JP6167823B2 - Non-contact power feeding device - Google Patents

Description

  The present invention relates to a non-contact power feeding device.

  In a system that sends an electromagnetic field to a moving moving body and receives electric energy on the moving body side using electromagnetic induction, the ground-side coil has a plurality of wires of the same width so as to cross the moving direction of the moving body. The three wirings arranged in parallel are similarly bent in a rectangular wave shape, and these three wirings are connected at a common neutral point. Further, a circuit in which a three-phase alternating current shifted by 120 degrees is applied to three wirings is disclosed (Patent Document 1).

US Patent Application Publication No. 2012/55751

  However, in the above system, the phase speed of the combined magnetic field generated by energizing the coil on the ground side is sufficiently high compared to the speed of the moving body, so the magnetic field viewed from the moving body running on the coil. The strength of is uniform regardless of the location of the coil. Therefore, there is a problem that an unnecessary magnetic field is generated in addition to the position of the moving body.

  The problem to be solved by the present invention is to provide a non-contact power feeding device that suppresses generation of an unnecessary magnetic field.

  In the present invention, a plurality of regular coils are arranged at a predetermined pitch along the traveling direction, and among magnetic fields generated by energizing the plurality of coils, a magnetic field component directed to the receiving coil is obtained. The power transmission coil is configured to have a different distribution for each of the plurality of areas with respect to the moving direction of the moving body, and the above problem is solved by controlling the alternating current supplied to the power transmission coil.

  According to the present invention, by synthesizing different magnetic field distributions in a plurality of coils, the combined magnetic field in a specific part of the region where the power transmission coil is arranged becomes larger than the other part. By generating a magnetic field, it is possible to suppress the generation of the magnetic field in unnecessary portions.

It is the block diagram which showed the principal part of the non-contact electric power feeding system which concerns on embodiment of this invention. FIG. 2A is a plan view of a vehicle including a power receiving coil, and FIG. 2B is a plan view of the power transmitting coil. FIG. 3A is a plan view of the coil unit, FIG. 3B is a plan view of the coil unit, and FIG. 3C is a plan view of the coil unit. It is a top view of a coil unit. FIG. 5A is a graph showing the characteristics of the magnetic field component in the z direction. FIG. 5B is a table showing the relationship between the coil area and the magnetic field strength. It is a top view of a coil unit. FIG. 7A is a graph showing the characteristics of the magnetic field component in the z direction. FIG. 7B is a table showing the relationship between the coil area and the magnetic field strength. It is a top view of a coil unit. FIG. 9A is a graph showing the characteristics of the magnetic field component in the z direction. FIG. 9B is a table showing the relationship between the coil area and the magnetic field strength. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is a top view of the power transmission coil of the non-contact electric power feeding system which concerns on other embodiment of this invention. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is a top view of the power transmission coil of the non-contact electric power feeding system which concerns on other embodiment of this invention. FIG. 17A is a table showing the relationship between the coil area and the magnetic field strength in the first embodiment. FIG. 17B is a table showing the relationship between the coil area and the magnetic field strength in the present embodiment. FIG. 18A is a graph showing the strength characteristics of the combined magnetic field in the first embodiment. FIG. 18B is a graph showing the strength characteristics of the combined magnetic field in the present embodiment. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is a top view of the power transmission coil of the non-contact electric power feeding system which concerns on other embodiment of this invention. 24 (a) is a plan view of the coil unit, FIG. 24 (b) is a plan view of the coil unit, FIG. 24 (c) is a plan view of the coil unit, and FIG. 24 (d) is a single view. 3 is a plan view of a coil 400. FIG. It is a top view of the power transmission coil of the non-contact electric power feeding system which concerns on other embodiment of this invention. FIG. 26A is a plan view of the coil unit, FIG. 26B is a plan view of the coil unit, and FIG. 26C is a plan view of the coil unit. It is a top view of the power transmission coil of the non-contact electric power feeding system which concerns on other embodiment of this invention. It is the graph which showed the intensity | strength characteristic of the synthetic magnetic field to z direction with respect to the position of x direction. It is a top view of the power transmission coil which concerns on the modification of this invention. It is a figure for demonstrating the overlap of the coil which comprises a power transmission coil, Comprising: Fig.30 (a) is a top view of a coil part, FIG.30 (b) is a top view of a coil unit, FIG.30 (c) ) Is a plan view of the power transmission coil. FIG. 31A is a plan view of the first coil portion, and FIG. 31B is a plan view of the second coil portion. FIG. 32A is a plan view of the first coil portion, and FIG. 32B is a plan view of the second coil portion. It is the graph which showed the intensity | strength characteristic of the magnetic field to az direction with respect to the position of ax direction. It is the graph which showed the intensity | strength characteristic of the magnetic field to az direction with respect to the position of ax direction. It is the graph which showed the intensity | strength characteristic of the magnetic field to az direction with respect to the position of ax direction. It is a top view of the 1st coil part contained in the power transmission coil of the non-contact electric supply system concerning other embodiments of the present invention.

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

<< First Embodiment >>
FIG. 1 is a configuration diagram showing a main part of a non-contact power feeding system according to an embodiment of the present invention. The non-contact power feeding system according to the present embodiment includes a high-frequency AC power supply unit 6, a non-contact power feeding unit 5 that performs non-contact power feeding of power output from the high-frequency AC power circuit 6, and a non-contact power feeding unit 5. A load section 7 to be supplied and a controller 8 are provided. The non-contact power supply system of this example is a system that uses a magnetic coupling action to supply electric power in a non-contact manner from a ground side having a power source to a battery such as a battery or a motor of a running vehicle. is there. In the non-contact power supply system, the high-frequency AC power supply unit 6 and the power transmission circuit unit 1 corresponding to the primary device are provided on the ground side. On the other hand, the power receiving circuit unit 2 and the load unit 7 corresponding to the secondary device are provided on the vehicle side.

  The high-frequency AC power supply unit 6 is connected to the three-phase AC power supply 64, the three-phase AC power supply 64, the rectifier 61 that rectifies the three-phase AC to DC, and the rectifier 61 via the smoothing capacitor 62 to be rectified. And a voltage type inverter 63 that converts current into high frequency power.

  The rectifier 61 connects the diode 61a and the diode 61b, the diode 61c and the diode 61d, and the diode 61e and the diode 61f in parallel, and connects the output of the three-phase AC power supply 64 to each intermediate connection point. The voltage type inverter 63 connects in parallel a series circuit of a switching element 63b similar to a switching element 63a that connects a diode to a MOSFET power transistor or the like in antiparallel, and a series circuit of a similar switching element 63c and switching element 63d. Then, it is connected to the rectifier 61 through the smoothing capacitor 62. Then, an intermediate connection point between the switching element 63a and the switching element 63b and an intermediate connection point between the switching element 63c and the switching element 63d are connected to the power transmission circuit unit 3 that is the primary side of the non-contact power feeding unit 5, respectively. The voltage type inverter 63 supplies AC power to the non-contact power feeding unit 5 at a driving frequency of about several k to several hundred kHz. This drive frequency is the frequency of the high-frequency current output from the high-frequency AC power supply unit 6.

  The non-contact power supply unit 5 includes a power transmission circuit unit 1 that is an input side (primary side) of the transformer and a power reception circuit unit 2 that is an output side (secondary side) of the transformer. The power transmission circuit unit 1 includes a primary winding 10 and a capacitor 11 connected in parallel to one power transmission coil 10. The power receiving circuit unit 2 includes a power receiving coil 20, a capacitor 21 connected in parallel to the power receiving coil 20, and a capacitor 22 connected in series to a parallel circuit of the power receiving coil 20 and the capacitor 21.

  The power transmission circuit unit 1 and the power reception circuit unit 2 are resonance circuits, and the circuit design of the resonance circuit is made so that the resonance frequency matches the drive frequency of the high-frequency AC power supply unit 6. The power transmission circuit unit 1 and the power reception circuit unit 2 are not limited to the above-described resonance circuit, and may be other resonance circuits.

  The load unit 7 includes a rectification unit 71 that rectifies AC power supplied from the non-contact power supply unit 5 into a direct current, and a load 72 that is connected to the rectification unit 71. The rectifying unit 71 connects the diode 71a and the diode 71b, and the diode 71c and the diode 71d in parallel, and connects the output of the power receiving circuit unit 4 to each intermediate connection point. Then, the output of the rectifying unit 71 is connected to the load 72. The load 72 is a battery provided in the vehicle or a motor provided in the vehicle.

  The controller 8 controls the alternating current that flows from the high-frequency AC power supply unit 6 to the power transmission circuit unit 1 by controlling on and off of the switching elements 63a to 63d. The controller 8 controls the alternating current according to the position of the vehicle on the travel path provided with the power transmission coil 10. The position of the vehicle may be detected by a sensor provided on the traveling road. Alternatively, the controller 8 may detect the position of the vehicle by receiving a signal transmitted from the vehicle (for example, a signal for starting the system or a signal indicating the position of the vehicle).

  Next, the structure of the power transmission coil 10 and the power reception coil 20 is demonstrated using FIG.2 and FIG.3. FIG. 2A is a plan view of the power receiving coil, and FIG. 2B is a plan view of the power transmitting coil. FIG. 3 is a plan view showing each coil after dividing the three coil units constituting the power transmission coil, FIG. 3A is a plan view of the coil unit 100, and FIG. FIG. 3C is a plan view of the coil unit 200, and FIG. 3C is a plan view of the coil unit 300.

  In FIG. 2, the x direction indicates the traveling direction of the vehicle, and the y direction indicates the width direction of the vehicle. 2B and 3, the high-frequency AC power supply unit 6 is illustrated with the rectifier 61 and the like omitted. In FIG. 2, in order to make it easy to understand the overlap of the coil units, the positions of the coil units 100 to 300 are shifted. However, in the actual power transmission coil 10, each unit is viewed from the z direction. The coil units 100 to 300 are arranged such that the outer peripheries overlap.

  In FIG. 3, the arrows shown in the loop-shaped coil indicate the direction of current. 3A to 3C, the capacitor 11 and the high-frequency AC power supply unit 6 are connected to each coil unit. However, the high-frequency AC power supply unit 6 may be a single common power supply. The capacitor 11 may be a common circuit element.

  As shown to Fig.2 (a), the receiving coil 20 is a rectangular coil, and is provided along the chassis of a vehicle. About the magnitude | size of the receiving coil 20, the length to the advancing direction of a vehicle is below the full length of a vehicle at least, and the length to the width direction of a vehicle is below the width of a vehicle. The coil surface of the receiving coil 20 is parallel to the xy plane.

  The power transmission coil 10 is provided on the traveling road surface so that the coil surface is parallel to the xy plane. The power transmission coil 10 includes three coil units 100, 200, and 300 that are stacked in the z direction. Regarding the size of the power transmission coil 10, the length in the x direction, which is the traveling direction of the vehicle, is sufficiently longer than the length in the x direction of the power reception coil 20, and the length in the y direction is y of the power reception coil 20. It is the same as the length of the direction.

  Each coil unit 100, 200, 300 has a plurality of loop-shaped coils by bending a conducting wire. And the area of a loop-shaped coil is formed so that it may differ for every coil unit 100,200,300.

  The three coil units 100, 200, and 300 are connected to a high-frequency AC power supply unit 6 that functions as a single-phase AC power supply. The frequency, amplitude, and phase of the alternating current flowing through the coil units 100, 200, and 300 are the same. The frequency of the alternating current corresponds to each frequency. Hereinafter, the term “frequency” also includes angular frequency.

  As shown in FIG. 3A, the coil unit 100 includes two loop-shaped coils 101 and 102 formed by intersecting the conductors in the xy plane and intersecting the conductors. The outer periphery of the coil unit 100 is rectangular. And the part 103 which a conducting wire crosses is one, and is located in a rectangular-shaped center part. As a result, the two loop-shaped coils 101 and 102 are arranged with the portion 103 where the conducting wires intersect with each other as a boundary. Further, the two loop-shaped coils are arranged along the x direction.

  Moreover, the coil unit 100 is comprised by bending one conducting wire. One conductor may be a single wire or a plurality of stranded wires. The number of turns of the coil portion is not particularly limited.

  When an alternating current (I · sin (ωt) is passed through the coil unit 100, where I is the current amplitude, ω is the angular frequency of the high-frequency AC power source, and t is the time), in the loop coil 101, the alternating current is The coil 102 flows in the clockwise direction, and the alternating current flows in the coil 102 counterclockwise. That is, in the loop-shaped coils adjacent in the x direction, the conduction directions of the alternating current flowing in the loop shape are opposite to each other with the intersecting portion 103 as a boundary.

  As shown in FIG. 3B, the coil unit 200 includes four loop-shaped coils 201, 202, 203, and 204 formed by intersecting conductive wires in the xy plane. The outer periphery of the coil unit 200 is rectangular and has the same shape as the outer periphery of the coil unit 100. The crossing portions 205, 206, and 207 of the conducting wires are three, and are aligned at equal distances in the x direction, and are located at the midpoint of the length in the width direction of the coil unit 200 in the y direction. Thereby, the four loop-shaped coils 201-204 are arranged on the boundary between the parts 205-207 where the conducting wires intersect. The coil unit 200 is also configured by bending a single conducting wire.

  When an alternating current (I · sin (ωt)) is passed through the coil unit 200, the conduction direction of the current is clockwise in the loop coils 201 and 203 and counterclockwise in the loop coils 202 and 204. Become.

