JP6217435B2 - Power receiving device - Google Patents

Description

  The present invention relates to a power receiving device that receives power from a power transmitting device in a contactless manner.

  As disclosed in Patent Documents 1 to 6 below, a power receiving device that receives power from a power transmitting device in a contactless manner is known. Generally, a power receiving device and a power transmitting device include a ferrite core, a spiral coil disposed on the surface of the ferrite core, and a capacitor electrically connected to the coil to form a so-called donut-shaped magnetic field. By doing so, power can be transmitted and received.

JP 2011-258807 A JP2013-154815A JP2013-146154A JP2013-146148A JP 2013-110822 A JP 2013-126327 A

  With respect to the arrangement of the capacitors, when the capacitors and the coils are arranged at positions adjacent to each other in the horizontal direction (for example, the horizontal direction), the size in the horizontal direction of the entire device increases. On the other hand, when the capacitor is arranged at the position on the back side of the ferrite core, the thickness of the entire device increases. An object of this invention is to provide the power receiving apparatus which can suppress the enlargement of an apparatus.

  A power receiving device that receives power in a contactless manner from the power transmitting device while facing the power transmitting device, the power receiving device being formed on a side opposite to the first main surface and the first main surface, the power receiving device facing the power transmitting device And a second main surface located farther from the power transmission device than the first main surface, and a convex portion is formed on the first main surface, opposite to the convex portion on the second main surface. A ferrite core having a recess formed at a side position, a coil having a spiral shape and arranged to surround the projection on the first main surface, and a capacitor electrically connected to the coil The height of the convex portion from the first main surface substantially matches the coil height in the winding axis direction of the coil, and the capacitor is accommodated in the concave portion. .

  According to said structure, since the height from the 1st main surface of a convex part corresponds substantially with coil height, the surface of a convex part and the surface of a coil have the substantially flush relationship. Can be formed. Furthermore, since the capacitor is accommodated in the recess, the capacitor is prevented from protruding from the position where the ferrite core is disposed. Therefore, since the thickness of the power receiving device can be made closer to the thickness of the ferrite core as compared to the conventional case, the increase in size of the device due to the provision of the capacitor can be suppressed.

It is a figure which shows the electric power transmission system in embodiment. It is a top view which shows the power receiving apparatus in embodiment. It is arrow sectional drawing along the III-III line in FIG. It is a top view which shows the power receiving apparatus in a comparative example. It is arrow sectional drawing along the VV line in FIG.

  Hereinafter, embodiments will be described with reference to the drawings. When referring to the number and amount, the scope of the present invention is not necessarily limited to the number and amount unless otherwise specified. The same parts and corresponding parts are denoted by the same reference numerals, and redundant description may not be repeated.

(Power transmission system 1000)
A power transmission system 1000 that transmits power without contact will be described with reference to FIG. 1. The power transmission system 1000 includes an electric vehicle 100 and an external power feeding device 300. Electric vehicle 100 includes a vehicle main body 110 and a power receiving device 200. The vehicle main body 110 includes a vehicle ECU 120, a rectifier 130, a DC / DC converter 140, a battery 150, a power control unit 160, a motor unit 170, a communication unit 180, and the like.

  The power receiving device 200 receives power from the power transmitting device 400 in a contactless manner while facing the power transmitting device 400 of the external power feeding device 300. Specifically, the power receiving device 200 includes a power receiving unit 210 and a housing (not shown) that houses the power receiving unit 210. The power receiving unit 210 includes a capacitor 220 and a coil unit 230 (ferrite core 240 and power receiving coil 250). Including. The power receiving coil 250 and the capacitor 220 are connected in series, but they may be connected in parallel. The number of turns of power reception coil 250 is the distance between power reception coil 250 and power transmission coil 450, the Q value (for example, Q ≧ 100) indicating the resonance strength between power reception coil 250 and power transmission coil 450, and the coupling coefficient indicating the degree of coupling. It is appropriately set so that κ and the like become large.

  The external power supply device 300 includes a power transmission device 400, a high frequency power device 310, a power transmission ECU 320, and a communication unit 322. High-frequency power device 310 is connected to AC power supply 330 and power transmission device 400. The power transmission device 400 includes a power transmission unit 410 and a housing (not shown) that houses the power transmission unit 410, and the power transmission unit 410 includes a capacitor 420 and a coil unit 430 (ferrite core 440 and power transmission coil 450). Although the power transmission coil 450 and the capacitor 420 are connected in series, they may be connected in parallel. The high frequency power device 310 converts the power received from the AC power source 330 into high frequency power, and supplies the converted high frequency power to the power transmission coil 450. The power transmission coil 450 transmits power to the power reception coil 250 of the power reception unit 210 in a non-contact manner by electromagnetic induction.

(Power receiving device 200)
FIG. 2 is a plan view showing the power receiving device 200. 3 is a cross-sectional view taken along the line III-III in FIG. As described above, power reception device 200 in the present embodiment includes power reception unit 210 and a housing (not shown) that houses power reception unit 210. The power receiving unit 210 includes a capacitor 220 and a coil unit 230, and the coil unit 230 has a ferrite core 240 and a power receiving coil 250 (coil).

