JP6332799B2 - Coil unit and power supply system - Google Patents

Description

  The present invention relates to a coil unit used in a power feeding unit or a power receiving unit and a power feeding system including the coil unit.

  2. Description of the Related Art Conventionally, in a power feeding system that supplies power from a power feeding unit to a power receiving unit in a contactless manner, a configuration in which a resonance capacitor (circuit component) is provided in the power feeding unit and the power receiving unit has been disclosed (for example, see Patent Document 1). In a non-contact power supply system, in general, the leakage reactance is large because the power receiving unit and the power supply unit are separated from each other. Therefore, in the power supply system described in Patent Document 1, the leakage reactance is compensated by a capacitor to improve the power factor, and the power supply efficiency is improved.

JP 2014-93829 A

  However, in a non-contact power supply system, it is preferable to generate a high frequency magnetic flux in the coil of the power supply unit in order to increase power supply efficiency, but when this magnetic flux crosses an electric wire other than the coil, a high frequency current flows, In a circuit component such as a capacitor, a large loss may occur and heat may be generated. In particular, as shown in FIG. 6, in the circuit unit 100 having the capacitor 101 and the circuit pattern 102, an annular closed circuit is formed when the capacitors 101 are connected in parallel to increase the capacity. When the magnetic flux B increases or decreases, a current I0 that circulates in the closed circuit flows. This current I0 is attenuated by circulating through the closed circuit, and accordingly, the closed circuit generates heat.

  Then, although the structure which arrange | positions the circuit part which has a circuit component in the position where a magnetic flux density is low (for example, the position away from a coil) can be considered as an example, the freedom degree of arrangement | positioning of a circuit part is low, a power supply part and a power receiving part There is a possibility that the coil unit used in the process will be enlarged and the entire power supply system will be enlarged.

  The objective of this invention is providing the coil unit and electric power feeding system which can suppress an enlargement, suppressing the electric current which flows into a circuit by passage of magnetic flux.

  In order to solve the problems and achieve the object, the invention described in claim 1 is a coil unit used in the power supply unit or the power reception unit in a power supply system that supplies power from the power supply unit to the power reception unit in a contactless manner. A circuit unit including a coil, a circuit board on which a circuit pattern is formed, and a circuit component mounted on the circuit board, and a circuit unit configured by the circuit pattern and the circuit component is electrically connected to the coil. Two adjacent circuits arranged so that currents generated by magnetic flux cancel each other, and the circuit unit includes a plurality of circuit parts connected in series to each other. A coil unit comprising at least one set of circuit part pairs constituted by parts.

  According to a second aspect of the present invention, in the first aspect of the present invention, the planar shape of the pair of circuit portions is such that the two circuit portions are convex in opposite directions, and the whole is a wave shape. It is characterized by that.

  The invention described in claim 3 is characterized in that, in the invention described in claim 1, the shape of the circuit portion pair in plan view is an 8-shaped shape.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, the planar view shape of each of the two circuit portions of the circuit portion pair is an annular shape whose axial direction is the thickness direction of the wiring board. The two circuit portions are overlapped in the plate thickness direction, and are arranged so as to surround the axial directions opposite to each other when the circuit portion pair is traced from one end to the other end. It is what.

  The invention described in claim 5 is the invention described in any one of claims 1 to 4, wherein the substrate body is arranged so that the axis of the coil and the thickness direction of the wiring board coincide with each other. It is arranged to face the end of the coil.

  The invention described in claim 6 is a power supply system that supplies power in a non-contact manner from the power supply unit to the power reception unit, and at least one of the power reception unit and the power supply unit is any one of claims 1 to 5. A power supply system comprising the coil unit described in item 1.

  According to the invention described in claim 1, since the two circuit parts constituting the circuit part pair are arranged so that the currents generated by the magnetic flux cancel each other, the circuit part is located at a position where the magnetic flux density is high. Even if it arrange | positions, an electric current can be suppressed, the freedom degree of arrangement | positioning of a board | substrate body can be improved, and the enlargement of a coil unit can be suppressed.

  According to the invention described in claim 2, since the two circuit portions are convex in opposite directions and the planar view shape of the pair of circuit portions is a wave shape, the circuit portion convex on one side And the current generated in the circuit portion projecting to the other side cancel each other, and loss and heat generation in the circuit components can be effectively suppressed. Furthermore, the wavelength and amplitude in the wave shape can be appropriately set according to the size of the wiring board, and the space on the surface of the wiring board can be used efficiently.