  As illustrated in FIG. 3C, the coil unit 300 includes eight loop-shaped coils 301 to 308 formed by intersecting the conductive wires in the xy plane. The outer periphery of the coil unit 300 is rectangular and has the same shape as the outer periphery of the coil units 100 and 200. There are seven intersecting portions 309 to 315 of the conducting wires, which are aligned at equal distances in the x direction, and are located at the midpoint of the length in the width direction of the coil unit 200 in the y direction. Thus, the eight loop-shaped coils 301 to 308 are arranged with the portions 309 to 315 where the conductors intersect with each other as a boundary. The coil unit 300 is also configured by bending a single conducting wire.

  When an alternating current (I · sin (ωt)) is passed through the coil unit 300, the current conduction direction is clockwise in the loop-shaped coils 301, 303, 305, 307, and the loop-shaped coils 302, 304, 306 and 308 are counterclockwise.

  The coil units 100, 200, and 300 form a plurality of loop-shaped coils by intersecting conductive wires in the x direction in accordance with a predetermined pitch unit. The pitch unit indicates the unit of the length of the coil in the x direction. The pitch unit indicates the length in the x direction of the pair of coils 101 and 102 whose current conduction directions are opposite to each other.

The pitch unit (λ ₁ ) of the coil unit 100 corresponds to the total length in the x direction of the portion of the power transmission coil 10 that functions as a coil. The pitch unit (λ ₂ ) of the coil unit 200 is half the pitch unit (λ ₁ ). The pitch unit (λ ₃ ) of the coil unit 300 is a quarter length of the pitch unit (λ ₁ ).

ただし、λ_１は１番目のコイルユニットのピッチ単位であり、送電コイル１０のｘ方向への全長に相当する。 That is, when N coil units are stacked in order from a unit with a long pitch unit, 2 ^N-1 loop-shaped coils are formed in the Nth coil unit, and the Nth coil unit The pitch unit (λ _n ) is expressed by the following formula (1).

However, (lambda) ₁ is a pitch unit of the 1st coil unit, and is equivalent to the full length to the x direction of the power transmission coil 10. FIG.

  Next, the magnetic field distribution generated in the coil unit 100 will be described with reference to FIGS. 4 and 5. FIG. 4 is a plan view of the coil unit 100. FIG. 5A is a graph showing the characteristics of the magnetic field component in the z direction. The horizontal axis indicates the position in the x direction, and the vertical axis indicates the magnetic field strength (Bz) in the z direction. FIG. 5B is a table showing the relationship between the areas of the coils 101 and 102 and the magnetic field strength. 4A and 5B, “A” indicates a region of the coil surface of the coil 101, and “B” indicates a region of the coil surface of the coil 102.

  In a state where a constant voltage is applied to the coil unit 100, the conduction direction of the alternating current flowing through the coil 101 is clockwise. Therefore, in area A, the direction of the magnetic field in the direction perpendicular to the coil surface is the positive direction of the z-axis in FIG. The magnetic field strength in the z direction (direction perpendicular to the coil surface) is a. Further, the conduction direction of the alternating current flowing through the coil 102 is counterclockwise. Therefore, in area B, the direction of the magnetic field directed in the direction perpendicular to the coil surface is the negative direction of the z-axis in FIG. 4, and the magnetic field strength is −a.

  A magnetic field distribution generated in a state where the coil unit 200 is overlaid on the coil unit 100 will be described with reference to FIGS. 6 and 7. FIG. 6 is a plan view of the coil units 100 and 200. FIG. 7A is a graph showing the characteristics of the magnetic field component in the z direction. The horizontal axis indicates the position in the x direction, and the vertical axis indicates the magnetic field strength (Bz) in the z direction. FIG. 7B is a table showing the relationship between the areas of the coils 201 to 204 and the magnetic field strength. 6A and 7B, “A” indicates the area of the coil surface of the coil 201, “B” indicates the area of the coil surface of the coil 202, “C” indicates the area of the coil surface of the coil 203, and “D”. "Indicates the area of the coil surface of the coil 204. 7A shows the characteristics of the magnetic field generated from the coil unit 100, and graph b shows the characteristics of the magnetic field generated from the coil unit 200. FIG.

  When a constant voltage is applied to the coil unit 200, the conduction direction of the alternating current flowing through the coil 201 and the coil 203 is clockwise, and the conduction direction of the alternating current flowing through the coil 202 and the coil 204 is counterclockwise. Therefore, in areas A and C, the magnetic field strength in the z direction is a. In areas B and D, the magnetic field intensity in the z direction is -a. A magnetic field generated from the coil unit 200 is shown as a graph b in FIG.

  As shown in FIG. 6, since the coil unit 100 and the coil unit 200 overlap, the magnetic fields generated by the coil units are synthesized. As shown in FIG. 7, in area A, both the magnetic field components in the z direction generated by the coil unit 100 and the coil unit 200 are a. For this reason, the combined magnetic field in area A strengthens toward the positive direction of the z-axis. In area D, both the magnetic field components in the z direction generated by the coil unit 100 and the coil unit 200 are -a. Therefore, the composite magnetic field in area A strengthens toward the negative direction of the z axis.

  On the other hand, in areas C and D, the magnetic field generated by the coil unit 100 and the magnetic field generated by the coil unit 200 are opposite to each other with the same intensity. Therefore, the magnetic fields generated in areas C and D cancel each other, and the combined magnetic field becomes zero.

That is, in the unit in which the coil unit 100 and the coil unit 200 are overlapped, when an alternating current is passed, the magnetic field obtained by synthesizing the z-direction magnetic field components reinforces for each region divided by the pitch unit (λ ₂ ). It has a part and a weakening part.

  A magnetic field distribution generated in a state where the coil units 200 and 300 are superimposed on the coil unit 100 will be described with reference to FIGS. 8 and 9. FIG. 8 is a plan view of the coil units 100, 200, 300. FIG. 8A is a graph showing the characteristics of the magnetic field component in the z direction. The horizontal axis indicates the position in the x direction, and the vertical axis indicates the magnetic field strength (Bz) in the z direction. FIG. 7B is a table showing the relationship between the areas of the coils 301 to 308 and the magnetic field strength. “A” to “H” in FIGS. 6 and 7 indicate regions of the coil surfaces of the coils 301 to 308, respectively. 7A shows the characteristics of the magnetic field generated from the coil unit 100, the graph b shows the characteristics of the magnetic field generated from the coil unit 200, and the graph c shows the characteristics of the magnetic field generated from the coil unit 300. Show.

  With a constant voltage applied to the coil unit 300, the conduction direction of the alternating current flowing through the coils 301, 303, 305, 307 is clockwise, and the conduction direction of the alternating current flowing through the coils 302, 304, 306, 308 is Turns counterclockwise. Therefore, in areas A, C, E, and G, the magnetic field strength in the z direction is a. In areas B, D, F, and H, the magnetic field strength in the z direction is −a. The magnetic field generated from the coil unit 300 is shown as a graph c in FIG.

  As shown in FIG. 8, since the coil unit 100 and the coil units 200 and 300 overlap each other, the magnetic fields generated by the coil units are combined. As shown in FIG. 9, in area A, the magnetic field components in the z direction generated by the coil unit 100, the coil unit 200, and the coil unit 300 are all a. Therefore, the combined magnetic field in area A is most intensified in the positive direction of the z-axis as compared with the combined magnetic field in other areas. Similarly, in the area H, the magnetic field components in the z direction generated by the coil unit 100, the coil unit 200, and the coil unit 300 are all -a. For this reason, the combined magnetic field in area H strengthens most toward the negative direction of the z-axis.

  In the other areas B to G, the magnetic fields generated from the two coil units among the three coil units are directed in opposite directions to each other, so that the combined magnetic fields in the respective areas are weakened. Therefore, the combined magnetic field of areas B to G is smaller than the combined magnetic field of area A.

  FIG. 10 shows the intensity characteristics of the combined magnetic field in the z direction with respect to the position in the x direction. A to H shown on the horizontal axis of FIG. 10 correspond to A to H shown in FIG. As shown in FIG. 10, the combined magnetic field in area A is highest in the positive direction. Moreover, as shown in FIG. 9, the magnetic field components in the z direction generated from the coil units 100, 200, and 300 are in a symmetrical relationship between the areas A to D and the areas E to H. Therefore, the strength characteristic of the composite magnetic field in the z direction has an antiphase with the boundary between the area D and the area E as a boundary, and the composite magnetic field in the area H becomes the lowest in the negative direction.

As described above, in the unit in which the coil units 100, 200, and 300 are overlapped, when an alternating current is passed, the magnetic field obtained by synthesizing the z-direction magnetic field component is divided into half of the pitch unit (λ ₃ ). It has a strengthening part and a weakening part.

In the above description, the combined magnetic fields in the z direction are described for the case where two coil units are overlapped and the case where three coil units are overlapped, but when N coil units are overlapped, Is defined by the pitch unit (λ _n ) of the N-th coil unit. That is, the composite magnetic field of the Nth coil unit is strengthened for each region corresponding to the shortest pitch unit (λ _n ), in other words, for each coil surface of the loop coil of the pitch unit (λ _n ). It will have a weakening part.

  And the non-contact electric power feeding system of this example controls the alternating current sent through the power transmission coil 10 by the controller 8 according to the position of the vehicle on a power feeding path, comprising the power transmission coil 10 as mentioned above. Specifically, the controller 8 detects the position of the vehicle using a sensor or the like, and the AC power supply flows to the power transmission coil 10 when the vehicle including the power receiving coil 20 enters the area A of the power transmission coil 10. Next, the high-frequency AC power supply unit 6 is controlled. At this time, the controller 8 makes the amplitude and phase of each AC current flowing from the AC wave AC power supply 6 to each of the coil units 100 to 300 the same. Thereby, in each area of the power transmission coil 10, a reinforcing magnetic field toward the power reception coil 20 is generated in the area A facing the power reception coil 20. Further, in the areas B to G not facing the power receiving coil 20, the magnetic fields are weakened.

As described above, in this example, the parallel wires (feeding path) parallel to the coil surface of the power receiving coil 20 are formed by crossing the conductor wires in accordance with the pitch units (λ ₁ , λ ₂ , λ ₃ ) along the traveling direction of the vehicle. Power transmission coil 10 is composed of a plurality of coil units 100 to 300 each having a plurality of loop-shaped coils formed by intersecting conductors, and the plurality of coil knits 100 to 300 are overlapped in the z direction. Each pitch unit has a different length. In this example, an alternating current having the same amplitude is supplied to each coil unit, and a current flowing in the plurality of coils 101, 102, 201-204, 301-308 in a state where a constant voltage is applied to the conducting wire. The power transmission coil 10 is configured to flow in the opposite directions with respect to the conduction directions of the conductors at the intersections 103, 205 to 207, and 309 to 315 of the conductors.

  As a result, in the present example, on the xy plane, coils that form a clockwise current loop and coils that form a counterclockwise current loop are arranged in units of pitch. Therefore, it is possible to cancel a magnetic field (far field) that causes noise at a point sufficiently away from the position where the power transmission coil 10 is installed.

  In this example, the pitch units are different for each of the coil units 100 to 300 stacked in the z direction. Therefore, the combined magnetic field generated by each unit strengthens toward the z direction in a specific region. In other regions, the magnetic field components in the z direction weaken each other. As a result, the strength of the near magnetic field in a specific portion can be increased, and the near magnetic field strength in another unnecessary portion can be reduced.

Further, in this example, a magnetic field along the z direction is formed for each of the plurality of coils on the loop-shaped coil surface, and the combined magnetic field of the magnetic field component in the z direction is strengthened and weakened for each predetermined region. And have The predetermined region is made to correspond to the looped coil surface of the coil unit having the shortest pitch unit (λ _n ).

Thereby, this example can form the part which raises a near magnetic field, and the part which weakens a near magnetic field for every loop-shaped coil surface of a coil unit with the shortest pitch unit ((lambda) _n ). As a result, generation of an unnecessary magnetic field can be suppressed.

  Further, in this example, the power transmission coil 10 is composed of the Nth coil units in order from the long coil unit in the pitch unit, while the length from the first pitch unit to the Nth pitch unit is expressed by the formula. (1) is satisfied. As a result, the z-direction magnetic field pattern generated in each unit is synchronized, so that a portion that increases and weakens the near magnetic field can be generated in a region corresponding to half the length of the Nth pitch unit. As a result, generation of an unnecessary magnetic field can be suppressed.

  In this example, it is not necessary to limit the number of the coil units 100 to 300 to one, and a plurality of the coil units 100 to 300 may be provided, and the longitudinal portions of the coil units 100 to 300 may be arranged along the x axis.

  The controller 8 corresponds to the “current control means” of the present invention.

<< Second Embodiment >>
FIG. 11 is a plan view of a power transmission coil of a non-contact power feeding system according to another embodiment of the present invention. In this example, the shape of the power transmission coil 10 is the same as that of the first embodiment described above, but the point of controlling the phase of the alternating current flowing from the high-frequency AC power supply unit 6 to each coil unit of the power transmission coil 10 is different. Other configurations are the same as those in the first embodiment described above, and the description thereof is incorporated. Areas A to H shown in FIG. 11 are the same as areas A to H shown in FIG.

The high-frequency AC power supply unit 6 outputs three-phase AC power supplies having different phases to the three coil units 100 to 300, respectively. Phase of the AC current output from the high-frequency AC power source unit 6 to the coil unit 100 is set to phi _a, the phase of the alternating current output from the high-frequency AC power source unit 6 to the coil unit 200 is set to phi _b, high-frequency AC phase of the alternating current from the power supply unit 6 is output to the coil unit 300 is set to phi _c.

The controller 8 controls the phases (φ _a , φ _b , φ _c ) of the AC current that flows from the high-frequency AC power supply unit 6 to the coil units 100, 200, 300 according to the position of the vehicle traveling on the power feeding path. When the phase (φ _a ) is set to a predetermined phase among the phases of the alternating currents, the controller 8 sets the other phases (φ _b , φ _c ) to the same phase as the predetermined phase, or The other phases (φ _b , φ _c ) are set to phases opposite to the predetermined phases. Further, the controller 8 makes the amplitude and frequency of the alternating current flowing through the coil units 100, 200, 300 constant.

