JP2021077826A - Coil unit, power transmitting device, power receiving device and power transmission system - Google Patents

Abstract

To suppress the significant decrease in transmission efficiency due to coil misalignment.SOLUTION: A coil 120 is configured by spirally winding a conductor around a coil shaft 121. A magnetic body 130 is opposed to the coil 120 and has an opening 130A. A lead-out part 122D extends in the direction along the coil shaft 121 from an end part 122B of the coil 120 through the opening 130A. A lead-out part 122E extends from a connection portion with the lead-out part 122D in the direction away from the coil shaft 121. A conductor plate 140 is disposed between the magnetic body 130 and the lead-out part 122E.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to coil units, power transmission devices, power receiving devices and power transmission systems.

Wireless power transfer technology, which transmits power wirelessly, is attracting attention. Since wireless power transmission technology can wirelessly supply power from a power transmission device to a power receiving device, it is expected to be applied to various products such as transportation equipment such as trains and electric vehicles, home appliances, electronic equipment, wireless communication equipment and toys. .. Here, the coil unit used for power transmission or power reception generally includes a coil that constitutes a resonance circuit together with a capacitor, and a magnetic material such as ferrite that converges the magnetic field lines generated by the coil.

Patent Document 1 discloses a power transmission unit including a power transmission coil in which a conducting wire is provided in a spiral shape around an axis and a ferrite provided so as to face the power transmission coil. This power transmission coil connects a coil winding portion wound from the inside to the outside and an intermediate portion connected to the inside end portion of the coil winding portion and crossing from the inside to the outside of the coil winding portion. Be prepared. In the power transmission unit disclosed in Patent Document 1, an intermediate portion, which is a leader wire that substantially pulls out the inner end of the coil to the outside of the coil, is arranged on the side opposite to the ferrite when viewed from the coil. To.

Japanese Unexamined Patent Publication No. 2019-71748

Here, in order to suppress the length of the power transmission unit in the thickness direction (direction in which the axis extends), in the power transmission unit described in Patent Document 1, ferrite is arranged between the coil and the leader wire. It is preferable to be transformed into. However, in such a configuration, due to the influence of the magnetic flux generated by the current flowing through the leader wire, the amount of change in the mutual inductance due to the misalignment of the coil depends on the direction of the misalignment, and the transmission efficiency is significantly reduced depending on the direction of the misalignment. To do.

The present disclosure has been made in view of the above problems, and an object of the present disclosure is to suppress a significant decrease in transmission efficiency due to a misalignment of a coil in a power transmission system that transmits power wirelessly.

In order to solve the above problems, in the coil unit according to the embodiment of the present disclosure, a coil having a conducting wire spirally wound around a first axis and a coil facing the coil and having a first hole opened. From the connection portion between the magnetic material having the portion, the first extraction portion extending from the inner peripheral end of the coil through the first opening portion and in the direction along the first axis, and the first extraction portion, the first It includes a second drawer portion extending in a direction away from one axis, and a first conductor plate arranged between the magnetic material and the second drawer portion.

According to the coil unit having the above configuration, it is possible to suppress a significant decrease in transmission efficiency due to the displacement of the coil.

Schematic configuration diagram of the power transmission system according to the first embodiment of the present disclosure. Block diagram showing the configuration of the power transmission system according to the first embodiment of the present disclosure. Top view of the power transmission coil unit according to the first embodiment of the present disclosure. Sectional drawing of the power transmission coil unit which concerns on Embodiment 1 of this disclosure Top view of the power transmission coil unit according to the second embodiment of the present disclosure. Sectional drawing of the power transmission coil unit which concerns on Embodiment 2 of this disclosure Top view of the power transmission coil unit according to the third embodiment of the present disclosure. Sectional drawing of the power transmission coil unit which concerns on Embodiment 3 of this disclosure Top view of the power transmission coil unit according to the fourth embodiment of the present disclosure. Sectional drawing of the power transmission coil unit which concerns on Embodiment 4 of this disclosure Top view of the power transmission coil unit according to the fifth embodiment of the present disclosure. Sectional drawing of the power transmission coil unit which concerns on Embodiment 5 of this disclosure Sectional drawing of the power transmission coil unit which concerns on Embodiment 6 of this disclosure Top view of the power transmission coil unit according to the seventh embodiment of the present disclosure. Sectional drawing of power transmission coil unit which concerns on Embodiment 7 of this disclosure Sectional drawing of the power receiving coil unit which concerns on Embodiment 8 of this disclosure

Hereinafter, the power transmission system according to the embodiment of the technique according to the present disclosure will be described with reference to the drawings. In the following embodiments, the same components are designated by the same reference numerals. In addition, the size ratio and shape of the components shown in each figure are not necessarily the same as those at the time of implementation.

(Embodiment 1)
The power transmission system according to the present embodiment can be used for charging secondary batteries of various devices such as mobile devices such as smartphones, EVs (Electric Vehicles), and industrial devices. Hereinafter, a case where the power transmission system executes charging of the EV storage battery will be illustrated.

FIG. 1 is a diagram showing a schematic configuration of a power transmission system 1000 used for charging a storage battery 410 provided in an electric vehicle 400. The electric vehicle 400 runs by using a motor driven by electric power charged in a storage battery 410 such as a lithium ion battery or a lead storage battery as a power source. In FIG. 1, the vertically upward axis is orthogonal to the Z axis and the Z axis, and the axis extending in the traveling direction of the electric vehicle 400 is orthogonal to the X axis, the Z axis and the X axis, and extends from the right side to the left side of the electric vehicle 400. The axis is the Y axis.

As shown in FIG. 1, the power transmission system 1000 is a system that wirelessly transmits power from the power transmission device 100 to the power reception device 200 by magnetic coupling. The power transmission system 1000 includes a power transmission device 100 that wirelessly transmits (wirelessly supplies power) the power of an AC or DC commercial power source 300 to the electric vehicle 400, and a power receiving device 200 that receives the power transmitted by the power transmission device 100 and charges the storage battery 410. And. In the following description, it is assumed that the commercial power supply 300 is an AC power supply.

The power transmission device 100 is a device that wirelessly transmits power to the power receiving device 200 by magnetic coupling. The power transmission device 100 includes a power transmission coil unit 10 that transmits AC power to the electric vehicle 400, and a power supply circuit 110 that supplies AC power to the power transmission coil unit 10. The power supply circuit 110 includes a power factor improving circuit 170 for improving the power factor of commercial AC power supplied by the commercial power supply 300, and an inverter circuit 180 for generating AC power supplied to the power transmission coil unit 10. The power transmission device 100 is fixed to the floor of the parking lot, for example.

The power receiving device 200 is a device that wirelessly receives power from the power transmitting device 100 by magnetic coupling. The power receiving device 200 includes a power receiving coil unit 20 that receives the AC power transmitted by the power transmission device 100, and a rectifying circuit 270 that converts the AC power supplied from the power receiving coil unit 20 into DC power and supplies it to the storage battery 410. Be prepared. The power receiving device 200 is fixed to, for example, the chassis of the electric vehicle 400.

With reference to FIG. 2, the configuration of the power transmission system 1000 and the flow of power during power transmission will be described.

