JP2012110080A - Non-contact type power transmission device, and, power supply device, power reception device, and electromagnetic induction coil used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve power transmission efficiency of a non-contact type power transmission device.SOLUTION: In a non-contact type power transmission device 1, an electric power is transferred between a power supply coil 20 and a power reception coil 31 by utilizing electromagnetic induction. A power supply device 10 is provided with a resonance circuit 13 which is configured by including the power supply coil 20. The power supply coil 20 comprises a plurality of flat coils 21 and 22, with the wires wound on the same axis, being a center, with the values of self inductance of them being almost identical. In this case, relating to a plurality of flat coils 21 and 22 constituting the power supply coil 20, a space is formed respectively at the center, with inner edge dimension and outer edge dimension of them decreasing sequentially. A flat coil having a small outer edge dimension is sequentially arranged at said space respectively, to form a single flat plane. Otherwise, the power supply coil comprises a group of a plurality of flat coils in which wires, arrayed side by side, are wound in spiral.

Description

  The present invention relates to a non-contact power transmission device that transmits electric power between a power feeding coil and a power receiving coil using electromagnetic induction, and a power feeding device, a power receiving device, and an electromagnetic induction coil used therefor.

  2. Description of the Related Art Conventionally, a non-contact power transmission device that transmits power from a power feeding device to a power receiving device using electromagnetic induction is known. FIG. 30 is an equivalent circuit diagram of a circuit of the non-contact power transmission apparatus 300. As shown in FIG. 30, the power feeding device 301 includes a resonance circuit in which a capacitor 302 and a coil are connected in series, and is configured to apply an AC voltage from an AC power source 304. A coil constituting the resonance circuit is a feeding coil 303. The resistor 305 shown in the figure represents the internal resistance Rp of the circuit that drives the capacitor. On the other hand, the power receiving device 310 includes a power receiving coil 311, and is arranged so that the power receiving coil 311 faces the power feeding coil 303 during power transmission. The resistor 312 shown on the power receiving device 310 side represents the load resistance RL.

  The non-contact power transmission apparatus 300 uses electromagnetic induction that gives the power receiving coil 311 the influence of the magnetic flux formed by the power feeding coil 303 in a state where the power feeding coil 303 and the power receiving coil 311 are arranged to face each other. .

  In recent years, in the field of mobile terminals and the like, attempts have been made to use electromagnetic induction as a charging method (see, for example, Patent Document 1).

  However, the non-contact power transmission device has a drawback in that the transmission efficiency is low as compared with a normal transformer configured by winding a primary coil and a secondary coil around one magnetic body. For this reason, attempts have been made in the past to improve transmission efficiency in contactless power transmission devices (see, for example, Patent Document 2).

  In the invention disclosed in Patent Document 2, capacitors are connected in parallel to the primary side induction coil on the power feeding device side and the secondary side induction coil on the power reception device side in order to reduce power consumption, and power is fed by this parallel connection. An LC parallel resonance circuit is configured with a charger as a device and a cordless device as a power receiving device. In addition, the primary induction coil and the secondary induction coil are constituted by sheet coils, and they are opposed to each other with a predetermined gap in the charged state. The invention of Patent Document 2 adopts such a configuration so that mutual induction can be performed with an appropriate gap.

JP 2007-166663 A Japanese Patent Laid-Open No. 10-23677

  However, in order to improve the efficiency of electric power transmission, there is a limit naturally only by optimizing the gap between the feeding coil and the receiving coil. In order to improve the efficiency of electric power transmission, it is necessary to improve the electromagnetic induction capability itself. Moreover, in order to target small devices such as portable terminals, it is essential to improve the electromagnetic induction capability while reducing the size of the power transmission device.

  The present invention has been made in view of such a problem, and a non-contact power transmission device that can transmit power efficiently and efficiently while maintaining a small size of the power transmission device, and a power supply device used therefor And it aims at providing the coil for electromagnetic induction.