Next, the relationship between the phase of the alternating current (φ _a , φ _b , φ _c ) set by the controller 8 and the characteristics of the magnetic field in the z direction generated in the power transmission coil 10 will be described with reference to FIGS. Show. 12 to 15 show the strength characteristics of the combined magnetic field in the z direction with respect to the position in the x direction (vehicle traveling direction). The vertical axis | shaft of FIGS. 12-15 is the intensity | strength of the synthetic magnetic field which synthesize | combined the magnetic field component to z direction which generate | occur | produced in each coil unit 100-300. The horizontal axis indicates the position in the x direction.

FIG. 12 shows characteristics when all phases (φ _a , φ _b , φ _c ) are set to 0 °. When all the phases (φ _a , φ _b , φ _c ) are 0 ° (φ _a , φ _b , φ _c = 0 °), the combined magnetic field of each coil unit 100 to 300 is a part of area A Thus, they are most strengthened toward the positive direction of the z-axis. On the other hand, in the other areas B to G, the combined magnetic field weakens.

FIG. 13 shows characteristics when the phase (φ _a , φ _b ) is set to 0 ° and the phase (φ _c ) is set to 180 °. When the phases (φ _a , φ _b ) are both the same phase of 0 ° and the phase (φ _c ) is the opposite phase of 180 ° (φ _a , φ _b = 0 °, φ _c = 180 °) The combined magnetic field of each of the coil units 100 to 300 strengthens most in the area B portion in the positive direction of the z-axis. On the other hand, in the other areas A, C to F, and H, the combined magnetic field is weakened.

FIG. 14 shows characteristics when the phase (φ _a , φ _c ) is set to 0 ° and the phase (φ _b ) is set to 180 °. When the phases (φ _a , φ _c ) are the same phase of 0 ° and the phase (φ _b ) is the opposite phase of 180 ° (φ _a , φ _c = 0 °, φ _b = 180 °) The combined magnetic field of each of the coil units 100 to 300 is most intense in the area C portion in the positive direction of the z-axis. On the other hand, in the other areas A, B, D, E, G, and H, the combined magnetic fields weaken each other.

FIG. 15 shows characteristics when the phase (φ _a ) is set to 180 ° and the phases (φ _b , φ _c ) are set to 0 °. When the phases (φ _b , φ _c ) are both the same phase of 180 °, and the phase (φ _a ) is 0 ° of the opposite phase to the phases (φ _b , φ _c ) (φ _b , φ _c = 0 °, φ _a = 180 °), the combined magnetic field of each of the coil units 100 to 300 strengthens most in the area D portion in the positive direction of the z-axis. On the other hand, in the other areas A to C and F to H, the combined magnetic fields weaken each other.

As described above, by controlling the phase of the alternating current flowing through each unit, the part that strengthens the combined magnetic field most in the positive direction of the z-axis (the part that takes the peak value of the combined magnetic field) is directed in the x direction. Can be moved. Also in areas E to H, similarly to areas A to D, the controller 8 can move the most intensified portion of the combined magnetic field from area E to area H by controlling the phase of the alternating current. . In the areas E to H, the conditions of the phases (φ _a , φ _b , φ _c ) when the combined magnetic fields are most strengthened are opposite to the phase conditions set in the areas A to D. , You can set.

  The controller 8 specifies a coil facing the position of the power receiving coil 8 among a plurality of loop-shaped coils included in the power transmitting coil 10 using a sensor or the like. As for the position of the power receiving coil 8, a position sensor is provided in the power feeding path corresponding to each area, and the position of the power receiving coil 8 is detected by the sensor. Alternatively, the controller 8 detects the intrusion of the vehicle into the power feeding path using a sensor or the like, receives a signal from the vehicle, and acquires the vehicle speed of the vehicle. Then, the controller 8 calculates the timing at which the power reception coil 20 enters the areas A to H of the power transmission coil 10 from the time of entry of the vehicle into the power feeding path and the vehicle speed. Thereby, the controller 8 may detect the position of the power receiving coil 20. In addition, when the vehicle speed which drive | works a power feeding path is decided beforehand by regulation speed etc., the controller 8 does not need to acquire the information of a vehicle speed from the outside.

The controller 8 causes an alternating current to flow through each of the coil units 100 to 300 while setting the phase conditions to φ _a , φ _b , and φ _c = 0 ° at the timing when the power receiving coil 20 enters the area A of the power transmitting coil 10. . When the position of the power receiving coil 20 is within the area A, the phase condition is not changed from the conditions of φ _a , φ _b , φ _c = 0 °. Then, the controller 8 changes the phase condition to φ _a , φ _b = 0 °, φ _c = 180 ° at the timing when the position of the power receiving coil 20 moves from area A to area B of the power transmitting coil 10, and the alternating current Is passed through each coil unit 100-300.

  Furthermore, the controller 8 changes the phase condition at the timing when the position of the power receiving coil 20 moves between areas. Thereby, the controller 8 can match the peak portion of the combined magnetic field with the position of the moving vehicle.

  As described above, this example controls each phase of the alternating current that flows through each of the coil units 100 to 300 in accordance with the position of the vehicle traveling in the x direction. As a result, even when the vehicle moves on the power feeding path, the combined magnetic field (the combined magnetic field in the z direction) toward the power receiving coil 20 is strengthened according to the position of the power receiving coil 20, and the combined magnetic field is not provided at the portion other than the position of the vehicle. Can be weakened. As a result, this example can suppress the generation of a magnetic field in an unnecessary portion of the vehicle that does not face the power receiving coil 20.

  In this example, when the phase of the alternating current flowing through the coil unit 100 is set as the first phase and the phase of the alternating current flowing through the coil units 200 and 300 is set as the second phase, Depending on the position of the vehicle that travels, the second phase is set to the same phase or opposite phase to the first phase, thereby controlling the alternating current that flows through the coil units 200 and 300. As a result, even when the vehicle moves on the power feeding path, the combined magnetic field (the combined magnetic field in the z direction) toward the power receiving coil 20 is strengthened according to the position of the power receiving coil 20, and the combined magnetic field is not provided at the portion other than the position of the vehicle. Can be weakened. As a result, this example can suppress generation of a magnetic field in an unnecessary portion that does not face the power receiving coil 20 of the vehicle.

Further, in this example, the pitch unit of each of the coil units 100 to 300 is formed so as to satisfy the formula (1), and the area serving as a unit for controlling the phase is defined as the coil unit having the shortest pitch unit (λ _n ). It matches the looped coil surface. Therefore, when the position of the power receiving coil 8 is in each of the areas A to H, the controller 8 fixes the phase and amplitude of the alternating current, and the controller 8 moves when the position of the power receiving coil 20 moves between the areas. 8 changes the phase without changing the amplitude of the alternating current. Thereby, the number of times of phase switching can be minimized according to the position of the power receiving coil 20.

  In this example, the pitch units of the coil units 100 to 300 are formed so as to satisfy the formula (1), so that the area for controlling the phase of the alternating current is equally spaced in the x direction. If the vehicle speed is constant, the time interval for switching the phase is constant, so that the number of sensors for detecting the position of the vehicle can be reduced.

In this example, each phase (φ _a , φ _b , φ _c ) is set to 0 ° and 180 °, but may be set to an angle other than 0 ° and 180 °.

<< Third Embodiment >>
FIG. 16 is a configuration diagram showing a main part of a non-contact power feeding system according to another embodiment of the invention. In this example, the current path between the high-frequency AC power supply unit 6 and the power transmission coil 10 is different from that of the first embodiment described above. Other configurations are the same as those of the first or second embodiment described above, and the descriptions of the first and second embodiments are incorporated as appropriate. Areas A to H shown in FIG. 16 correspond to the coil surface of the loop-shaped coil constituting the coil unit 122.

The device on the power transmission side of the non-contact power feeding system of this example includes switches 31 to 37 in addition to the configurations of the power transmission circuit unit 1, the high-frequency AC power supply unit 6, and the controller 8. The power transmission coil 10 includes coil units 121 to 123, coil units 221 to 223, and coil units 321 to 323. The coil units 121 to 123 are coil units in which two looped coils are formed by crossing the conductors in accordance with the pitch unit (λ ₁ ). The shape of the coil units 121 to 123 is the same as that of the coil unit 100 according to the first embodiment.

The coil units 221 to 223 are coil units in which four looped coils are formed by intersecting conductive wires in accordance with a pitch unit (λ ₂ ). The shape of the coil units 221 to 223 is the same as that of the coil unit 200 according to the first embodiment.

The coil units 321 to 323 are coil units in which eight loop-shaped coils are formed by intersecting conductors in accordance with the pitch unit (λ ₃ ). The shape of the coil units 321 to 323 is the same as that of the coil unit 300 according to the first embodiment.

  In addition, the coil units 121 to 123, the coil units 221 to 223, and the coil units 321 to 323 are arranged in the z direction so as to be three layers. At this time, in the first layer, the coil units 121 to 123 are arranged along the xy plane so that the longitudinal direction of the unit is the traveling direction of the vehicle. In the second layer, the coil units 221 to 223 are arranged along the xy plane in the same manner as the coil units 121 to 123. In the third layer, the coil units 321 to 323 are arranged along the xy plane in the same manner as the coil units 121 to 123.

Furthermore, when the coil units are stacked, the second layer coil units 221 to 223 are half the pitch unit (λ ₁ ), in the negative direction of the x axis, relative to the first layer coil units 121 to 123. It's off. Further, the third layer coil units 321 to 323 are shifted from the second layer coil units 221 to 223 by half the pitch unit (λ ₂ ) in the negative direction of the x-axis.

  In the example of FIG. 16, in order to easily illustrate the deviation of the coil units 121 to 123, 221 to 223, and 321 to 323, a state in which the units are not stacked in layers is illustrated. In the coil 10, the units are overlapped. In FIG. 16, three coil units in each layer are illustrated. However, the number of coil units is not limited to three, and may be four or more.

  The switches 31 to 37 are switches for switching electrical connection and disconnection between the high-frequency AC power supply unit 6 and the coil units 121 to 123, 222, 223, 322, and 323. Switching on and off of the switches 31 to 37 is controlled by the controller 8.

  The switch 31 is connected between the high-frequency AC power supply unit 6 and the coil unit 121, the switch 32 is connected between the high-frequency AC power supply unit 6 and the coil unit 122, and the switch 33 is connected to the high-frequency AC power supply unit 6 and the coil unit 123. Connected between and.

  The switches 34 and 35 are connected between the high-frequency AC power supply unit 6 and the coil units 222 and 223, respectively. The switches 36 and 37 are connected between the high-frequency AC power supply unit 6 and the coil units 322 and 323, respectively. Yes.

  The controller 8 controls the phase of the alternating current flowing from the high-frequency alternating current power supply unit 6 to each coil unit while switching on and off the switches 31 to 37 according to the position of the vehicle traveling on the power feeding path. The energizing range of the coil unit is controlled.

Next, a synthetic magnetic field in the z direction when an alternating current is passed through the coil units 121, 123, 221, 223, 321, and 323 while an alternating current is passed through the coil units 122, 222, and 322 will be described with reference to FIGS. This will be described with reference to FIG. However, each phase (φ _a , φ _b , φ _c ) of the alternating current flowing through the coil units 122, 222, and 322 is 0 °.

  FIG. 17 is a table showing the relationship between the area of the loop-shaped coil constituting each coil unit and the magnetic field strength. FIG. 18 shows the intensity characteristics of the combined magnetic field in the z direction with respect to the position in the x direction. FIG. 17A and FIG. 18A show, as a reference example, a combined magnetic field of the coil units 100 to 300 in the non-contact power feeding system according to the first embodiment. FIG. 17B and FIG. 18B show the combined magnetic field of this embodiment.

  The controller 8 turns on the switches 32, 34, and 36 while turning off the switches 31, 33, 35, and 37 in order to generate the combined magnetic field shown in FIGS. 17 (b) and 18 (b). In addition, the controller 8 controls the high-frequency AC power supply unit 6 so that AC currents having the same amplitude and phase flow through the coil units 122, 222, and 322.

  Referring to FIG. 8 of the first embodiment, in the reference examples, in areas E to H, alternating currents are respectively applied to the first layer coil unit 100, the second layer coil unit 200, and the third layer coil unit 300. Flowing. Therefore, as shown in FIG. 17A, a magnetic field is generated in the areas E to H of the second layer and the third layer. In particular, in the reference example, in area H, a magnetic field having an intensity of −a is generated in each layer.

  Further, the composite magnetic field characteristic according to the reference example has a peak value in the negative direction of the z-axis in the area H as shown in FIG.

  On the other hand, in the present embodiment, in areas E to H, an alternating current flows through the first layer coil unit 122 and does not flow through the second layer coil unit 223. In areas G and H, the alternating current flows only in the first layer coil unit 122 and does not flow in the second layer coil unit 223 and the third layer coil unit 323.

  Therefore, no magnetic field is generated in the areas E to H of the second-layer coil unit 223, and no magnetic field is generated in the areas G and H of the third-layer coil unit 323.

  And the characteristic of the synthetic magnetic field which concerns on this embodiment becomes like FIG.18 (b). In the area H, the magnetic field in the negative z-axis direction is not generated in the coil portions of the second and third layers. Therefore, as in the reference example, the composite magnetic field in the negative z-axis direction is strong in the area H. There is nothing.

Next, as described above, in the state where an alternating current is passed through the coil units 122, 222, 322 and an alternating current is not passed through the coil units 121, 123, 221, 223, 321, 323, The case where the phase of current (φ _a , φ _b , φ _c ) flowing through 222 and 322 is set will be described with reference to FIGS.

