JP2014087125A - Non-contact power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain practically sufficiently high transmission efficiency without using angle compensation means because of large likelihood in a relative angle between a power transmission resonance coil and a power reception resonance coil against constraint of reduction in transmission efficiency.SOLUTION: Provided is a non-contact power transmission device for transmitting power from a transmitting device to a receiving device via magnetic resonance between a power transmission resonance coil and a power reception resonance coil, the non-contact power transmission device comprising: a power transmission device 1 having a power transmission coil unit 3 including a power transmission resonance coil 3b and a power receiving device 2 having a power reception coil unit 4 including a power reception resonance coil 4b. Either the power transmission resonance coil or the power reception resonance coil has a three-dimensionally bent or curved shape, and the other resonance coil has a planar shape. The resonance coil of three-dimensional shape is configured so that there exist at least three partially flat regions defined by a bent or curved portion of the coil winding, the plane of each of the partially flat regions having respectively different directions relative to the plane of the resonance coil of planar shape.

Description

  The present invention relates to a non-contact power transmission apparatus that transmits power in a non-contact (wireless) manner through an interaction between a power transmission coil and a power reception coil.

  Non-contact power transmission methods include electromagnetic induction using electromagnetic induction (several hundreds of kHz or less), electric / magnetic resonance using LC-resonant transmission via electric field or magnetic resonance, and microwave transmission using radio waves (several GHz). Alternatively, a laser power transmission type using an electromagnetic wave (light) in the visible light region is known. Among them, the electromagnetic induction type has already been put into practical use. This has the advantage that it can be realized with a simple circuit (transformer system), but there is also a problem that the transmission distance is short.

  Therefore, recently, electric field / magnetic field resonance type power transmission capable of short-distance transmission (up to 2 m) has attracted attention. Among these, in the case of the electric field resonance type, when a hand or the like is put in the transmission path, the human body is a dielectric, so that energy is absorbed as heat and dielectric loss occurs. On the other hand, in the case of the magnetic resonance type, the human body hardly absorbs energy, and dielectric loss can be avoided. From this point of view, attention to the magnetic resonance type has been increasing.

  When power is transmitted and received in a non-contact manner using such an electromagnetic induction type or magnetic field resonance type configuration, it is difficult to efficiently transmit power unless the power receiver is properly arranged with respect to the power transmitter. . For example, a magnetic field resonance type power transmitting and receiving device as described in Patent Document 1 is said to have a relatively high positioning likelihood as compared with a power transmitting and receiving device using electromagnetic induction. Some positioning device is required.

  In Patent Document 1, when power is supplied in a non-contact manner from a power transmission coil (power transmission resonance coil) provided in a power supply facility to a power reception coil (power reception resonance coil) provided in a moving body such as a vehicle, power transmission resonance is performed. A configuration for appropriately adjusting the mutual positional relationship between the coil and the power receiving resonance coil is disclosed. That is, the position of the power transmission resonance coil is detected, the position of the mobile body is detected, and the direction of the magnetic field vector generated by the power transmission resonance coil is calculated based on the position of the power transmission resonance coil and the position of the mobile body. Thus, by adjusting the direction of the power transmission resonance coil or the power reception resonance coil so as to coincide with the direction of the magnetic field vector, it is possible to perform power feeding at an arbitrary position with high efficiency.

  However, the angle correction mechanism as described in Patent Document 1 can be installed in a large device such as an automobile, but in the case of a small device, it cannot be installed from the viewpoint of device space and device cost. On the other hand, when the power receiving device is incorporated into a small device, the angle between the power transmission resonance coil of the power transmission device and the power reception resonance coil of the power reception device may be greatly inclined depending on the shape of the device. For small consumer equipment with a small allowable cost increase, it is possible to set an angle with a reduced cost by arranging a restricting member with a low likelihood for the angle. However, since an operation for accurately mounting the device including the power receiving resonance coil at a predetermined place is required, the burden on the apparatus user is large. In recent years, universalization has been sought for device handling, and a device configuration that is low in cost and less burdensome on the user is desired.

  Therefore, Patent Document 2 discloses a method for improving the shape of the power receiving resonance coil and enabling efficient charging with a simple configuration suitable for a small device regardless of the positional relationship between the electronic device and the charging device. Is disclosed. That is, a coil is wound around the outer periphery of three adjacent surfaces of a rectangular parallelepiped or cube-shaped iron core (ferromagnetic core) to form a power receiving resonance coil, and power is transmitted in a non-contact manner by electromagnetic induction in a direction perpendicular to each surface of the iron core Configure.

  The winding loop of the power receiving resonance coil has a projected area with respect to all the planes of the x axis y axis plane, the y axis z axis plane, and the z axis x axis plane. As a result, the electromagnetic fields from the three axial directions of the x-axis, y-axis, and z-axis directions always intersect the loop of the power receiving resonance coil, so that power can be received in the three-axis directions. That is, it is possible to stably receive power regardless of the installation posture of the power receiving resonance coil.

