JP2018121036A - Non-contact power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact power transmission device which does not degrade transmission/reception efficiency due to misalignment.SOLUTION: A non-contact power transmission device 10 includes a power transmission coil 2 and a power reception coil 3 that are arranged to face each other, and the power reception coil 3 is disposed within the area of the power transmission coil 2, and the length of the shorter side of the power transmission coil 2 and the length or the diameter of at least one of the sides of the power reception coil 3 substantially coincide. Therefore, it becomes unnecessary to precisely align the power reception coil 3 and the power transmission coil 2, and even if the position where the power reception coil 3 is disposed deviates in the longitudinal direction of the power transmission coil 2, the efficiency of transmission and reception does not decrease as long as the deviation is within the range of the area of the power transmission coil 2.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a contactless power transmission device.

  The conventional non-contact type power transmission device uses a power transmission coil and a power reception coil that perform power transmission and reception in a one-to-one manner, facing each other in a non-contact manner, and transmits electric power (or signals) by electromagnetic induction of the opposed coils. Technology (see Patent Document 1). In recent years, using such a technique, for example, a non-contact charger for charging a battery of a mobile phone or a smartphone in a non-contact manner has been put into practical use.

JP 2006-73059 A

  The contactless power transmission device of the present disclosure includes a power transmission coil and a power reception coil that are arranged to face each other, the power reception coil is disposed within the area of the power transmission coil, and the length of the side on the short side of the power transmission coil The length or diameter of at least one side of the sides of the power receiving coil is substantially the same.

(A)-(C) are each a top view which shows the non-contact-type electric power transmission apparatus which concerns on one Embodiment of this indication. It is a graph which shows the simulation result of each power transmission and reception efficiency of Drawing 1 (A)-(C). It is a top view which shows the non-contact-type electric power transmission apparatus which concerns on another embodiment of this indication. It is a graph which shows the simulation result of the efficiency of power transmission / reception of FIG.

  In the case of the electromagnetic induction system, the contactless power transmission device has the same shape of the power transmission and power reception coils, and the power transmission and reception efficiency is highest when there is no positional deviation in the vertical and horizontal directions when facing each other. When the power transmission and the power receiving coil are displaced, the power transmission / reception efficiency is significantly reduced.

  When performing a plurality of power transmissions / receptions, it is necessary to prepare the same number of power transmission and reception coils having substantially the same shape, and to generate and transmit a plurality of combinations in which the power transmission and reception coils face each other on a one-to-one basis. Therefore, one-to-multiple power transmission / reception that includes one power transmission coil and a plurality of power reception coils cannot be performed. Furthermore, in the non-contact power transmission device in which a power transmission coil and a power reception coil having a size 0.3 to 0.7 times that of the power transmission coil are opposed to each other as described in Patent Document 1, the size of the power reception coil Becomes smaller. Therefore, the wiring length of the coil is shortened, and power transmission / reception efficiency is lowered.

  On the other hand, in the contactless power transmission device of the present disclosure, the power receiving coil is disposed within the area of the power transmission coil, and the length of the side on the short side of the power transmission coil and at least one side of the power receiving coil side The length or diameter is approximately the same. Therefore, the difference in shape between the power transmission coil and the power reception coil can be minimized, and even when the position of the power reception coil is shifted in the longitudinal direction of the power transmission coil in one-to-one power transmission / reception. If it is within the range of the length of the side on the long side, there is an effect that the efficiency of power transmission and reception is not lowered. Also, even in one-to-multiple power transmission / reception, a plurality of power reception coils can be arranged for one power transmission coil as long as the length is within the length of the long side of the power transmission coil. Therefore, there is an effect that the efficiency of power transmission / reception due to the positional deviation does not decrease.

  A contactless power transmission device according to an embodiment of the present disclosure will be described with reference to FIG. A contactless power transmission device 10 shown in FIGS. 1A to 1C includes a power transmission coil 2 provided on a substrate 1a and a power reception coil 3 provided on a substrate 1b, and includes a power transmission coil 2 and a power reception coil 3. Is facing non-contact. The non-contact power transmission device 10 is a coil antenna for wireless power feeding (wireless power feeding), for example, Qi standard (125 kHz) for wireless power feeding (wireless power feeding), RF-ID (13. 56 MHz) can be applied.

  The power transmission coil 2 is provided in a spiral shape on the same layer of the substrate 1a, and is connected to a control circuit unit including a capacitor and a control IC by wiring. The power transmission coil 2 is made of a metal such as copper. The length of the short side of the power transmission coil 2 is substantially the same as the length or diameter of at least one side of the power receiving coil 3, and the long side of the power transmitting coil 2 is the length of the power receiving coil 3. It should be at least twice the length of the side. Such a shape of the power transmission coil 2 is preferably a horizontally long rectangle.

  The power receiving coil 3 is provided in a spiral shape on the same layer of the substrate 1b, and is connected to a control circuit substrate including a capacitor and a control IC by wiring. The power receiving coil 3 is made of a metal such as copper. The power receiving coil 3 is sized to be disposed within the area of the power transmission coil 2, and at least one of the sides has a length or diameter that is substantially the same as the length of the short side of the power transmission coil 2. This substantially coincidence means that the length of the side of the power receiving coil 3 is, for example, about 0.9 to 1.0 times the length of the short side of the power transmitting coil 2. The shape of the power receiving coil 3 is not particularly limited, but may be a rectangle, a square, a circle, or the like. In particular, even if the length of one side and the diameter is the same, the wire length of the coil wound by the square is longer than the circle. Therefore, it should be square.