  19 to 22 show the intensity characteristics of the combined magnetic field in the z direction with respect to the position in the x direction (vehicle traveling direction). The vertical axis | shaft of FIGS. 19-22 is the intensity | strength of the synthetic | combination magnetic field which synthesize | combined the magnetic field component to z direction which generate | occur | produced in each coil unit 100-300. The horizontal axis indicates the position in the x direction. Areas A to H illustrated in FIGS. 19 to 22 correspond to the areas A to H in FIG. 16.

FIG. 19 shows characteristics when all the phases (φ _a , φ _b , φ _c ) are set to 0 °. When all the phases (φ _a , φ _b , φ _c ) are 0 ° (φ _a , φ _b , φ _c = 0 °), the combined magnetic field of each coil unit 122, 222, 322 is the area A In this part, they are strengthened most toward the positive direction of the z-axis.

When the phase conditions are φ _a , φ _b = 0 °, and φ _b = 180 °, the combined magnetic field has a peak value in the positive direction of the z-axis in area B as shown in FIG. When the phase conditions are φ _a , φ _c = 0 °, and φ _b = 180 °, the resultant magnetic field takes a peak value in the positive direction of the z axis in area C as shown in FIG. When the phase conditions are φ _b , φ _c = 0 °, and φ _a = 180 °, the resultant magnetic field has a peak value in the positive direction of the z-axis in area D as shown in FIG. Even if the phase condition is changed as described above, the composite magnetic field in the area H is lower than the peak value in the positive direction even if it is generated in the negative direction of the z-axis.

  As described above, by controlling the phase of the alternating current flowing through the coil units 122, 222, and 322 while maintaining the ON state of the switches 32, 34, and 36, the composite current is strengthened even between the areas A to H. The matching part can be moved in the x direction. In addition, when the portion where the combined current is strengthened is moved in the x direction between the areas E to H, each coil unit is energized in accordance with the position of the power receiving coil 20. Then, the controller 8 controls the phase of the alternating current when energized so that the magnetic field takes a peak value in the positive direction of the z-axis in an area corresponding to the position of the power receiving coil. Hereinafter, detailed control of the controller 8 will be described.

  The controller 8 turns on the switch 32 while switching the switch 31 from on to off at the timing when the power receiving coil 20 enters the area A of the coil unit 122 from the coil unit 121. Since the switches 34 and 36 are already turned on, the controller 8 does not switch the switches 34 and 36 on and off.

The controller 8 sets the phase condition to φ _a , φ _b , φ _c = 0 ° at the timing when the power receiving coil 20 enters the area A of the coil unit 122, and sets the alternating current to the coil units 122, 222, Run to 322.

At the timing when the position of the power receiving coil 20 moves from area A to area B of the coil unit 122, the phase condition is changed to φ _a , φ _b = 0 °, and φ _c = 180 °. Further, the phase condition is changed to φ _a , φ _c = 0 °, and φ _b = 180 ° at the timing when the position of the power receiving coil 20 moves from area B to area C of the coil unit 122. At the timing when the position of the power receiving coil 20 moves from the area C to the area D of the coil unit 122, the phase condition is changed to φ _b , φ _c = 0 °, and φ _a = 180 °.

Next, at the timing when the position of the power receiving coil 20 moves from area D to area E of the coil unit 122, the controller 8 turns on the switch 35 while switching the switch 34 off. Since the switch 36 is already in the on state, the controller 8 does not switch the switches 36 and 37 on and off. That is, when the position of the power receiving coil 20 is in the area E, the controller 8 controls the switches 31 to 37 so that the coil units 122, 223, and 322 corresponding to the position of the area E are energized. Further, the controller 8 sets the phase (φ _a , φ _b , φ _c ) to 180 ° so that the magnetic field in the positive z-axis direction generated by energization of the coil unit 122 takes a peak value at the position of the area E. , 180 °, and 0 °. As a result, the combined magnetic field is strengthened most in the positive direction of the z-axis in the area E portion.

At the timing when the position of the power receiving coil moves from area E to area F, the controller 8 switches the phase condition to φ _a , φ _c = 180 ° φ _b = 0 ° while maintaining the states of the switches 31 to 37.

At the timing when the position of the power receiving coil 20 moves from the area F to the area G of the coil unit 122, the controller 8 turns on the switch 37 while switching the switch 36 off. That is, when the position of the power receiving coil 20 is in the area G, the controller 8 controls the switches 31 to 37 so that the coil units 122, 223, and 323 corresponding to the position of the area G are energized. Further, the controller 8 sets the phase conditions of the alternating current flowing through the coil units 122, 223, and 323 to φ _a = 180 °, φ _b , and φ _c = 0 °. As a result, the combined magnetic field is strengthened most in the positive direction of the z axis in the area G.

At the timing when the position of the power receiving coil moves from the area G to the area H, the controller 8 changes the phase condition to φ _a , φ _b , φ _c = 180 ° while maintaining the state of the switches 31 to 37.

Next, a case where the first to Nth coil units are sequentially stacked up to N layers will be described. However, N is a natural number of 2 or more. In the first layer coil unit, a plurality of coil units having the same shape as the first coil unit are arranged on the xy plane, and these coil units are arranged so that the longitudinal direction is along the x direction. Yes. Pitch unit of the plurality of coil units arranged in the first layer becomes lambda _1. And the switch similar to the switches 31-33 is connected between the coil unit arrange | positioned at the 1st layer and the high frequency alternating current power supply part 6, respectively.

The controller 8 sets an energization range in which an alternating current is passed through the conducting wire in the first layer by controlling on and off of the switches connected to the coil units in the first layer. At this time, the energization range is divided every pitch unit (λ ₁ ).

Of the second to Nth coil units, the Mth coil unit makes the pitch unit (λ _M ) half of the pitch unit (λ _M-1 ) of the _M− 1th coil unit. However, M is a continuous natural number of 2 or more and N or less. The Mth coil unit is arranged so as to overlap the M-1th coil unit in the z direction. In the M-th layer coil unit, a plurality of coil units having the same shape as the M-th coil unit are arranged in the xy plane, and these coil units are arranged in the same manner as the M-1 layer.

The Mth coil unit is arranged so as to be shifted in the x direction by a half of the pitch unit (λ _M−1 ) of the _M− 1th coil unit. Further, when the Mth coil unit is shifted in the x direction with respect to the M-1th coil unit, a loop-like coil included in the M-1th coil unit and an Mth coil unit are included. The looped coils are arranged so as to overlap each other on at least one looped coil surface. Similarly, the other coil units included in the M-th layer are arranged by being shifted in the x direction by half of the pitch unit (λ _M−1 ).

Switches similar to the switches 34 to 37 are connected between the coil unit arranged in the Mth layer and the high-frequency AC power supply unit 6. The energization range determined by turning on and off the switch by the controller 8 is divided for each pitch unit (λ _M ). Since the M−1th coil knit and the Mth coil unit are shifted in the x direction by a half of the pitch unit (λ _M−1 ), the energization range corresponding to the size of the coil unit is also the same. It will shift.

  The controller 8 controls on / off of each switch connected between each coil unit and the high-frequency AC power supply unit 6 according to the position of the power receiving coil 20. Controls the phase of the alternating current flowing through the.

  The timing for switching the switch is determined by the positional relationship between the power receiving coil 20 and the energization range of each coil unit. That is, the controller 8 energizes the energization range located in the negative z-axis direction with respect to the position of the power receiving coil 20 in the z-axis direction (in other words, energization including the x and y-axis coordinates indicating the position of the power receiving coil 20. For the range), a switch corresponding to the energization range is turned on so that an alternating current flows, and other switches are turned off so that an alternating current does not flow in the energization range not including the position of the power receiving coil.

Further, the timing for switching the phase to the same phase or the opposite phase is determined by the positional relationship between the range divided by the half length of the pitch unit (λ _N ) and the power receiving coil 20. The range divided by half of the pitch unit (λ _N ) corresponds to a single looped coil surface included in the Nth coil unit.

The controller 8 specifies a range located in the negative direction of the z-axis with respect to the position of the power receiving coil 20 in each layer in a range divided by half of the pitch unit (λ _N ). Then, the controller 8 controls the phase of the alternating current flowing through the coil unit of each layer so that the magnetic field in the positive direction of the z-axis is strengthened by the loop-shaped coil of each layer including the specified range.

As a result, in this example, in the energization range corresponding to the coil unit, the most intense part of the combined magnetic field in the positive direction of the z-axis with respect to the range divided by half of the pitch unit (λ _N ). It is possible to move the strongest portion of the combined magnetic field in the x direction according to the position of the vehicle.

As described above, in this example, the first to Nth coil units are arranged so as to overlap in the z direction, and the energization ranges of these coil units are arranged so as to overlap at least one loop-shaped coil surface. . In this example, the energization range of the Mth coil unit is shifted in the x-axis direction by a half length of the pitch unit (λ _M-1 ) with respect to the energization range of the M−1th coil unit. . As a result, the energization range is shifted in each layer, so that the symmetry of the composite magnetic field can be canceled, and the magnetic field is weakened in a region that does not require the generation of a strong magnetic field while eliminating the part that strengthens the magnetic field in the opposite phase. The part can be taken widely.

  Moreover, this example controls the timing which supplies an alternating current to an energization range according to the position of the traveling vehicle. Thereby, the part which a magnetic field strengthens can be moved according to the movement of a vehicle. As a result, the strength of the near magnetic field in a specific portion can be increased, and the near magnetic field strength in another unnecessary portion can be reduced.

<< 4th Embodiment >>
FIG. 23 is a configuration diagram showing a main part of a non-contact power feeding system according to another embodiment of the invention. This example is different from the first embodiment described above in that a single loop-shaped coil 400 is provided in the power transmission coil 10. The other configuration is the same as that of the first embodiment described above, and the descriptions of the first to third embodiments are incorporated as appropriate. In FIG. 23, the positions of the coil units 100 to 300 and the single coil 400 are shifted in order to make it easy to understand the overlapping of the coil units 100 to 300 and the single coil 400. 10, the coil units 100 to 300 and the single coil 400 are arranged so that the outer peripheries of the units and the single coil 400 overlap when viewed from the z direction.

  As shown in FIG. 23, the power transmission coil 10 includes coil units 100 to 300 and a loop-shaped coil 400. The outer periphery of the loop-shaped single coil 400 has the same shape as the outer periphery of the coil units 100 to 300 in the xy plane. Further, the single coil 400 is overlapped in the z direction so that the coil surface of the single coil 400 faces the coil surface of each unit while aligning the outer periphery with the outer periphery of the coil units 100 to 300.

  FIG. 24 shows a plan view of each coil in a state where the coil unit 100 and the single coil 400 on which the power transmission coil 10 overlaps are separated. 24A is a plan view of the coil unit 100, FIG. 24B is a plan view of the coil unit 200, FIG. 24C is a plan view of the coil unit 300, and FIG. A plan view of the coil 400 is shown. In FIGS. 24A to 24D, the high-frequency AC power supply unit 6 and the capacitor 11 are connected to each unit and the single coil 400, respectively. A common power supply may be used, and the capacitor 11 may be a common circuit element. In FIG. 24, the arrow shown in the loop-shaped coil represents the direction of current.

  As shown in FIG. 24D, the single coil 400 is a coil in which one conductive wire is formed in a loop shape, and does not cross like the coil units 100 to 300. Therefore, the conduction direction of the alternating current of the unit coil 400 is either clockwise or counterclockwise.

The frequency and phase of the alternating current output from the high-frequency alternating current power supply unit 6 to the single coil 400 are the same as the frequency and phase of the alternating current flowing through the coil units 100 to 300. On the other hand, the amplitude of the alternating current flowing through the single coil 400 is 1/8 of the amplitude of the alternating current flowing through the coil units 100 to 300. The amplitude of the alternating current of the single coil 400 is included in the number of loop-shaped coils included in the shortest coil unit in the pitch unit, in the coil unit 300 in the pitch unit (λ ₃ ) in the examples of FIGS. It depends on the number of loop-shaped coils 301-308. The amplitude of the alternating current of the single coil 400 is an amplitude obtained by dividing the amplitude of the alternating current of the coil unit 300 by the number of the loop-shaped coils 301 to 308.

  The area of the coil surface of the single coil 400 is eight times as large as the area of the coil surface of one coil among the loop-shaped coils 301 to 308 included in the coil unit 300.

  Furthermore, the number of turns when the loop of the single coil 400 is formed is equal to the number of turns when the loop shape of the coil unit 300 is formed.

In the above description, the case where three units are stacked in three layers has been described. However, N coil units are stacked in order from a unit having a long pitch unit, and the number of turns (n _N ) of the _Nth coil unit is simply The case where the number of turns (n _s ) of one coil is different will be described.

The amplitude of the alternating current in the N-th coil unit and I _N, and the amplitude I _s of the unit coil 400. Moreover, the area of the coil surface of one coil among the loop-shaped coils included in the Nth coil unit is S _N, and the area of the coil surface of the single coil 400 is S _s . The following formula (2) is established between the number of turns, the amplitude of the alternating current, and the area.

  Next, the synthesized magnetic field in the z-axis direction generated in the power transmission coil 10 will be described with reference to FIG. The winding of the single coil 400 and the winding of the coil unit 300 are the same. The area of the coil surface of the single coil 40 is eight times the area of one of the loop-shaped coils 301 to 308, but the amplitude of the alternating current of the single coil 40 is that of the coil unit 300. It is 1/8 of the amplitude of the alternating current. Furthermore, when the current is conducted, the conduction direction of the single coil 40 is opposite to the conduction direction of the loop-shaped coils 302, 304, 306, and 308.