  According to the third aspect of the present invention, since the shape of the pair of circuit parts in plan view is the figure eight shape, the currents generated in the two annular circuit parts forming the figure eight cancel each other. In addition, loss and heat generation in circuit components can be effectively suppressed.

  According to the invention described in claim 4, the two annular circuit portions are arranged so as to surround the opposite directions in the axial direction when the circuit portion pair is traced from one end to the other end. Currents generated in the two annular circuit portions cancel each other, and loss and heat generation in the circuit components can be effectively suppressed. Furthermore, for example, by providing one circuit portion on the front surface of the wiring board and providing the other circuit portion on the back surface, the wiring board can be formed smaller than a configuration in which two circuit portions are provided on one surface. The coil unit can be reduced in size.

  According to the fifth aspect of the present invention, the substrate body is disposed so as to face the end of the coil so that the axis of the coil and the thickness direction of the wiring board coincide with each other. It can arrange | position so that it may overlap with the edge part of this, and the enlargement of a coil unit can further be suppressed.

  According to the invention described in claim 6, as described above, it is possible to suppress the increase in size while suppressing the current flowing through the passage of the magnetic flux, and the power feeding system includes such a coil unit. It is possible to suppress a decrease in power supply efficiency and an increase in the size of the entire power supply system.

It is a side view showing the whole electric supply system concerning an embodiment of the present invention. It is a perspective view which shows the electric power feeding part of the electric power feeding system which concerns on 1st Embodiment. It is a top view which shows the circuit part of the electric power feeding part of FIG. It is a top view which shows the electric power feeding part of the electric power feeding system which concerns on 2nd Embodiment. It is a perspective view which shows the board | substrate body provided in the electric power feeding part of the electric power feeding system which concerns on 3rd Embodiment. It is a top view which shows the circuit part of the conventional electric power feeding system.

  Hereinafter, each embodiment of the present invention will be described with reference to the drawings. In the second and third embodiments, the same constituent members as those described in the first embodiment and the constituent members having the same functions are denoted by the same reference numerals as those in the first embodiment and the description thereof is omitted.

[First Embodiment]
The power feeding system 1 </ b> A of the first embodiment includes a power feeding unit 2 provided on the ground G such as a parking lot and a power receiving unit 3 provided on the vehicle V. The power feeding unit 2 is connected to an AC power source (not shown), the power receiving unit 3 is connected to the battery B, and power is supplied from the power feeding unit 2 to the power receiving unit 3 in a contactless manner via magnetic flux, thereby supplying the power feeding system 1A. Is configured such that the battery B can be charged from an AC power source. The power feeding unit 2 and the power receiving unit 3 have substantially the same configuration, and the configuration of the power feeding unit 2 will be described below.

  As shown in FIG. 2, the power feeding unit 2 includes a coil unit 20 including a coil 21, an iron core 22 around which the coil 21 is wound, and a substrate body 23 that is electrically connected to the coil 21. Has been.

  The coil 21 is configured such that the electric wire 211 is spirally wound around the iron core 22 with the direction orthogonal to the opposing direction of the power feeding unit 2 and the power receiving unit 3 as an axial direction. At the end, magnetic flux is generated in the axial direction. One end of the electric wire 211 is connected to an AC power source, and the other end is connected to a circuit unit 230 described later.

  The iron core 22 is made of ferrite, for example, and is formed in a flat plate shape extending in the axial direction of the coil 21 with the opposing direction as the plate thickness direction and the direction shown in FIG. Note that the iron core 22 may be omitted when the power supply efficiency from the power supply unit 2 to the power reception unit 3 is sufficiently high.

  The board body 23 includes a printed board 232 as a wiring board having a circuit pattern 231 formed on the surface 232a, and a plurality of capacitors 233 as circuit components mounted on the surface 232a of the printed board 232. The substrate body 23 is disposed so as to face the end portion of the coil 21 so that the axial direction of the coil 21 and the plate thickness direction of the printed circuit board 232 coincide with each other, and is superimposed on the end surface 22 a of the iron core 22. .

  In the substrate body 23, the circuit pattern 231 and the capacitor 233 constitute the circuit unit 230. The circuit unit 230 has one end connected to the coil 21 and the other end connected to an AC power source, and includes a plurality of series portions 234A and 234B connected in parallel to each other as shown in FIG. The left serial portion 234A in FIG. 3 includes a first circuit portion 235A and a second circuit portion 236A as two circuit portions connected in series with each other, and one set of two adjacent circuit portions 235A and 236A. The circuit part pair 237A is configured. 3 also includes a first circuit portion 235B and a second circuit portion 236B as two circuit portions connected in series with each other, and the two circuit portions 235B and 236B substantially A circuit part pair 237B is formed.