JP 2010-98896 A JP 2010-80851 A

  However, as in Patent Document 2, in a configuration using a ferromagnetic core for the power receiving resonance coil, when the core is not used for the power transmission resonance coil, the magnetic field line density on the power transmission side is insufficient and high efficiency power transmission is expected. Can not. In addition, when a core is used for the power transmission resonance coil, high efficiency power transmission is possible in the direction perpendicular to each surface of the core where the cores can be sufficiently close to each other. However, if the gap is large, high efficiency power transmission is difficult. It is generally known that

  In other words, the magnetic resistance on the power transmission side and the power reception side is increased by the gap, and the apparent permeability is greatly reduced. As in the case where there is no core, the magnetic field lines cannot be effectively transmitted to the power reception side, making it difficult to perform highly efficient power transmission It is.

  Thus, in the case of electromagnetic induction using a core, there is a possibility that high efficiency can be obtained in multiple directions by winding a coil three-dimensionally, but the direction in which high efficiency is obtained depends on the shape of the core. To do. In addition, in a rectangular parallelepiped or cubic core as in Patent Document 2, the direction in which high efficiency is obtained is limited to only three directions perpendicular to each surface.

  The present invention provides a non-contact power transmission device that has a high likelihood of a relative angle between a power transmission resonance coil and a power reception resonance coil for suppressing a decrease in transmission efficiency, and can obtain a practically sufficiently high transmission efficiency without providing an angle correction means. The purpose is to provide.

  A non-contact power transmission device of the present invention includes a power transmission device having a power transmission coil unit including a power transmission resonance coil, and a power reception device including a power reception coil unit including a power reception resonance coil, and the power transmission resonance coil and the power reception resonance coil. Electric power is transmitted from the power transmitting apparatus to the power receiving apparatus via magnetic field resonance between the power transmitting apparatus and the power receiving apparatus. One of the power transmission resonance coil and the power reception resonance coil has a three-dimensional shape that is three-dimensionally bent or curved, and the other resonance coil has a planar shape. The three-dimensional resonance coil is configured such that there are at least three partial plane regions defined by a bent or curved portion of the coil winding, and each of the portions with respect to the plane of the planar resonance coil The plane directions of the plane regions are different from each other.

  According to the non-contact power transmission apparatus having the above configuration, the relative angle between the power transmission resonance coil and the power reception resonance coil changes due to the presence of at least three partial plane regions having different surface directions in the three-dimensional shape of one resonance coil. Even so, the range of the relative angle with a small change in the projected area with respect to the planar resonance coil and a small change in the power transmission efficiency is expanded. Accordingly, practically sufficiently high transmission efficiency can be obtained without providing an angle correction means. As a result, a small, low-cost and highly efficient non-contact power transmission device can be obtained.

The figure which shows notionally the structure of the non-contact electric power transmission apparatus in Embodiment 1. The front view which shows an example of the shape of the power transmission coil unit which comprises the same non-contact electric power transmission apparatus, and a receiving coil unit The perspective view which shows an example of the shape of the power transmission coil unit which comprises the non-contact electric power transmission apparatus It is a figure which shows an example of the shape of the receiving resonance coil which comprises the same non-contact electric power transmission apparatus, (a) is a top view, (b) is a front view, (c) is a side view The perspective view which shows the shape before the bending process which laminated | stacked and arrange | positioned the receiving coil and receiving resonance coil which comprise the receiving coil unit of the non-contact electric power transmission apparatus The perspective view which shows the shape after bending the laminated body of the receiving coil and receiving resonance coil which were shown to FIG. 5A of the non-contact electric power transmission apparatus. The perspective view which shows the shape before the bending process which formed the receiving coil and the receiving resonance coil which comprise the receiving coil unit of the non-contact electric power transmission apparatus on one board | substrate. The perspective view which shows the shape after bending the structure of the receiving coil and receiving resonance coil which were shown to FIG. 6A of the non-contact electric power transmission apparatus The figure which shows the relationship between an inclination angle and electric power transmission efficiency when a receiving coil unit is inclined with respect to the power transmission coil unit in the non-contact electric power transmission apparatus The figure explaining the direction of the rotation center axis when inclining the receiving coil unit in the non-contact power transmission device The figure which shows the relationship between the transmission distance and transmission efficiency of the non-contact electric power transmission equipment The perspective view which shows the structure and arrangement | positioning of the power transmission coil unit and power receiving coil unit which comprise the non-contact electric power transmission apparatus in Embodiment 2. FIG. The figure which shows the relationship between an inclination angle and electric power transmission efficiency when a receiving coil unit is inclined with respect to the power transmission coil unit in the non-contact electric power transmission apparatus The perspective view which shows the structure and arrangement | positioning of the power transmission coil unit which comprises the non-contact electric power transmission apparatus of the comparative example 1, and a receiving coil unit The figure which shows the relationship between the inclination angle of the receiving coil unit of the non-contact electric power transmission apparatus, and transmission efficiency The perspective view which shows the structure and arrangement | positioning of the power transmission coil unit which comprises the non-contact electric power transmission apparatus of the comparative example 2, and a receiving coil unit The figure which shows an example of the relationship between the inclination angle in the 1st direction of the receiving coil unit of the same non-contact electric power transmission apparatus, and transmission efficiency The figure which shows an example of the relationship between the inclination angle in the 2nd direction of the receiving coil unit of the non-contact electric power transmission apparatus, and transmission efficiency The figure which shows an example of the relationship between the inclination angle in the 3rd direction of the receiving coil unit of the same non-contact electric power transmission apparatus, and transmission efficiency The perspective view which shows the structure and arrangement | positioning of the non-contact electric power transmission apparatus power transmission coil unit and power receiving coil unit in Embodiment 3. The perspective view which shows the shape before the bending process of the receiving coil unit which laminated | stacked and arrange | positioned the receiving coil and receiving resonance coil which comprise the non-contact electric power transmission apparatus The perspective view which shows the shape after the bending process of the laminated body of the receiving coil and the receiving resonance coil which were shown to FIG. 18A of the non-contact electric power transmission apparatus. The perspective view which shows the shape before the bending process of the receiving coil unit which formed the receiving coil and receiving resonance coil which comprise the non-contact electric power transmission apparatus on one board | substrate. The perspective view which shows the shape after bending the structure of the receiving coil and receiving resonance coil which were shown to FIG. 19A of the non-contact electric power transmission apparatus. The figure which shows the relationship between an inclination angle and electric power transmission efficiency when a receiving coil unit is inclined with respect to the power transmission coil unit in the non-contact electric power transmission apparatus

