Resonant capacitor module, contactless power transfer system, and vehicle

Abstract

To provide a resonant capacitor module, a contactless power transfer system, and a vehicle that can suppress magnetic radiation, thereby contributing to energy efficiency.SOLUTION: A resonant capacitor module includes a coil portion, a substrate portion electrically connected to the coil portion, and a power conversion portion electrically connected to the substrate portion, and the substrate portion includes a first conductor portion on which a first group of resonant capacitors is mounted, and a second conductor portion on which a second group of resonant capacitors is mounted, the second conductor portion is positioned adjacent to the first conductor portion and through which current flows in the opposite direction to that of the first conductor portion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resonant capacitor module, a contactless power transfer system, and a vehicle. [Background technology]

[0002] In recent years, research and development into secondary batteries that contribute to energy efficiency has been conducted to ensure that more people have access to affordable, reliable, sustainable and advanced energy. Patent Document 1 below discloses a wireless power transmission system that charges a battery (secondary battery) mounted on an electric vehicle such as an electric car. This wireless power transmission system includes two resonators that perform wireless power transmission using a magnetic field resonance method, and each resonator includes a resonance circuit including a coil and a capacitor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-87593 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned resonators handle high voltage and high frequency power, and therefore magnetic radiation, which can be a source of electromagnetic interference, is a problem.

[0005] In order to solve the above-mentioned problems, the present application aims to provide a resonant capacitor module, a contactless power transfer system, and a vehicle that can suppress magnetic radiation, which will ultimately contribute to improving energy efficiency. [Means for solving the problem]

[0006] The resonant capacitor module, the contactless power transfer system, and the vehicle according to the present invention employ the following configurations. (1): A resonant capacitor module according to one embodiment of the present invention comprises a coil section, a substrate section electrically connected to the coil section, and a power conversion section electrically connected to the substrate section, wherein the substrate section comprises a first conductor section on which a first group of resonant capacitors is mounted, and a second conductor section on which a second group of resonant capacitors is mounted, the second conductor section being disposed adjacent to the first conductor section and through which a current flows in the opposite direction to that of the first conductor section.

[0007] (2): In the above aspect (1), the coil portion may have one end electrically connected to the first conductor portion, and the other end arranged adjacent to the one end, extending parallel to the one end, and electrically connected to the second conductor portion.

[0008] (3): In the above aspect (1) or (2), the power conversion unit may include a first switch unit electrically connected to the first conductor unit, and a second switch unit arranged adjacent to the first switch unit and electrically connected to the second conductor unit.

[0009] (4): In the above aspects (1) to (3), the first conductor portion including the first resonant capacitor group and the second conductor portion including the second resonant capacitor group may be provided on both sides of the substrate portion.

[0010] (5): In the above aspect (1), the substrate portion may include a third conductor portion that electrically connects the first conductor portion and the second conductor portion.

[0011] (6): In the above aspect (5), the substrate portion may include a first substrate portion electrically connected to one end of the coil portion and including the first conductor portion, the second conductor portion, and the third conductor portion, and a second substrate portion electrically connected to the other end of the coil portion and including the first conductor portion, the second conductor portion, and the third conductor portion.

[0012] (7) A contactless power transfer system according to one aspect of the present invention includes the resonant capacitor module according to any one of the above aspects (1) to (6).

[0013] (8) A vehicle according to one aspect of the present invention includes the resonant capacitor module according to any one of the above aspects (1) to (6). [Effects of the Invention]

[0014] According to the above aspect, the first conductor portion on which the first resonant capacitor group is mounted and the second conductor portion on which the second resonant capacitor group is mounted are disposed adjacent to each other and currents flow in opposite directions, so that the magnetic fields generated in the first conductor portion and the second conductor portion cancel each other out, thereby suppressing magnetic radiation from the resonant capacitor module. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a plan view of a resonant capacitor module according to a first embodiment. [Figure 2] 1 is a cross-sectional view of a resonant capacitor module according to a first embodiment. [Figure 3] FIG. 1 is a circuit diagram of a resonant capacitor module according to a first embodiment. [Figure 4] 5A to 5C are diagrams illustrating the operation of the resonant capacitor module according to the first embodiment. [Figure 5] FIG. 10 is a cross-sectional view of a resonant capacitor module according to a second embodiment. [Figure 6] FIG. 10 is a plan view of a resonant capacitor module according to a third embodiment. [Figure 7] FIG. 10 is a cross-sectional view of a resonant capacitor module according to a third embodiment. [Figure 8] FIG. 10 is a schematic configuration diagram of a contactless power transfer system according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0017] (First embodiment) Fig. 1 is a plan view of a resonant capacitor module 10 according to a first embodiment. Fig. 2 is a cross-sectional view of the resonant capacitor module 10 according to the first embodiment. Fig. 3 is a circuit diagram of the resonant capacitor module 10 according to the first embodiment. As shown in these figures, the resonant capacitor module 10 comprises a coil section 20, a substrate section 30 electrically connected to the coil section 20, and a power conversion section 40 electrically connected to the substrate section 30.