  The circuit part pair 237A, 237B has a rectangular wave shape in plan view, with the first circuit parts 235A, 235B and the second circuit parts 236A, 236B protruding in opposite directions. . In addition, the first circuit portions 235A and 235B and the second circuit portions 236A and 236B have substantially the same area as the portions surrounded by the convex shape.

  Next, the magnetic flux generated when current flows through the coil 21 connected to the AC power supply in the power feeding unit 2 as described above, and the current generated in the circuit unit 230 by this magnetic flux will be described. First, when an alternating current flows through the coil 21, an alternating magnetic flux is generated along the axial direction at the end of the coil 21, that is, the end surface 22 a of the iron core 22, and tries to pass through the substrate body 23.

  When this alternating magnetic flux passes through the inside of the circuit unit 230, an electromotive force is generated so as to prevent the magnetic flux from changing, and an electric current tends to flow through the circuit unit 230. Specifically, when the magnetic flux density in the direction from the back side to the near side in FIG. 3 increases, the currents I1 and I3 try to flow in the clockwise direction in the first circuit portions 235A and 235B, respectively. Currents I2 and I4 tend to flow through the circuit portions 236A and 236B in a clockwise direction, respectively. Furthermore, the currents I1 and I2 cancel each other, and the currents I3 and I4 cancel each other. That is, the generated currents cancel each other out in the first circuit portions 235A and 235B and the second circuit portions 236A and 236B that constitute the circuit portion pairs 237A and 237B and are adjacent to each other. Further, when the magnetic flux density in the direction from the front side to the back side of the paper increases, currents in directions opposite to the currents I1 to I4 flow through the circuit portion pairs 237A and 237B and cancel each other in substantially the same manner.

  According to this embodiment, there are the following effects. That is, since the currents generated in the first circuit portions 235A and 235B and the second circuit portions 236A and 236B cancel each other, the current flowing in the circuit unit 230 due to the passage of magnetic flux is suppressed, and the loss in the capacitor 233 due to this current is suppressed. And heat generation can be suppressed. That is, it is possible to suppress a decrease in power supply efficiency of the power supply system 1A. At this time, in the first circuit portions 235A and 235B and the second circuit portions 236A and 236B, the portions surrounded by the convex shape have substantially the same area, so that uniform magnetic flux is generated in the entire circuit portion 230. , The current I1 and the current I2 become substantially equal, and the current I3 and the current I4 become substantially equal, so that loss and heat generation in the capacitor 233 can be further suppressed.

  Furthermore, since the board | substrate body 23 is accumulated on the end surface 22a of the iron core 22, the enlargement of the coil unit 20 by providing the board | substrate body 23 and 1 A of electric power feeding systems provided with this can be suppressed. In particular, the coil unit 20 can be reduced in size in the axial direction as compared with the configuration in which the board body is disposed so that the plate thickness direction and the coil axial direction are orthogonal to each other so that the magnetic flux does not pass perpendicularly to the circuit. it can.

[Second Embodiment]
The power feeding system 1B of the second embodiment includes a power feeding unit 4 as shown in FIG. The power feeding unit 4 includes a coil unit 40 that includes a flat plate-shaped main body 41, a coil 42, and a substrate body 43 that is electrically connected to the coil 42.

  The coil 42 is formed in a spiral shape on the surface of the main body 41 with the opposing direction of the power feeding unit 4 and the power receiving unit 3 as an axial direction. When a current flows through the electric wire 421, the coil 42 is surrounded by the coil 42 on the main body 41. At the position, a magnetic flux is generated in the axial direction.

  The board body 43 includes a printed board 432 as a wiring board having a circuit pattern 431 formed on the surface 432a, and a plurality of capacitors 433 as circuit components mounted on the surface 432a of the printed board 432. Further, the substrate body 43 is overlaid on the main body 41 and disposed at a position surrounded by the coil 42 so that the axial direction of the coil 42 and the plate thickness direction of the printed circuit board 432 coincide.

  In the substrate body 43, the circuit pattern 431 and the capacitor 433 constitute a circuit unit 430. The circuit portion 430 includes a first circuit portion 435 and a second circuit portion 436 as two circuit portions connected in series with each other, and a pair of circuit portions is formed by the two adjacent circuit portions 435 and 436. Pair 437 is constructed.