  In the non-contact power transmission device 10, the power receiving coil 3 is arranged at a different location of the power transmitting coil 2 as shown in FIGS. The efficiency of power transmission / reception when the power receiving coil 3 is arranged at the positions shown in FIGS. 1A to 1C was simulated by a simulator (ANSYS HFSS). The result is shown in FIG. In FIG. 2, the graph of P1 shows the result of FIG. 1 (A), the graph of P2 shows the result of FIG. 1 (B), and the graph of P3 shows the result of FIG. 1 (C). At this time, the frequency for transmitting and receiving power is a frequency band of the Qi standard (125 kHz). When viewed in plan, the power transmission coil 2 is a horizontally long rectangle whose longitudinal side is at least twice as long as one side of the power reception coil 3 (the dimensions in the simulation are power transmission coil = 10 × 20 mm, power reception coil = 10 × 10 mm). The power receiving coil 3 is a square having one side that is the length of the short side of the power transmitting coil 2 when viewed in plan.

  From the graph of FIG. 2, the power receiving coil 3 has no particular difference in power transmission / reception efficiency even if it is arranged at any of the different locations P1 to P3 (left, center and right) of the power transmitting coil 2. I understand that. That is, the power receiving coil 3 is located within the range of the area of the power transmission coil 2 and is arranged at any position as long as the length of one side of the power receiving coil 3 matches the length of the short side of the power transmission coil 2. However, power can be transmitted and received with the same efficiency. This eliminates the need for exact alignment between the power receiving coil 3 and the power transmitting coil 2, and even if the position where the power receiving coil 3 is disposed is shifted in the longitudinal direction of the power transmitting coil 2, it is within the range of the area of the power transmitting coil 2. If so, the efficiency of power transmission and reception will not drop.

(Another embodiment)
FIG. 3 illustrates a contactless power transmission device 11 according to another embodiment of the present disclosure. In addition, about the member demonstrated with the above-mentioned non-contact-type electric power transmission apparatus 10, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  As shown in FIG. 3, the contactless power transmission device 11 is configured such that three power receiving coils 31, 32, and 33 are simultaneously opposed to positions P <b> 1 to P <b> 3 of the power transmitting coil 2. The length or diameter of at least one of the sides of the power receiving coils 31 to 33 is substantially the same as the length of the side on the short side of the power transmitting coil 2 as in the case of the power receiving coil 3 described above. The power receiving coils 31 to 33 are all disposed within the area of the power transmitting coil 2. The result of simulating the efficiency of power transmission and reception at this time is shown in FIG. The frequency for transmitting and receiving power is 125 kHz. In addition, the shape of the power receiving coils 31 to 33 is preferably a square or a circle as in the case of the power receiving coil 3.

  From the graph of FIG. 4, it can be seen that even when the plurality of power receiving coils 31 to 33 are simultaneously disposed in the power transmission coil 2, there is no particular difference in efficiency depending on the position where each power receiving coil is disposed. The reason why the peak of the graph is slightly lower than when the power receiving coil 3 is arranged alone (see FIG. 2) is that three power receiving coils 31 to 33 are simultaneously arranged with respect to the power transmitting coil 2. is there. It does not have a great influence on the efficiency of power transmission and reception.

  As described above, at least one side of the length of one side of the power receiving coil 3 (31 to 33) or the length of the short side of the horizontally long power transmitting coil 2 whose diameter is twice or more of the diameter and the side of the power receiving coil 3 By substantially matching the lengths or diameters of the power transmission coils 2 and minimizing the difference in shape between the power transmission coils 2 and the power reception coils 3, a plurality of power reception coils 3 can be arranged with respect to one power transmission coil 2 without being displaced. Therefore, power can be transmitted to and received from the plurality of power receiving coils 3 by one power transmitting coil 2.

  As described above, the contactless power transmission device according to the embodiment of the present invention has been described in detail. However, the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims. Improvements and changes are possible. For example, three or more power receiving coils may be disposed as long as they can be disposed within the area of the power transmitting coil. A magnetic sheet or the like may be attached to the power transmission coil or the power reception coil to suppress the generation of noise or improve power transmission / reception efficiency. Furthermore, it can also be used in the RF-ID frequency band (13.56 MHz).

DESCRIPTION OF SYMBOLS 1a, 1b board | substrate 2 Power transmission coil 3 Power receiving coil 31, 32, 33 Power receiving coil 10, 11 Non-contact-type power transmission device

Claims (3)

Including a power transmission coil and a power reception coil arranged opposite to each other;
A non-contact type wherein the power receiving coil is disposed within the area of the power transmitting coil, and the length of the short side of the power transmitting coil is substantially equal to the length or diameter of at least one side of the power receiving coil. Power transmission device.   The contactless power transmission device according to claim 1, wherein a shape of the power transmission coil is a rectangle.   The non-contact power transmission device according to claim 1, wherein a plurality of power receiving coils are arranged within an area of the power transmitting coil.

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