[0018] In the following description, an XYZ Cartesian coordinate system is set, and the positional relationship of each component is sometimes described with reference to this XYZ Cartesian coordinate system. The X-axis direction is a first horizontal direction. The Y-axis direction is a second horizontal direction that is perpendicular to the first horizontal direction. The Z-axis direction is a vertical direction that is perpendicular to the first and second horizontal directions.

[0019] As shown in Fig. 2, the substrate unit 30 and the power conversion unit 40 are housed inside a metal case 50. The metal case 50 includes a bottom case 51 and an upper cover 52. The bottom case 51 is formed in the shape of a box with a bottom that is open at the top. The upper cover 52 is formed in the shape of a flat plate that closes the top opening of the bottom case 51, and is screwed to the edge of the top opening of the bottom case 51.

[0020] The power conversion unit 40 is disposed at the bottom of the bottom case 51. A heat dissipation structure 53 is attached to the underside of the power conversion unit 40. The heat dissipation structure 53 has a plurality of heat dissipation fins that protrude outside the metal case 50. The heat dissipation structure 53 is fixed to the bottom opening of the bottom case 51 with screws.

[0021] The substrate 30 is supported in a horizontal position inside the metal case 50. The substrate 30 is attached to a base provided at the bottom of the bottom case 51. The substrate 30 is, for example, a printed circuit board, and has a generally rectangular shape extending in the X-axis direction. As shown in FIG. 1, a first conductor 31A and a second conductor 31B are formed on an upper surface 30a of the substrate 30.

[0022] The first conductor 31A is a conductor pattern extending in the X-axis direction, and has the first resonant capacitor group 32A mounted thereon. Specifically, the first conductor 31A has a first portion electrically connected to the coil 20 at its end on the +X side, a second portion connected to the power converter 40 at its end on the -X side, and a third portion connecting the first portion and the second portion.

[0023] The third section is composed of a plurality of conductor patterns that extend parallel to the X-axis direction at intervals in the Y-axis direction, and a plurality of resonant capacitors (first resonant capacitor group 32A) are mounted on each of these conductor patterns. The first and second sections function as bus bars that distribute power to the first resonant capacitor group 32A.

[0024] The second conductor portion 31B is disposed adjacent to the first conductor portion 31A in the Y-axis direction and extends parallel to the first conductor portion 31A in the X-axis direction. The second conductor portion 31B is a conductor pattern extending in the X-axis direction, and has the second resonant capacitor group 32B mounted thereon. Specifically, the second conductor portion 31B has a first portion electrically connected to the coil portion 20 at an end on the +X side, a second portion connected to the power conversion portion 40 at an end on the -X side, and a third portion connecting the first portion and the second portion.

[0025] The third section is composed of a plurality of conductor patterns that extend parallel to the X-axis direction at intervals in the Y-axis direction, and a plurality of resonant capacitors (second resonant capacitor group 32B) are mounted on each of these conductor patterns. The first and second sections function as bus bars that distribute power to the second resonant capacitor group 32B.

[0026] 1 and 2, and one end 21 and the other end 22 extending from the winding body. The one end 21 of the coil portion 20 is electrically connected to a first portion on the +X side of the first conductor portion 31A via a contact member 61. The other end 22 of the coil portion 20 is electrically connected to a first portion on the +X side of the second conductor portion 31B via a contact member 62.