  Therefore, the magnetic field generated from the single coil 400 acts so as to cancel the magnetic fields generated from the loop coils 302, 304, 306, and 308, respectively. In the area of the loop-shaped coil 308 (corresponding to the area H in FIGS. 8 and 9), the magnetic field generated from the coil units 100 to 300 is directed in the negative direction of the z-axis when the alternating current is conducted.

  In this example, the magnetic field generated from the single coil 400 is directed in the positive direction of the z-axis within the area of the loop-shaped coil 308. Therefore, the magnetic field of the coil unit 300 among the magnetic fields generated from the coil units 100 to 300 is canceled.

  Furthermore, the magnetic field generated from the single coil 400 is the same as the magnetic field generated from the loop coils 301, 303, 305, and 307 in the positive direction of the z axis, and the magnitude of the magnetic field is also the same. Therefore, the single coil 400 can generate a magnetomotive force that strengthens the magnetic field of the loop-shaped coils 301, 303, 305, and 307.

  As a result, this example increases the strength of the near magnetic field in a desired region while preventing a magnetic field (far field) that generates noise at a point sufficiently away from the position where the power transmission coil 10 is installed. be able to.

As described above, in this example, when the power transmission coil 10 is configured by the coil unit up to the Nth (where N is a natural number) and the single coil 400 in order from the unit having the long pitch unit, the Nth coil unit The winding (n _N ), amplitude (I _N ), area (S _N ), single coil 400 winding (n _s ), amplitude (I _s ), area (S _s ) are expressed by the above equation (2). ). As a result, it is possible to increase the strength of the near magnetic field in a desired region while preventing a far magnetic field that causes noise outside the system.

In addition to the primary magnetic field generated by the power transmission coil 10 on the power transmission side (ground side), there is also a secondary magnetic field generated by the power reception coil 20 on the power reception side (vehicle side). . And the synthetic magnetic field which synthesize | combined these magnetic fields is observed outside. As shown in FIG. 2, the length of the power receiving coil 20 in the x direction is approximately the same as half the pitch unit (λ _N ) of the Nth coil unit, and among the magnetic fields generated from the Nth coil unit, the loop The magnetic field of one coil can be almost canceled by the magnetic field of the power receiving coil 20. At this time, the power receiving coil 20 can generate a magnetic field having substantially the same strength and opposite phase as the magnetic field of one loop-shaped coil on the power transmission side by setting the impedance to an appropriate value. However, in this method, the magnetic field of the loop-shaped coil on the power transmission side that does not face the coil surface of the power receiving coil 20 cannot be canceled by the magnetic field generated by the power receiving coil 20 and remains.

  On the other hand, in this example, the single coil 400 generates a magnetic field having an opposite phase to the magnetic field that causes the far magnetic field at a portion that does not face the coil surface of the power receiving coil 20. Therefore, this example can cancel the magnetic field that causes the generation of the far magnetic field, and can prevent the generation of the far magnetic field.

<< 5th Embodiment >>
FIG. 25 is a configuration diagram illustrating a main part of a non-contact power feeding system according to another embodiment of the present invention. This example differs from the first embodiment described above in that the power transmission coil 10 is provided with coil units 500 to 700. Other configurations are the same as those of the first embodiment described above, and the descriptions of the first to fourth embodiments are incorporated as appropriate. In FIG. 25, the positions of the coil units 100 to 300 and the coil units 510 to 530 are shifted in order to make the configurations of the coil units 100, 200, 300 and the coil units 510, 520, and 530 easier to understand. However, in the actual power transmission coil 10, when viewed from the z direction, the coil units 100 to 300, 510 to 530 are arranged so that the outer circumferences of the coil units 100 to 300 overlap and the outer circumferences of the coil units 510 to 530 overlap. Is arranged.

  As illustrated in FIG. 25, the power transmission coil 10 includes coil units 100 to 300 and coil units 510 to 530. The coil unit 510, the coil unit 520, and the coil unit 530 have the same shape as the coil unit 100, the coil unit 200, and the coil unit 300, respectively. The coil units 100 to 300 are overlapped in the z direction to form one coil unit group. Further, the coil units 510 to 530 are overlapped in the z direction to form one coil unit group. That is, the power transmission coil 4 has a plurality of groups in which a plurality of coil units are stacked.

  The high-frequency AC power supply unit 6 is connected to the coil units 100 to 300 and the coil units 510 to 530, respectively.

  FIG. 26 is a plan view of each coil unit in which the overlapping coil units 100 to 300 and the overlapping coil units 510 to 530 are separated from each other. 26A is a plan view of the coil units 100 and 510, FIG. 26B is a plan view of the coil units 200 and 520, and FIG. 26C is a plan view of the coil units 300 and 530. . In FIGS. 26A to 26C, the high-frequency AC power supply unit 6 and the capacitor 11 are connected to each unit. However, the high-frequency AC power supply unit 6 may be a single common power supply. The capacitor 11 may be a common circuit element. In FIG. 26, the arrow shown in the loop-shaped coil represents the direction of current.

  As shown in FIG. 26A, in the xy plane, the coil unit 100 and the coil unit 510 are arranged adjacent to each other with the conductive wires along the longitudinal direction facing each other. Among the conducting wires that form the outer peripheries of the coil unit 100 and the coil unit 510, the conducting wires along the longitudinal direction are parallel.

  The coil unit 510 has loop-shaped coils 511 and 512. On the xy plane, the loop-shaped coil 511 and the coil 512 are arranged adjacent to the loop-shaped coil 101 and the coil 102 of the coil unit 100, respectively. Moreover, when it sees in ay direction, the conducting wire which follows ay direction among the conducting wires which form the outer periphery of the coil unit 100 and the coil unit 510 is arrange | positioned on the same line.

  As shown in FIGS. 26B and 26C, in the xy plane, the set of the coil unit 200 and the coil unit 520 and the set of the coil unit 300 and the coil unit 530 are the coil unit 100 and the coil unit 510. Similarly to the pair, they are arranged next to each other with the conductors along the longitudinal direction facing each other. Further, the loop-shaped coils 521 to 522 included in the coil unit 520 are arranged adjacent to the loop-shaped coils 201 to 204, respectively. The loop-shaped coils 531 to 538 included in the coil unit 530 are arranged adjacent to the loop-shaped coils 301 to 308, respectively.

  That is, the power transmission coil 10 arranges coil units having the same pitch unit among the coil units 100 to 300 and the coil units 510 to 530 included in each group so as to be adjacent to each other on the xy plane. .

  Of the both ends of the coil unit 100 and the coil unit 510, one end of each is connected to the high-frequency AC power supply unit 6 via a wire, and the other end is connected to each other via a wire.

  As for the connection between the coil unit 100 and the coil unit 510, when an alternating current is conducted to the coil units 100 and 510, the loop-shaped coils adjacent to each other in the y direction have the current conduction direction opposite. The coil unit 100 and the coil unit 510 are connected to each other. For example, when the conduction direction of the loop-shaped coil 101 is clockwise, the conduction direction of the adjacent loop-shaped coils 511 is counterclockwise.

  The connection between both ends of the coil unit 200 and the coil unit 520 is the same as the connection between both ends of the coil unit 100 and the coil unit 510. Further, the connection at both ends of the coil unit 300 and the coil unit 530 is the same as the connection at both ends of the coil unit 100 and the coil unit 510.

  When a certain voltage is applied to the power transmission coil 4 from the high-frequency AC power supply unit 6, an AC current flows through each of the coil units 100 to 300 and 510 to 530. Around the loop-shaped coil 101 that conducts current in the clockwise direction, loop-shaped coils 102 and 511 that conduct current in the counterclockwise direction are arranged, respectively. Therefore, in addition to the magnetic field of the coil 102, the magnetic field of the coil 511 also acts to cancel the far magnetic field with respect to the far magnetic field generated by conduction of current to the coil 101. Such cancellation of the far magnetic field is not limited to the coil 101 but also occurs in other coils in the same manner, and also occurs in other coil units 200, 300, 520, and 530. Thereby, this example can suppress a far magnetic field.

  As described above, in this example, the power transmission coil 10 is configured by a plurality of groups of coil units including a plurality of coil knits 100 to 300 and 510 to 530, and coil units having the same pitch unit are arranged in the y direction. Next to each other. And the loop-shaped coil arrange | positioned adjacent to ay direction makes the directions at the time of conduction | electrical_connection of an alternating current into a mutually reverse direction. As a result, not only in the x direction but also in the y direction, the magnetic poles of the magnetic field generated from the loop-shaped coil are opposite to each other, so that a far magnetic field can be suppressed.

<< 6th Embodiment >>
A non-contact power feeding system according to another embodiment of the present invention will be described. FIG. 27 is a plan view of the power transmission coil 10 in the non-contact power feeding system according to the embodiment of the present invention. For configurations other than the power transmission coil 10, the description of the first embodiment is incorporated as appropriate. In FIG. 27, in order to explain the configuration of the power transmission coil 10 in an easy-to-understand manner, the configuration of the power transmission coil 10 is illustrated after being divided into FIGS. 27 (a) and 27 (b). In the actual power transmission coil 10, the first coil portion 610 shown in FIG. 27A and the second coil portion 620 shown in FIG. 27B are overlapped in the z direction. In addition, the equation shown in FIG. 27 represents an alternating current that flows from the alternating current alternating current power supply unit 6 to each coil. However, (omega) shows an angular frequency and t shows time.

The power transmission coil 10 is provided on the traveling road surface so that the coil surface is parallel to the xy plane. In addition, the power transmission coil 10 includes a coil unit 600 in which conductive wires are formed in a wave shape on the xy plane in accordance with a pitch unit (λ ₁ ) along the x direction. The coil unit 600 has a first coil part 610 and a second coil part 620.

As shown in FIG. 27A, the first coil portion 610 has a wave-like conducting wires 611 to 613 having a pitch unit (λ ₁ ) as one cycle, and a connecting portion 614 for connecting the conducting wires 611 to 613. doing.

  The wavy conducting wires 611 to 613 are configured by bending one conducting wire into a rectangular wave shape. One conductor may be a single wire or a plurality of stranded wires. Of the conducting wires 611 to 613, the coil shape for one period is the same.

The conducting wire 611 is formed of a rectangular wave for one cycle from a predetermined position in the x direction (corresponding to the dotted line P in FIG. 27A) toward the positive direction of the x axis (toward the traveling direction of the vehicle). Has been. The conductor 612 is in the positive direction of the x-axis for a given position in the x-direction (the dotted line P), from lambda _1/6 shifted by position toward the positive direction of x-axis in a rectangular wave of 1 cycle Is formed. Further, conductor 613, in the positive direction of the x-axis for a given position in the x-direction (the dotted line P), lambda _1/3 by shifting the position, rectangular wave of 1 cycle towards the positive direction of the x-axis It is formed with. The rectangular waves of the conducting wires 611 to 613 have the same shape. Each rectangular wave is point-symmetric about a point corresponding to a half-cycle position.

  The connection portion 614 is an end portion in the x direction of the first coil portion 610 and is a wiring for connecting one end of the conducting wires 611 to 613. The connecting portion 614 is provided at the end opposite to the end connected to the high-frequency AC power source 6 among the ends of the conducting wires 611 to 613. The connection portion 614 is also a portion that becomes zero in the total sum of currents flowing through the conducting wires 611 to 613 (however, one direction of current conduction is positive or negative).

As shown in FIG. 27B, the second coil unit 620 includes a wave-like conductors 621 to 623 each having a pitch unit (λ ₁ ) as one cycle, and a wiring part 624 for connecting the conductors 621 to 623. doing. The wavy lead wires 621 to 623 have the same shape as the wavy lead wires 611 to 613.

The conducting wire 621 is formed of a rectangular wave for one period from a predetermined position in the x direction (corresponding to the dotted line Q in FIG. 27B) toward the positive direction of the x axis. Conductor 622 is in the negative direction of the x-axis for a given position in the x-direction (the dotted line Q), from lambda _1/6 position shifted toward the positive direction of the x-axis is formed by a rectangular wave of 1 cycle ing. Conductor 613 is in the positive direction of the x-axis for a given position in the x-direction (the dotted line Q), from lambda _1/3 position shifted toward the positive direction of the x-axis is formed by a rectangular wave of 1 cycle ing.

That is, the first coil portion 610, the displacement amount in the x-direction as lambda _1/6, are staggered each conductors 612 and 613 in the positive direction of the x-axis relative to the wave conductor 611. On the other hand, the second coil portion 620, the displacement amount in the x direction lambda _1/6, are staggered in the negative direction of the conductors 622, 623 respectively the x-axis relative to the wave conductor 621.

  The wiring part 624 is a wiring for connecting one end of the conducting wires 621 to 623.

The high-frequency AC power supply unit 6 (see FIG. 1) outputs three-phase AC currents having different phases to the first coil unit 610 and the second coil unit 620, respectively. The AC currents flowing from the high-frequency AC power supply unit 6 to the conducting wires 611 to 613 of the first coil unit 610 have the same amplitude (I) and the same angular frequency (ω _1a ). The phase of the alternating current flowing through the conducting wire 612 is advanced by π / 3 with respect to the phase of the alternating current flowing through the conducting wire 611. Further, the phase of the alternating current flowing through the conducting wire 613 is advanced by 2π / 3 with respect to the phase of the alternating current flowing through the conducting wire 611. Note that “t” in FIG. 27 represents time.

The AC currents flowing from the high-frequency AC power supply unit 6 to the conducting wires 621 to 623 of the second coil unit 620 have the same amplitude (I) and the same angular frequency (ω _1b ). The phase of the alternating current flowing through the conducting wire 622 is delayed by π / 3 with respect to the phase of the alternating current flowing through the conducting wire 621. Further, the phase of the alternating current flowing through the conducting wire 623 is delayed by 2π / 3 with respect to the phase of the alternating current flowing through the conducting wire 621.