The AC power generated by the commercial power supply 300 is rectified and boosted by the power factor improving circuit 170, and converted into DC power having a predetermined voltage value. The power factor improving circuit 170, for example, has a plurality of diodes constituting the diode bridge, a capacitor that smoothes the current output by the diode bridge, an inductor that suppresses the passage of high frequency components, and a phase difference between voltage and current. It includes a MOS ( Metal-Oxide-Semiconductor) -FET ( Field-Effect Transistor) to be adjusted, a diode that suppresses the backflow of current, and an electrolytic capacitor that smoothes the current output to the inverter circuit 180. The DC power generated by the power factor improving circuit 170 by converting the power is converted into AC power having a predetermined frequency by the inverter circuit 180. This frequency is, for example, a frequency of 75 kHz to 90 kHz. The inverter circuit 180 includes, for example, a plurality of N-channel power MOS-FETs constituting a full bridge circuit.

The AC power generated by the inverter circuit 180 by converting the power is supplied to the power transmission coil unit 10. The power transmission coil unit 10 includes a coil 120 that induces an alternating magnetic field Φ by flowing an AC current with the application of an AC voltage, and capacitors 111 and 112 provided at both ends of the coil 120, respectively. The capacitor 111, the coil 120, and the capacitor 112 are connected in series to form a resonance circuit.

The power receiving coil unit 20 includes a coil 220 that induces a counter electromotive force in response to a change in the alternating magnetic flux Φ induced by the coil 120, and capacitors 211 and 212 provided at both ends of the coil 220. The capacitor 211, the coil 220, and the capacitor 212 are connected in series to form a resonance circuit. When the electric vehicle 400 is stopped at a preset position, the coil 220 faces the coil 120, and the alternating magnetic field Φ induced by the coil 120 interlinks with the coil 220.

The rectifier circuit 270 rectifies the counter electromotive force induced in the coil 220 to generate DC power. The DC power generated by the rectifier circuit 270 is supplied to the storage battery 410. Even if the power receiving device 200 includes a charging circuit between the rectifier circuit 270 and the storage battery 410, the DC power supplied from the rectifier circuit 270 is converted into an appropriate DC power for charging the storage battery 410. Good.

Next, the power transmission coil unit 10 in which the coil 120 and the members around the coil 120 are integrated will be described with reference to FIGS. 3 and 4. Since the power receiving coil unit 20 in which the coil 220 and the members around the coil 220 are integrated has basically the same configuration as the power transmission coil unit 10, description thereof will be omitted as appropriate.

FIG. 3 is a top view of the power transmission coil unit 10. FIG. 4 is a cross-sectional view of the power transmission coil unit 10 when the power transmission coil unit 10 is cut along the plane shown by the line AA in FIG. The power transmission coil unit 10 is a unit in which a case 11, a capacitor 111, a capacitor 112, a coil 120, a magnetic material 130, and a conductor plate 140 are integrated.

The case 11 is a case for accommodating the capacitor 111, the capacitor 112, the coil 120, the magnetic material 130, and the conductor plate 140. In addition, in FIG. 3 and FIG. 4, the outer edge of the case 11 is shown by a dotted line for easy understanding, and the member for fixing the member housed in the case 11 to the case 11 is not shown. Further, in FIGS. 3 and 4, in order to facilitate understanding, the illustration of the capacitor 111 and the capacitor 112 is omitted. The capacitor 111 is provided, for example, on a substrate provided in the case 11, and is provided at any part of the wiring connecting one end of the coil 120 and the power supply circuit 110. Further, the capacitor 112 is provided, for example, on the substrate and is provided at any part of the wiring connecting the other end of the coil 120 and the power supply circuit 110. The case 11 is made of, for example, an insulator such as a resin.

The coil 120 is a planar coil in which a conducting wire 122 is spirally wound around a coil shaft 121. The coil axis 121 is parallel to the Z axis, and the coil surface of the coil 120 is orthogonal to the Z axis. The conductor 122 is made of, for example, a conductor such as copper. The surface of the conductor 122 is covered with an insulator such as resin. The coil 120 is an example of a coil and a power transmission coil in the present disclosure. The coil shaft 121 is an example of the first shaft in the present disclosure. The conductor 122 is an example of the conductor in the present disclosure.

The magnetic material 130 is a soft magnetic material. The magnetic body 130 is arranged in close proximity to the coil 120 so as to face the coil 120. The magnetic body 130 passes the magnetic force generated by the coil 120 to suppress the loss of the magnetic force. The magnetic material 130 has a plate-like shape with a hole in the central portion, and has an open portion 130A. The magnetic material 130 is composed of, for example, ferrite which is a composite oxide of iron oxide and a metal. The magnetic material 130 is an example of the magnetic material in the present disclosure. The perforated portion 130A is an example of the first perforated portion in the present disclosure. The magnetic material 130 may be composed of an aggregate of a plurality of magnetic material pieces, and by arranging the plurality of magnetic material pieces in a frame shape, the magnetic material 130 has an opening portion 130A in the central portion. 130 may be configured.

As shown in FIG. 4, the conductor 122 includes a winding portion 122A, a drawer portion 122D, a drawer portion 122E, and a drawer portion 122F. In FIG. 4, the portion showing the cross section of the line AA in FIG. 3 is shown with hatching. Further, in order to facilitate understanding, in FIG. 4, the portions that do not appear in this cross section, specifically, the drawer portion 122D, the drawer portion 122E, and the drawer portion 122F are shown without hatching.

The winding portion 122A is a portion of the conducting wire 122 that is wound in a spiral shape. Of the two end portions included in the winding portion 122A, the inner peripheral end, which is the end portion arranged inside, is referred to as the end portion 122B. Of the two ends included in the winding portion 122A, the outer peripheral end, which is the end portion arranged on the outside, is referred to as the end portion 122C. In the present embodiment, the side closer to the coil shaft 121 is referred to as the inner side, and the side farther from the coil shaft 121 is referred to as the outer side. The lead-out portion 122D is a portion of the conducting wire 122 that extends from the end portion 122B through the opening portion 130A in the direction along the coil shaft 121. In FIGS. 3 and 4, the direction along the coil shaft 121 is the Z-axis direction. Therefore, the lead-out portion 122D is a portion of the conducting wire 122 that extends from the end portion 122B in the negative direction in the Z-axis direction.

The lead-out portion 122E is a portion of the conducting wire 122 that extends in a direction away from the coil shaft 121 from the connection portion with the lead-out portion 122D. The direction away from the coil shaft 121 is, for example, in a plane orthogonal to the coil shaft 121 and passing through the connecting portion between the drawing portion 122D and the drawing portion 122E, from the intersection of this plane and the coil shaft 121 toward the connecting portion. The direction. In the present embodiment, the direction away from the coil shaft 121 is the negative direction of the X-axis. The lead-out portion 122F is a portion of the conducting wire 122 that extends in a direction away from the coil shaft 121 from the connection portion with the end portion 122C.