  The non-contact power transmission apparatus of the present invention can take the following aspects based on the above configuration.

  That is, the projection region of the three-dimensional resonance coil with respect to the plane of the planar resonance coil can be included in the region of the planar resonance coil.

  Further, the three-dimensional resonance coil is a shape obtained by bending or bending a hexagonal coil in a planar shape, and a first diagonal line connecting a pair of apexes adjacent to one apex of the hexagon, and It can be set as the structure which has a Z-shaped side shape bent or curved by the 2nd diagonal line which tied a pair of vertex adjacent to a pair of said vertex as a boundary. In this case, the angle of bending or bending of the Z-shaped side surface shape can be set to 90 degrees.

  Further, the three-dimensional resonance coil has a loop along an outer shape of an L-shaped plane that is developed on three faces adjacent to one vertex of a hexahedron, and is bent along the three faces of the hexahedron. It can be set as the structure which has a shape.

  Further, each of the power transmission coil unit and the power reception coil unit may be configured by a conductive layer pattern formed on a substrate, and the three-dimensional resonance coil may be bent or curved together with the substrate. .

  The power transmission coil unit includes a power transmission resonance coil and a power supply coil that has the same shape as the power transmission resonance coil and supplies power to the power transmission resonance coil by electromagnetic induction, and the power reception coil unit includes the power reception resonance. A coil and a power receiving coil that has the same shape as the power receiving resonant coil and receives power from the power receiving resonant coil by electromagnetic induction, and the power transmitting resonant coil and the power feeding coil are formed on different substrates, respectively. The power receiving resonance coil and the power receiving coil are formed on different substrates and overlapped with each other, and the power feeding coil or the power receiving coil combined with the three-dimensional resonance coil is The structure may be bent or curved together with the substrate.

  The power transmission coil unit includes a power transmission resonance coil and a power supply coil that has the same shape as the power transmission resonance coil and supplies power to the power transmission resonance coil by electromagnetic induction, and the power reception coil unit includes the power reception resonance. A coil and a power receiving coil that has the same shape as the power receiving resonant coil and receives power from the power receiving resonant coil by electromagnetic induction, and the power transmitting resonant coil and the power feeding coil are arranged on the same substrate. The power receiving resonance coil and the power receiving coil are formed so as to surround the power transmitting resonance coil, and the power receiving coil is formed on the same substrate so that the power receiving coil surrounds the power receiving resonance coil. The feeding coil or the receiving coil combined with the resonant coil having a shape is bent or bent together with the substrate. It can be curved Configurations.

  Hereinafter, a non-contact power transmission apparatus according to an embodiment of the present invention will be described with reference to the drawings.

<Embodiment 1>
FIG. 1 is a diagram illustrating a schematic configuration of a power transmission device 1 and a power reception device 2 that constitute the contactless power transmission device according to the first embodiment. The power transmission device 1 includes a power transmission coil unit 3 in which a power feeding coil 3a and a power transmission resonance coil 3b are combined. The power receiving device 2 includes a power receiving coil unit 4 in which a power receiving coil 4a and a power receiving resonance coil 4b are combined. A high-frequency power driver 5 is connected to the feeding coil 3a of the power transmission device 1, and the power of the AC power source (AC 100V) 6 is converted into high-frequency power that can be transmitted and supplied. A rechargeable battery 8 is connected to the power receiving coil 4 a of the power receiving device 2 as an example of a load via a rectifier 7.