  (1) In the present invention, in order to solve the above-described problem, a power supply device including a power supply coil including a planar coil formed by winding a wire in a spiral shape, and a planar coil formed by winding the wire in a spiral shape A non-contact power transmission device that transmits power from the power feeding device to the power receiving device using electromagnetic induction between the power feeding coil and the power receiving coil. The power feeding device has a resonance circuit including the power feeding coil, and the power feeding coil is composed of a plurality of planar coils, and the plurality of planar coils have their strands centered on the same axis. A non-contact power transmission device characterized by being wound and having a self-inductance value of approximately the same value was employed.

  (2) In this non-contact power transmission device, the power supply coil is configured such that the plurality of planar coils form one plane.

  (3) Further, the plurality of planar coils constituting the feeding coil are formed such that a space portion is formed at the center and the inner edge dimension and the outer edge dimension are sequentially reduced, and the plurality of planar coils are The planar coils having small outer edge dimensions are sequentially arranged in the space portions, and the plurality of planar coils are connected in parallel.

  (4) In this case, the outer edge dimension of the planar coil arranged at the innermost of the planar coils constituting the power supply coil is formed to be substantially the same as the outer edge dimension of the power receiving coil. .

  (5) Further, the planar coil constituting the feeding coil is formed by two planar coils arranged at least on the innermost side, in which two strands arranged in parallel are wound around the same axis. The two planar coils are configured in parallel, and are connected in parallel so that the number of turns of each of the two planar coils is smaller than the number of turns of the power receiving coil.

  (6) Alternatively, the planar coil arranged at least in the innermost of the planar coils constituting the feeding coil is a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis. Each planar coil constituting the planar coil group is wound less than the number of turns of the power receiving coil, and a current is passed through the planar coil selected from the planar coil group.

  (7) Alternatively, among the planar coils constituting the feeding coil, the planar coil arranged at least in the innermost part is a plane formed by winding at least four strands arranged in parallel around the same axis. Each planar coil that is configured of a coil group and that constitutes the planar coil group is wound less than the number of turns of the power receiving coil, and at least one strand is sandwiched between each of the planar coil groups. A planar coil constituted by a plurality of selected strands may be connected in parallel so that a current flows.

  (8) In such a case, the power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis, and the power receiving coil of the planar coil group on the power receiving side It is further preferable that a planar coil selected from among them is used for electromagnetic induction.

  (9) Moreover, in the non-contact power transmission device according to the present invention, the feeding coil is configured by two planar coils formed by winding two strands arranged in parallel around the same axis. The two planar coils are connected in parallel.

  (10) Alternatively, the power supply coil is configured by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis, and each planar coil constituting the planar coil group includes: The coil may be formed by winding less than the number of turns of the power receiving coil, and a current may be passed through a planar coil selected from the planar coil group.

  (11) Alternatively, the power supply coil is configured by a planar coil group formed by winding at least four strands arranged in parallel around the same axis, and each planar coil constituting the planar coil group Is arranged in parallel with a plurality of strands selected from the group of planar coils, with at least one strand sandwiched between them. It can also be configured to be connected to allow current to flow.

  (12) In such a case, the power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis, and the power receiving side planar coil. A planar coil selected from the group may be used for electromagnetic induction.

  (13) Moreover, in the non-contact power transmission device according to the present invention, the feeding coil is configured by two planar coils, and the two planar coils are connected in series.

  (14) In this case, the two planar coils are formed by winding two strands arranged in parallel around the same axis, and the innermost strands of each planar coil are connected to each other. It is good to comprise so that.

  (15) Further, in order to solve the above-described problems, the present invention provides a power receiving coil comprising a planar coil formed by winding a wire in a spiral shape from a feeding coil comprising a planar coil formed by winding the wire in a spiral shape. The power supply device is used to transmit power using electromagnetic induction. The power supply device includes a resonance circuit including the power supply coil, and the power supply coil includes a plurality of power supply coils. Each of the plurality of planar coils is formed of a planar coil, and the feeder is formed by winding the strands around the same axis, and the self-inductance value of each other is substantially the same.

  (16) The power supply coil is characterized in that the plurality of planar coils are configured as one plane.