The drawer portion 122E and the drawer portion 122F each come out of the case 11 through the holes provided in the case 11. The drawer portion 122D and the drawer portion 122E substantially play a role of pulling out the inner peripheral end of the coil 120 to the outside of the case 11. The drawer portion 122F substantially plays a role of pulling out the outer peripheral end of the coil 120 to the outside of the case 11. Although not shown, the capacitor 111 and the capacitor 112 are provided at any part of the wiring connecting the coil 120 and the power supply circuit 110. For example, the capacitor 111 is provided in a portion arranged inside the case 11 on the wiring connecting the extraction portion 122F and the power supply circuit 110. Further, for example, the capacitor 112 is provided in a portion arranged inside the case 11 on the wiring connecting the extraction portion 122E and the power supply circuit 110. The end 122B is an example of the inner peripheral end of the coil in the present disclosure. The drawer unit 122D is an example of the first drawer unit in the present disclosure. The drawer unit 122E is an example of the second drawer unit in the present disclosure.

The conductor plate 140 is a plate-shaped member made of a paramagnetic metal having a property of not being strongly magnetized. The conductor plate 140 is arranged between the magnetic material 130 and the drawer portion 122E. The conductor plate 140 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic material 130, and suppresses the influence of the alternating magnetic flux Φ generated from the extraction portion 122E on the magnetic flux density distribution in the magnetic material 130. To do. That is, the conductor plate 140 shields the magnetic body 130 from the alternating magnetic flux Φ generated from the extraction portion 122E. The conductor plate 140 is, for example, a plate-shaped member made of aluminum. The conductor plate 140 is an example of the first conductor plate in the present disclosure.

Hereinafter, the role of the conductor plate 140 will be described in detail. In the power transmission system 1000, in order to realize efficient power transmission from the power transmission device 100 to the power reception device 200, the coil 120 and the coil 220 need to face each other in parallel at a predetermined distance. Here, when the coil shaft 121 of the coil 120 (hereinafter, appropriately referred to as “coil shaft A”) and the coil shaft of the coil 220 (hereinafter, appropriately referred to as “coil shaft B”) overlap, the coil 120 And the coil 220 are most closely coupled via the alternating magnetic field Φ, and the most efficient power transmission is achieved.

Assuming that the coupling coefficient k (where k = 0 to 1) indicates the degree of magnetic coupling between the coil 120 and the coil 220, the relative positional relationship between the coil 120 and the coil 220 changes. The coupling coefficient k also changes accordingly. Further, when the coupling coefficient k changes, the mutual inductance between the coil 120 and the coil 220 also changes, and the transmission efficiency also changes. In this embodiment, the coil 220 is displaced with respect to the coil 120. Further, in the present embodiment, it is assumed that the coil 220 does not shift in the Z-axis direction and does not shift in the Z-axis direction.

The drawer portion 122E is arranged close to the magnetic body 130. Therefore, in the absence of the conductor plate 140, the drawer portion 122E affects the magnetic flux density distribution in the magnetic material 130. For example, as shown in FIG. 3, when the extraction portion 122E is arranged in the negative direction of the X axis when viewed from the coil shaft 121, the alternating magnetic field induced in the region where the coordinates of the X axis are smaller than the coil shaft 121. The distribution of Φ and the distribution of the alternating magnetic field Φ induced in the region where the coordinates of the X axis are larger than the coil axis 121 are not symmetrical. As described above, in the absence of the conductor plate 140, anisotropy occurs in the magnetic distribution.

Therefore, for example, the amount of change in the coupling coefficient k when the coil shaft B deviates from the position where the coil shaft B overlaps the coil shaft A by A cm in the positive direction of the X axis, and the amount of change in the coupling coefficient k from the position where the coil shaft B overlaps the coil shaft A of the X axis. It is different from the amount of change in the coupling coefficient k when the deviation is A cm in the negative direction. That is, the amount of change in the coupling coefficient k due to the misalignment of the coil 220 depends on the direction of the misalignment of the coil 220. Therefore, both the amount of change in mutual inductance and the amount of change in transmission efficiency depend on the direction of displacement of the coil 220.

That is, in the absence of the conductor plate 140, there may be a misalignment direction in which the transmission efficiency is significantly reduced, and the transmission efficiency may be significantly reduced depending on the misalignment direction. Therefore, in the absence of the conductor plate 140, it is required to narrow the allowable range of misalignment or lower the guaranteed range of transmission efficiency.

However, in the present embodiment, the conductor plate 140 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic body 130. Therefore, the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E has little influence on the magnetic flux density distribution in the magnetic body 130, and the anisotropy of the magnetic distribution is reduced. Therefore, the amount of change in the coupling coefficient k, the mutual inductance, and the transmission efficiency due to the displacement of the positional relationship between the coil 120 and the coil 220 does not depend much on the direction of the displacement. Therefore, there is no misalignment direction in which the transmission efficiency is significantly reduced, and the transmission efficiency is not significantly reduced in any direction of the misalignment.

In the present embodiment, the conductor plate 140 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic body 130. Therefore, according to the present embodiment, the anisotropy of the magnetic distribution can be reduced, and a significant decrease in transmission efficiency due to the misalignment of the coil 220 can be suppressed.

(Embodiment 2)
In the first embodiment, an example in which the outer edge of the magnetic body 130 and the outer edge of the conductor plate 140 are significantly different from each other when viewed from the direction in which the coil shaft 121 extends has been described. Further, in the first embodiment, an example in which the power loss due to the eddy current generated in the conductor plate 140 is not considered has been described. In the present embodiment, an example will be described in which the outer edge of the magnetic body 130 and the outer edge of the conductor plate substantially overlap with each other when viewed from the direction in which the coil shaft 121 extends, and the power loss due to the eddy current generated in the conductor plate is taken into consideration. The description of the same configuration, functions, and the like as in the first embodiment will be omitted or simplified. Hereinafter, the power transmission coil unit 10A according to the present embodiment will be described with reference to FIGS. 5 and 6.

FIG. 5 is a top view of the power transmission coil unit 10A. FIG. 6 is a cross-sectional view of the power transmission coil unit 10A when the power transmission coil unit 10A is cut along the plane shown by the line BB in FIG. The power transmission coil unit 10A is a unit in which a case 11, a capacitor 111, a capacitor 112, a coil 120, a magnetic material 130, and a conductor plate 141 are integrated.

The conductor plate 141 has a plate shape with a hole in the central portion, and has an open portion 141A. The outer edge of the conductor plate 141 substantially overlaps with the outer edge of the magnetic body 130 when viewed from the direction in which the coil shaft 121 extends. The outer edge of the conductor plate 141 may be located outside the outer edge of the magnetic body 130 when viewed from the direction in which the coil shaft 121 extends. The conductor plate 141 is arranged between the magnetic body 130 and the drawer portion 122E so as to face the magnetic body 130. The conductor plate 141 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic material 130, and suppresses the influence of the alternating magnetic flux Φ generated from the extraction portion 122E on the magnetic flux density distribution in the magnetic material 130. To do. That is, the conductor plate 141 shields the magnetic body 130 from the alternating magnetic flux Φ generated from the extraction portion 122E. The conductor plate 141 is made of a paramagnetic metal such as aluminum. The conductor plate 141 is an example of the first conductor plate in the present disclosure. The perforated portion 141A is an example of the second perforated portion in the present disclosure.