[0027] One end 21 of the coil portion 20 extends in the Y-axis direction and is disposed on the lower surface 30b side of the substrate portion 30 (see FIG. 2). The other end 22 of the coil portion 20 is also disposed on the lower surface 30b side of the substrate portion 30. As shown in FIG. 1, the other end 22 of the coil portion 20 is disposed adjacent to the one end 21 in the X-axis direction and extends parallel to the one end 21 in the Y-axis direction. The contact members 61, 62 are disposed offset in the X-axis direction.

[0028] The power conversion unit 40 includes a first switch unit 41 and a second switch unit 42. The first switch unit 41 is electrically connected to a second portion on the -X side of the first conductor portion 31A via a pair of contact members 63. The first switch unit 41 includes a pair of DC connection terminals 41a.

[0029] The second switch section 42 is electrically connected to a second portion on the -X side of the second conductor section 31B via a pair of contact members 64. The second switch section 42 includes a pair of DC connection terminals 42a. The second switch section 42 is disposed adjacent to the first switch section 41 in the Y-axis direction.

[0030] 3, the first switch unit 41 and the second switch unit 42 each include a switching element (power semiconductor) and a free wheel diode in the upper arm and the lower arm, respectively. The power conversion unit 40 includes the first switch unit 41, the second switch unit 42, and a smoothing capacitor 43, and forms an inverter circuit that converts DC power to AC power. Note that the power conversion unit 40 may form a converter circuit that converts AC power to DC power, or may further include a switch unit to form both an inverter circuit and a converter circuit.

[0031] When AC power is supplied from the power conversion unit 40 to the coil unit 20, currents flow in opposite directions through one end 21 of the coil unit 20, the first conductor unit 31A, and the first switch unit 41, and the other end 22 of the coil unit 20, the second conductor unit 31B, and the second switch unit 42, as shown in Fig. 1. Fig. 1 shows that current A1 flows from the -X side to the +X side of the first conductor unit 31A, and current A2 flows from the +X side to the -X side of the second conductor unit 31B. The directions of currents A1 and A2 alternate.

[0032] FIG. 4 is a diagram illustrating the operation of the resonant capacitor module 10 according to the first embodiment. 4, one end 21 of the coil section 20, the first conductor section 31A, and the first switch section 41 and the other end 22 of the coil section 20, the second conductor section 31B, and the second switch section 42 are arranged adjacent to each other, and currents flow in opposite directions. As a result, the magnetic fields generated by the one end 21 of the coil section 20, the first conductor section 31A, and the first switch section 41 and the magnetic fields generated by the other end 22 of the coil section 20, the second conductor section 31B, and the second switch section 42 cancel each other out. Therefore, magnetic radiation from the resonant capacitor module 10 can be suppressed.

[0033] As described above, the resonant capacitor module 10 includes the coil section 20, the substrate section 30 electrically connected to the coil section 20, and the power conversion section 40 electrically connected to the substrate section 30. The substrate section 30 includes the first conductor section 31A on which the first resonant capacitor group 32A is mounted, and the second conductor section 31B on which the second resonant capacitor group 32B is mounted, the second conductor section 31B being disposed adjacent to the first conductor section 31A, and through which a current flows in the opposite direction to that in the first conductor section 31A. With this configuration, the magnetic fields generated by the first conductor section 31A and the second conductor section 31B cancel each other out, thereby suppressing magnetic radiation from the resonant capacitor module 10.

[0034] Moreover, in this embodiment, the coil section 20 includes one end 21 electrically connected to the first conductor section 31A, and the other end 22 disposed adjacent to the one end 21, extending parallel to the one end 21, and electrically connected to the second conductor section 31B. With this configuration, the magnetic fields generated at the one end 21 of the coil section 20 and the magnetic fields generated at the other end 22 of the coil section 20 cancel each other out, thereby suppressing magnetic radiation from the resonant capacitor module 10.

[0035] In this embodiment, the power conversion unit 40 includes a first switch unit 41 electrically connected to the first conductor unit 31A, and a second switch unit 42 disposed adjacent to the first switch unit 41 and electrically connected to the second conductor unit 31B. With this configuration, the magnetic fields generated by the first switch unit 41 and the second switch unit 42 cancel each other out, thereby suppressing magnetic radiation from the resonant capacitor module 10.

[0036] (Second embodiment) Next, a second embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiment will be denoted by the same reference numerals, and the description thereof will be simplified or omitted.