  (17) In the power feeding device, the plurality of planar coils constituting the power feeding coil are formed such that a space portion is formed at the center, and the inner edge dimension and the outer edge dimension are sequentially reduced, A plurality of planar coils are characterized in that planar coils having small outer edge dimensions are sequentially arranged in the space portions, and the plurality of planar coils are connected in parallel.

  (18) In this case, at least the planar coil arranged in the innermost of the planar coils constituting the feeding coil is formed by winding two strands arranged in parallel around the same axis. It is good to comprise so that it may be comprised by two planar coils and the said two planar coils may be connected in parallel.

  (19) Alternatively, among the planar coils constituting the power supply coil, the planar coil arranged at least in the innermost part is a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis. It can also be configured such that a current flows through a planar coil selected from the planar coil group.

  (20) Alternatively, at least the planar coil arranged in the innermost of the planar coils constituting the feeding coil is a plane formed by winding at least four strands arranged in parallel around the same axis. A current is flowed by connecting in parallel a plurality of strands composed of a plurality of strands selected from among the planar coils and sandwiching at least one strand therebetween. You may comprise as follows.

  (21) In the present invention, in the above-described power supply device, the power supply coil includes two planar coils formed by winding two strands arranged in parallel around the same axis, and the 2 Two planar coils are connected in parallel.

  (22) Alternatively, the feeding coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis, and is alternatively selected from the planar coil group A current may be passed through the planar coil formed.

  (23) Alternatively, the power supply coil is configured by a planar coil group formed by winding at least four strands arranged in parallel around the same axis, and each of the planar coil groups includes: A planar coil composed of a plurality of strands selected with at least one strand interposed therebetween may be connected in parallel so that current flows.

  (24) Further, in the above-described power supply apparatus, the power supply coil includes two planar coils, and the two planar coils are connected in series.

  (25) In this case, the two planar coils are formed by winding two strands arranged in parallel around the same axis, and the innermost strands of each planar coil are connected to each other. It is good to comprise so that.

  (26) Further, in the present invention, in order to solve the above-described problem, a power receiving coil including a planar coil formed by winding a wire in a spiral shape from a power feeding coil including a planar coil formed by winding the wire in a spiral shape. A power receiving device used for transmitting electric power using electromagnetic induction, wherein the power receiving coil is a plane formed by winding a plurality of parallel wires arranged around the same axis. A power receiving device that is configured by a coil group and that uses a planar coil selected from the planar coil group on the power receiving side for electromagnetic induction is employed.

  (27) Further, in the present invention, in order to solve the above-described problem, a power feeding coil including a planar coil formed by winding a wire in a spiral shape, and a power receiving coil including a planar coil formed by winding the wire in a spiral shape An electromagnetic induction coil used in a non-contact power transmission device that transmits electric power using electromagnetic induction between the power supply coil and the plurality of planar coils. Has adopted a coil for electromagnetic induction in which the element wires are wound around the same axis and the self-inductance values of the elements are substantially the same.

  (28) With respect to this electromagnetic induction coil, the power supply coil is characterized in that the plurality of planar coils are formed in one plane.

  (29) In addition, regarding the electromagnetic induction coil, the plurality of planar coils constituting the power supply coil are formed such that a space portion is formed at the center and the inner edge dimension and the outer edge dimension are sequentially reduced. The plurality of planar coils are characterized in that planar coils having small outer edge dimensions are sequentially arranged in the space portions, and the plurality of planar coils are connected in parallel.

  (30) In this case, it is preferable that the outer edge dimension of the planar coil arranged at the innermost of the planar coils constituting the power feeding coil is formed to be substantially the same as the outer edge dimension of the power receiving coil.

  (31) Further, in the electromagnetic induction coil, at least two of the planar coils arranged in the innermost of the planar coils constituting the feeding coil are wound around the same axis. The two planar coils are connected in parallel so that the number of turns of each of the two planar coils is smaller than the number of turns of the power receiving coil.

  (32) Alternatively, among the planar coils constituting the power supply coil, the planar coil arranged at least in the innermost part is a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis. Each planar coil that constitutes the planar coil group is formed by winding less than the number of turns of the power receiving coil, and the planar coil group includes the planar coils that constitute the planar coil group. You may make it provide the connection terminal which enables selection of the planar coil which sends an electric current.

