JP2011072176A - Non-contact power transmitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-contact power transmitter using a power transmission line, which can transmit power to the vicinity of a terminal at a high efficiency rate contact-freely from a power transmission line suitably, facilitating matching of power transmission lines despite a simple structure. <P>SOLUTION: The non-contact power transmitter 1A includes: an open type first line 31 which extends linearly and composes a power transmission line 3 for transmitting power from an ac power supply 2 to a terminal; and a power receiving object 4A having at least a second line 41A with an electromagnetic coupling part 41a which extends linearly. A gap is left when the electromagnetic coupling part 41a of the second line 41A of the power receiving object 4A is superposed and arranged with respect to the first line 31 so that it matches the first line 31 in their extending directions, and by their electromagnetic coupling, power of the AC power supply 2 is distributed and transmitted to the second line 41A from the first line 31. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a contactless power transmission device using spatial coupling of evanescent fields.

  Conventionally, research and development of contactless power transmission devices that transmit power in a contactless (wireless) manner has been actively conducted. Since the contactless power transmission device does not require mechanical contact, it has advantages such as high durability and low noise. Such contactless power transmission devices include those that use electromagnetic waves that propagate far away, and those that use spatial coupling of electromagnetic fields (evanescent fields) that do not propagate and exist only in the vicinity. . In the case of using electromagnetic waves, the energy on the power transmission side is radiated to the surroundings even if there is no power reception side unless special control is performed. As for what is performed using spatial coupling of the evanescent field, if there is a reception side, power (energy) of the transmission side is transmitted to the reception side according to the coupling with the reception side.

  Patent Document 1 describes a contactless power transmission device using electromagnetic induction by spatial coupling of an evanescent field. This is intended to be applied to pantographs, etc. There is a transmission line (cable) that transmits power from an AC power source toward the end, and a primary coil is provided at the tip, and on / off control of energization to the switch is performed. A large number of transmission-side units that can be connected to the required locations of the transmission line. A receiving-side power receiving body (moving body) having a secondary coil that is coupled to the primary coil by electromagnetic induction is arranged so that the primary coil and the secondary coil are arranged close to each other. Electricity is transmitted from the power transmission line to the power receiver even while moving along the line. Patent Document 2 discloses a method for transmitting power by using resonance due to spatial coupling of an evanescent field to cause resonance in resonators such as loop conductors provided on both the transmission side and the reception side. A contact power transmission device is described.

JP 2009-71909 A Special table 2009-501510

  However, in the device described in Patent Document 1, the transmission side unit provided at a required location of the transmission line is complicated, and a wasteful current flows or the transmission line becomes inconsistent due to the on / off control of a large number of units. Electric power is likely to be reflected, and it is not always easy to transmit power appropriately to the vicinity of the end of the transmission line. Patent Document 2 does not include a description of using a power transmission line, and even if it is applied to one using a power transmission line, it is considered that a problem similar to that of Patent Document 1 remains.

  The present invention has been made in view of the above reasons, and its purpose is to use a power transmission line, and it is easy to easily match the power transmission line to the vicinity of the end while having a simple structure. It is another object of the present invention to provide a contactless power transmission device that can transmit power at a high rate without contact from a power transmission line.

  In order to achieve the above object, the contactless power transmission device according to claim 1 constitutes a power transmission line that transmits power from an AC power source toward an end, and is an open-type first that extends linearly. And a power receiver having at least a second line having an electromagnetic coupling portion extending linearly, and the electromagnetic coupling portion of the second line of the power receiver has an extension direction with respect to the first line. When they are arranged so as to coincide with each other, there is a gap, and when they are electromagnetically coupled, the power of the AC power source is distributed from the first line to the second line and transmitted. To do.

  The contactless power transmission device according to claim 2 is the contactless power transmission device according to claim 1, wherein the power receiver is provided with a load on the AC power supply side of the electromagnetic coupling portion of the second line. The power transmitted to the second line is supplied to this load.

  The contactless power transmission device according to claim 3 is the contactless power transmission device according to claim 1, wherein the second line of the power receiver has a loop shape and extends linearly. And the power receiver further includes a third line having an electromagnetic coupling part extending in an extending direction of the second electromagnetic coupling part of the second line, and the third line. The electromagnetic coupling portion of the second line is overlapped with the second electromagnetic coupling portion of the second line in a state having a gap and is electromagnetically coupled, so that the power transmitted to the second line is transmitted from the second line to the third line. It is transmitted to the line of this.

  The contactless power transmission device according to claim 4 is the contactless power transmission device according to claim 3, wherein the power receiver is provided with a load on the AC power supply side of the electromagnetic coupling portion of the third line. The power transmitted to the third line is supplied to this load.

  The contactless power transmission device according to claim 5 is the contactless power transmission device according to claim 3 or 4, wherein the power receiver is provided on a terminal side of the power transmission line, and other power receivers on a front side thereof. Is provided.