  The feeding coil 3a is excited by the high frequency power of the frequency f0 supplied from the high frequency power driver 5, and transmits the high frequency power to the power transmission resonance coil 3b by electromagnetic induction. The power transmission resonance coil 3b generates a magnetic field by the high frequency power output from the power supply coil 3a. The high frequency power supplied to the power transmission resonance coil 3b is transmitted in a non-contact manner to the power reception resonance coil 4b by magnetic field resonance. The transmitted high frequency power is transmitted from the power receiving resonance coil 4 b to the power receiving coil 4 a by electromagnetic induction, rectified by the rectifier 7 and supplied to the rechargeable battery 8.

  The power feeding coil 3a and the power receiving coil 4a are not necessarily required, and the power transmitting coil unit 3 can be configured only by the power transmitting resonant coil 3b, and the power receiving device 2 can be configured by only the power receiving resonant coil 4b. In this case, any known configuration may be adopted for power feeding to the power transmission resonance coil 3b and power reception from the power reception resonance coil 4b.

  A capacitor 9 is connected to the power transmission resonance coil 3b, thereby forming a power transmission resonator. Further, the capacitor 10 is also connected between both ends of the power receiving resonance coil 4b, and a power receiving resonator is configured. Capacitors 9 and 10 are provided to adjust the resonance frequencies of the power transmission resonator and the power reception resonator. However, the configuration is not necessarily limited to a configuration in which a variable capacitor is provided as a circuit element as illustrated, and a fixed capacitor may be connected or a configuration using a stray capacitance may be used. The power receiving device 2 can also be configured to supply the output of the rectifier by adjusting the voltage with a DC / DC converter.

  The configuration of the non-contact power transmission apparatus shown in FIG. 1 is basically the same as that of the conventional apparatus, but in the present embodiment, the configurations of the power transmission coil unit 3 and the power receiving coil unit 4 are the same as those of the conventional example. Have different characteristics. In FIG. 1, the shapes of the power transmission coil unit 3 and the power reception coil unit 4 are conceptually illustrated, but actually have shapes as described below.

  FIG. 2 is a front view showing a basic configuration of the power transmission coil unit 3 and the power reception coil unit 4 of the present embodiment. A perspective view of the power transmission coil unit 3 is shown in FIG. The power feeding coil 3a and the power transmission resonance coil 3b constituting the power transmission coil unit 3 are both configured to form an octagonal planar loop, and the power transmission resonance coil 3b is superimposed on the power supply coil 3a. The power supply coil 3a is wound by one turn, and the power transmission resonance coil 3b is wound by a plurality of turns.

  On the other hand, as can be seen from FIG. 2, the power receiving coil unit 4 has a three-dimensional shape. An example of the shape of the power receiving resonance coil 4b is shown in FIG. In the figure, (a) is a plan view, (b) is a front view, and (c) is a side view. As shown in FIG. 4A, the power receiving resonance coil 4b basically has a hexagonal planar shape and forms vertices 11a to 11f. Then, as shown in FIGS. 4B and 4C, the side shape is, for example, Z-shaped with the first diagonal line connecting the vertices 11b and 11f and the second diagonal line connecting 11c and 11e as boundaries. It has a bent solid shape. The bending angle α is 90 degrees as an example. The power receiving coil 4a has the same shape and outer dimensions as the power receiving resonant coil 4b, and is disposed along the outside of the power receiving resonant coil 4b as shown in FIG.

  According to the three-dimensional shape described above, in the power receiving resonance coil 4b, each of the two ridge lines sandwiching the bent portions of the vertices 11b, 11d, and 11f defines three different partial plane regions A to C. For example, the partial plane region A is defined by the ridge lines 11a-11c and the ridge lines 11b-11c that sandwich the bent portion of the vertex 11b. The plane directions of these partial plane regions A to C are different from each other with respect to the plane of the planar power transmission resonance coil 3b. As a result, the effects described later can be obtained.

  Further, as shown in FIG. 2, the projection area of the three-dimensional power receiving resonance coil 4b with respect to the plane of the planar power transmission resonance coil 3b is included in the area of the power transmission resonance coil 3b. In other words, the external dimensions of the power receiving resonant coil 4b viewed in the direction perpendicular to the plane of the power transmitting resonant coil 3b are smaller than the external dimensions of the power transmitting resonant coil 3b.

  Note that the bent portion may be in a curved state without forming a clear corner. Therefore, the description of “bending” in the following description includes a curved and bent form.

  In addition, the power receiving resonance coil 4b (the same applies to the power receiving coil 4a) can be formed into a curved shape by winding a wire along a previously bent base material. Alternatively, in order to facilitate manufacture, it is desirable to adopt a method in which the power receiving coil unit 4 is formed as a planar coil on a plastically deformable planar substrate and then bent. The planar coil can be produced, for example, as a conductive layer pattern in which a metal film is formed on a substrate and patterned by etching. Examples of such aspects are shown in FIGS. 5A, 5B, 6A, and 6B.