  Here, the shift | offset | difference amount of conducting wire 611-613, 621-623 and the phase of the alternating current which flows into each conducting wire 611-613, 621-623 are demonstrated.

The amount of deviation of the wavy conductive wire in the x direction is determined by the number of phases formed by the plurality of wavy conductive wires 611 to 613 of the first coil portion 610. In the example of FIG. 27, the conductive wires 611 to 613 are arranged so as to form three phases when an alternating current is passed through the first coil unit 610. At this time, the unit of the deviation amount is the length obtained by dividing the number of phases with respect to the half length of the pitch unit (λ ₁ ). In the example of FIG. 27, the _{λ 1/2 × 1/3} , the unit of the shift amount is λ _1/6. Then, so as to form a three-phase, the deviation amount is lambda _1/6 next between the conductor 611 and the conductor 612, the deviation amount between the conductor 612 and the conductor 613 becomes λ _1/6.

For example, when the first coil unit 610 is an N-phase coil, N wave-shaped coils are arranged in a pitch unit (λ ₁ ) portion, and the shift amount of each wave-shaped coil is set to λ ₁ / 2 × 1 / N. The shift amount of the second coil unit 620 is also the same as that of the first coil unit 610.

  Each phase of the alternating current that flows through the conducting wires 611 to 613 is determined by the shape of the coil connected by the connection portion 614. For example, in FIG. 27A, when the current in the positive direction of the x-axis flows only in the wavy conductive wire 611, the current is branched at the connection portion 614, and the current in the x-axis is connected at the conductive wires 612 and 613. Flows in the negative direction. At this time, in order to make the current flowing through the conducting wires 611 to 613 a three-phase alternating current, a phase difference must be given by the alternating current of each phase according to the position where the current returns at the connecting portion 614.

In the example of FIG. 27A, when viewed in the x direction, the connection point between the conducting wire 611 and the connection portion 614 corresponds to one cycle. Further, the connection point between the conducting wire 612 and the connecting portion 614 and the connecting point between the conducting wire 613 and the connecting portion 614 correspond to one cycle. Then, during each connection point of the connecting portion 614 and the conductor 611 to 613 are shifted by the length of λ _1/6. Therefore, the phase of the alternating current of the conducting wire 612 is π / π relative to the phase of the alternating current of the conducting wire 611 so that a three-phase alternating current flows through the conducting wires 611 to 613 while corresponding to the deviation between the connection points. 3 has advanced. Further, the phase of the alternating current of the conducting wire 613 is further advanced by π / 3 with respect to the phase of the conducting wire 612, and therefore the phase of the conducting wire 611 is advanced by 2π / 3.

  That is, the phase of each alternating current flowing through the conducting wires 611 to 613 corresponds to the shift amount of the conducting wires 611 to 613. When an alternating current having a certain phase is supplied to the reference conducting wire 611, the larger the deviation between the conducting wire 611 and the conducting wires 612 and 613, the greater the alternating current of the conducting wire 611 and the alternating current of the conducting wires 612 and 613. The phase between is increased. In the example of FIG. 27A, the amount of deviation between the wavy coils is larger in the amount of deviation between the conductors 611 and 613 than the amount of deviation between the conductors 611 and 612. Therefore, the phase of the alternating current of conducting wire 613 is larger than the phase of the alternating current of conducting wire 612.

  Next, the magnetic field characteristics of the first coil unit 610, the magnetic field characteristics of the second coil unit 620, and the combined magnetic field characteristics of the power transmission coil 10 will be described with reference to FIG. FIG. 28 is a graph showing the characteristics of each magnetic field. The vertical axis indicates the intensity of the magnetic field component in the z direction, and the horizontal axis indicates the position in the x direction. Graph a shows the magnetic field characteristics of the first coil unit 610, graph b shows the magnetic field characteristics of the second coil unit 620, and graph c shows the magnetic field characteristics of the power transmission coil 10. Moreover, the arrow of FIG. 28 represents the direction of the phase velocity.

ただし、ｋ_１は波数であり、ｋ_１＝２π／λ_１で表される。 The magnetic field generated from the first coil unit 610 is a sinusoidal traveling wave that travels in the positive direction of the x-axis. On the other hand, the magnetic field generated from the second coil unit 620 is a sinusoidal backward wave that travels in the negative direction of the x-axis. In this case, the phase velocity of the traveling wave _{(v 1a)} and the phase velocity of the backward wave _{(v 1b)} is represented by the following respective equations (3).

However, _{k 1} is the wave number _is expressed by _{k 1} = _2π / _λ 1.

The general formula of the traveling wave (Bz _1a ) and the backward wave (Bz _1b ) of the magnetic field is as shown in the following formula (4).

  The magnetic field in the z direction of the power transmission coil 10 is a magnetic field obtained by synthesizing a magnetic field represented by a traveling wave and a magnetic field represented by a backward wave. In this example, as shown in FIG. 28, the peak portion of the traveling wave and the peak portion of the backward wave move in the x direction in opposite directions. Therefore, the magnetic field in the z direction can be strengthened at the portion where the peak portion of the traveling wave and the peak portion of the backward wave overlap. Further, if the phase velocity of the traveling wave and the backward wave are set to different velocities, the position of the peak portion in the x direction can be moved. Hereinafter, description will be made using a general formula of the synthesized wave.

The general formula of the magnetic field in the z direction of the power transmission coil 10 is obtained by summing the two formulas of formula (4) using the product-sum formula of trigonometric functions, and is expressed as the following formula (5). The

  In equation (5), the cosine component is a moving component, and the sine component is a vibration component.

From the equation (5), the phase velocity (velocity in the x direction) (v _z ) of the magnetic field of the power transmission coil 10 is represented by the following equation (6).

That is, the controller 8 (see FIG. 1) adjusts the phase velocity (V _z ) to the vehicle speed of the vehicle traveling on the power feeding path, so that the peak portion of the magnetic field of the power transmission coil 10 shown in the graph c of FIG. Can be made to follow the power receiving coil 20. Therefore, the controller 8 controls the frequency (ω _1a , ω _1b ) of the alternating current that flows through the first coil unit 610 and the second coil unit 620 according to the vehicle speed of the vehicle.

The controller 8 controls the drive frequency of the high-frequency AC power supply unit 6 in order to control the frequency (ω _1a , ω _1b ) of the alternating current. At this time, the vibration component of Expression (5) must correspond to the resonance frequency of the power transmission circuit unit 1 and the resonance frequency of the power reception circuit unit 2 in order not to reduce the magnetic action between the power transmission coil 10 and the power reception coil 20. I must. In order to make the resonance frequency correspond to the vibration component of the magnetic field of the power transmission coil 10 when the resonance frequency is f ₀ , the following equation (7) must be satisfied.

Therefore, the vibration frequency of the combined magnetic field ((ω _1a + ω _1b ) / 2), the resonance frequency of the resonance circuit, and the drive frequency of the high-frequency AC power supply unit 6 are made to correspond so that the magnetic resonance between the coils can be maintained. However, it is a condition that the phase speed of the combined magnetic field matches the vehicle speed. In order to satisfy such a condition, the frequency (ω _1a , ω _1b ) of the alternating current is set by the controller 8 under the conditions shown in the following equations (8) and (9). Expressions (8) and (9) are derived from the simultaneous equations of Expressions (6) and (7). However, the phase velocity (v _z ) matches the vehicle speed.

Among the expressions (8) and (9), the resonance frequency (f ₀ ) is determined by the circuit design of the transmission circuit unit 1, and the wave number (k ₁ ) is a pitch unit of the first coil unit 610 and the second coil unit 620. And is predetermined by the coil shape. Therefore, a map indicating the correspondence between the vehicle speed of the vehicle and the angular frequencies (ω _1a , ω _1b ) is recorded in advance in a memory (not shown) of the controller 8 so as to satisfy the expressions (8) and (9). Keep it.

  Then, the controller 8 calculates the vehicle speed from the vehicle position and detection time information by a sensor or the like that detects the vehicle position. Alternatively, the controller 8 may detect the position and vehicle speed of the vehicle by receiving a signal from the vehicle.

The controller 8 refers to the map and identifies angular frequencies (ω _1a , ω _1b ) corresponding to the detected or calculated vehicle speed. Then, the controller 8 sets the drive frequency of the power supply portion that outputs current to the first coil unit 610 in the high-frequency AC power supply unit 6 to ω _1a and outputs current to the second coil unit 620. The drive frequency of the power supply part to be set is set to ω _1b . Thereby, the controller 8 controls the frequency of the alternating current that flows through the first coil unit 610 and the frequency of the alternating current that flows through the second coil unit 620 according to the vehicle speed of the vehicle traveling on the power feeding path.

As described above, in this example, a coil unit having a conductive wire in the xy plane is formed in accordance with the pitch unit (λ ₁ ) along the x direction, and the pitch unit (λ ₁ ) is set as a period in the coil unit. A plurality of wavy conductive wires 611 to 613 and wavy coils 621 to 623 each having a pitch unit (λ ₁ ) as a cycle are provided. The present example, an undulating wire 611 to 613, the deviation amount (λ _1/6) min, shifted in the positive direction of the x-axis is arranged, an undulating coil 621 to 623, the deviation amount (lambda _1/6 ) And is shifted in the negative direction of the x-axis. Further, the present embodiment, the controller 8, the deviation amount of the conductor 611 to 613 of the current phase of the coil portion 610 (λ _1/6) and in correspondence, the amount of deviation of the coil 621 to 623 of the current phase of the second coil portion 620 (λ _1/6) and is associated, to control the frequency of the alternating current applied to the frequency and the second coil portion 620 of the alternating current applied to the coil 610 in accordance with the position of the vehicle.

  Thereby, this example can raise the intensity | strength of the near magnetic field in a specific part, and can reduce the near magnetic field intensity in another unnecessary part so that a vehicle may follow.

  Further, in this example, when an alternating current is passed, the coil portion 610 is formed so that a magnetic field in the z direction is formed by a traveling wave directed in the positive direction of the x axis, and the magnetic field in the z direction is negative of the x axis. The second coil part 620 is formed so as to be formed by a backward wave directed in the direction. Thereby, this example can obtain the magnetic field synthetic wave which can be fed while moving with the vehicle.

  As a modification of the present invention, the first coil unit 610 and the second coil unit 620 may be configured as shown in FIG. FIG. 29 is a plan view of a coil unit 600 of a non-contact power feeding system according to a modification of the present invention. 29, as in FIG. 27, the first coil portion 610 and the second coil portion 620 that originally overlap in the z direction are separated and shown in FIGS. 29 (a) and 29 (b). .

The first coil part 610 according to the modification does not have the connection part 614 shown in FIG. The first coil unit 610 has wave-like conducting wires 615 to 617 with a pitch unit (λ ₁ ) as one cycle. The wavy portions of the conductive wires 615 to 617 are the same as the wavy conductive wires 611 to 613.

The conducting wire 615 is formed of a rectangular wave for one period from a predetermined position in the x direction (corresponding to the dotted line P in FIG. 29A) toward the positive direction of the x axis. Conductor 616 is in the positive direction of the x-axis for a given position in the x-direction (the dotted line P), from lambda _1/6 position shifted toward the positive direction of the x-axis is formed by a rectangular wave of 1 cycle ing. Also, conductors 616, on which is inverted relative to the square wave conductor 615, are staggered lambda _1/6 with respect to the dotted line P. In the positive direction of the x-axis relative to the conductor 617 a predetermined position in the x-direction (the dotted line P), from lambda _1/3 position shifted, it is formed by a rectangular wave of 1 cycle towards the positive direction of the x-axis Yes.

Of the both ends of the conducting wires 615 to 617, the end opposite to the high-frequency AC power supply 6 is connected at the same position (neutral point 618) in the x direction. Therefore, conductor 615, from one period (corresponding to pitch unit lambda ₁₎ minute position to the neutral point 618, lambda _1/6 min, and extend the lead into the positive direction of the x-axis. Lead 617, to align the ends to the neutral point 618, in the form of a square wave and 5 [lambda] _1/6 min.

As shown in FIG. 29B, the second coil section 620 has wavy conductive wires 625 to 627 each having a pitch unit (λ ₁ ) as one cycle.

The conducting wire 625 is formed of a rectangular wave for one period from a predetermined position in the x direction (corresponding to the dotted line Q in FIG. 29B) toward the positive direction of the x axis. Conductor 626 is a position shifted lambda _1/6 in the negative direction of the x-axis, is formed by a rectangular wave of 1 cycle towards the positive direction of the x-axis relative to the dotted line Q. Also, conductors 626, on which is inverted relative to the square wave conductor 625, are staggered lambda _1/6 with respect to the dotted line Q. Conductor 627 is a position shifted lambda _1/3 in the negative direction of the x-axis, is formed by a rectangular wave of 1 cycle towards the positive direction of the x-axis relative to the dotted line Q.

Of the both ends of the conducting wires 615 to 617, the end opposite to the high-frequency AC power supply unit 6 is connected at a neutral point 628. Lead 625, to align the ends to the neutral point 618, in the form of a square wave with 5 [lambda] _1/6 min. Conductor 627 from one period (corresponding to pitch unit lambda ₁₎ minute position to the neutral point 618, lambda _1/6 min, and extend the lead into the positive direction of the x-axis.

  Next, the phase of the alternating current flowing through the conducting wires 615 to 617 and the conducting wires 625 to 627 will be described. In the coil unit 600 according to the modification, the conducting wires 615 to 617 and the conducting wires 625 to 627 are connected at neutral points 618 and 628, respectively. Therefore, the phase difference due to the shift of the connection point of the coil end portion may not be applied to the phase of the alternating current of each of the conductive wires 615 to 617 and 625 to 627.