  The contactless power transmission device according to claim 6 is the contactless power transmission device according to any one of claims 1 to 5, wherein at least the electromagnetic coupling portion of the second line and the first line are in a thin plate shape. However, it is characterized in that they are arranged on the broad side.

  The contactless power transmission device according to claim 7 is the contactless power transmission device according to claim 6, wherein the second line is formed by shifting the electromagnetic coupling portion in the width direction from the first line. It is characterized in that the electric power transmitted is made small while keeping the gap with one line constant.

  The contactless power transmission device according to claim 8 is the contactless power transmission device according to any one of claims 1 to 7, wherein the power transmission line is fixed to a passage or a road, and the power receiver moves while moving. It is characterized by receiving power from the track.

  The contactless power transmission device according to claim 9 is the contactless power transmission device according to any one of claims 1 to 8, wherein the electromagnetic coupling portion of the second line has an inductive component and / or a capacitive component. A protruding portion protruding in the width direction is provided so as to be added.

  The contactless power transmission device according to claim 10 is the contactless power transmission device according to claim 9, wherein the protruding portion is connected to a ground conductor so that an inductive component is added. It is characterized by.

  The contactless power transmission device according to an eleventh aspect is the contactless power transmission device according to the tenth aspect, wherein one protrusion is provided near the center.

  The contactless power transmission device according to claim 12 is the contactless power transmission device according to any one of claims 1 to 11, wherein at least the electromagnetic coupling portion of the second line is made of a metamaterial. And

  According to the contactless power transmission device of the present invention, there is a gap when the electromagnetic coupling portion of the second line of the power receiver is arranged so as to coincide with a part of the first line so as to coincide with the extending direction. Because they are electromagnetically coupled, the power of the AC power supply is distributed and transmitted from the first line to the second line, so that the transmission line can be matched while having a very simple structure. It becomes easy to obtain, and power can be transmitted at a high rate without contact from the power transmission line appropriately up to the vicinity of the end.

It is a schematic diagram which shows the structure of 1 A of non-contact electric power transmission apparatuses which concern on embodiment of this invention. The structure of the principal part of 1 A of non-contact electric power transmission apparatuses same as the above is shown, Comprising: (a) is a top view, (b) is a side view. It is a characteristic view of electric power transmission of contactless power transmission device 1A same as the above. It is a schematic diagram which shows the structure which applied the non-contact electric power transmission apparatus 1A same as the above. It is a schematic diagram which shows the structure of the non-contact electric power transmission apparatus 1B which concerns on another embodiment of this invention. The structure of the principal part of the non-contact electric power transmission apparatus 1B same as the above is shown, Comprising: (a) is a top view, (b) is a side view. It is a characteristic view of electric power transmission of the non-contact electric power transmission apparatus 1B same as the above. It is a schematic diagram which shows the structure which applied the non-contact electric power transmission apparatus 1B same as the above. 1A is a plan view and FIG. 2B is a side view of a contactless power transmission device 1C obtained by modifying the structure of a power receiver 4A of the contactless power transmission device 1A according to the embodiment of the present invention. FIG. 2 is a view similar to FIG. 2, wherein (a) is a plan view and (b) is a side view. (A) is a characteristic diagram of electric power transmission about the structure of FIG. 9, (b) is the structure of FIG. FIG. 10 is another characteristic diagram of power transmission for the structure of FIG. 9. (A) is a top view and (b) is a side view of non-contact electric power transmission apparatus 1D which deform | transformed the structure of the power receiving body 4B of the non-contact electric power transmission apparatus 1B which concerns on embodiment of this invention. 6A and 6B have the same structure as that of FIG. 6, in which FIG. 6A is a plan view and FIG. 6B is a side view. FIG. 15A is a characteristic diagram of power transmission for the structure of FIG. 13, and FIG. 14B is a characteristic diagram of power transmission for the structure of FIG. 14. The contactless power transmission device 1E obtained by modifying the structure of the power receiver 4A of the contactless power transmission device 1A is a plan view, and (b) is a side view. The contactless power transmission device 1F obtained by modifying the structure of the power receiver 4A of the contactless power transmission device 1C is a plan view, and (b) is a side view. FIG. 18 is a characteristic diagram of power transmission for the structure of FIG. 17.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. As shown in the schematic diagram of FIG. 1, the contactless power transmission device 1 </ b> A according to the embodiment of the present invention constitutes a power transmission line 3 that transmits power from the AC power source 2 toward the end, and is linear (unevenness). Power is taken out from the middle of the first line 31 extending uniformly) to the power receiving body 4A without contact, and is supplied to a load 40 such as a power supply circuit or a charging circuit included in the power receiving body 4A. . At the end (termination) of the two lines of the power transmission line 3 (the power line (power signal line) and the ground line, which is part of the first line 31), a termination resistor 3a is added between them.