The extraction portion 122D extends from the end portion 122B, which is the inner peripheral end of the coil 120, through the opening portion 130A and the opening portion 141A in the direction along the coil shaft 121. That is, the drawer portion 122D extends from the end portion 122B through the opening portion 130A and the opening portion 141A in the negative direction of the Z axis.

In the present embodiment, D1, which is the distance between the magnetic material 130 and the conductor plate 141, is less than T1, which is the thickness of the magnetic material 130. As described above, when the distance between the magnetic material 130 and the conductor plate 141 is extremely short, the eddy current generated in the conductor plate 141 due to the alternating magnetic flux Φ is large, the amount of heat generated by the conductor plate 141 is large, and the conductor plate 141 is generated. Power loss due to heat generation is large. Therefore, in the present embodiment, the shape and arrangement of the conductor plate 141 are adopted so that a portion having a particularly high density of the alternating magnetic flux Φ is not generated in the conductor plate 141 as much as possible.

Specifically, in the present embodiment, the end portion 141B, which is the end portion on the coil shaft 121 side at the portion overlapping the drawer portion 122E of the conductor plate 141 when viewed from the direction in which the coil shaft 121 extends, extends the coil shaft 121. It is farther from the coil shaft 121 than the end portion 130B, which is the end portion on the coil shaft 121 side in the portion overlapping the drawer portion 122E of the magnetic body 130 when viewed from the direction. In other words, the end 141B is recessed outward from the end 130B. The end 141B is an example of the first end in the present disclosure. The end 130B is an example of a second end in the present disclosure.

In order to realize such a configuration, the opening area of the opening portion 141A is made larger than the opening area of the opening portion 130A, and the end portion 141B is outside the end portion 130B regardless of the arrangement location of the drawer portion 122E. It is preferable to arrange it in. According to such a configuration, the eddy current is not generated so much and the calorific value is not so large even at the end 141B where the density of the alternating magnetic flux Φ tends to be high among the conductor plates 141. As a result, the amount of heat generated by the entire conductor plate 141 is reduced, and the power loss due to heat generation is reduced. Here, how much the end portion 141B is arranged outside the end portion 130B can be appropriately adjusted.

For example, it is preferable that S1, which is the distance between the end portion 141B and the end portion 130B when viewed from the direction in which the coil shaft 121 extends, is T1 or less, which is the thickness of the magnetic material 130. According to such a configuration, it is possible to reduce the anisotropy of the magnetic distribution while reducing the power loss due to heat generation.

It has been confirmed by experiments under predetermined conditions that the power loss due to heat generation can be sufficiently reduced even if S1 does not exceed T1. In this experiment, the correspondence between S1 which is the amount of retracting of the end 141B to the outside with respect to the end 130B and P1 which is the power loss due to the eddy current generated in the conductor plate 141 was measured. In this experiment, the measurement result is that P1 is about 115 W when S1 is −T1, P1 is about 108 W when S1 is 0, and P1 is about 65 W when S1 is + T1. Obtained.

From this measurement result, in order to reduce the power loss, it is desirable that the end portion 141B is retracted to the outside of the end portion 130B, and the end portion 141B is outside the end portion 130B by the thickness of the magnetic material 130. It can be seen that the power loss is sufficiently reduced if it is retracted. It is also clear that if the end 141B retracts too far outward with respect to the end 130B, the anisotropy of the magnetic distribution is not sufficiently reduced. Therefore, in order to reduce the power loss due to heat generation and the anisotropy of the magnetic distribution at the same time, the end portion 141B is retracted to the outside within the range of the thickness of the magnetic material 130 or less than the end portion 130B. Is preferable.

According to this embodiment, it is possible to reduce the anisotropy of the magnetic distribution while suppressing the thickness of the power transmission coil unit 10A and without causing much power loss due to heat generation. Further, in the present embodiment, since the magnetic material 130 and the conductor plate 141 have substantially the same shape and size, the conductor plate 141 can be easily incorporated into the power transmission coil unit 10A.

(Embodiment 3)
In the second embodiment, when the distance between the magnetic material 130 and the conductor plate 141 is short, in order to reduce the anisotropy of the magnetic distribution, S1 which is the amount of withdrawal of the end portion 141B to the outside with respect to the end portion 130B is set. An example of suppressing the thickness of the magnetic material 130 to T1 or less has been described. In the present embodiment, an example in which the power loss due to heat generation is significantly reduced when the magnetic material 130 and the conductor plate are close to each other and the anisotropy of the magnetic distribution is unlikely to occur will be described. The description of the same configurations, functions, and the like as in the first and second embodiments will be omitted or simplified. Hereinafter, the power transmission coil unit 10B according to the present embodiment will be described with reference to FIGS. 7 and 8.

FIG. 7 is a top view of the power transmission coil unit 10B. FIG. 8 is a cross-sectional view of the power transmission coil unit 10B when the power transmission coil unit 10B is cut along the plane shown by the line CC in FIG. The power transmission coil unit 10B is a unit in which a case 11, a capacitor 111, a capacitor 112, a coil 120, a magnetic material 130, and a conductor plate 142 are integrated.

The conductor plate 142 has a plate shape with a hole in the central portion, and has an open portion 142A. The opening 142A is larger than the opening 130A. When viewed from the direction in which the coil shaft 121 extends, the outer edge of the conductor plate 142 and the outer edge of the magnetic body 130 substantially overlap. The outer edge of the conductor plate 142 may be located outside the outer edge of the magnetic material 130 when viewed from the direction in which the coil shaft 121 extends. The conductor plate 142 is arranged between the magnetic body 130 and the drawer portion 122E so as to face the magnetic body 130. The conductor plate 142 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic material 130, and suppresses the influence of the alternating magnetic flux Φ generated from the extraction portion 122E on the magnetic flux density distribution in the magnetic material 130. To do. That is, the conductor plate 142 shields the magnetic body 130 from the alternating magnetic flux Φ generated from the extraction portion 122E. The conductor plate 142 is made of a paramagnetic metal such as aluminum. The conductor plate 142 is an example of the first conductor plate in the present disclosure. The perforated portion 142A is an example of the second perforated portion in the present disclosure.

The extraction portion 122D extends from the end portion 122B, which is the inner peripheral end of the coil 120, through the opening portion 130A and the opening portion 142A in the direction along the coil shaft 121. That is, the drawer portion 122D extends from the end portion 122B through the opening portion 130A and the opening portion 142A in the negative direction of the Z axis. The drawer portion 122D in the present embodiment is longer than the drawer portion 122D in the second embodiment. The distance D2 between the magnetic body 130 and the drawer portion 122D is longer than T1 which is the thickness of the magnetic body 130.

In the present embodiment, D1, which is the distance between the magnetic material 130 and the conductor plate 142, is shorter than T1, which is the thickness of the magnetic material 130. As described above, when the distance between the magnetic material 130 and the conductor plate 142 is extremely short, the eddy current generated in the conductor plate 142 due to the alternating magnetic flux Φ is large, the amount of heat generated by the conductor plate 142 is large, and the heat generated by the conductor plate 142 is large. The power loss is large. Therefore, in the present embodiment, the shape and arrangement of the conductor plate 142 are devised so that a portion having a particularly high density of the alternating magnetic flux Φ is not generated in the conductor plate 142 as much as possible.

