JP2012050209A - Non-contact power transmission system - Google Patents

Abstract

To provide a non-contact power transmission system capable of meeting the need for simultaneously transmitting power from a single power transmission device to a plurality of power receiving devices.
A non-contact power transmission system includes a power transmission device having a power transmission coil and a power reception device having a power reception coil and a magnetic flux collecting coil. The non-contact power transmission system 10 is a type that transmits power using electromagnetic induction, and transmits power to the power receiving coil 250 through a magnetic flux generated by passing a current through the power transmitting coil 150. The magnetic flux collecting coil 300 is for collecting magnetic flux generated in the power transmission coil 150 and efficiently delivering it to the power receiving coil 250 by resonating at a predetermined frequency.
[Selection] Figure 1

Description

  The present invention relates to a non-contact power transmission system that performs non-contact power transmission.

  There are three broadly known methods for transmitting power from a power transmitting device to a power receiving device in a contactless manner. One is a method of transmitting electric power from a coil on the power transmission side to a coil on the power reception side using electromagnetic induction through a magnetic flux (see, for example, Patent Document 1), and the other is a method for transmitting electric power. It is a method of converting (radiating) from wireless transmitting energy to transmitting antenna to receiving antenna in the form of electromagnetic waves. The other one is magnetic resonance (magnetic) by resonating power transmission device and power reception device. This is a method of transmitting power from a power transmission device to a power reception device using resonance (see, for example, Patent Document 2).

  As a technique for performing communication and power transmission using the same antenna, for example, there is one disclosed in Patent Document 3.

JP 2008-141940 A JP 2010-148174 A JP 2000-138621 A

  For example, there is a demand for arranging a plurality of portable devices on a single charging stand and charging the plurality of portable devices simultaneously. That is, there is a need to simultaneously transmit power from a single power transmission device to a plurality of power reception devices.

  However, current technology cannot meet such needs. Moreover, in the literature which discloses the technique which performs communication and electric power transmission with the same device like patent document 3, the main focus is on aiming at the improvement of communication characteristics, such as extension of a communication distance, and it mentioned above. There is no disclosure of power transmission technology that can serve as a reference to meet the needs.

  Therefore, an object of the present invention is to provide a non-contact power transmission system capable of meeting the above-described needs while disclosing a high efficiency technology specialized for power transmission.

The present invention is a first non-contact power transmission system,
A non-contact power transmission system for non-contact power transmission from a power transmission device having a power transmission coil to a power reception device having a power reception coil using electromagnetic induction,
Provided is a non-contact power transmission system further comprising a magnetic flux collecting coil for collecting magnetic flux generated in the power transmitting coil and efficiently transferring it to the power receiving coil.

Moreover, this invention is a 1st non-contact electric power transmission system as a 2nd non-contact electric power transmission system,
The magnetic flux collecting coil provides a non-contact power transmission system disposed between the power transmission coil and the power reception coil.

Moreover, this invention is a 1st non-contact electric power transmission system as a 3rd non-contact electric power transmission system,
The magnetic flux collecting coil provides a non-contact power transmission system disposed outside the power transmission coil and the power reception coil.

Moreover, this invention is a non-contact electric power transmission system in any one of 1st thru | or 3 as a 4th non-contact electric power transmission system,
The coupling coefficient between the power transmission coil and the flux collecting coil is 0.01 or more,
Provided is a non-contact power transmission system in which a coupling coefficient between the power receiving coil and the magnetic flux collecting coil is 0.3 or more.

Moreover, this invention is a 4th non-contact electric power transmission system as a 5th non-contact electric power transmission system,
Regarding the average outer dimension that is the average value of the distance from the center of gravity to the outer shape, the average outer dimension of the power receiving coil and the flux collecting coil is 1/5 or less of the average outer dimension of the power transmission coil,
Provided is a non-contact power transmission system in which an interval between the power receiving coil and the magnetic flux collecting coil is 1/10 or less of an average external dimension of the magnetic flux collecting coil.

Moreover, this invention is a non-contact electric power transmission system in any one of the 1st thru | or 5 as a 6th non-contact electric power transmission system,
A non-contact power transmission system further comprising a magnetic body disposed on a non-facing surface that is at least one surface of the power transmitting coil and the power receiving coil and is a surface opposite to the facing surface of the power transmitting coil and the power receiving coil. provide.