  (33) Alternatively, at least the planar coil arranged at the innermost of the planar coils constituting the feeding coil is a plane formed by winding at least four strands arranged in parallel around the same axis. Each planar coil that is constituted by a coil group and that constitutes the planar coil group is formed by winding less than the number of turns of the power receiving coil, and the planar coil group includes each planar coil that constitutes the planar coil group. A plurality of planar coils through which a current flows can be selected, and a selection terminal is provided by sandwiching a wire of another non-selected planar coil between them, and the selected planar coils are connected in parallel. You may do it.

  (34) In such a case, an identification means for distinguishing from other planar coils may be provided on the wire constituting the planar coil to be selected.

  (35) Further, in the case where a power feeding coil is configured like the above-described electromagnetic induction coil, the power receiving coil is a planar coil formed by winding a plurality of strands arranged in parallel around the same axis. The planar coil group on the power receiving side is provided with a connection terminal capable of selecting a planar coil used for electromagnetic induction from the planar coil group.

  (36) Even in this case, it is preferable to provide identification means for distinguishing the other planar coils from the strands constituting the planar coil to be selected.

  (37) In the present invention, in the above-described electromagnetic induction coil, the planar coil constituting the feeding coil is formed by two planes formed by winding two parallel wires arranged around the same axis. The two planar coils are configured in parallel, and the number of turns of each of the two planar coils is smaller than the number of turns of the power receiving coil.

  (38) Alternatively, the power supply coil is configured by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis, and each planar coil constituting the planar coil group includes: The number of turns of the power receiving coil is less than the number of turns of the power receiving coil, and the planar coil group is provided with a connection terminal that allows selection of a planar coil through which a current flows from each planar coil constituting the planar coil group.

  (39) Alternatively, the feeding coil is configured by a planar coil group formed by winding at least four strands arranged in parallel around the same axis, and each planar coil constituting the planar coil group Is wound less than the number of turns of the power receiving coil, and the planar coil group includes a plurality of planar coils that conduct current from among the planar coils that constitute the planar coil group, and other planar coil elements that are not selected. A selectable connection terminal is provided with a wire sandwiched between them, and the selected planar coils are connected in parallel.

  (40) In such a case, an identification means for distinguishing from other planar coils may be provided on the wire constituting the planar coil to be selected.

  (41) Further, in the electromagnetic induction coil, when the feeding coil is configured as described above, the power receiving coil is a plane formed by winding a plurality of strands arranged in parallel around the same axis. It is good to comprise so that it may be comprised by a coil group and the said flat coil group may be provided with the connecting terminal which can select the planar coil utilized for electromagnetic induction from each planar coil which comprises this planar coil group.

  (42) Also in this case, an identification means for distinguishing from other planar coils is provided on the strands constituting the planar coil to be selected.

  (43) In the electromagnetic induction coil according to the present invention, the feeding coil is configured by two planar coils, and the two planar coils are connected in series.

  (44) In this case, the two planar coils are formed by winding two strands arranged in parallel around the same axis, and the innermost strands of each planar coil are connected to each other. The

  According to the present invention, since the power feeding device constituting the non-contact power transmission device includes the resonance circuit, a resonance phenomenon is caused between the power feeding coil and the capacitor constituting the resonance circuit. As a result, it is possible to minimize the circuit impedance and maximize the obtained current to transmit the maximum power to the power receiving apparatus.

  In addition, although the power feeding coil of the power feeding device and the power receiving coil of the power receiving device interact with each other due to the mutual inductance and the coupling coefficient, the inductance value of the power feeding coil is reduced in order to reduce the Q value of the resonance circuit included in the power feeding device. Is lowered. By reducing the Q value on the power supply side in this way, the power receiving coil voltage can be increased in the region where the load resistance is low on the power receiving side. From this, the electromotive force of a receiving coil can be improved. On the other hand, in a region where the load resistance is high, the load resistance current can be reduced. Therefore, heat generation can be suppressed, and as a result, the electromotive force of the power receiving coil can be improved.