Specifically, in the present embodiment, the end portion 142B, which is the end portion on the coil shaft 121 side at the portion overlapping the drawer portion 122E of the conductor plate 142 when viewed from the direction in which the coil shaft 121 extends, extends the coil shaft 121. It is farther from the coil shaft 121 than the end portion 130B, which is the end portion on the coil shaft 121 side in the portion overlapping the drawer portion 122E of the magnetic body 130 when viewed from the direction. The end 142B is an example of the first end in the present disclosure. The end 130B is an example of a second end in the present disclosure.

Here, in the present embodiment, D2 is longer than T1, and the drawer portion 122E is sufficiently separated from the magnetic material 130. Therefore, the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E does not enter the magnetic material 130 so much even from the portion of the magnetic material 130 that is not shielded by the conductor plate 142. That is, in the present embodiment, the alternating magnetic flux Φ generated from the extraction portion 122E has a small influence on the magnetic flux density distribution in the magnetic body 130, and the anisotropy of the magnetic distribution does not occur so much. Therefore, in the present embodiment, the reduction of power loss due to heat generation is emphasized rather than the reduction of anisotropy of the magnetic distribution.

Specifically, the opening area of the opening portion 142A is made significantly larger than the opening area of the opening portion 130A, and the edge of the opening portion 142A is significantly retracted to the outside of the edge of the opening portion 130A. To. That is, S1 which is the distance between the end portion 142B and the end portion 130B is made to exceed T1 which is the thickness of the magnetic body 130. According to such a configuration, the power loss due to heat generation can be sufficiently reduced.

According to this embodiment, the anisotropy of the magnetic distribution can be reduced without causing power loss due to heat generation as much as possible.

(Embodiment 4)
In the second and third embodiments, when the power loss due to heat generation is large, an example of reducing the anisotropy of the magnetic distribution while suppressing the power loss due to heat generation has been described. In this embodiment, an example of reducing the anisotropy of the magnetic distribution when the power loss due to heat generation is not so large will be described. The description of the same configuration, functions, and the like as those in the first to third embodiments will be omitted or simplified. Hereinafter, the power transmission coil unit 10C according to the present embodiment will be described with reference to FIGS. 9 and 10.

FIG. 9 is a top view of the power transmission coil unit 10C. FIG. 10 is a cross-sectional view of the power transmission coil unit 10C when the power transmission coil unit 10C is cut along the plane shown by the DD line in FIG. The power transmission coil unit 10C is a unit in which a case 11, a capacitor 111, a capacitor 112, a coil 120, a magnetic material 130, and a conductor plate 143 are integrated.

The conductor plate 143 has a plate shape with a hole in the central portion, and has an opening portion 143A. The opening area of the opening portion 143A is substantially the same as the opening area of the opening portion 130A. The conductor plate 143 is arranged between the magnetic body 130 and the drawer portion 122E so as to face the magnetic body 130. The conductor plate 143 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic material 130, and suppresses the influence of the alternating magnetic flux Φ generated from the extraction portion 122E on the magnetic flux density distribution in the magnetic material 130. To do. That is, the conductor plate 143 shields the magnetic body 130 from the alternating magnetic flux Φ generated from the extraction portion 122E. The conductor plate 143 is made of a paramagnetic metal such as aluminum. The conductor plate 143 is an example of the first conductor plate in the present disclosure. The perforated portion 143A is an example of the second perforated portion in the present disclosure.

In the present embodiment, D1, which is the distance between the magnetic material 130 and the conductor plate 143, is T1 or more, which is the thickness of the magnetic material 130. As described above, when the distance between the magnetic material 130 and the conductor plate 142 is long, the eddy current generated in the conductor plate 143 due to the alternating magnetic flux Φ is small, the calorific value of the conductor plate 143 is small, and the conductor plate 143 has a small amount of heat. The power loss due to heat generation is small. Therefore, the reduction of anisotropy of the magnetic distribution is more important than the reduction of power loss due to heat generation.

Specifically, in the present embodiment, the end portion 143B, which is the end portion on the coil shaft 121 side at the portion overlapping the drawer portion 122E of the conductor plate 143 when viewed from the direction in which the coil shaft 121 extends, is the coil shaft 121. Aligns the end 130B, which is the end on the coil shaft 121 side, at the portion that overlaps with the drawer 122E of the magnetic body 130 when viewed from the extending direction. Specifically, the opening area of the opening portion 143A is set to be substantially the same as the opening area of the opening portion 130A so that the edge of the opening portion 143A is aligned with the edge of the opening portion 130A. That is, the end portion 130B and the end portion 143B are aligned when viewed from the direction in which the coil shaft 121 extends. According to such a configuration, the anisotropy of the magnetic distribution can be sufficiently reduced. The end portion 143B is an example of the first end portion in the present disclosure. The end 130B is an example of a second end in the present disclosure.

It has been confirmed by experiments under predetermined conditions that the power loss due to heat generation is sufficiently small when D1 is T1 or more. In this experiment, on the premise that the end portion 130B and the end portion 143B are aligned when viewed from the direction in which the coil shaft 121 extends, D1 which is the distance between the magnetic material 130 and the conductor plate 143 and the eddy current generated in the conductor plate 143 are used. The correspondence with P2, which is the power loss, was measured. In this experiment, it is measured that P2 is about 108W when D1 is 0, P2 is about 38W when D1 is T1, and P2 is about 25W when D1 is twice T1. Results were obtained.

From this measurement result, it can be seen that when the end portion 130B and the end portion 143B are aligned and D1 is T1 or more, the power loss due to heat generation is sufficiently small. Further, it is clear that if the end portion 130B and the end portion 143B are aligned, the anisotropy of the magnetic distribution is reduced.

According to this embodiment, it is possible to reduce the anisotropy of the magnetic distribution while suppressing the increase in power loss due to heat generation.

(Embodiment 5)
In the fourth embodiment, a method of reducing the anisotropy of the magnetic distribution when the power loss due to heat generation is not so large has been described. In this embodiment, an example in which the anisotropy of the magnetic distribution is significantly reduced when the power loss due to heat generation is not so large will be described. The description of the same configuration, functions, and the like as those in the first to fourth embodiments will be omitted or simplified. Hereinafter, the power transmission coil unit 10D according to the present embodiment will be described with reference to FIGS. 11 and 12.

FIG. 11 is a top view of the power transmission coil unit 10D. FIG. 12 is a cross-sectional view of the power transmission coil unit 10D when the power transmission coil unit 10D is cut along the plane shown by the line EE in FIG. The power transmission coil unit 10D is a unit in which a case 11, a capacitor 111, a capacitor 112, a coil 120, a magnetic material 130, and a conductor plate 144 are integrated.

The conductor plate 144 has a plate shape with a hole in the central portion, and has an open portion 144A. The opening area of the opening portion 144A is smaller than the opening area of the opening portion 130A. The conductor plate 144 is arranged between the magnetic body 130 and the drawer portion 122E so as to face the magnetic body 130. The conductor plate 144 suppresses the alternating magnetic flux Φ generated by the current flowing through the extraction portion 122E from entering the magnetic material 130, and suppresses the influence of the alternating magnetic flux Φ generated from the extraction portion 122E on the magnetic flux density distribution in the magnetic material 130. To do. That is, the conductor plate 144 shields the magnetic body 130 from the alternating magnetic flux Φ generated from the extraction portion 122E. The conductor plate 144 is made of a paramagnetic metal such as aluminum. The conductor plate 144 is an example of the first conductor plate in the present disclosure. The perforated portion 144A is an example of the second perforated portion in the present disclosure.