Moreover, this invention is a non-contact electric power transmission system in any one of 1st thru | or 6 as a 7th non-contact electric power transmission system,
Provided is a non-contact power transmission system further comprising a shield material disposed on the outermost surface on the non-facing surface of at least one of the power transmission coil and the power reception coil.

Further, the present invention is the first to seventh contactless power transmission system as the eighth contactless power transmission system,
The power transmission device generates the magnetic flux by flowing a current of a predetermined frequency to the power transmission coil,
The magnetic flux collecting coil provides a non-contact power transmission system that is adjusted so that the predetermined frequency is a resonance frequency.

Moreover, this invention is a non-contact electric power transmission system in any one of 1st thru | or 8 as a 9th non-contact electric power transmission system,
The power transmission device provides a contactless power transmission system including a plurality of power transmission coils.

Furthermore, the present invention is a non-contact power transmission method for non-contact power transmission from a power transmission device having a power transmission coil to a plurality of power reception devices each having a power reception coil using electromagnetic induction,
For each of the power receiving devices, by further providing a magnetic flux collecting coil for collecting the magnetic flux generated in the power transmitting coil and efficiently transferring it to the power receiving coil, A contactless power transmission method for transmitting power at the same time is provided.

  According to the present invention, since the magnetic flux generated by the power transmission coil is collected by the magnetic flux collecting coil and efficiently transferred to the power receiving coil, appropriate power transmission can be performed even when the power transmission coil is larger than the power receiving coil. it can. Therefore, for example, while providing one large power transmission coil on a charging stand, a plurality of portable devices can be charged simultaneously by placing a plurality of portable devices having a power receiving coil on the charging stand.

1 is a diagram schematically showing a contactless power transmission system according to an embodiment of the present invention. It is a figure which shows roughly the modification of the non-contact electric power transmission system of FIG. It is a figure which shows the transmission efficiency characteristic with respect to the position shift of the plane direction in the non-contact electric power transmission system of FIG. It is a figure which shows the transmission efficiency characteristic with respect to the gap of the perpendicular direction in the non-contact electric power transmission system of FIG.

  Referring to FIG. 1, a contactless power transmission system 10 according to an embodiment of the present invention includes a power transmission device 100 having a power transmission coil 150, and a power reception device 200 having a power reception coil 250 and a magnetic flux collecting coil 300. Electric power is transmitted to the power receiving coil 250 through a magnetic flux generated by passing a current through the power transmitting coil 150. That is, the non-contact power transmission system 10 according to the present embodiment transmits power from the power transmission device 100 to the power reception device 200 in a non-contact manner using electromagnetic induction. Here, the power receiving device 200 is, for example, a portable device such as a mobile phone, and the power transmitting device 100 is, for example, a charging base for these portable devices.

  The magnetic flux collecting coil 300 is for collecting magnetic flux generated in the power transmission coil 150 and efficiently delivering it to the power receiving coil 250 by resonating at a predetermined frequency. The magnetic flux collecting coil 300 according to the present embodiment is provided in the power receiving device 200. However, the present invention is not limited to this, and the power receiving device 200 and the magnetic flux collecting coil 300 may be separated.

  The power transmission coil 150, the power reception coil 250, and the magnetic flux collecting coil 300 may each be formed by winding with a single wire or a litz wire, or may be fabricated on a flat substrate such as an FPC or FR-4 substrate. Good.

  The magnetic flux collecting coil 300 according to the present embodiment is disposed between the power transmitting coil 150 and the power receiving coil 250 as shown in FIG. However, the present invention is not limited to this, as long as it is disposed close to the power receiving coil 250. For example, like the non-contact power transmission system 10a illustrated in FIG. 2, the magnetic flux collecting coil 300 may be disposed outside the power transmission coil 150 and the power reception coil 250 instead of between the power transmission coil 150 and the power reception coil 250. That is, as in the present embodiment, when both the power receiving coil 250 and the magnetic flux collecting coil 300 are provided in the power receiving device 200, the power receiving device 200 may be turned upside down and disposed on the power transmitting device 100. Good.