  The first line 31 of the contactless power transmission device 1A is an open-type line, and an evanescent field due to electric power (power signal) passing through the first line 31 is open in at least one direction and is not blocked by the other. More specifically, as shown in the structural diagram of FIG. 2, the first line 31 is a thin plate (flat) conductor having broad sides (wide surfaces) as upper and lower surfaces. The width Sa of the broad side is uniform. As for the 1st track | line 31, the evanescent field is open | released at least upwards. Although omitted in FIG. 2, a ground line is provided below or on the side of the first line 31 in parallel with the first line 31. Moreover, the 1st track | line 31 is extended long, The both ends are the input end T1 and the output end T2. The power from the AC power source 2 is input to the input terminal T1. The first line 31 is made of one material and has a uniform thickness (narrow side width). The same applies to the second lines 41A and 41B and the third line 42 described later.

  The power receiver 4A includes a second line 41A having an electromagnetic coupling portion 41a extending linearly. The electromagnetic coupling portion 41a of the second line 41A has a required gap Se when arranged in parallel with the first line 31 so as to coincide with the extending direction, and these are electromagnetically coupled by the evanescent field. Will do. More specifically, as shown in FIG. 2, the electromagnetic coupling portion 41 a of the second line 41 </ b> A has broad sides on the upper side and the lower side, and the lower side is the upper side of the first line 31. There is a gap Se between the two surfaces. When the electromagnetic coupling portion 41a of the second line 41A and the first line 31 are arranged so as to overlap on the broad side, they are strongly electromagnetically coupled. Both ends of the second line 41A are an output end T3 and an output end T4. The load 40 is connected to the output end T4, that is, the input end T1 side (that is, the AC power supply 2 side) of the electromagnetic coupling portion 41a of the second line 41A. In FIG. 2, the ground conductor is omitted.

The simulation about the non-contact electric power transmission apparatus 1A is shown. The width Sa of the first line 31 in FIG. 2 is uniformly set to 1.7 mm, and the length Sb and the width Sc of the electromagnetic coupling portion 41a of the second line 41A are set to 16.7 mm and 0.6 mm, respectively. The width Sd of the second line 41A other than the coupling portion 41a is 1.7 mm. The clearance Se between the electromagnetic coupling portion 41a of the second line 41A and the first line 31 was 0.2 mm. Each line was formed in an insulating material having a relative dielectric constant of 3.37. If it carries out like this, the support of a track will become firm. 3 shows that when the frequency of the power signal input to the input terminal T1 is changed, the ratio S _{11 of} the power reflected to the input terminal T1, the ratio S _{21 of} the power output to the output terminal T2, and the output terminal T3 to the output terminal T3. The ratio S ₃₁ of output power and the ratio S ₄₁ of power output to the output terminal T4 are shown.

As shown the curve of the power ratio S ₄₁ that is output to the output terminal T4 is 3, is input to the input terminal T1 power is distributed in a large proportion to the output terminal T4. The maximum value is about −3 dB (about 50%), and the maximum value is obtained when the frequency of the power signal input to the input terminal T1 is in the vicinity of 2.5 GHz. This is because the length Sb of the electromagnetic coupling portion 41a of the second line 41A is 16.7 mm, which substantially matches the ¼ wavelength when the frequency of the power signal is near 2.5 GHz. is there. The electric power transmitted to the respective parts constituting the electromagnetic coupling portion 41a of the second line 41A by electromagnetic coupling with the first line 31 is synthesized, and most of the electric power proceeds to the output terminal T4. This is the same as the principle of the directional coupler. Ratio S ₄₁ of power outputted to the output terminal T4 decreases as becomes smaller or larger from the frequency at which the maximum value is obtained.

As the curve of the ratio _{S 11} of the power reflected to the input terminal T1 in FIG. 3, power reflected to the input terminal T1 is, -12 dB around the frequency of about 2.5GHz and less. Further, as shown by the curve of the power ratio _{S 31} that is output to the output terminal T3, the power output to the output terminal T3 are very small and about 2.5GHz at -20dB about frequency.

As described above, the power input to the input terminal T1 (the power of the AC power supply 2) is distributed and transmitted from the first line 31 to the second line 41A and supplied to the load 40 via the output terminal T4. The Then, by a quarter or near the wavelength of the second line 41A electromagnetic coupling portions 41a power signal length Sb of the maximum value near the ratio S ₄₁ of power outputted to the output terminal T4 Can be. Further, the electromagnetic coupling portion 41a of the second line 41A is shifted in the width Sa direction away from the first line 3 to reduce the electromagnetic coupling, to reduce the ratio S ₄₁ of power outputted to the output terminal T4 Accordingly, the power transmitted to the second line 41A and supplied to the load 40 can be adjusted to be small.

  On the other hand, since the power reflected by the input terminal T1 is small, that is, the first line 31 (and the power transmission line 3 constituted thereby) is matched, there is no power from the first line 31 until it reaches the end. Electric power can be transmitted to the power receiver 4A at a high rate by contact.