  The ferrite core 240 has a so-called lid shape as a whole, and is arranged so as to be substantially parallel to the horizontal direction. Ferrite core 240 includes a first main surface 241 and a second main surface 242 formed on the opposite side of first main surface 241. The first main surface 241 and the second main surface 242 are both part of the portion constituting the surface of the ferrite core 240, and when the power receiving device 200 faces the power transmitting device 400, the second main surface 242 Is located farther from the power transmission device 400 than the first main surface 241.

  On the first main surface 241, a convex portion 243 having a shape such that a part of the first main surface 241 protrudes toward the power transmission device 400 is formed. The second main surface 242 is formed with a recess 244 having a shape such that a part of the second main surface 242 is recessed toward the power transmission device 400 (first main surface 241). Concave portion 244 is located on the opposite side of convex portion 243 on second main surface 242. The power receiving coil 250 has a spiral shape and is disposed on the first main surface 241 so as to surround the convex portion 243.

  Referring to FIG. 3, height H <b> 1 (projection height) from first main surface 241 of convex portion 243 substantially matches coil height D <b> 1 in the winding axis direction of power receiving coil 250. The “coil height D1 in the winding axis direction” refers to the distance from the first main surface 241 to the portion of the power receiving coil 250 arranged on the first main surface 241 that is closest to the power transmission device 400. It is. The coil height D1 in the winding axis direction is equal to the coil diameter, for example, when the power receiving coil 250 has a so-called single winding shape that does not overlap in the coil winding axis direction. When it is laminated and wound so as to overlap in the direction of the rotation axis, it is equal to the coil diameter x the number of turns.

  The technical range of the idea of “substantially coincidence” here includes an inequality of (0.9 × projection height H1) ≦ coil height D1 ≦ (1.1 × projection height H1), and (0 .9 × coil height D1) ≦ projection height H1 ≦ (1.1 × coil height D1) includes a case where a relationship that satisfies at least one of the inequalities is established. The ferrite core 240 satisfying such a configuration may be configured by combining a plurality of ferrites having a block shape, or may be configured from a single ferrite.

  The capacitor 220 is electrically connected to the power receiving coil 250 by a wiring member (not shown) and is accommodated in the recess 244. The technical scope of the idea that the capacitor 220 is accommodated in the recess 244 is not limited to the case where the entire capacitor 220 is located in the space formed inside the recess 244, and the capacitor 220 is in that space. The case where at least a part of is located is also included. It is preferable that the depth dimension T1 of the recess 244 from the second main surface 242 is equal to or greater than the height dimension C1 of the capacitor 220. The position of the outer end surface 220T of the capacitor 220 is flush with the second main surface 242 or is located closer to the first main surface 241 than the second main surface 242 (side closer to the first main surface 241). Preferably it is.

(Power transmission device 400)
Referring to FIG. 3, power transmission device 400 of the present embodiment has a configuration substantially similar to that of power reception device 200. Specifically, the power transmission device 400 includes a power transmission unit 410 and a housing (not shown) that houses the power transmission unit 410. The power transmission unit 410 includes a capacitor 420 and a coil unit 430, and the coil unit 430 has a ferrite core 440 and a power transmission coil 450 (coil).

  The ferrite core 440 has a so-called lid shape as a whole, and is arranged so as to be substantially parallel to the horizontal direction. Ferrite core 440 includes a first main surface 441 and a second main surface 442 formed on the opposite side of first main surface 441. The first main surface 441 and the second main surface 442 are both part of the portion constituting the surface of the ferrite core 440, and when the power transmission device 400 faces the power reception device 200, the second main surface 442 Is located farther from the power receiving device 200 than the first main surface 441.

  A convex portion 443 having a shape such that a part of the first main surface 441 protrudes toward the power receiving device 200 is formed on the first main surface 441. The second main surface 442 is formed with a recess 444 having a shape in which a part of the second main surface 442 is recessed toward the power receiving device 200 (first main surface 441). Concave portion 444 is located on the opposite side of convex portion 443 on second main surface 442. The power transmission coil 450 has a spiral shape and is disposed on the first main surface 441 so as to surround the periphery of the convex portion 443.

  Referring to FIG. 3, height H <b> 2 (projection height) of first protrusion 443 from first main surface 441 substantially matches coil height D <b> 2 in the winding axis direction of power transmission coil 450. The “coil height D2 in the winding axis direction” refers to the distance from the first main surface 441 to the portion of the power transmission coil 450 arranged on the first main surface 441 that is closest to the power receiving device 200. It is. The coil height D2 in the winding axis direction is equal to the coil diameter when the power transmission coil 450 has a so-called single winding shape that does not overlap in the coil winding axis direction. When it is laminated and wound so as to overlap in the direction of the rotation axis, it is equal to the coil diameter x the number of turns.