  As described above, the magnetic flux collecting coil 300 according to the present embodiment is adjusted so that the predetermined frequency is the resonance frequency. Here, the predetermined frequency is a frequency of a current flowing through the power transmission coil 150 in order to generate a magnetic flux. The resonance frequency of the flux collecting coil 300 is adjusted by adding a capacitor, or by using a capacitance component generated by the self-resonance of the flux collecting coil 300 itself or the overlap between the copper foil pattern on the substrate and the flux collecting coil 300. be able to.

  In the non-contact power transmission system 10 according to the present embodiment, the coupling coefficient between the power transmission coil 150 and the flux collecting coil 300 is 0.01 or more, and the coupling coefficient between the power receiving coil 250 and the flux collecting coil 300 is 0.3 or more. Thus, the power transmission coil 150, the power reception coil 250, and the magnetic flux collecting coil 300 are designed and arranged.

  In particular, in the non-contact power transmission system 10 according to the present embodiment, the average outer dimensions of the power receiving coil 250 and the magnetic flux collecting coil 300 are equal to or less than 1/5 of the average outer dimensions of the power transmitting coil 150, and The power transmission coil 150, the power reception coil 250, and the magnetic flux collecting coil 300 are designed and arranged so that the distance from the magnetic flux coil 300 is 1/10 or less of the average outer dimension of the magnetic flux collecting coil 300. Here, the average outer dimension is an average value of the distances from the center of gravity of each coil to the outer shape.

  A magnetic body may be arranged on at least one surface of the power transmission coil 150 and the power reception coil 250 and on a non-facing surface that is a surface opposite to the facing surfaces of the power transmission coil 150 and the power receiving coil 250. As the magnetic material, for example, a soft magnetic material such as amorphous alloy, permalloy, silicon steel, sendust alloy, and soft magnetic ferrite, which is a composite material combining one kind or a plurality of magnetic materials having different magnetic permeability. It can also be used.

  Moreover, it is good also as arrange | positioning a shielding material in the at least one non-facing surface of the power transmission coil 150 and the receiving coil 250. FIG. When the magnetic body mentioned above is arrange | positioned on the non-facing surface, it is good also as arrange | positioning a shielding material on the magnetic body. As the shield material, for example, a plate or sheet can be used.

  Although the power transmission device 100 illustrated in FIG. 1 includes only one power transmission coil 150, for example, a plurality of power transmission coils 150 may be juxtaposed in the power transmission device 100.

  In the non-contact power transmission system 10 according to the present embodiment, even if the power transmission coil 150 is considerably larger than the power receiving coil 250, the power collecting coil 300 is provided in the vicinity of the power receiving coil 250. 150 to the power receiving coil 250 can be performed with relatively high efficiency and stable power transmission. For this reason, it is also possible to arrange a plurality of power receiving devices 200 on one power transmitting device 100 and transmit power to these power receiving devices 200 simultaneously.

  In order to verify the capability of the non-contact power transmission system 10 according to the present embodiment, as an example, each of the power transmission coil 150, the power reception coil 250, and the magnetic flux collecting coil 300 in the non-contact power transmission system 10 is used by using a litz wire. Created. Specifically, the magnetic flux collecting coil 300 has an outer diameter of 40 mm, an inner diameter of 10 mm, a winding number of 20 turns per layer, two layers, and 40 turns. The power receiving coil 250 had an outer diameter of 30 mm, an inner diameter of 27 mm, and a winding number of 2 turns. The power transmission coil 150 had an outer diameter of 250 mm to 200 mm, an inner diameter of 180 mm to 228 mm, and a winding number of 10 turns. Furthermore, the magnetic flux collecting coil 300 and the power receiving coil 250 are arranged so that the coupling coefficient is 0.6.

  FIG. 3 shows an efficiency change with respect to the positional deviation of the power receiving coil 250 in the horizontal direction. The origin in FIG. 3 is a point where the center of the power transmission coil 150 and the center of the power reception coil 250 coincide. The vertical axis in FIG. 3 indicates the efficiency, and the horizontal axis indicates the positional deviation. As can be understood from FIG. 3, stable power transmission can be performed with a transmission efficiency of about 68% up to a position where the positional deviation is 100 mm.