  5A and 5B are such that the power receiving coil 4a and the power receiving resonance coil 4b are formed on different substrates. FIG. 5A shows the shape before bending. The power receiving coil 4a is formed on the substrate 12, and the power receiving resonance coil 4b is formed on the substrate 13 and overlaps with each other. FIG. 5B shows the shape after bending. In the bending process, for example, the two resonance coils 4a and 4b in the state of FIG. Bend 90 degrees. Further, with the two vertices 11c and 11e adjacent to the vertex 11d as the uppermost point as a boundary, the upper ridge line is bent 90 degrees toward the back.

  Further, when impedance matching is established between the power receiving coil 4a and the load on the power receiving side, or when a matching circuit is provided between the power receiving coil 4a and the load, the same substrate as shown in FIGS. 6A and 6B. 14, the power receiving resonance coil 4 b and the power receiving coil 4 a can be formed. The bending process may be the same as in FIG. 5B, but FIG. 6B shows another mode. That is, the substrate 14 is placed horizontally, and the left ridge line is bent 90 degrees downward with the two vertices 11b and 11f adjacent to the left vertex 11a as a boundary. Further, with the two vertices 11c and 11e adjacent to the right vertex 11d as a boundary, the right ridge line is bent upward 90 degrees.

  As described above, by making the power receiving resonance coil 4b bent or curved, the deterioration of transmission efficiency when the power receiving coil unit 4 is tilted with respect to the power transmitting coil unit 3 is suppressed. Can do. This is because even if the power receiving coil unit 4 is tilted, the change in the projected area of the power receiving resonant coil 4b with respect to the power transmitting resonant coil 3b is small.

  That is, as shown in FIG. 4A, the power receiving resonance coil 4b has three different partial plane regions A to C. These partial plane areas A to C have mutually different plane directions with respect to the plane including the power transmission resonance coil 3b. For this reason, no matter how the power receiving coil unit 4 is tilted, the projected area of the partial plane regions A to C with respect to the power transmission resonance coil 3b includes a decreasing portion and an increasing portion, and the power transmission resonance of the power reception resonance coil 4b. The change in the projected area with respect to the coil 3b is small. As a result, the amount of magnetic flux that the magnetic flux formed by the power transmission resonance coil 3b interlinks with the power reception resonance coil 4b is not easily affected by the change in inclination, and the deterioration of transmission efficiency is suppressed.

  FIG. 7A shows a result of comparing the change in transmission efficiency when the power receiving coil unit 4 is rotated around the central axis in various directions with respect to the power transmitting coil unit 3. In the figure, the legend angle θ (= 0 °, 45 °, 135 °) is the angle θ formed between the rotation center axis 15 on the XY plane and the Y axis in FIG. 7B. The diameter of the circumscribed circle of the feeding coil 3a and the power transmission resonance coil 3b was φ70 mm, and the length of one side of the power reception coil 4a and the power reception resonance coil 4b was 20 mm.

  The distance between the power transmission coil unit 3 and the power reception coil unit 4 is represented by the average distance Dm measured at the center in the vertical direction of the power reception coil unit 4 as shown in FIG. The power receiving coil unit 4 was rotated around the rotation center axis 15 while maintaining a constant average distance Dm = 20 mm. As can be seen from FIG. 7A, a substantially constant transmission efficiency is obtained when the tilt angle is within a range of ± 50 degrees or less, even if it is rotated around any rotation center axis 15. It can be seen that even if the inclination angle slightly exceeds the range of ± 50 degrees, the same effect can be obtained. If the inclination angle is ± 60 degrees or less, the range of change in transmission efficiency is practically sufficiently suppressed within the range.

  Next, FIG. 8 shows how the power transmission efficiency changes when the power receiving coil unit 4 is tilted by changing the average distance Dm between the power transmitting coil unit 3 and the power receiving coil unit 4. The values obtained by changing the average distance Dm are 20 mm, 25 mm, 30 mm, and 35 mm as shown in the legend in the figure. In this case, as the average distance Dm between the power transmission coil unit 3 and the power reception coil unit 4 increases, the likelihood of the inclination angle tends to decrease, but the angle at which the transmission efficiency is halved compared to the transmission efficiency at the inclination angle of 0 degree. Is ± 60 degrees or more.

  In the above-described configuration, an example in which the three-dimensional shape is formed by bending a coil formed in a planar shape at two boundary lines is shown, but the bending boundary may exceed two locations.

  As described above, according to the present embodiment, one of the power transmission resonance coil and the power reception resonance coil has a three-dimensional shape that is three-dimensionally bent or curved, and the other resonance coil has a planar shape. Have. The three-dimensional shape is configured such that there are at least three partial plane regions defined by the bent or curved portions of the coil winding, and the plane direction of each partial plane region with respect to the plane of the planar resonance coil Are configured to be different from each other.

<Embodiment 2>
A non-contact power transmission apparatus according to Embodiment 2 will be described with reference to FIG. The configuration as the non-contact power transmission device is basically the same as the device of the first embodiment shown in FIG. 1, and the configurations of the power transmission coil unit and the power reception coil unit are different from those of the first embodiment.