The extraction portion 122D extends from the end portion 122B, which is the inner peripheral end of the coil 120, through the opening portion 130A and the opening portion 144A in the direction along the coil shaft 121. That is, the drawer portion 122D extends from the end portion 122B through the opening portion 130A and the opening portion 144A in the negative direction of the Z axis.

In the present embodiment, D1, which is the distance between the magnetic material 130 and the conductor plate 144, is T1 or more, which is the thickness of the magnetic material 130. As described above, when the distance between the magnetic material 130 and the conductor plate 144 is long, the eddy current generated in the conductor plate 144 due to the alternating magnetic flux Φ is small, the calorific value of the conductor plate 144 is small, and the conductor plate 144 The power loss due to heat generation is small. Therefore, the reduction of anisotropy of the magnetic distribution is more important than the reduction of power loss due to heat generation.

Specifically, in the present embodiment, the end portion 144B, which is the end portion on the coil shaft 121 side at the portion overlapping the drawer portion 122E of the conductor plate 144 when viewed from the extending direction of the coil shaft 121, is the coil shaft 121. Is projected inward from the end portion 130B, which is the end portion on the coil shaft 121 side at the portion overlapping the extraction portion 122E of the magnetic body 130 when viewed from the extending direction. Specifically, the opening area of the opening portion 144A is made smaller than the opening area of the opening portion 130A so that the edge of the opening portion 144A is arranged inside the edge of the opening portion 130A.

That is, the end portion 144B is arranged closer to the coil shaft 121 than the end portion 130B when viewed from the direction in which the coil shaft 121 extends. According to such a configuration, the anisotropy of the magnetic distribution can be significantly reduced. The end 144B is an example of the first end in the present disclosure. The end 130B is an example of a second end in the present disclosure.

According to this embodiment, the anisotropy generated in the magnetic distribution can be significantly reduced without causing much power loss due to heat generation.

(Embodiment 6)
In the fifth embodiment, an example in which the conductor plate 144 that shields the magnetic material 130 from the alternating magnetic flux Φ generated from the drawer portion 122E is housed inside the case 11 has been described. In the present embodiment, the magnetic material 130 is shielded from the alternating magnetic flux Φ by the conductor plate 144 housed inside the case 11, and the alternating magnetic flux Φ is suppressed from leaking to the outside of the case by the conductor plate which is the base plate of the case. An example of doing so will be described. The description of the same configuration, functions, and the like as in the first to fifth embodiments will be omitted or simplified. Hereinafter, the power transmission coil unit 10E according to the present embodiment will be described with reference to FIG.

FIG. 13 is a cross-sectional view of the power transmission coil unit 10E when the power transmission coil unit 10E is cut in the same plane as in the fifth embodiment. The top view of the power transmission coil unit 10E is not shown. The power transmission coil unit 10E is a unit in which a case 11A including a conductor plate 148 as a base plate, a capacitor 111, a capacitor 112, a coil 120, a magnetic material 130, and a conductor plate 144 are integrated. That is, the configuration of the power transmission coil unit 10E is a configuration in which the case 11A including the conductor plate 148 as the base plate is adopted instead of the case 11 provided in the power transmission coil unit 10D.

The conductor plate 148 is a base plate of the case 11A, and is a member for fixing the case 11A to the floor of the parking lot with bolts, for example. The conductor plate 148 is a plate-shaped member. The outer edge of the conductor plate 148 is located outside the outer edge of the magnetic material 130 and the outer edge of the conductor plate 144 when viewed from the direction in which the coil shaft 121 extends. The outer edge of the conductor plate 148 may substantially overlap the outer edge of the magnetic material 130 and the outer edge of the conductor plate 144 when viewed from the direction in which the coil shaft 121 extends. The conductor plate 148 is arranged so as to face the conductor plate 144 via the drawer portion 122E. The conductor plate 144 suppresses the alternating magnetic flux Φ induced by the coil 120 from leaking to the outside of the case 11. The conductor plate 148 is made of a paramagnetic metal such as aluminum. The conductor plate 148 is an example of the second conductor plate in the present disclosure.

According to the present embodiment, it is possible to significantly reduce the anisotropy of the magnetic distribution while suppressing the alternating magnetic flux Φ from leaking to the outside of the case 11 and without causing much power loss due to heat generation. it can.

(Embodiment 7)
In the first to sixth embodiments, an example in which the first drawer portion and the second drawer portion in the present disclosure are composed of the conducting wire 122 has been described. In the present embodiment, an example in which the second lead-out portion in the present disclosure is composed of a member other than the conductor 122 will be described. The description of the same configuration, functions, and the like as those of the first to sixth embodiments will be omitted or simplified. Hereinafter, the power transmission coil unit 10F according to the present embodiment will be described with reference to FIGS. 14 and 15.

FIG. 14 is a top view of the power transmission coil unit 10F. FIG. 15 is a cross-sectional view of the power transmission coil unit 10F when the power transmission coil unit 10F is cut along the plane shown by the line FF in FIG. The power transmission coil unit 10F is a unit in which the case 11, the coil 120, the magnetic material 130, the conductor plate 144, and the substrate 150 are integrated.

The substrate 150 is a circuit board on which various circuits included in the power transmission device 100 or various elements included in these circuits are mounted. For example, the substrate 150 is mounted with at least one of a capacitor 111, a capacitor 112, a power factor improving circuit 170, and an inverter circuit 180. In the present embodiment, the substrate 150 is mounted with the capacitor 111, the capacitor 112, and the inverter circuit 180. The substrate 150 is an example of the substrate in the present disclosure. The capacitor 111 and the capacitor 112 are examples of capacitors in the present disclosure. The inverter circuit 180 is an example of the power supply circuit in the present disclosure.

The substrate 150 includes a terminal 151, a terminal 152, and a conductor portion 153. The terminal 151 is a terminal to which the end of the two ends of the drawer 122D that is not connected to the end 122B is connected. The terminal 152 is a terminal to which one end of the conducting wire 154 is connected. The other end of the conducting wire 154 is pulled out of the case 11 through an opening provided in the case 11 and connected to a circuit or the like outside the case 11.

The conductor portion 153 is a portion formed of a conductor provided on the substrate 150. The conductor portion 153 extends in a direction away from the coil shaft 121 from the connecting portion with the drawer portion 122D. The drawing portion 122D, the conductor portion 153, and the conducting wire 154 substantially play a role of pulling out the inner peripheral end of the coil 120 to the outside of the case 11. The conductor portion 153 may have any configuration as long as the terminal 151 and the terminal 152 are electrically connected to each other. The conductor portion 153 may be configured by wiring connecting the terminal 151 and the terminal 152. Alternatively, the conductor portion 153 may be composed of a wiring that connects the terminal 151 and an element such as a capacitor 111, an element such as a capacitor 111, and a wiring that connects an element such as the capacitor 111 and the terminal 152.