  FIG. 4 shows the change in efficiency with respect to the gap in the vertical direction of the power receiving coil 250. The origin of FIG. 4 is a point where the center of the power transmission coil 150 and the center of the power reception coil 250 coincide. The vertical axis in FIG. 4 indicates the efficiency, and the horizontal axis indicates the gap. As understood from FIG. 4, stable power transmission can be performed with a transmission efficiency of about 67% up to a position where the gap is 50 mm.

  As mentioned above, although embodiment and Example of this invention were described using drawing, this invention is not limited to these examples, In the range which does not deviate from the summary of this invention, a member and a structure change are possible. Even if it exists, it is included in this invention. For example, the configuration of the non-contact power transmission system is not limited to that shown in FIG. 1, and various components such as omitting some of the components, adding other components, changing the connection relationship, and the like. Variations are possible. The resonance frequency of the coil can be set to an arbitrary frequency. That is, various modifications and corrections that can naturally be made by those skilled in the art are also included in the present invention.

  The non-contact power transmission system of the present invention can be used for, for example, a system that charges a mobile device such as a mobile phone, a headset, a digital camera, and a digital video by transmitting power from a charger / charging stand. it can.

DESCRIPTION OF SYMBOLS 10 Non-contact electric power transmission system 100 Power transmission apparatus 150 Power transmission coil 200 Power receiving apparatus 250 Power receiving coil 300 Magnetic flux collecting coil

Claims (10)

A non-contact power transmission system for non-contact power transmission from a power transmission device having a power transmission coil to a power reception device having a power reception coil using electromagnetic induction,
A non-contact power transmission system further comprising a magnetic flux collecting coil for collecting magnetic flux generated by the power transmitting coil and efficiently transferring the magnetic flux to the power receiving coil. The contactless power transmission system according to claim 1,
The said magnetic flux collecting coil is a non-contact electric power transmission system arrange | positioned between the said power transmission coil and the said power receiving coil. The contactless power transmission system according to claim 1,
The magnetic flux collecting coil is a non-contact power transmission system arranged outside the power transmission coil and the power reception coil. A contactless power transmission system according to any one of claims 1 to 3,
The coupling coefficient between the power transmission coil and the flux collecting coil is 0.01 or more,
A contactless power transmission system in which a coupling coefficient between the power receiving coil and the magnetic flux collecting coil is 0.3 or more. The contactless power transmission system according to claim 4,
Regarding the average outer dimension that is the average value of the distance from the center of gravity to the outer shape, the average outer dimension of the power receiving coil and the flux collecting coil is 1/5 or less of the average outer dimension of the power transmission coil,
The non-contact power transmission system, wherein an interval between the power receiving coil and the magnetic flux collecting coil is 1/10 or less of an average outer dimension of the magnetic flux collecting coil. A contactless power transmission system according to any one of claims 1 to 5,
The non-contact electric power transmission system further provided with the magnetic body arrange | positioned at the non-opposing surface which is an at least one surface of the said power transmission coil and the said receiving coil and is a surface on the opposite side of the opposing surface of the said power transmission coil and the said receiving coil. A contactless power transmission system according to any one of claims 1 to 6,
The non-contact electric power transmission system further provided with the shielding material arrange | positioned on the outermost surface on the said non-opposing surface of at least one of the said power transmission coil and the said power receiving coil. A contactless power transmission system according to any one of claims 1 to 7,
The power transmission device generates the magnetic flux by flowing a current of a predetermined frequency to the power transmission coil,
The non-contact power transmission system in which the magnetic flux collecting coil is adjusted so that the predetermined frequency is a resonance frequency. A contactless power transmission system according to any one of claims 1 to 8,
The power transmission device is a non-contact power transmission system including a plurality of the power transmission coils. A non-contact power transmission method for non-contact power transmission to a plurality of power receiving devices each having a power receiving coil from a power transmitting device having a power transmitting coil using electromagnetic induction,
For each of the power receiving devices, by further providing a magnetic flux collecting coil for collecting the magnetic flux generated in the power transmitting coil and efficiently transferring it to the power receiving coil, A non-contact power transmission method for transmitting power at the same time.

Images