  Moreover, since electric power is transmitted by electromagnetic coupling between the first line 31 and the electromagnetic coupling portion 41a of the second line 41A of the power receiver 4A, there is no coil and the structure is very simple. For this reason, the contactless power transmission device 1A has few failures and high durability.

Next, a case where the power receiver 4A moves along the power transmission line 3 will be described. Since the width Sa of the first line 31 is uniform, the power output to the output terminal T4 is superimposed at any position on the first line 31 where the electromagnetic coupling portion 41a of the second line 41A is superimposed. ratio _{S 11} power reflected in the ratio _{S 41} and input end T1 of unchanged. That is, even when the power receiver 4 </ b> A moves, power can be distributed to the power receiver 41 at a high ratio, and the power reflected on the power transmission line 3 can be reduced.

  If the power transmission line 3 is fixed to the passage of the power receiving body 4A in a clean room or a place that adversely affects the human body in a factory that dislikes dust, the power receiving body 4A can be contacted with electric power from the power transmission line 3 while moving. Will always be operational. When charging a vehicle such as an electric vehicle, the power transmission line 3 is fixed to a road (lane or the like), and the vehicle (power receiving body 4A) moves along the power transmission line 3 to stop the vehicle. It is also possible to make it possible to charge without any problems.

As shown in FIG. 4, for example, the contactless power transmission device 1 </ b> A can be provided with a plurality of power receivers 4 </ b> A along the power transmission line 3. If each of the power receivers 4A ₁ , 4A ₂ , 4A _{3 in} FIG. 4 can extract -3 dB of power, the power receiver 4A ₁ close to the AC power source 2 of the transmission line 3 has ₁ of the power output from the AC power source 2. / 2 is transmitted. The next power receiving body 4A ₂ transmits about ½ of the remaining power extracted by power receiving body 4A ₁ (that is, about ¼ of the power output from AC power supply 2). The next power receiving body 4A ₃ transmits about 1/2 of the remaining power extracted by the power receiving bodies 4A ₁ and 4A ₂ (that is, about 1/8 of the power output from the AC power supply 2). The remaining power transmitted to the power receivers 4A ₁ , 4A ₂ , 4A ₃ is consumed by the termination resistor 3a. The electromagnetic coupling portion 41a of the second line 41A is shifted from the first line 31 in the width Sa direction so as to weaken the electromagnetic coupling so that the power taken out by one power receiving body 4A (for example, the power receiving body 4A ₁ ) does not become too large. It is also possible. Needless to say, the number of the power receiving bodies 4A is not limited to three but may be two or four or more. In addition, the terminal resistor 3a can be replaced with a rectifier circuit, a charging circuit, or the like having an equivalent impedance to effectively use the power consumed by the terminal resistor 3a.

  Next, a contactless power transmission device 1B according to another embodiment of the present invention will be described. The contactless power transmission device 1B is different from the contactless power transmission device 1A in the power receiving body. As shown in the schematic diagram of FIG. 5, the power receiver 4B of the contactless power transmission device 1B includes a second line 41B having an electromagnetic coupling portion 41a similar to the above, forming a substantially square loop shape, and A second electromagnetic coupling portion 41b extending linearly is provided at a position facing the electromagnetic coupling portion 41a. The power receiver 4B further includes a third line 42 having an electromagnetic coupling portion 42a extending in the extending direction of the second electromagnetic coupling portion 41b of the second line 41B. The electromagnetic coupling portion 42a of the third line 42 is disposed in parallel with the second electromagnetic coupling portion 41b of the second line 41B with a necessary gap therebetween, and is electromagnetically coupled by the evanescent field.

  More specifically, as shown in the structural diagram of FIG. 6, the upper and lower surfaces of the second electromagnetic coupling portion 41b of the second line 41B and the electromagnetic coupling portion 42a of the third line 42 are broadside, respectively. They are arranged so as to overlap each other on the broad side and are strongly electromagnetically coupled. Both ends of the third line 42 are an output end T3 and an output end T4. The load 40 is connected to the output end T4, that is, the input end T1 side (that is, the AC power supply 2 side) of the electromagnetic coupling portion 42a of the third line 42. In FIG. 6, the ground conductor is omitted.