The circuit such as the inverter circuit 180 included in the substrate 150 is a conductor other than the conductor 154, and may be connected to a circuit or the like outside the case 11 by a conductor drawn to the outside of the case 11. The drawer unit 122D is an example of the first drawer unit in the present disclosure. The conductor portion 153 is an example of the second drawer portion in the present disclosure. The substrate 150 is an example of the substrate in the present disclosure.

In the present embodiment, the conductor plate 144 suppresses the alternating magnetic flux Φ generated by the current flowing through the conductor portion 153 from entering the magnetic body 130. Therefore, according to the present embodiment, the anisotropy of the magnetic distribution can be reduced, and a significant decrease in transmission efficiency due to the misalignment of the coil 220 can be suppressed.

(Embodiment 8)
In the seventh embodiment, the power transmission coil unit 10F included in the power transmission device 100 has been described. In this embodiment, the coil unit included in the power receiving device 200 will be described. The description of the same configuration, functions, and the like as those of the first to seventh embodiments will be omitted or simplified. Hereinafter, the configuration of the power receiving coil unit 20F included in the power receiving device 200 according to the present embodiment will be described with reference to FIG. The power receiving coil unit 20F basically has the same configuration as the power transmission coil unit 10F.

FIG. 16 is a cross-sectional view of the power receiving coil unit 20F when the power receiving coil unit 20F is cut in a plane similar to the plane shown by the FF line in FIG. The power receiving coil unit 20F is a unit in which a case 21, a coil 220, a magnetic material 230, a conductor plate 244, and a substrate 250 are integrated.

The case 21 is a case for accommodating the coil 220, the magnetic material 230, the conductor plate 244, and the substrate 250. In FIG. 16, the outer edge of the case 21 is shown by a dotted line for easy understanding, and the member for fixing the member housed in the case 21 to the case 21 is not shown. The case 21 is made of, for example, an insulator such as resin.

The coil 220 has basically the same configuration as the coil 120. The coil 220 is a coil on a plane formed by spirally winding a conducting wire 222 around a coil shaft 221. The coil shaft 221 is parallel to the Z axis, and the coil surface of the coil 220 is orthogonal to the Z axis. The conductor 222 is made of, for example, a conductor such as copper. The surface of the conductor 222 is covered with an insulator such as resin. The coil 220 is an example of the coil and the power receiving coil in the present disclosure. The coil shaft 221 is an example of the first shaft in the present disclosure. The conductor 222 is an example of the conductor in the present disclosure.

The magnetic material 230 basically has the same configuration as the magnetic material 130. The magnetic material 230 is a soft magnetic material. The magnetic material 230 is arranged in close proximity to the coil 220 so as to face the coil 220. The magnetic body 230 passes the magnetic force generated by the coil 120 to suppress the loss of the magnetic force. The magnetic material 230 has a plate-like shape with a hole in the central portion, and has an open portion 230A. The magnetic material 230 is composed of, for example, ferrite which is a composite oxide of iron oxide and a metal. The magnetic material 230 is an example of the magnetic material in the present disclosure. The perforated portion 230A is an example of the first perforated portion in the present disclosure. The magnetic material 230 may be composed of an aggregate of a plurality of magnetic material pieces, and by arranging the plurality of magnetic material pieces in a frame shape, the magnetic material 230 has a hole 230A in the central portion. 230 may be configured.

As shown in FIG. 16, the conductor 222 includes a winding portion 222A, a drawer portion 222D, and a drawer portion 222F. The winding portion 222A is a portion of the conducting wire 222 that is spirally wound. Of the two end portions included in the winding portion 222A, the end portion arranged inside is referred to as the end portion 222B. Of the two end portions included in the winding portion 222A, the end portion arranged on the outside is referred to as the end portion 222C. The lead-out portion 222D is a portion of the conducting wire 222 that extends from the end portion 222B through the opening portion 230A and the opening portion 244A in the direction along the coil shaft 221. In FIG. 16, the direction along the coil shaft 221 is the Z-axis direction. The lead-out portion 222F is a portion of the conducting wire 222 that extends in a direction away from the coil shaft 221 from the connection portion with the end portion 222C.

The drawer portion 222F goes out of the case 21 through a hole provided in the case 21. The drawer portion 222F substantially serves to pull out the outer peripheral end of the coil 220 to the outside of the case 21. The end 222B is an example of the inner peripheral end of the coil in the present disclosure. The drawer portion 222D is an example of the first drawer portion in the present disclosure.

The conductor plate 244 basically has the same configuration as the conductor plate 144. The conductor plate 244 has a plate shape with a hole in the central portion and has an opening portion 244A. The opening area of the opening portion 244A is smaller than the opening area of the opening portion 230A. The conductor plate 244 is arranged between the magnetic body 230 and the conductor portion 253 so as to face the magnetic body 230. The conductor plate 244 suppresses the alternating magnetic flux Φ generated by the current flowing through the conductor portion 253 from entering the magnetic body 230, and suppresses the influence of the alternating magnetic flux Φ generated from the conductor portion 253 on the magnetic flux density distribution in the magnetic body 230. To do. That is, the conductor plate 244 shields the magnetic material 230 from the alternating magnetic flux Φ generated from the conductor portion 253. The conductor plate 244 is made of a paramagnetic metal such as aluminum. The conductor plate 244 is an example of the first conductor plate in the present disclosure. The perforated portion 244A is an example of the second perforated portion in the present disclosure.

The substrate 250 is an electronic substrate on which various circuits included in the power receiving device 200 or various elements included in these circuits are mounted. For example, the substrate 250 is mounted with at least one of a capacitor 211, a capacitor 212, and a rectifier circuit 270. In the present embodiment, the substrate 250 is mounted with the capacitor 211, the capacitor 212, and the rectifier circuit 270. The substrate 250 is an example of the substrate in the present disclosure. The capacitor 211 and the capacitor 212 are examples of capacitors in the present disclosure. The rectifier circuit 270 is an example of the rectifier circuit in the present disclosure.

The substrate 250 includes a terminal 251 and a terminal 252, and a conductor portion 253. The terminal 251 is a terminal to which the end of the two ends of the drawer 222D that is not connected to the end 222B is connected. The terminal 252 is a terminal to which one end of the conducting wire 254 is connected. The other end of the conducting wire 254 is drawn out of the case 21 through an opening provided in the case 21 and connected to a circuit or the like outside the case 21.

The conductor portion 253 is a portion formed of a conductor provided on the substrate 250. The conductor portion 253 extends in a direction away from the coil shaft 221 from the connecting portion with the drawer portion 222D. The drawing portion 222D, the conductor portion 253, and the conducting wire 254 substantially play a role of pulling out the inner peripheral end of the coil 220 to the outside of the case 21. The conductor portion 253 may have any configuration as long as the terminal 251 and the terminal 252 are electrically connected to each other. The conductor portion 253 may be configured by wiring connecting the terminal 251 and the terminal 252. Alternatively, the conductor portion 253 may be composed of a wiring that connects the terminal 251 and an element such as the capacitor 211, and a wiring that connects the element such as the capacitor 211 and the element such as the capacitor 211 and the terminal 252.