  The plan view shape of the circuit portion pair 437 is formed in an 8-shape by forming the first circuit portion 435 and the second circuit portion 436 in an annular shape having substantially the same diameter. The circuit pattern 431 includes a first conductor portion 431A and a second conductor portion 431B that are vertically overlapped at a substantially central portion of the figure 8 and are insulated from each other, and the first circuit portion 435 and the second circuit portion. 435 is connected to the first conductor portion 431A.

  Next, the magnetic flux generated when current flows through the coil 42 connected to the AC power supply in the power feeding unit 4 as described above, and the current generated in the circuit unit 430 by this magnetic flux will be described. First, when an alternating current flows through the coil 42, an alternating magnetic flux along the axial direction is generated at a position surrounded by the coil 42, that is, at the substrate body 43.

  When this alternating magnetic flux passes through the inside of the circuit unit 430, an electromotive force is generated so as to prevent the magnetic flux from changing, and an electric current tends to flow through the circuit unit 430. Specifically, when the magnetic flux density in the direction from the back side to the front side in FIG. 4 increases, currents I5 and I6 flow through the first circuit portion 435 and the second circuit portion 436 in the clockwise direction, respectively. The electric wire I5 and the electric wire I6 cancel each other out in the first conductor portion 431A. Further, when the magnetic flux density in the direction from the front side to the back side of the paper increases, a current in the direction opposite to the currents I5 and I6 flows through the circuit portion pair 437 and cancels out in substantially the same manner.

  According to the present embodiment, the current flowing through the circuit unit 430 due to the passage of magnetic flux can be suppressed in substantially the same manner as in the first embodiment. Furthermore, since the substrate body 43 is overlaid on the main body 41 and is disposed at a position surrounded by the coil 42, it is possible to suppress an increase in size of the coil unit 40 and the power feeding system 1B including the coil unit 40. In particular, the coil unit 40 can be miniaturized in the facing direction as compared with the configuration in which the board body is disposed so that the plate thickness direction and the axial direction of the coil are orthogonal to each other so that the magnetic flux does not pass perpendicularly to the circuit. it can.

[Third Embodiment]
A power feeding system 1C according to the third embodiment includes a power feeding unit 5 having a substrate body 53 as shown in FIG. Note that the coil of the power feeding unit 5 may have a direction orthogonal to the facing direction to the power receiving unit 3 as in the first embodiment as an axial direction, or the facing direction as an axial direction as in the second embodiment. Good.

  The substrate body 53 includes a printed circuit board 532 as a wiring board having a circuit pattern 531 formed on the front surface 532a and the back surface 532b, and a plurality of capacitors 533 as circuit components mounted on the front surface 532a and the back surface 532b of the printed circuit board 532, Have Moreover, the board | substrate body 53 should just be arrange | positioned like 1st Embodiment or 2nd Embodiment with respect to a coil.

  In the substrate body 53, the circuit pattern 531 and the capacitor 533 constitute a circuit unit 530. The circuit portion 530 includes a first circuit portion 535 and a second circuit portion 536 as two circuit portions connected in series with each other, and a pair of circuit portions is formed by the two adjacent circuit portions 535 and 536. Pair 537 is constructed.

  The first circuit portion 535 and the second circuit portion 536 constituting the circuit portion pair 537 have an annular shape in plan view with the plate thickness direction of the printed circuit board 532 being the axial direction and having substantially the same diameter. The portion 535 is provided on the front surface 532a of the printed circuit board 532, and the second circuit portion 536 is provided on the back surface 532b, thereby overlapping in the plate thickness direction (axial direction). The first circuit portion 535 and the second circuit portion 536 are connected by a conductor portion 531A that penetrates the printed circuit board 532 in the plate thickness direction, and the axial direction when the circuit portion pair 537 is traced from one end to the other end. It is arranged so as to surround opposite each other.

  Next, the current generated in the circuit unit 530 by the magnetic flux generated when the current flows through the coil of the power supply unit 5 in the substrate body 53 as described above will be described. When the magnetic flux generated by the coil passes through the inside of the circuit unit 530, an electromotive force is generated so as to prevent the magnetic flux from changing, and an electric current tends to flow through the circuit unit 530. Specifically, when the magnetic flux density in the direction from the bottom to the top in FIG. 5 increases, currents I7 and I8 tend to flow through the first circuit portion 535 and the second circuit portion 536 in the clockwise direction, respectively. The electric wire I7 and the electric wire I8 cancel each other out at the conducting wire portion 531A. Further, when the magnetic flux density in the direction from the upper side to the lower side increases, a current in the direction opposite to the currents I7 and I8 flows through the circuit portion pair 537 and cancels out in substantially the same manner.