The simulation about the non-contact electric power transmission apparatus 1B is shown. The width Sa of the first line 31 in FIG. 6 is uniformly 1.8 mm, the length Sb of the electromagnetic coupling portion 41a of the second line 41B, the second electromagnetic coupling portion 41b of the second line 41B, and The length Sf of the electromagnetic coupling portion 42a of the third line 42 is 16.7 mm, the width Sc of the electromagnetic coupling portion 41a of the second line 41B is 0.7 mm, and the second length of the second line 41B is 2nd. The width Sg of the electromagnetic coupling portion 41b and the electromagnetic coupling portion 42a of the third line 42 is 0.6 mm, and the width Sd of the second line 41B other than the electromagnetic coupling portion 41a and the second electromagnetic coupling portion 41b is 1. The width Sh of the third line 42 other than the electromagnetic coupling portion 42a was 1.8 mm. A gap Se between the electromagnetic coupling portion 41a of the second line 41B and the first line 31, and a gap Si between the second electromagnetic coupling portion 41b of the second line 41B and the electromagnetic coupling portion 42a of the third line 42. Both were set to 0.2 mm. The entire length of the second line 41B (loop length) was 66.8 mm. Each line was formed in an insulating material having a relative dielectric constant of 3.37. FIG. 7 shows that when the frequency of the power signal input to the input terminal T1 is changed, the ratio S _{11 of} the power reflected to the input terminal T1, the ratio S _{21 of} the power output to the output terminal T2, and the output terminal T3 The ratio S ₃₁ of output power and the ratio S ₄₁ of power output to the output terminal T4 are shown.

As the curve of the power ratio S ₄₁ that is output to an output terminal T4 in FIG. 7, the power that is input to the input terminal T1 is very distributed large proportion to the output terminal T4. The maximum value is about 0 dB, and the maximum value is obtained when the frequency of the power signal input to the input terminal T1 is around 2.5 GHz. As described above, since the length Sb of the electromagnetic coupling portion 41a of the second line 41B is 16.7 mm, when the frequency of the power signal is near 2.5 GHz, the power transmitted to the second line 41B is It proceeds to the input end T1 side of the electromagnetic coupling portion 41a. Since the entire length of the second line 41B is 66.8 mm and substantially coincides with one wavelength of the power signal, the power transmitted to the second line 41B resonates and is amplified. And the electric power is transmitted to the 3rd track | line 42 by the electromagnetic coupling of the 2nd electromagnetic coupling part 41b of the 2nd track | line 41B, and the electromagnetic coupling part 42a of the 3rd track | line 42, and most progresses to the output terminal T4. To be. Ratio S ₄₁ of power outputted to the output terminal T4 decreases as becomes smaller or larger from the frequency at which the maximum value is obtained.

As the curve of the power ratio _{S 11} to be reflected to the input terminal T1 in FIG. 7, power reflected to the input terminal T1 is, -15 dB around the frequency of about 2.5GHz and less. Further, as shown by the curve of the power ratio _{S 31} that is output to the output terminal T3, the power output to the output terminal T3 are very small as about -26dB at a frequency of about 2.5 GHz.

As described above, the power input to the input terminal T1 (the power of the AC power supply 2) is distributed and transmitted from the first line 31 to the second line 41B, and further from the second line 41B to the third line. It is transmitted to the line 42 and supplied to the load 40 via the output terminal T4. At that time, the length Sb of the electromagnetic coupling portion 41a of the second line 41B and the length Sf of the second electromagnetic coupling portion 41b of the second line 41B and the electromagnetic coupling portion 42a of the third line 42 are obtained. Both are set to ¼ of the wavelength of the power signal or the vicinity thereof, and the total length of the second line 41B is set to one wavelength of the power signal or in the vicinity thereof, whereby the ratio S _{41 of the} power output to the output terminal T4. Can be close to the maximum value. The contactless power transmission device 1B has a slightly more complicated structure than the contactless power transmission device 1A, but the ratio of the power that can be transmitted from the power transmission line 3 to the power receiver 4B can be increased. It is the same as the contactless power transmission device 1A that the first line 31 can be easily matched and can be applied to the moving power receiver 4B.

  The non-contact power transmission apparatus 1B can be provided with a plurality of power receiving bodies 4B in the same manner as described with reference to FIG. 4 for the non-contact power transmission apparatus 1A. In this case, since the power that can be extracted by one power receiving body 4B is larger than the power receiving body 4A in the contactless power transmission device 1A, the power extracted by one power receiving body 4B is adjusted so as not to be too large.

Moreover, as shown in FIG. 8, it is also possible to provide the power receiving body 4B on the terminal side of the power transmission line 3, and to provide the plurality of power receiving bodies 4A ₁ , 4A ₂ , 4A ₃ on the front side. In this way, almost all of the remaining power extracted by the power receivers 4A ₁ , 4A ₂ , 4A ₃ can be extracted from the power transmission line 3 by the power receiver 4B. It becomes possible to reduce.

  Next, the structure of the power receiving body 4A (or 4B) was modified to provide a protruding portion protruding in the width direction (perpendicular to the extending direction) in the electromagnetic coupling portion 41a of the second line 41A (or 41B). Explain things.

  FIG. 9 shows a modification of the power receiving body 4A of the contactless power transmission device 1A, in which a projecting portion 41aa projecting in the width direction is provided in the electromagnetic coupling portion 41a of the second line 41A, and the tip end portion is formed in the ground conductor 49 through hole. 1C shows a contactless power transmission device 1C to which an inductive component is added by connecting via a conductor in 49a. For comparison, FIG. 10 shows a non-contact power transmission apparatus 1A having the same structure as that of FIG. 2, that is, a structure having no protrusion 41aa and through-hole 49a.