  On the other hand, since the alternating current flowing through the conducting wires 615 to 617 and the conducting wires 625 to 627 is a three-phase alternating current, the phase difference for making the three-phase alternating current is attached to the phase of the alternating current of the conducting wires 615 to 617 and 625 to 627. It is done. That is, the phase of the alternating current of the conducting wire 616 is advanced by 4π / 3 with respect to the phase of the alternating current of the conducting wire 615. Further, the phase of the alternating current of the conducting wire 617 is advanced by 2π / 3 with respect to the phase of the conducting wire 615. Further, the phase of the alternating current of the conducting wire 626 is delayed by 4π / 3 with respect to the phase of the alternating current of the conducting wire 625. Further, the phase of the alternating current of the conducting wire 627 is delayed by 2π / 3 with respect to the phase of the conducting wire 625.

Phase difference between the current phase of the current phase and conductor 616 of the conductor 615 for (4 [pi] / 3), lead 616, after inverting the square wave conductors 615, a position deviation amount was lambda _1/6 Is arranged. A rectangular wave when moving parallel to the x-direction, the deviation amount between the conductors 615 and 616 becomes 2 [lambda] _1/3. Therefore, the phase difference between the conductor 615 and the conductor 616 are set corresponding to the displacement amount (2λ _1/3). For even the phase difference between the conductor 625 and the conductor 626, likewise, it is set corresponding to the displacement amount (2λ _1/3).

  That is, the phase of each alternating current flowing through the conducting wires 615 to 617 corresponds to the amount of deviation of the conducting wires 615 to 617. When an alternating current having a certain phase is supplied to the reference conducting wire 615, the larger the deviation between the conducting wire 615 and the conducting wires 616, 617, the larger the alternating current of the conducting wire 615 and the alternating current of the conducting wires 616,617. The phase between is increased. Moreover, the relationship between the phase difference of the conducting wires 625 to 627 and the shift amount of the conducting wires 625 to 627 is the same as the relationship of the conducting wires 625 to 627 described above.

In this example, the first coil unit 610 and the second coil unit 620 have one rectangular wave having a period of the pitch unit (λ ₁ ). However, a plurality of rectangular waves are used to form a plurality of rectangular wave coils. You may arrange along an x-axis. Moreover, the shape of conducting wire 611-613, 615-617, 621-623, 625-627 does not necessarily need to be a rectangular wave, For example, other shapes, such as a sine wave, may be sufficient.

<< 7th Embodiment >>
FIG. 30 is a conceptual diagram for explaining a power transmission coil 10 in a non-contact power feeding system according to another embodiment of the invention. This example is different from the above-described sixth embodiment in that a plurality of coil units are provided in the power transmission coil 10. The other configuration is the same as that of the sixth embodiment described above, and the description of the sixth embodiment is incorporated as appropriate.

  The power transmission coil 10 includes a coil unit 700 and a coil unit 800 in addition to the coil unit 600 according to the sixth embodiment. The coil unit 700 has a first coil part 710 and a second coil part 720, and the coil unit 800 has a second coil part 810 and a second coil part 820.

The first coil portion 710, while a pitch unit and lambda _2, a coil for forming a magnetic field in the z-direction in the traveling wave. The second coil unit 720, while the pitch unit and lambda _2, a coil for forming a magnetic field in the z direction backward wave. The first coil portion 810, while a pitch units lambda _3, a coil for forming a magnetic field in the z-direction in the traveling wave. The second coil unit 820, while a pitch units lambda _3, a coil for forming a magnetic field in the z direction backward wave.

  Next, the overlapping of the coils will be described with reference to FIG. 30A shows a plan view of the coil portions 610, 620, 710, 720, 810, and 820, FIG. 30B shows a plan view of the coil units 600 to 800, and FIG. 30C shows a power transmission coil. FIG. 10 is a plan view. In FIG. 30A, the outer shape of the coil portion is smaller than that of the coil units 600 to 800, but the actual size is the same.

  As shown in FIGS. 30A and 30B, the first coil unit 610 and the second coil unit 620 are overlapped in the z direction to constitute the coil unit 600. Moreover, the coil unit 700 is comprised by the 1st coil part 710 and the 2nd coil part 720 overlapping in az direction. The first coil unit 810 and the second coil unit 820 overlap each other in the z direction, so that the coil unit 800 is configured.

  As illustrated in FIG. 30B and FIG. 30C, the power transmission coil 10 is configured by the coil units 600 to 800 overlapping in the z direction.

  Next, each structure of the coil units 600-800 is demonstrated. Since the coil unit 600 is the same as that of the sixth embodiment, the description thereof is omitted. 31 is a plan view of the coil unit 700, FIG. 31 (a) is a plan view of the first coil portion 710, and FIG. 31 (b) is a plan view of the second coil portion 720. FIG. 32 is a plan view of the coil unit 800, FIG. 32 (a) is a plan view of the first coil portion 810, and FIG. 32 (b) is a plan view of the second coil portion 820.

As shown in FIG. 31A, the first coil portion 710 has wave-like conducting wires 711 to 713 having a pitch unit (λ ₂ ) as one cycle, and a connecting portion 714 for connecting the conducting wires 711 to 713. doing. The shape of the conducting wires 711 to 713 is rectangular wave like the conducting wires 611 to 613, but the pitch unit (λ ₂ ) is shorter than the pitch unit (λ ₁ ). Therefore, each of the conductive wires 711 to 713 includes two rectangular waves per coil unit, and the number of rectangular waves included in the coil unit 700 is larger than that of the coil unit 600.

As shown in FIG. 31 (b), the second coil portion 720 has wavy conductive wires 721 to 723 each having a pitch unit (λ ₂ ) as one cycle, and a connection portion 724 for connecting the conductive wires 721 to 723. doing. The conductors 721 to 723 have a rectangular wave shape like the coils 621 to 623, but the pitch unit (λ ₂ ) is shorter than the pitch unit (λ ₁ ). Similarly to the first coil unit 710, the number of rectangular wave coils included in the second coil unit 720 is larger than that of the coil unit 600.

As shown in FIG. 32 (a), the first coil portion 810 has a wavy conductive wire 811-813 having a pitch unit (λ ₃ ) as one cycle, and a connecting portion 814 for connecting the conductive wires 811-813. doing. The shape of the conducting wires 811 to 813 is a rectangular wave like the conducting wires 611 to 613, but the pitch unit (λ ₃ ) is shorter than the pitch unit (λ ₁ ) and the pitch unit (λ ₂ ). Therefore, each of the conductive wires 811 to 813 includes four rectangular waves per coil unit, and the number of rectangular waves included in the coil unit 800 is larger than that of the coil units 600 and 700.

As shown in FIG. 32 (b), the second coil portion 820 has wavy lead wires 821 to 823 having a pitch unit (λ ₃ ) as one cycle and a connection portion 824 for connecting the lead wires 821 to 823. doing. The conductors 821 to 823 have a rectangular wave shape like the coils 621 to 623, but the pitch unit (λ ₃ ) is shorter than the pitch unit (λ ₁ ) and the pitch unit (λ ₂ ). Similarly to the first coil unit 810, the number of rectangular wave coils included in the second coil unit 820 is larger than that of the coil units 600 and 700.

  The phase of the alternating current flowing through the conducting wires 712 and 713 is advanced by π / 3 and 2π / 3, respectively, with respect to the phase of the alternating current flowing through the conducting wire 711 serving as the reference, similarly to the phases of the conducting wires 612 and 613. Further, the phase of the alternating current flowing through the conducting wires 722 and 723 is delayed by π / 3 and 2π / 3 respectively with respect to the phase of the alternating current flowing through the conducting wire 721 serving as the reference, similarly to the phases of the coils 622 and 623. .

  Similarly, the phase of the alternating current flowing through the conducting wires 812 and 813 is also advanced by π / 3 and 2π / 3 with respect to the phase of the alternating current flowing through the conducting wire 811 serving as a reference. Similarly, the phase of the alternating current flowing through the conducting wires 822 and 823 is also delayed by π / 3 and 2π / 3 from the phase of the alternating current flowing through the reference conducting wire 821.

The high-frequency AC power supply unit 6 supplies a three-phase AC current having an angular frequency (ω _1a ) to the first coil unit 610 and a three-phase AC current having an angular frequency (ω _1b ) to the second coil unit 620. . In addition, the high-frequency AC power supply unit 6 supplies a three-phase AC current having an angular frequency (ω _2a ) to the first coil unit 710 and a three-phase AC current having an angular frequency (ω _2b ) to the second coil unit 720. Shed. The high-frequency AC power supply unit 6 supplies a three-phase AC current having an angular frequency (ω _3a ) to the first coil unit 810 and a three-phase AC current having an angular frequency (ω _3b ) to the second coil unit 820. .

  Next, the characteristics of the magnetic field generated from the coil unit 700 and the characteristics of the magnetic field generated from the coil unit 800 will be described with reference to FIGS. 33 and 34. FIG. 33 is a graph showing the magnetic field characteristics of the coil unit 700, and FIG. 34 is a graph showing the magnetic field characteristics of the coil unit 800. The vertical axis indicates the intensity of the magnetic field component in the z direction, and the horizontal axis indicates the position in the x direction. Graph a shows the magnetic field characteristics of the first coil units 710 and 810, graph b shows the magnetic field characteristics of the second coil units 720 and 820, and graph c shows the combined magnetic field characteristics of the coil units 700 and 800, respectively. Indicates. Moreover, the arrows in FIGS. 33 and 34 indicate the direction of the phase velocity.

  Similar to the first coil unit 610 and the second coil unit 620 of the coil unit 600, the magnetic field generated from the first coil unit 710 becomes a traveling wave of a sine wave that travels in the positive direction of the x axis, and the second coil. The magnetic field generated from the part 720 becomes a sinusoidal backward wave that travels in the negative direction of the x-axis. Therefore, as shown in FIG. 33, similarly to the coil unit 600, the magnetic field generated from the coil unit 700 is represented by a combined wave of the traveling wave and the backward wave, and the peak part of the traveling wave and the peak part of the backward wave Reinforce each other at the overlap.

From the pitch unit (λ ₂ ) of the first coil unit 710 and the second coil unit 720, the wave number k ₂ is represented by k ₂ = 2π / λ ₂ . Moreover, the synthetic | combination magnetic field to the z direction of the coil unit 700 is represented by Formula (10) by Formula (3)-(5) of 6th Embodiment.

Further, the phase velocity (v _z2 ) is expressed by Expression (11).

  Similar to the coil unit 700 described above, the magnetic field generated from the coil unit 800 is a composite wave of a traveling wave magnetic field generated by the first coil unit 810 and a backward wave magnetic field generated by the second coil unit 820. . As shown in FIG. 34, the magnetic field of the coil unit 800 is represented by a combined wave of a traveling wave and a backward wave, and strengthens at a portion where the peak part of the traveling wave and the peak part of the backward wave overlap.

From the pitch unit (λ ₃ ) of the first coil unit 810 and the second coil unit 820, the wave number k ₃ is expressed by k ₃ = 2π / λ ₃ . Moreover, the synthetic magnetic field to the z direction of the coil unit 800 is represented by Formula (12) by Formula (3)-(5) of 6th Embodiment.

Further, the phase velocity (v _z3 ) is expressed by Expression (13).

  The magnetic field in the z direction of the power transmission coil 10 is a magnetic field obtained by combining the magnetic field in the z direction of the coil unit 600, the magnetic field in the z direction of the coil unit 700, and the magnetic field in the z direction of the coil unit 800. As shown in the graph c in FIGS. 28, 33, and 34, the combined magnetic field of each of the coil units 600 to 800 is represented by a traveling wave of a sine wave. Therefore, if the peak portions of the respective sine waves are aligned at the position in the x direction, the magnetic field of the power transmission coil 100 is strengthened in the z direction.

The combined magnetic fields of the coil units 600 to 800 are represented by phase velocities v _1z , v _2z , and v _3z . If these phase velocities are matched, the peak portions of the sine waves overlap at the same position. .

Furthermore, in order to match the peak portion of the composite magnetic field to the vehicle traveling on the power supply path, all the above phase velocities (v _1z , v _2z , v _3z ) must be matched to the vehicle speed. For this reason, the controller 8 (see FIG. 1) determines the frequencies (ω _1a , ω _1b , ω _2a , ω _2b , ω _3a , ω _3b ) are controlled.

At this time, similarly to the sixth embodiment, the controller 8 adjusts the frequency (ω _1a , ω _1b ,...) _So that the frequency of the alternating current corresponds to the resonance frequency of the power transmission circuit unit 1 and the resonance frequency of the power reception circuit unit 2. ω _2a , ω _2b , ω _3a , ω _3b ).

The frequency (ω _2a , ω _2b , ω _3a , ω _3b ) and the vehicle speed of the vehicle correspond to each other in the same manner as the correspondence relationship between the frequency (ω _1a , ω _1b ) and the vehicle speed. For this reason, the controller 8 records a map indicating the correspondence relationship between the frequency (ω _1a , ω _1b , ω _2a , ω _2b , ω _3a , ω _3b ) and the vehicle speed of the vehicle in the memory, and relates the detected vehicle speed to the vehicle speed. The frequency (ω _1a , ω _1b , ω _2a , ω _2b , ω _3a , ω _3b ) is calculated by referring to the map, and the drive frequency of the high-frequency AC power supply unit 6 is controlled.

FIG. 35 shows the characteristics of the combined magnetic field of the power transmission coil 10 when the phase velocities (v _1z , v _2z , v _3z ) are matched. FIG. 35 is a graph showing the characteristics of the combined magnetic field of the power transmission coil 10. In FIG. 35, a portion A indicates a magnetic field (power receiving magnetic field) received by the power receiving coil 20, and a portion B indicates a leakage magnetic field. According to the graph of FIG. 35, the present invention can reduce the leakage magnetic field to 1/3 or less of the peak magnetic field of the receiving magnetic field.