[0037] FIG. 5 is a cross-sectional view of a resonant capacitor module 10 according to the second embodiment. 5, in the second embodiment, a first conductor 31A including a second resonant capacitor group 32B and a second conductor 31B including a second resonant capacitor group 32B are provided on both the upper surface 30a and the lower surface 30b of the substrate 30. This configuration makes it possible to increase the integration density of multiple resonant capacitors on the substrate 30 while suppressing magnetic radiation. In other words, it is possible to reduce the area of ​​the substrate 30 or increase the capacitance of the resonant capacitors.

[0038] (Third embodiment) Next, a third embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiment will be denoted by the same reference numerals, and the description thereof will be simplified or omitted.

[0039] Fig. 6 is a plan view of the resonant capacitor module 10 according to the third embodiment, and Fig. 7 is a cross-sectional view of the resonant capacitor module 10 according to the third embodiment. As shown in these figures, in the third embodiment, the substrate section 30 includes a first substrate section 30A and a second substrate section 30B.

[0040] The first substrate portion 30A includes a first conductor portion 31A on which a first resonant capacitor group 32A is mounted, a second conductor portion 31B on which a second resonant capacitor group 32B is mounted, which is arranged adjacent to the first conductor portion 31A and through which current flows in the opposite direction to that of the first conductor portion 31A, and a third conductor portion 31C that electrically connects the first conductor portion 31A and the second conductor portion 31B.

[0041] In the first substrate unit 30A, the first conductor 31A extends in the X-axis direction. The +X side end of this first conductor 31A is electrically connected to one end 21 of the coil unit 20 via a contact member 61. In addition, in the first substrate unit 30A, the second conductor 31B is disposed adjacent to the first conductor 31A in the Y-axis direction and extends in the X-axis direction parallel to the first conductor 31A.

[0042] The third conductor portion 31C extends in the Y-axis direction and electrically connects the -X side end of the first conductor portion 31A and the -X side end of the second conductor portion 31B. That is, the conductor pattern of the first substrate portion 30A is formed in a U-shape in plan view. The +X side end of the second conductor portion 31B is electrically connected to the first switch portion 41 disposed below the first substrate portion 30A via a contact member 63, as shown in FIG.

[0043] 6, the second substrate unit 30B has a symmetrical structure to the first substrate unit 30A. The second substrate unit 30B includes a first conductor 31A on which a first resonant capacitor group 32A is mounted, a second conductor 31B on which a second resonant capacitor group 32B is mounted, the second conductor 31B being disposed adjacent to the first conductor 31A and through which a current flows in the opposite direction to that in the first conductor 31A, and a third conductor 31C electrically connecting the first conductor 31A and the second conductor 31B.

[0044] In the second substrate unit 30B, the first conductor 31A extends in the X-axis direction. The -X side end of this first conductor 31A is electrically connected to the other end 22 of the coil unit 20 via a contact member 62. In addition, in the second substrate unit 30B, the second conductor 31B is disposed adjacent to the first conductor 31A in the Y-axis direction and extends in the X-axis direction parallel to the first conductor 31A.

[0045] The third conductor portion 31C extends in the Y-axis direction and electrically connects the +X side end of the first conductor portion 31A and the +X side end of the second conductor portion 31B. That is, the conductor pattern of the second substrate portion 30B is formed in a U-shape in plan view. The -X side end of the second conductor portion 31B is electrically connected to the second switch portion 42 arranged below the second substrate portion 30B via a contact member 64, as shown in FIG.

[0046] According to the above configuration, in each of the first substrate portion 30A and the second substrate portion 30B, the first conductor portion 31A and the second conductor portion 31B are adjacent to each other and currents flow in opposite directions, so that the magnetic fields generated in the first conductor portion 31A and the second conductor portion 31B cancel each other out, thereby suppressing magnetic radiation from the resonant capacitor module 10.

[0047] As a modification of the third embodiment, magnetic radiation from the resonant capacitor module 10 can be suppressed by forming a conductor pattern in a similar U-shape even with a single substrate unit 30. This eliminates the need to place resonant capacitors on both sides of the coil unit 20, as shown in Fig. 3, and allows the resonant capacitor to be placed on one side of the coil unit 20.

[0048] (Fourth embodiment) Next, a fourth embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiments will be denoted by the same reference numerals, and the description thereof will be simplified or omitted.