The circuit such as the rectifier circuit 270 included in the substrate 250 is a conductor other than the conductor 254, and may be connected to a circuit or the like outside the case 21 by a conductor drawn to the outside of the case 21. The drawer portion 222D is an example of the first drawer portion in the present disclosure. The conductor portion 253 is an example of the second drawer portion in the present disclosure. The substrate 250 is an example of the substrate in the present disclosure.

In the present embodiment, the conductor plate 244 suppresses the alternating magnetic flux Φ generated by the current flowing through the conductor portion 253 from entering the magnetic body 230. Therefore, according to the present embodiment, the anisotropy of the magnetic distribution can be reduced, and a significant decrease in transmission efficiency due to the misalignment of the coil 220 can be suppressed.

(Modification example)
Although the embodiments of the present disclosure have been described above, various modifications and applications are possible in carrying out the present disclosure. In the present disclosure, which part of the configuration, function, and operation described in the above embodiment is adopted is arbitrary. Further, in the present disclosure, in addition to the above-described configurations, functions, and operations, further configurations, functions, and operations may be adopted. In addition, the above-described embodiments can be freely combined as appropriate. In addition, the number of components described in the above embodiment can be adjusted as appropriate. Further, it goes without saying that the materials, sizes, electrical characteristics, and the like that can be adopted in the present disclosure are not limited to those shown in the above embodiments.

For example, in the first embodiment, an example in which the capacitor 111 and the capacitor 112 are provided inside the power transmission coil unit 10 and the capacitor 211 and the capacitor 212 are provided inside the power receiving coil unit 20 has been described. One or both of the capacitor 111 and the capacitor 112 may be provided outside the power transmission coil unit 10, and one or both of the capacitor 211 and the capacitor 212 may be provided outside the power receiving coil unit 20.

For example, in the second embodiment, the conductor plate 141 having the perforated portion 141A is adopted, and the end portion 141B which is the inner end portion of the conductor plate 141 is more than the end portion 130B which is the inner end portion of the magnetic body 130. An example of being placed on the outside has been described. Similar to the first embodiment, the conductor plate 140 having no holes is adopted, and as in the second embodiment, the inner end of the conductor plate 140 is from the end 130B which is the inner end of the magnetic body 130. May also be placed on the outside. Also in the third embodiment, a conductor plate 140 having no holes may be adopted.

In the sixth embodiment, an example in which the conductor plate 148 constituting the base plate of the case is adopted as the conductor plate for suppressing the alternating magnetic flux Φ from leaking to the outside of the case has been described. The conductor plate that prevents the alternating magnetic flux Φ from leaking to the outside of the case is not limited to the conductor plate 148 that constitutes the base plate of the case. For example, as a conductor plate for suppressing leakage of the alternating magnetic flux Φ to the outside of the case, a conductor plate provided inside the case and arranged so as to face the conductor plate 144 via a drawer portion 122E. A board may be adopted.

Although some embodiments of the present disclosure have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

10, 10A, 10B, 10C, 10D, 10E, 10F Transmission coil unit 11, 11A, 21 Case 20, 20F Power receiving coil unit 100 Transmission device 111, 112, 211,212 Capacitor 120, 220 Coil 121,221 Coil shaft 122, 222,154,254 Conductors 122A, 222A Winding parts 122B, 122C, 130B, 141B, 142B, 143B, 144B, 222B, 222C Ends 122D, 122E, 122F, 222D, 222F Drawers 130, 230 Magnetic materials 130A, 141A , 142A, 143A, 144A, 230A, 244A Perforations 140, 141, 142, 143, 144, 148, 244 Conductor plate 150, 250 Substrate 151, 152, 251,252 Terminals 153, 253 Conductor 170 Power factor improvement circuit 180 Inverter circuit 200 Power receiving device 270 rectifying circuit 300 Commercial power supply 400 Electric vehicle 410 Storage battery 1000 Power transmission system

Claims (19)

A coil in which a conducting wire is spirally wound around the first axis,
A magnetic material facing the coil and having a first opening,
A first extraction portion extending from the inner peripheral end of the coil through the first opening portion in a direction along the first axis, and a first extraction portion.
A second drawer extending from the connection portion with the first drawer in a direction away from the first axis,
A first conductor plate arranged between the magnetic material and the second drawer portion is provided.
Coil unit. The distance between the magnetic material and the first conductor plate is less than the thickness of the magnetic material.
The first end, which is the end on the side of the first axis in the portion of the first conductor plate that overlaps with the second drawer when viewed from the direction in which the first axis extends, is from the direction in which the first axis extends. Seen, it is farther from the first axis than the second end, which is the end on the side of the first axis in the portion of the magnetic material that overlaps with the second drawer.
The coil unit according to claim 1. The first conductor plate has a second opening portion and has a second opening portion.
The first extraction portion extends from the inner peripheral end of the coil through the first opening portion and the second opening portion in a direction along the first axis.
The coil unit according to claim 2. The distance between the first end portion and the second end portion when viewed from the direction in which the first axis extends is equal to or less than the thickness of the magnetic material.
The coil unit according to claim 2 or 3. The distance between the magnetic material and the second extraction portion is longer than the thickness of the magnetic material.
The coil unit according to claim 2 or 3. The distance between the magnetic material and the first conductor plate is equal to or greater than the thickness of the magnetic material.
The coil unit according to claim 1. The first end, which is the end on the side of the first axis in the portion of the first conductor plate that overlaps with the second drawer when viewed from the direction in which the first axis extends, is from the direction in which the first axis extends. Seen, it is closer to the first axis than the second end, which is the end on the side of the first axis in the portion of the magnetic material that overlaps with the second drawer.
The coil unit according to claim 6. The first conductor plate has a second opening portion and has a second opening portion.
The first extraction portion extends from the inner peripheral end of the coil through the first opening portion and the second opening portion in a direction along the first axis.
The coil unit according to claim 6 or 7. The first conductor plate has a second opening portion and has a second opening portion.
The first extraction portion extends from the inner peripheral end of the coil through the first opening portion and the second opening portion in a direction along the first axis.
The opening area of the second opening is smaller than the opening area of the first opening.
The coil unit according to claim 6. A second conductor plate facing the first conductor plate is further provided with the second lead-out portion interposed therebetween.
The coil unit according to any one of claims 1 to 9. The first lead-out portion and the second lead-out portion are composed of the conductor.
The coil unit according to any one of claims 1 to 10. A substrate having a conductor portion connected to the first drawer portion is further provided.
The second drawer portion is composed of the conductor portion.
The coil unit according to any one of claims 1 to 10. The substrate includes a capacitor that forms a resonant circuit with the coil.
The coil unit according to claim 12. The coil is a power transmission coil.
The substrate includes a power supply circuit that supplies AC power to the coil.
The coil unit according to claim 12 or 13. The coil is a power receiving coil.
The substrate includes a rectifier circuit that rectifies the AC power received by the coil.
The coil unit according to claim 12 or 13. The coil unit according to any one of claims 1 to 14 is provided.
Power transmission device. The coil unit according to any one of claims 1 to 13 and 15.
Power receiving device. The power transmission device according to claim 16 and
A power receiving device that receives power from the power transmitting device, and the like.
Power transmission system. The power receiving device according to claim 17,
A power transmission device that transmits power to the power receiving device, and the like.
Power transmission system.

Images