FIG. 11A shows the structure shown in FIG. 9 and FIG. 11B shows the ratio shown in FIG. 10 when the frequency of the power signal input to the input terminal T1 is changed. This is a result of the simulation of S ₁₁ , the ratio S _{21 of} power output to the output terminal T 2, the ratio S _{31 of} power output to the output terminal T 3, and the ratio S ₄₁ of power output to the output terminal T 4. In these simulations, the gap Se between the electromagnetic coupling portion 41a of the second line 41A and the first line 31 is increased to 0.5 mm, and the electromagnetic coupling of the second line 41A is made closer to the actual case. It is assumed that there is air (that is, a relative dielectric constant of 1.0) in the gap Se between the portion 41a and the first line 31, and an insulating material having a relative dielectric constant of 3.38 is present between the other lines.

  In the simulation of FIG. 11A, the width Sa of the first line 31 and the width Sc of the electromagnetic coupling portion 41a of the second line 41A are both 2.0 mm, and the second line 41A other than the electromagnetic coupling portion 41a is used. The width Sd was 2.0 mm. The length Sb of the electromagnetic coupling portion 41a of the second line 41A was 25.5 mm. The protrusion 41aa is provided in the center of the electromagnetic coupling portion 41a of the second line 41A, the protrusion length Sj is 1.5 mm, the through hole 49a is 1 mm in diameter, and the length is 1.4 mm. In the simulation of FIG. 11B, the width Sa of the first line 31, the width Sc of the electromagnetic coupling part 41a of the second line 41A, and the width Sd of the second line 41A other than the electromagnetic coupling part 41a are all 2. It was 4 mm. Although these dimensions are slightly different from those in FIG. 11A, it has been confirmed that the influence is small. The length Sb of the electromagnetic coupling portion 41a of the second line 41A is 17.0 mm.

Figure 11 simulation result of (b) is the ratio _{S 41} of power outputted to the output terminal T4, and -6dB of the maximum value when the frequency of the input power signal to the input terminal T1 of 2.5GHz vicinity it is, the ratio _{S 11} of the power reflected to the input end T1 of this time is of the order of -17 dB. Also, the ratio S ₁₁ of the power reflected to the input end T1, and increases as the frequency increases. This point is significantly different from the simulation result shown in FIG. 3 described above, and the cause is that in the simulation of FIG. 11B, the electromagnetic coupling portion 41a of the second line 41A and the first line 31 This is because there is air in the gap Se, and the insulating material around the first line 31 is inhomogeneous, thereby causing the first line 31 to be mismatched.

On the other hand, in FIG. 11A, the ratio S ₄₁ of the power output to the output terminal T4 is about −3.5 dB when the frequency of the power signal input to the input terminal T1 is near 2.5 GHz. The ratio S ₁₁ of the power reflected at the input terminal T1 at that time is about −17.5 dB. The ratio S ₁₁ of the power reflected to the input terminal T1, the frequency is stabilized at 2.5GHz vicinity, not increase even when the frequency becomes larger than that. This is because the mismatch of the first line 31 is canceled by the inductive component of the electromagnetic coupling portion 41a of the second line 41A.

Thus, even if the gap Se between the electromagnetic coupling portion 41a of the second line 41A and the first line 31 is increased by adding an inductive component to the electromagnetic coupling portion 41a of the second line 41A, the output terminal the ratio S ₄₁ of power delivered to T4 on which can be sufficiently secured, it is possible to reduce the ratio S ₁₁ of the power reflected to the input terminal T1.

FIG. 12 shows a simulation result obtained by setting the frequency of the power signal to 2.45 GHz, providing two protruding portions 41aa, and symmetrically separating from the center of the electromagnetic coupling portion 41a of the second line 41A. From this result, the two projecting portions 41aa, 41aa, when provided in contact with the central, largest ratio S ₄₁ of power outputted to the output terminal T4, the ratio S ₁₁ of the power reflected smallest . Therefore, it is preferable to provide one protruding portion 41aa near the center.

  FIG. 13 shows a modification of the power receiving body 4B of the contactless power transmission device 1B, in which a projecting portion 41aa projecting in the width direction is provided in the electromagnetic coupling portion 41a of the second line 41B, and the tip end portion is formed in the ground conductor 49 as a through hole. A contactless power transmission device 1D to which an inductive component is added by connecting through a conductor in 49a is shown. For comparison, FIG. 14 shows a non-contact power transmission apparatus 1B having the same structure as that of FIG. 6, that is, a structure having no protrusion 41aa and through-hole 49a.