[0049] FIG. 8 is a schematic configuration diagram of a contactless power transfer system 100 according to the fourth embodiment. As shown in FIG. 8, the contactless power transfer system 100 includes a power receiving device 8 including the resonant capacitor module 10 described above, and a power feeding device 9 that supplies power to the power receiving device 8.

[0050] The power receiving device 8 is provided in a vehicle 1. The vehicle 1 is, for example, an electric vehicle, and is equipped with a traction motor 2. The driving force of the traction motor 2 is transmitted to left and right drive wheels 4, 4 via gears (not shown). The traction motor 2 is, for example, a DC brushless motor, and is electrically connected to the power storage device 6 via a control device (not shown).

[0051] The power storage device 6 is disposed under the rear seat or near the floor panel, and is electrically connected to a power receiving device 8 that performs contactless charging. The power receiving device 8 is attached under the floor, such as on the underside of the floor panel, and charges the power storage device 6 by converting the received AC power into DC power using, for example, a magnetic resonance method.

[0052] The power supply device 9 is installed in a parking lot or the like, and charges the power storage device 6 by contactless charging. The coil portion of the power supply device 9 is buried, for example, in the ground (road surface) of the parking area. When the power receiving device 8 and the power supply device 9 are arranged opposite each other and an AC current is passed through the coil portion of the power supply device 9, the AC current flows through the coil portion 20 of the power receiving device 8, and the power storage device 6 can be charged. According to the contactless power transfer system 100 and the vehicle 1 configured as described above, since the resonant capacitor module 10 is provided, magnetic radiation that can be a source of electromagnetic interference can be suppressed.

[0053] While preferred embodiments of the present invention have been described and illustrated, it should be understood that these are illustrative of the present invention and should not be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the present invention. Accordingly, the present invention should not be deemed limited by the foregoing description, but rather by the scope of the claims. [Explanation of symbols]

[0054] 1 vehicle 2. Travel motor 4 drive wheels 6. Energy storage device 8 Power Receiving Device 9 Power supply equipment 10 Resonant Capacitor Module 20 Coil section 21 One end 22 Other end 30 Circuit Board 30a top surface 30A First board section 30b Bottom side 30B 2nd board part 31A First conductor 31B Second conductor part 31C Third conductor 32A 1st resonant capacitor group 32B Second resonant capacitor group 40 Power conversion section 41 First switch section 41a DC connection terminal 42 Second switch section 42a DC connection terminal 43 Smoothing capacitor 50 Metal Case 51 Bottom case 52 Upper cover 53 Heat dissipation structure 61 Contact parts 62 Contact parts 63 Contact parts 64 Contact parts 100 Contactless power transmission system A1 current A2 current

Claims

1. A coil portion; a substrate portion electrically connected to the coil portion; a power conversion unit electrically connected to the substrate unit, The substrate portion is a first conductor portion on which a first resonant capacitor group is mounted; a second conductor portion on which a second resonant capacitor group is mounted, the second conductor portion being disposed adjacent to the first conductor portion and through which a current flows in a direction opposite to that of the first conductor portion; Resonant capacitor module.

2. The coil portion One end electrically connected to the first conductor portion; and an other end portion disposed adjacent to the one end portion, extending parallel to the one end portion, and electrically connected to the second conductor portion.

2. The resonant capacitor module of claim 1.

3. The power conversion unit a first switch portion electrically connected to the first conductor portion; a second switch section disposed adjacent to the first switch section and electrically connected to the second conductor section; 3. The resonant capacitor module according to claim 1 or 2.

4. the first conductor portion including the first resonant capacitor group and the second conductor portion including the second resonant capacitor group are provided on both surfaces of the substrate portion; 3. The resonant capacitor module according to claim 1 or 2.

5. the substrate portion includes a third conductor portion that electrically connects the first conductor portion and the second conductor portion; 2. The resonant capacitor module of claim 1.

6. The substrate portion includes: a first substrate portion electrically connected to one end of the coil portion and including the first conductor portion, the second conductor portion, and the third conductor portion; a second substrate portion electrically connected to the other end of the coil portion and including the first conductor portion, the second conductor portion, and the third conductor portion; 6. The resonant capacitor module according to claim 5.

7. A contactless power transfer system comprising the resonant capacitor module according to claim 1 or 2.

8. A vehicle comprising the resonant capacitor module according to claim 1 or 2.

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