  According to such this embodiment, the electric current which flows into the circuit part 530 by passage of magnetic flux can be suppressed substantially like 1st Embodiment and 2nd Embodiment. Further, the first circuit portion 535 is provided on the front surface 532a of the printed circuit board 532 and the second circuit portion 536 is provided on the back surface 532b, so that the printed circuit board can be compared with a configuration in which two circuit parts are provided on one surface. The substrate body 53 can be reduced in size.

  In addition, this invention is not limited to the said 1st-3rd embodiment, The other modification etc. which can achieve the objective of this invention are included, and a deformation | transformation etc. which are shown below are also contained in this invention.

  For example, in the first to third embodiments, the planar view shape of the circuit portion pair is a wave shape, an 8-shaped shape, or an overlapped annular shape, but these shapes are appropriately combined. The two circuit parts constituting the circuit part pair may be arranged so that the generated currents cancel each other. Further, the plan view shape of the circuit portion pair and the circuit portion may be a shape in which straight lines and curves are appropriately combined. For example, in the case of a wave shape, it may be a sine wave or a triangular wave instead of a rectangular wave. In the case of an annular shape, it is not limited to a circular ring, and may be a polygonal ring.

  In the first and second embodiments, the substrate body is disposed to face the end of the coil so that the axis of the coil and the thickness direction of the wiring board coincide with each other. Depending on the shape and installation position of the coil unit, the plate thickness direction may be oriented in an appropriate direction and disposed at an appropriate position.

  In the first embodiment, the first circuit portions 235A and 235B and the second circuit portions 236A and 236B have substantially the same area in the portions surrounded by the convex shape, and the second and third embodiments In the embodiment, the first circuit portions 435 and 535 and the second circuit portions 436 and 536 have substantially the same diameter. However, the area between the portion surrounded by the first circuit portion and the portion surrounded by the second circuit portion. The ratio only needs to be set appropriately according to the distribution of the passing magnetic flux so that the generated currents sufficiently cancel each other.

  In the first to third embodiments, the power feeding unit and the power receiving unit have substantially the same configuration, but the power feeding unit and the power receiving unit may have different configurations, at least one of which is What is necessary is just to provide the above substrate bodies.

  In the first to third embodiments, the power feeding systems 1A to 1C for charging the vehicle are exemplified. However, the power feeding system may be any one that supplies power in a non-contact manner, such as a mobile phone. It may be for charging an electronic device.

  In addition, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations. Therefore, the description limiting the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

1A, 1B, 1C Power feeding system 2, 4, 5 Power feeding unit 3 Power receiving unit 21, 42 Coil 23, 43, 53 Board body 231, 431, 531 Circuit pattern 232, 432, 532 Printed circuit board (wiring board)
233, 433, 533 Capacitors (circuit parts)
230, 430, 530 Circuit part 235A, 235B, 435, 535 First circuit part 236A, 236B, 436, 536 Second circuit part 237A, 237B, 437, 537 Circuit part pair

Claims (6)

A coil unit used in the power feeding unit or the power receiving unit in a power feeding system that supplies power in a non-contact manner from the power feeding unit to the power receiving unit,
Coils,
A circuit board having a circuit board on which a circuit pattern is formed and a circuit component mounted on the circuit board, and a circuit unit configured by the circuit pattern and the circuit component is electrically connected to the coil; With
The circuit unit includes a plurality of circuit parts connected in series with each other, and at least one circuit part pair configured by two adjacent circuit parts arranged so that currents generated by magnetic flux cancel each other out. A coil unit comprising a set.   2. The coil unit according to claim 1, wherein the shape of the circuit portion pair in plan view is such that the two circuit portions are convex in opposite directions and the entire shape is a wave shape.   2. The coil unit according to claim 1, wherein a shape of the circuit portion pair in plan view is an 8-shaped shape. The planar view shape of each of the two circuit parts of the circuit part pair is an annular shape whose axial direction is the thickness direction of the wiring board,
The two circuit portions are overlapped in the plate thickness direction, and are arranged so as to surround the axial directions in opposite directions when the circuit portion pair is traced from one end to the other end. The coil unit according to claim 1.   The said board | substrate body is arrange | positioned facing the edge part of the said coil so that the axis | shaft of the said coil and the plate | board thickness direction of the said wiring board may correspond, The any one of Claims 1-4 characterized by the above-mentioned. The coil unit according to item. A power supply system that supplies electric power from a power supply unit to a power reception unit in a contactless manner,
At least one of the power reception unit and the power supply unit includes the coil unit according to any one of claims 1 to 5.

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