  FIG. 9 is a perspective view showing an example of the configuration of the power transmission coil unit 16 and the power reception coil unit 17. The power transmission coil unit 16 has a three-dimensional shape, and the power reception coil unit 17 has a planar shape and is larger in outer shape than the power transmission coil unit 16.

  The power supply coil 16a and the power transmission resonance coil 16b have the same shape as the power reception coil 4a and the power reception resonance coil 4b in the first embodiment, the planar shape is a hexagon, and the side surface shape is bent in a Z shape. The bending angle α is 90 degrees. The power reception coil 17a and the power reception resonance coil 17b have the same planar shape as the power supply coil 3a and the power transmission resonance coil 3b of the power transmission coil unit 3 in the first embodiment.

  The projection region of the three-dimensional power transmission resonance coil 16b with respect to the plane of the planar power reception resonance coil 17b is included in the region of the power reception resonance coil 17b.

  FIG. 10 shows a result of comparing changes in transmission efficiency when the power receiving coil unit 17 is rotated around the central axis in various directions with respect to the power transmitting coil unit 16. In the figure, the legend angle θ (= 0 °, 45 °, 135 °) indicates the angle θ formed between the rotation center axis 15 on the XY plane and the Y axis, similarly to the angle shown in FIG. 7B. The length of one side of the power feeding coil 16a and the power transmission resonance coil 16b was 20 mm, and the diameter of the circumscribed circle of the power reception coil 17a and the power reception resonance coil 17b was 70 mm.

  The distance between the power transmission coil unit 16 and the power reception coil unit 17 is represented by the average distance Dm measured at the center in the vertical direction of the power transmission coil unit 16 as in the embodiment shown in FIG. The receiving coil unit 17 was rotated around the rotation center axis 15 while maintaining the average distance Dm constant at 40 mm.

  In this case, if the power reception coil unit 17 is tilted by 50 degrees or more, the power transmission resonance coil 16b and the power reception resonance coil 17b physically interfere with each other. Therefore, measurement was performed within a range of ± 50 degrees. There was almost no change in transmission efficiency in the measured range.

  The specific structures of the power transmission coil unit 16 and the power reception coil unit 17, how to bend and bend can take the same various aspects as in the first embodiment.

<Comparative Example 1>
The measurement regarding the non-contact electric power transmission apparatus of the comparative example 1 for verifying the effect by each above-mentioned embodiment is demonstrated. The basic configuration of the non-contact power transmission apparatus of Comparative Example 1 is the same as that of the above-described embodiment, and the configurations of the power transmission coil unit and the power reception coil unit are different from those of the embodiment.

  The configurations of the power transmission coil unit and the power reception coil unit of Comparative Example 1 were as shown in FIG. In this example, the power transmission coil unit 3 having the same planar shape as that of the first embodiment is used, and the power receiving coil unit 18 having a small planar shape is used. The diameter of the circumscribed circle of the power feeding coil 3a and the power transmitting resonance coil 3b was φ70 mm, and the diameter of the circumscribed circle of the power receiving coil 18a and the power receiving resonant coil 18b was φ20 mm.

  FIG. 12 shows how the transmission efficiency changes when the distance between the power transmission coil unit 3 and the power reception coil unit 18 is changed and the power reception coil unit 18 is tilted with respect to the power transmission coil unit 3.

  When the power receiving coil unit 18 is tilted, unlike the first and second embodiments, there is no region where the power transmission efficiency does not change, and the power transmission efficiency decreases as the tilt angle of the power receiving coil unit 18 increases. To do. The angle at which the transmission efficiency is halved compared to the transmission efficiency when the tilt angle is 0 degree is about ± 50 degrees. Therefore, it can be seen that the transmission efficiency in the case of the devices of the above-described embodiments is less influenced by the inclination of the power receiving coil unit than in the first comparative example.

<Comparative example 2>
The measurement regarding the non-contact electric power transmission apparatus of the comparative example 1 for verifying the effect by each above-mentioned embodiment is demonstrated. The basic configuration of the contactless power transmission apparatus of Comparative Example 2 is the same as that of the above-described embodiment, and the configurations of the power transmission coil unit and the power reception coil unit are different from those of the embodiment.

  The configurations of the power transmission coil unit and the power reception coil unit of Comparative Example 2 were as shown in FIG. In this example, the power transmission coil unit 19 has a hexagonal three-dimensional shape, and the power receiving coil unit 18 has a planar shape, as in the second embodiment. However, unlike the second embodiment, the outer shape of the power transmission coil unit 19 is larger than the outer shape of the power receiving coil unit 18.

  One side of the power supply coil 19a and the power transmission resonance coil 19b was 50 mm, and the diameter of the circumscribed circle of the power reception coil 18a and the power reception resonance coil 18b was 20 mm.

