of the second feeding coil is 90 degrees,
Wherein the current-
A first current collecting coil having a current collecting region formed by winding a conductor, a second current collecting coil having a current collecting region formed by winding a conductor, and a third current collecting coil having a current collecting region formed by winding a conductor, , The second current-collecting coil, and the third current-collecting coil receive electric power from the power-feed coils, and the current-collecting region of the first current-collecting coil, the current-collecting region of the second current- And the phase difference between the induced voltage of the first current collector coil, the induced voltage of the second current collector coil, and the induced voltage of the third current collector coil is 120 degrees
Wherein the wireless power transmission system comprises: 6. The method of claim 5,
Wherein the shape of the power feeding region and the power collecting region is a rectangle.

Images