As described above, in this example, the coil units 600 to 800 having different pitch units (λ ₁ , λ ₂ , λ ₃ ) are arranged so as to overlap in the z direction. Thereby, this example can raise the intensity | strength of the near magnetic field in a specific part, and can reduce the near magnetic field intensity in another unnecessary part so that a vehicle may follow.

  In addition, according to the vehicle speed of the vehicle, the frequency of the alternating current that flows from the high frequency AC power supply unit 6 to the first coil units 610, 710, 810, and the high frequency AC power supply unit 6 to the second coil units 620, 720, Each frequency of the alternating current flowing through 820 is controlled. Thereby, this example can raise the intensity | strength of the near magnetic field in a specific part, and can reduce the near magnetic field intensity in another unnecessary part so that a vehicle may be followed.

In this example, the first coil portions 710 and 810 and the second coil portions 720 and 820 have two and four rectangular waves each having a pitch unit (λ ₂ , λ ₃ ) as a period. The number may be 3 or more and 5 or more, and a plurality of rectangular wave coils may be arranged along the x-axis. Moreover, the coil shape of the pitch unit does not necessarily have to be a rectangular wave, and may be another shape such as a sine wave. Further, the number of coil units 600 to 800 constituting the power transmission coil 10 is not limited to three, and may be four or more. When the number of coil units is N, the controller 8 determines the frequency of the alternating current that flows through the first to Nth first coil sections and the frequency of the alternating current that flows through the first to Nth second coil sections. Will be controlled.

<< Eighth Embodiment >>
FIG. 36 is a plan view of the first coil unit 610 included in the coil unit 600 in the power transmission coil unit 10 of the non-contact power feeding system according to another embodiment of the invention. This example is different from the sixth embodiment described above in that the shapes of the first coil unit 610 and the second coil unit 620 are different from the high-frequency AC power source unit 6 as a single-phase AC power source. The other configuration is the same as that of the sixth embodiment described above, and the description of the sixth or seventh embodiment is incorporated as appropriate. Note that, in FIG. 36, the conductive wires 611 to 613 are slightly shifted in order to make the configuration of the first coil portion 610 easier to understand.

The first coil portion 610 is formed of a single continuous wire from a terminal serving as one end to a terminal serving as the other end. The first coil portion 610 has conducting wires 611-613. The conductive 611 is formed of a rectangular wave for four periods with a pitch unit (λ ₁ ) as a period from a predetermined position in the x direction (corresponding to the dotted line P in FIG. 36). The conducting wire 611 is formed by a straight line extending in the negative direction of the x axis starting from the tip of a rectangular wave for four cycles. end point of the straight line extending in the negative direction of the x-axis, from the position of the dotted line P, a position shifted in the positive direction of the x-axis by lambda _1/6 min.

Conductor 612 from the positive direction to lambda _1/6 min displacement position of the x-axis relative to the position of the dotted line P, and a cycle of pitch unit (lambda _1), and is formed by a rectangular wave of 4 cycles. Further, the conducting wire 612 is formed by a straight line extending in the negative direction of the x-axis starting from the tip of a rectangular wave for four cycles. end point of the straight line extending in the negative x-axis direction from the position of the dotted line P, a position shifted in the positive x-axis direction by lambda _1/3 min.

Conductor 613, from the positive direction to lambda _1/3 min displacement position of the x-axis relative to the position of the dotted line P, and a cycle of pitch unit (lambda _1), and is formed by a rectangular wave of 4 cycles. The conducting wire 613 is formed by a straight line extending in the negative direction of the x-axis starting from the tip of a rectangular wave for four cycles. The end point of the straight line extending in the negative direction of the x-axis is the end of the first coil unit 10.

ただし、第１コイル部６１０は、３つの導線６１１〜６１３で形成されているため、Ｎ＝３となる When the total length of the conducting wire of the first coil portion 610 is L _c and the total length of the conducting wire 611 is L _cp , the relationship of Expression (14) is established between the first coil portion 610 and L _c .

However, since the first coil portion 610 is formed by three conducting wires 611 to 613, N = 3.

Moreover, the x-direction length and L _o of the first coil portion 610, and the length of the y direction of the first coil portion 610 and w, the following equation (15) holds.

However, _{k 1} is the wave _number, and _{k 1} = _2π / _λ 1. The length (L _o ) corresponds to the length in the longitudinal direction of the coil unit 600, and the length (w) corresponds to the length in the width direction of the coil unit 600.

  When the length of the first coil portion 610 in the x direction is sufficiently long and a single-phase alternating current is passed through the first coil portion 610 with the above configuration, the space between the conductor 611, the conductor 612, and the conductor 613 is reduced. Causes a phase difference of 120 °.

  Thus, in this example, even when the high-frequency AC power supply unit 6 is a single-phase power supply, a traveling wave can be formed by the shape of the first coil unit 610.

  Further, the second coil portion 620 can also form a coil with a single continuous wire in the same manner as described above to generate a backward wave magnetic field.

  As described above, in this example, the first coil unit 610 and the second coil unit 620 are each formed by a single continuous wire, and the first coil unit 610 and the second coil unit 620 are formed from the high-frequency AC power supply unit 6. The alternating current that flows through is assumed to be a single-phase alternating current. Thus, a traveling wave magnetic field component and a backward wave magnetic field component can be generated by a single-phase power source. As a result, the cost of the high-frequency AC power supply unit 6 can be suppressed.

  In addition, in this example, although conducting wire 611-613 contains four rectangular waves, it is not restricted to four, Two, three, or five or more may be sufficient. Moreover, the number of the conducting wires 611 to 613 is not limited to three and may be four or more.

DESCRIPTION OF SYMBOLS 1 ... Power transmission circuit part 10 ... Power transmission coil 11 ... Capacitor 2 ... Power receiving circuit part 20 ... Secondary winding 21, 22 ... Capacitor 5 ... Non-contact electric power feeding part 6 ... High frequency alternating current power supply part 100, 121-123, 200, 221- 223, 300, 321-323, 510, 520, 530, 600, 700, 800 ... Coil unit 400 ... Single coil 610, 710, 810 ... First coil part 620, 720, 820 ... Second coil part

Claims (14)

In a non-contact power feeding device that supplies power in a non-contact manner by at least a magnetic action to a power receiving coil provided in a moving body that travels in a predetermined direction,
A power transmission coil that is electrically connected to a power source and transmits power in a contactless manner to the power reception coil;
Current control means for controlling a current output from the power source to the power transmission coil,
The power transmission coil is:
A plurality of coils in which conductors are crossed on a predetermined plane in accordance with the unit of the first pitch along the predetermined direction, and a plurality of loop-shaped coils are formed by the conductors crossed on the predetermined plane. Has a unit,
The plurality of coil units are:
Arranged in a direction perpendicular to the direction along the predetermined plane, and the first pitch is formed with a different length,
When a constant voltage is applied to the conducting wires, the conduction directions of the currents flowing in the loop of the plurality of coils are opposite to each other at the intersection of the conducting wires,
The current control means includes
A non-contact power feeding apparatus, wherein the alternating currents flowing from the power source to the plurality of coil units have the same amplitude. The non-contact device according to claim 1.
The plurality of coil units are:
When the alternating current is passed, a magnetic field along the vertical direction is generated for each of the plurality of coils on the loop-shaped coil surface,
A synthesized magnetic field obtained by synthesizing the magnetic field components in the vertical direction out of the magnetic fields has a portion that strengthens and a portion that weakens for each predetermined region,
The predetermined area is:
The non-contact power feeding apparatus, wherein the coil unit having the shortest first pitch among the plurality of coil units corresponds to a coil surface formed in the loop shape. In the non-contact electric power feeder of Claim 1 or 2,
The plurality of coil units include, in order from the unit having the long first pitch, Nth (where N is a natural number of 2 or more) coil units,

The non-contact electric power feeder characterized by the above-mentioned.
However,
λ _N represents the length of the first pitch of the Nth coil unit,
lambda ₁ denotes the length of the first pitch of the first said coil unit. In the non-contact electric power feeder as described in any one of Claims 1-3,
The current control means includes
A non-contact power feeding apparatus that controls each phase of each of the alternating currents according to a position of the moving body that travels in the predetermined direction. In the non-contact electric power feeder of Claim 4,
The current control means includes
Among the plurality of coil units, the phase of the alternating current flowing through one coil unit is set as one phase,
Among the plurality of coil units, the phase of the alternating current flowing through the other coil units is set as another phase,
Controlling the phase of the alternating current flowing through the other coil unit by setting the other phase to the same phase or opposite phase with respect to the one phase according to the position of the moving body. The non-contact electric power feeder characterized by this. In the non-contact electric power feeder as described in any one of Claims 1-5,
The plurality of coil units are:
In order from the coil unit having the long first pitch, the coil unit includes up to Nth (where N is a natural number of 2 or more) coil units, and
In the predetermined plane, an energization range in which the alternating current can be supplied to the conducting wire is set for each predetermined length along the predetermined direction,
Each energization range of the plurality of coil units is:
Arranged to be shifted in the predetermined direction while overlapping on the coil surface of at least one of the coils,
Among the plurality of coil units, the energization range of the Mth (where M is a continuous natural number of 2 or more and N or less) coil units is:
The M-1 coil unit is shifted in the predetermined direction by a predetermined shift amount with respect to the energization range,
The predetermined displacement amount corresponds to a half length of the first pitch of the M-1 th coil unit. In the non-contact electric power feeder of Claim 6,
The current control means includes
A non-contact power feeding device that controls timing of energizing the alternating current to the energization range according to a position of the moving body traveling in the predetermined direction. In the non-contact electric power feeder as described in any one of Claims 1-7,
The power transmission coil is:
A single coil that is formed of a single loop-shaped coil in a plane parallel to the predetermined plane, and is arranged to overlap the plurality of coil units in the vertical direction;

The non-contact electric power feeder characterized by the above-mentioned.
However, when the plurality of coil units include coil units up to the Nth (where N is a natural number) in order from the unit having the long first pitch,
I _N represents the amplitude of the current flowing through the N-th coil unit,
n _N indicates the number of turns of the Nth coil unit,
S _N represents the area of the coil surface of one coil among the plurality of coils forming the Nth coil unit,
I _s represents the amplitude of the current flowing in said single coil,
n _s indicates the number of turns of the single coil;
S _s indicates the area of the coil surface of the single coil. In the non-contact electric power feeder as described in any one of Claims 1-8,
The power transmission coil is:
A plurality of groups of coil units including the plurality of coil units;
The plurality of groups are:
In the predetermined plane, the coil units having the same length of the first pitch are arranged adjacent to each other in a direction perpendicular to the predetermined direction,
The non-contact power feeding device according to claim 1, wherein conduction directions of the alternating currents flowing in a pair of adjacent coils among the plurality of coils forming the adjacent coil units are opposite to each other. In a non-contact power feeding device that supplies power in a non-contact manner by at least a magnetic action to a power receiving coil provided in a moving body that travels in a predetermined direction,
A power transmission coil that is electrically connected to a power source and transmits power in a contactless manner to the power reception coil;
Current control means for controlling an alternating current flowing from the power source to the power transmission coil,
The power transmission coil is:
In accordance with the unit of the second pitch along the predetermined direction, the coil unit has a coil unit in which a conducting wire is formed in a wave shape on a predetermined plane.
A first coil portion including a plurality of the wavy conductive wires having the length of the second pitch as a cycle; and a second coil portion including a plurality of the wavy conductive wires having the length of the second pitch as a cycle. Have
The first coil portion is
Each of the plurality of wavy conductive wires is shifted in the predetermined direction by a first shift amount,
The second coil part is
Each of the plurality of wavy conductive wires is shifted in a direction opposite to the predetermined direction by a second shift amount,
The current control means includes
The phase of the alternating current flowing through the plurality of wavy conductive wires of the first coil portion is made to correspond to the first shift amount,
The phase of the alternating current flowing through the plurality of wavy conductive wires of the second coil portion is made to correspond to the second shift amount,
The frequency of the alternating current that flows from the power source to the first coil unit and the frequency of the alternating current that flows from the power source to the second coil unit according to the speed of the moving body traveling in the predetermined direction. A non-contact power feeding device that is controlled. In the non-contact electric power feeder of Claim 10,
The first coil portion is
When the alternating current is passed, a magnetic field along a direction perpendicular to the direction along the predetermined plane is formed by a traveling wave toward the predetermined direction,
The second coil part is
A contactless power supply device, wherein when the alternating current is passed, a magnetic field along the vertical direction is formed by a backward wave directed in the opposite direction. In the non-contact electric power feeder of Claim 11,
The power transmission coil has a plurality of the coil units,
The plurality of coil units are:
A non-contact power feeding device, wherein the second pitch is formed to have a different length from each other in a direction perpendicular to a direction along the predetermined plane. The contactless power supply device according to claim 12,
The plurality of coil units include, in order from the long unit of the second pitch, up to Nth (where N is a natural number of 2 or more) coil units,
The current control means includes
Depending on the speed of the moving body, each frequency of the alternating current that flows through the first to Nth first coil sections, and the first to Nth second coil sections, respectively. A non-contact power feeding apparatus that controls each frequency of the alternating current to flow from the first to the Nth. In the non-contact electric power feeder as described in any one of Claims 10-13,
The plurality of wavy conductive wires included in the first coil portion are continuous single conductive wires,
The plurality of wavy conductive wires included in the second coil portion are continuous single conductive wires,
The AC power flowing from the power source to the first coil unit and the second coil unit is a single-phase AC current.

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