  The technical scope of the idea of “substantially coincidence” here includes an inequality of (0.9 × projection height H2) ≦ coil height D2 ≦ (1.1 × projection height H2), and (0 .9 × coil height D2) ≦ projection height H2 ≦ (1.1 × coil height D2) includes a case where a relationship satisfying at least one of the inequalities is established. The ferrite core 440 satisfying such a configuration may be configured by combining a plurality of ferrites having a block shape, or may be configured from a single ferrite.

  Capacitor 420 is electrically connected to power transmission coil 450 by a wiring member (not shown) and is accommodated in recess 444. The technical scope of the idea that the capacitor 420 is accommodated in the recess 444 is not limited to the case where the entire capacitor 420 is located in the space formed inside the recess 444, and the capacitor 420 is in that space. The case where at least a part of is located is also included. The depth dimension T2 from the second main surface 442 of the recess 444 is preferably equal to or greater than the height dimension C2 of the capacitor 420. The position of the outer end surface 420T of the capacitor 420 is flush with the second main surface 442, or is positioned closer to the first main surface 441 than the second main surface 442 (side closer to the first main surface 441). Preferably it is.

(Function and effect)
Since the protruding height H1 of the convex portion 243 from the first main surface 241 substantially matches the coil height D1, the surface of the tip portion in the protruding direction of the convex portion 243 and the surface of the power receiving coil 250 are substantially the same. In general, a flush relationship can be formed. Furthermore, since the capacitor 220 is accommodated in the recess 244, the capacitor 220 is prevented from protruding from the position where the ferrite core 240 is disposed (second main surface 242).

  Therefore, it is possible to make the thickness of the power receiving device 200 close to the thickness of the ferrite core 240 as compared with the conventional case, and the increase in size of the device due to the provision of the capacitor 220 can be suppressed. Here, the thickness of the ferrite core 240 is a dimension from the second main surface 242 to the tip in the protruding direction of the convex part 243, and is a value indicated by a dimension A1 in FIG. The dimension A1 (the thickness of the ferrite core 240) can be substantially the same as the value obtained by adding the coil height D1 of the power receiving coil 250 to the dimension A2 from the second main surface 242 to the first main surface 241. is there.

  Furthermore, when electric power is transmitted in a non-contact manner, the magnetic flux is formed around the convex portion 243 of the ferrite core 240 and a portion located outside thereof. The influence of the magnetic flux on the capacitor 220 disposed in the recess 244 is suppressed, and it is also effectively suppressed that the capacitor 220 does not operate properly due to induction heating. About the above operation | movement and an effect, the power transmission apparatus 400 is obtained similarly.

[Comparative example]
As shown in FIGS. 4 and 5, ferrite cores 240 and 440 having a flat plate shape are employed in power reception device 200 </ b> A and power transmission device 400 </ b> A in the comparative example. Capacitors 220 and 420 are arranged adjacent to coil units 230 and 430 in the horizontal direction. When this configuration is adopted, it is difficult to reduce the size of the entire apparatus in the horizontal direction as compared with the embodiment because of the presence of the capacitors 220 and 420. Further, when electric power is transmitted in a non-contact manner, the magnetic flux easily reaches the capacitors 220 and 420 disposed outside the ferrite cores 240 and 440, and a separate measure is required.

  Although the above embodiment has been described based on an example in which the power receiving device is mounted on an electric vehicle, the contents of the above embodiment may be applied to other than the electric vehicle. As mentioned above, although embodiment based on this invention was described, said disclosure content is an illustration and restrictive at no points. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 100 Electric vehicle, 110 Vehicle main body, 120 Vehicle ECU, 130 Rectifier, 140 Converter, 150 Battery, 160 Power control unit, 170 Motor unit, 180, 322 Communication unit, 200, 200A Power receiving device, 210 Power receiving unit, 220, 420 Capacitor 220T, 420T outer end face, 230, 430 coil unit, 240, 440 ferrite core, 241, 441 first main surface, 242, 442 second main surface, 243, 443 convex part, 244, 444 concave part, 250 power receiving coil, 300 External Power Supply Device, 310 High Frequency Power Device, 320 Power Transmission ECU, 330 AC Power Supply, 400, 400A Power Transmission Device, 410 Power Transmission Unit, 450 Power Transmission Coil, 1000 Power Transmission System, A1, A2 Dimensions, C1, C2 Dimensioned, D1, D2 coil height, H1, H2 projection height, T1, T2 depth.

Claims (1)

A power receiving device that receives power in a non-contact manner from the power transmitting device in a state of facing the power transmitting device,
A first main surface and a second main surface formed on the opposite side of the first main surface and positioned farther from the power transmission device than the first main surface when the power receiving device faces the power transmission device; A ferrite core in which a convex portion is formed on the first main surface, and a concave portion is formed at a position opposite to the convex portion on the second main surface;
A coil having a spiral shape and arranged so as to surround the convex portion on the first main surface;
A capacitor electrically connected to the coil,
The height of the convex portion from the first main surface substantially matches the coil height in the winding axis direction of the coil,
The capacitor is accommodated in the recess,
Power receiving device.

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