FIG. 15A shows the structure of FIG. 13 and FIG. 15B shows the structure of FIG. 14. The ratio of the power reflected to the input terminal T1 when the frequency of the power signal input to the input terminal T1 is changed. This is a result of the simulation of S ₁₁ , the ratio S _{21 of} power output to the output terminal T 2, the ratio S _{31 of} power output to the output terminal T 3, and the ratio S ₄₁ of power output to the output terminal T 4. In these simulations, the gap Se between the electromagnetic coupling portion 41a of the second line 41B and the first line 31 is increased to 0.5 mm, and the electromagnetic coupling portion 41a of the second line 41B and the first line 31 are separated. It is assumed that there is air (that is, a relative dielectric constant of 1.0) in the gap Se, and an insulating material having a relative dielectric constant of 3.38 is present between the other lines.

  In the simulation of FIG. 15A, the width Sa of the first line 31 and the width Sc of the electromagnetic coupling portion 41a of the second line 41B are both 2.4 mm, and the second line 41B other than the electromagnetic coupling portion 41a is used. The width Sd was 2.4 mm. The length Sb of the electromagnetic coupling portion 41a of the second line 41A was 20.0 mm. The protruding portion 41aa is provided at the center of the electromagnetic coupling portion 41a of the second line 41A, the protruding length Sj is 1.5 mm, the through hole 49a is 1 mm in diameter, and the length is 1.5 mm. In the simulation of FIG. 15B, the width Sa of the first line 31, the width Sc of the electromagnetic coupling portion 41a of the second line 41A, and the width Sd of the second line 41A other than the electromagnetic coupling portion 41a are all 2. It was 4 mm. The length Sb of the electromagnetic coupling portion 41a of the second line 41A was 18.6 mm.

Figure 15 simulation result of (b) is the ratio _{S 41} of power outputted to the output terminal T4, the frequency of the input power signal to the input terminal T1 becomes -2.5dB about when 2.5GHz vicinity The ratio S ₁₁ of the power reflected at the input terminal T1 at that time is about −8 dB. Such increase in power ratio S ₁₁ to be reflected to the input terminal T1 is electromagnetically coupled portion 41a of the second line 41B is in the gap Se of the first line 31 a first line if there is air This is because the insulating material around 31 is inhomogeneous, and the first line 31 is thereby mismatched.

On the other hand, in FIG. 15A, the ratio S ₄₁ of the power output to the output terminal T4 is about −0 dB when the frequency of the power signal input to the input terminal T1 is near 2.5 GHz. and has a ratio _{S 11} at the time power reflected to the input terminal T1 is smaller about -17 dB. This is because the mismatch of the first line 31 is canceled by the inductive component of the electromagnetic coupling portion 41a of the second line 41B. Thus, even if the gap Se between the electromagnetic coupling portion 41a of the second line 41B and the first line 31 is increased by adding an inductive component to the electromagnetic coupling portion 41a of the second line 41B, the output terminal the ratio S ₄₁ of power delivered to T4 on which can be sufficiently secured, it is possible to reduce the ratio S ₁₁ of the power reflected to the input terminal T1.

  In this manner, excellent characteristics can be obtained by adding an inductive component to the electromagnetic coupling portion 41a of the second line 41A (or 41B) of the power receiver 4A (or 4B). In addition to this, an example in which a protruding portion protruding in the width direction is provided on the electromagnetic coupling portion 41a of the second line 41A (or 41B) is one that adds a capacitance component. For example, like the contactless power transmission device 1E shown in FIG. 16 in which the power receiver 4A of the contactless power transmission device 1A is modified, the electromagnetic coupling portion 41a is provided with a protrusion 41ab having a relatively large area protruding in the width direction. A capacitance component between the first line 31 and the first line 31 can be added.

It is also possible to add both inductive components and capacitive components. FIG. 17 shows a modification of the contactless power transmission device 1C described above, in which projecting portions 41ab ′ and 41ab ′ projecting in the width direction are provided at both ends of the electromagnetic coupling portion 41a of the second line 41A. 3 shows a contactless power transmission device 1F with a capacitance component between 31 and 31. FIG. 18 shows a ratio S _{11 of} power reflected to the input terminal T 1 and a ratio S _{21 of} power output to the output terminal T 2 when the frequency of the power signal input to the input terminal T 1 is changed. ratio S ₃₁ of power outputted to the output terminal _T3, the results of a simulation of the power ratio S ₄₁ that is output to the output terminal T4. The width Sa of the first line 31, the length Sb of the electromagnetic coupling part 41a of the second line 41A, the width Sc of the electromagnetic coupling part 41a of the second line 41A, the electromagnetic coupling part 41a of the second line 41A and the first The gap Se of one line 31, the protruding length Sj, and the diameter and length of the through hole 49a are the same as those in the simulation of FIG. Although the width Sd of the second line 41A other than the electromagnetic coupling portion 41a is narrowed, the influence is small.

In FIG. 18, the ratio S ₄₁ of the power output to the output terminal T4 is about −2.5 dB when the frequency of the power signal input to the input terminal T1 is around 2.5 GHz. ratio _{S 11} of the power reflected to the input terminal T1 is of the order of -25 dB. Thus, the ratio S ₄₁ of power outputted to the output terminal T4, the power ratio S ₁₁ to be reflected to the input terminal T1 is improved.