  Changes in the power transmission efficiency when the average distance Dm between the power transmission coil unit 19 and the power reception coil unit 18 is changed and the power reception coil unit 18 is tilted with respect to the power transmission coil unit 19 are shown in FIGS. Shown in

  FIG. 14 shows the relationship between the inclination angle of the power receiving coil unit 18 relative to the power transmitting coil unit 19 and the transmission efficiency when the power receiving coil unit 18 is rotated around the Y axis shown in FIG. The cases where the average distance Dm is 5, 10, 15, and 20 mm are shown. As in the case of Comparative Example 1, it can be seen that the angle at which the transmission efficiency is halved compared to the transmission efficiency when the tilt angle is 0 degrees is about ± 50 degrees.

  Next, FIG. 15 shows the relationship between the inclination angle of the power receiving coil unit 18 relative to the power transmitting coil unit 19 and the transmission efficiency when the power receiving coil unit 18 is rotated about the X axis shown in FIG. The cases where the average distance Dm is 5, 10, 15, and 20 mm are shown. As in the case of Comparative Example 1, the angle at which the transmission efficiency is halved compared to the transmission efficiency when the tilt angle is 0 degrees is about ± 50 degrees.

  Next, the relationship between the inclination angle of the power reception coil unit 18 relative to the power transmission coil unit 19 and the transmission efficiency when the power reception coil unit 18 is rotated about an axis inclined by β = 45 degrees from the X axis shown in FIG. Is shown in FIG. The cases where the average distance Dm is 5, 15, and 20 mm are shown. Compared to the cases shown in FIGS. 14 and 15, the inclination angle dependence is slightly better, but the angle at which the transmission efficiency is halved compared to the transmission efficiency when the inclination angle is 0 degree is less than ± 60 degrees. .

  From the above, it can be seen that the transmission efficiency in the case of the devices of the above-described embodiments is less affected by the inclination of the power receiving coil unit than in Comparative Example 2.

<Embodiment 3>
A non-contact power transmission apparatus according to Embodiment 3 will be described with reference to FIGS. 17, 18A, 18B, 19A, and 19B. The configuration as a non-contact power transmission device is basically the same as the device of the first embodiment shown in FIG. 1, and the configurations of the power transmission coil unit and the power reception coil unit are different from those of the first and second embodiments. To do.

  FIG. 17 is a perspective view showing a basic configuration of the power transmission coil unit 3 and the power reception coil unit 20 of the present embodiment. The power transmission coil unit 3 has the same configuration as that of the first embodiment, and the power feeding coil 3a and the power transmission resonance coil 3b have a planar shape. The power receiving coil unit 20 has a three-dimensional shape. A bent structure for forming a three-dimensional shape is different from that of the first embodiment.

  However, also in the present embodiment, the three-dimensional shapes of the power receiving coil 20a and the power receiving resonance coil 20b are set so as to satisfy the same conditions as in the above-described embodiment. That is, it is configured such that there are at least three partial plane regions defined by the bent or curved portion of the winding of the power receiving resonance coil 20b. And it is comprised so that the direction of the plane of each partial plane area | region of the receiving resonance coil 20b may mutually differ with respect to the plane of the power transmission resonance coil 3b.

  Further, as shown in FIG. 17, the projection area of the three-dimensional power receiving resonance coil 20b with respect to the plane of the planar power transmission resonance coil 3b is included in the area of the power transmission resonance coil 3b. That is, the outer dimensions of the power receiving resonance coil 20b viewed in the direction perpendicular to the plane of the power transmission resonance coil 3b are smaller than the outer dimensions of the power transmission resonance coil 3b.

  Specifically, as shown in FIG. 17, the basic structure of the power receiving coil unit 20 has a shape in which a winding loop is formed along three adjacent ridgelines around one vertex of a hexahedron. More precisely, it has a coil shape in which the loop along the outer shape of the L-shaped plane developed from the three surfaces is bent along the three surfaces returned to the position of the original hexahedron.

  In order to produce the power receiving coil unit 20, it is desirable to adopt a method of bending the power receiving coil unit 20 after forming the power receiving coil unit 20 on a flat substrate that can be plastically deformed, as in the first and second embodiments. Examples of such aspects are shown in FIGS. 18A, 18B, 19A, and 19B.

  In the example of FIGS. 18A and 18B, the power reception coil 20a and the power reception resonance coil 20b are formed on different planar substrates. FIG. 18A shows a shape before bending and is L-shaped. The power receiving coil 20a is formed on a plastically deformable substrate 21, and the power receiving resonance coil 20b is formed on a plastically deformable substrate 22 and is superposed on each other. FIG. 18B shows the shape after bending. In the bending process, among the ridge lines defining the three faces of the hexahedron, two ridge lines crossing the inside of the L-shape are bent at 90 degrees as boundaries.

  When impedance matching is established between the power receiving coil 20a and the load on the power receiving side, or when a matching circuit is provided between the power receiving coil 20a and the load, as shown in FIGS. 19A and 19B, the same substrate 23 is used. The power receiving resonance coil 20b and the power receiving coil 20a may be formed. The bending process may be the same as in the case of FIG. 18B.