  The contactless power transmission apparatus according to the embodiment of the present invention has been described above. However, the present invention is not limited to that described in the above-described embodiment, and is within the scope of the matters described in the claims. Various design changes are possible. For example, between the electromagnetic coupling portion 41a of the first line 31 and the second line 41A (or 41B) or between the second electromagnetic coupling portion 41b of the second line 41B and the electromagnetic coupling portion 42a of the third line 42. Broadside overlap is not limited to the vertical direction (vertical direction), but can also be in the horizontal direction depending on the location where the first line 31 is disposed. In addition, it is very preferable that each line is a thin plate and the electromagnetic coupling between the lines is performed on the broad side, but at least a part of the electromagnetic coupling can also be performed on the narrow side (narrow surface). It is. Depending on the case, it is also possible to use a rod-like (circular or elliptical cross section) line.

In addition, for the AC power supply 2 and the load 40 to be applied, an alternating current with a low frequency (for example, about 10 MHz or less) is easier to process and has a lower manufacturing cost. In the case of such a frequency, the electromagnetic coupling portion 41a of the second line 41A (or 41B) is very long (for example, about 10 m) and is difficult to handle. Therefore, a metamaterial (for example, a right-hand / left-handed composite line (for example, a right-hand / left-handed composite line)) is formed on the electromagnetic coupling portion 41a of the second line 41A (or 41B). CRLH line)) can be used. In this case, increase it is possible to shorten the length of the electromagnetic coupling portion 41a of the second line 41A (or 41B), the maximum value of the power ratio S ₄₁ that is output to the output terminal T4 of about 0dB It is also possible to make it.

1A, 1B Non-contact power transmission device 2 AC power source 3 Transmission line 31 First line 4A, 4B Power receiver 40 Load 41A, 41B Second line 41a Electromagnetic coupling portion 41b of second line 41b Second of second line 42 The third line 42a The electromagnetic coupling part of the third line Se The gap between the electromagnetic coupling part of the first line and the second line

Claims (12)

An open-type first line that constitutes a power transmission line that transmits power from the AC power source toward the end, and extends linearly;
A power receiving body including at least a second line having an electromagnetic coupling portion extending linearly; and
When the electromagnetic coupling portion of the second line of the power receiver is arranged so as to overlap the extending direction of the first line, there is a gap, and they are electromagnetically coupled, thereby A contactless power transmission device, wherein power is distributed from a first line to a second line and transmitted. The contactless power transmission device according to claim 1,
The power receiving body is provided with a load on the AC power supply side of the electromagnetic coupling portion of the second line, and the power transmitted to the second line is supplied to the load. Transmission equipment. The contactless power transmission device according to claim 1,
The second line of the power receiver has a second electromagnetic coupling portion that forms a loop and extends linearly,
The power receiver further includes a third line having an electromagnetic coupling portion extending in an extending direction of the second electromagnetic coupling portion of the second line,
The electromagnetic coupling portion of the third line overlaps the second electromagnetic coupling portion of the second line with a gap and is electromagnetically coupled, so that the power transmitted to the second line is the second A non-contact power transmission device that is transmitted from a track to a third track. The contactless power transmission device according to claim 3,
The power receiver is provided with a load on an AC power supply side of the electromagnetic coupling portion of a third line, and the power transmitted to the third line is supplied to the load. Transmission equipment. The contactless power transmission device according to claim 3 or 4,
The contactless power transmission device according to claim 1, wherein the power receiver is provided on a terminal side of the power transmission line, and another power receiver is provided on a front side thereof. In the non-contact electric power transmission apparatus in any one of Claims 1-5,
At least the electromagnetic coupling portion and the first line of the second line are thin plate-shaped, and are arranged so as to overlap on the broad side. The contactless power transmission device according to claim 6,
The second line reduces the electric power transmitted while keeping the gap with the first line constant by shifting the electromagnetic coupling portion in the width direction from the first line. apparatus. In the non-contact electric power transmission apparatus in any one of Claims 1-7,
The non-contact power transmission device, wherein the power transmission line is fixed to a passage or a road, and the power receiver receives power from the power transmission line while moving. In the non-contact electric power transmission apparatus in any one of Claims 1-8,
The contactless power transmission apparatus according to claim 1, wherein the electromagnetic coupling portion of the second line is provided with a protruding portion protruding in the width direction so that an inductive component and / or a capacitive component is added. The contactless power transmission device according to claim 9,
The protrusion is connected to a ground conductor at a tip thereof so that an inductive component is added thereto.   The contactless power transmission apparatus according to claim 10, wherein one protrusion is provided near a center. In the non-contact electric power transmission apparatus in any one of Claims 1-11,
The contactless power transmission device according to claim 1, wherein at least the electromagnetic coupling portion of the second line is made of a metamaterial.

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