  FIG. 20 shows a result of comparison of transmission efficiency when the power receiving coil unit 20 is rotated around the central axis in various directions. The diameter of the feeding coil and the feeding-side resonance coil is 70, and the length of one side of the receiving coil and the receiving resonance coil is 20 mm. The coil was rotated with respect to the coil center so that the average distance between the power transmission coil and the power reception coil did not change at a distance of 20 mm.

  Since the inner portion of the L-shaped coil becomes the folded portion of the pattern when the coil is bent, the efficiency is reduced by about 3 points compared to the first embodiment. However, as shown in the figure, the central axis in any direction Even if it is rotated around the same angle, almost the same efficiency is obtained in the range of ± 60 degrees or more.

  According to the non-contact power transmission device of the present invention, the likelihood of the relative angle between the power transmission resonance coil and the power reception resonance coil with respect to the suppression of the decrease in transmission efficiency is large, and the transmission efficiency is sufficiently high practically without using the angle correction means. can get. Therefore, it is suitable for non-contact power transmission in small devices such as mobile phones and hearing aids, TVs and electric vehicles.

DESCRIPTION OF SYMBOLS 1 Power transmission apparatus 2 Power reception apparatus 3, 16 Power transmission coil unit 3a, 16a Power feeding coil 3b, 16b Power transmission resonance coil 4, 17 Power reception coil unit 4a, 17a Power reception coil 4b, 17b Power reception resonance coil 5 High frequency power driver 6 AC power supply 7 Rectifier 8 Rechargeable battery 9, 10 Capacitors 11a-11f Vertex 12, 13, 14 Substrate 15 Center axis of rotation

Claims (8)

A power transmission device having a power transmission coil unit including a power transmission resonance coil;
A power receiving device having a power receiving coil unit including a power receiving resonance coil,
In the non-contact power transmission device that transmits power from the power transmission device to the power reception device via magnetic field resonance between the power transmission resonance coil and the power reception resonance coil,
Either one of the power transmission resonance coil or the power reception resonance coil has a three-dimensional shape that is three-dimensionally bent or curved, and the other resonance coil has a planar shape,
The three-dimensional resonance coil is configured such that there are at least three partial plane regions defined by a bent or curved portion of the coil winding,
The non-contact power transmission device according to claim 1, wherein the plane directions of the partial plane regions with respect to the plane of the planar resonance coil are different from each other.   The non-contact power transmission apparatus according to claim 1, wherein a projection area of the three-dimensional resonance coil with respect to a plane of the planar resonance coil is included in an area of the planar resonance coil. The three-dimensional resonance coil is a shape obtained by bending or bending a hexagonal coil in a planar shape,
A Z-shaped, bent or curved with a first diagonal line connecting a pair of vertices adjacent to one vertex of the hexagon and a second diagonal line connecting a pair of vertices adjacent to the pair of vertices as a boundary The non-contact power transmission device according to claim 1, wherein the non-contact power transmission device has a side shape.   The contactless power transmission device according to claim 3, wherein an angle of bending or bending of the Z-shaped side shape is 90 degrees.   The three-dimensional resonance coil has a shape obtained by bending a loop along an outer shape of an L-shaped plane that develops three adjacent surfaces around one vertex of a hexahedron along the three surfaces of the hexahedron. The non-contact power transmission device according to claim 1 or 2. Each of the power transmission coil unit and the power reception coil unit is configured by a conductive layer pattern formed on a substrate,
The non-contact power transmission apparatus according to claim 1, wherein the three-dimensional resonance coil is bent or curved together with the substrate. The power transmission coil unit is configured by a power feeding coil that has the same shape as the power transmission resonance coil and the power transmission resonance coil and feeds the power transmission resonance coil by electromagnetic induction.
The power receiving coil unit is configured by a power receiving coil that has the same shape as the power receiving resonant coil and the power receiving resonant coil and receives power from the power receiving resonant coil by electromagnetic induction,
The power transmission resonance coil and the power feeding coil are formed on different substrates and overlapped with each other,
The power receiving resonance coil and the power receiving coil are formed on different substrates and overlapped with each other,
The contactless power transmission device according to claim 6, wherein the feeding coil or the receiving coil combined with the three-dimensional resonance coil is bent or curved together with the substrate. The power transmission coil unit is configured by a power feeding coil that has the same shape as the power transmission resonance coil and the power transmission resonance coil and feeds the power transmission resonance coil by electromagnetic induction.
The power receiving coil unit is configured by a power receiving coil that has the same shape as the power receiving resonant coil and the power receiving resonant coil and receives power from the power receiving resonant coil by electromagnetic induction,
The power transmission resonance coil and the power supply coil are formed on the same substrate so that the power supply coil surrounds the power transmission resonance coil,
The power receiving resonance coil and the power receiving coil are formed on the same substrate so that the power receiving coil surrounds the power receiving resonance coil,
The contactless power transmission device according to claim 6, wherein the feeding coil or the receiving coil combined with the three-dimensional resonance coil is bent or curved together with the substrate.

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