  Furthermore, according to the present invention, by reducing the Q value, the dependency of the receiving coil voltage on the load resistance value increases the receiving coil voltage in a region where the load resistance is small, and decreases the receiving coil voltage in a region where the load resistance is large. . That is, the change corresponding to the change can be reduced to flatten the voltage change, and the region depending on the load resistance can be widened. Thus, in the past, since the voltage change was large, an IC with a wide withstand voltage region had to be selected. However, an IC with a narrow withstand voltage region was selected by reducing and flattening the voltage change. It becomes possible to do.

  Also, when a power supply coil and a power reception coil are configured by a group of planar spiral coils composed of a plurality of spirally wound wires, and only the planar spiral coil selected from them is used for electromagnetic induction, it is used for electromagnetic induction. Between the strands of the planar spiral coil to be selected, the strands of the unselected planar spiral coil are interposed. For this reason, the strands of the planar spiral coil used for electromagnetic induction do not adhere to each other, and as a result, it is possible to effectively prevent the proximity effect from occurring.

It is a top view of the feeding coil and receiving coil which are used for the non-contact-type electric power transmission apparatus concerning 1st Embodiment of this invention. FIG. 2 is a cross-sectional view illustrating a state where a power feeding coil and a power receiving coil illustrated in FIG. 1 are opposed to each other. It is a block diagram which shows the outline | summary of the electric power transmission apparatus of this invention. It is an equivalent circuit diagram of the resonance circuit which the electric power feeder of this invention comprises. It is a top view of the feed coil comprised by the 3rd feed coil from the 1st feed coil concerning this invention. It is a top view of the feeding coil and receiving coil in which the external shape was formed in the hexagon. It is a top view of the feeding coil and receiving coil which are used for the non-contact-type electric power transmission apparatus concerning 2nd Embodiment of this invention. FIG. 8 is a cross-sectional view illustrating a state where the power feeding coil and the power receiving coil illustrated in FIG. 7 are opposed to each other. It is a top view of the feeding coil and receiving coil concerning 3rd Embodiment of this invention. FIG. 10 is an enlarged view of an AA cross section in a portion A of FIG. 9 in a state where the power feeding coil and the power receiving coil illustrated in FIG. 9 are opposed to each other. It is a top view of the feeding coil and receiving coil concerning 4th Embodiment of this invention. It is an enlarged view of the BB cross section in the B section of Drawing 11 in the state where the feeding coil and receiving coil shown in Drawing 11 were countered. It is a top view of the feeding coil and receiving coil concerning 5th Embodiment of this invention. It is an enlarged view of CC section in the C section of Drawing 13 in the state where the feed coil and receiving coil shown in Drawing 13 were countered. It is a top view of the feeding coil and receiving coil concerning 5th Embodiment concerning an Example different from the Example shown in FIG.13 and FIG.14. It is an enlarged view of the DD cross section in the D section of Drawing 15 in the state where the feeding coil and receiving coil shown in Drawing 15 were countered. It is a top view of the feeding coil and receiving coil concerning a 6th embodiment of the present invention. It is a top view of the feeding coil and receiving coil concerning 7th Embodiment of this invention. It is a top view of the feeding coil and receiving coil concerning 8th Embodiment of this invention. It is a top view of the feeding coil and receiving coil concerning 9th Embodiment of this invention. It is a top view of the feeding coil and receiving coil concerning 9th Embodiment concerning an Example different from the Example shown in FIG. It is a block diagram of the feed coil concerning a 10th embodiment of the present invention. It is a fragmentary sectional view in the feed coil shown in FIG. FIG. 24 is a partial cross-sectional view of a power feeding coil according to a tenth embodiment according to a different example from the power feeding coil illustrated in FIG. 23. It is a graph showing the simulation result about the relationship between load resistance at the time of using a general single type feeding coil and receiving coil voltage. It is a graph showing the simulation result about the relationship between load resistance at the time of using the feeding coil concerning the non-contact-type electric power transmission apparatus of this invention, and receiving coil voltage. It is the graph which showed the relationship of the receiving coil voltage with respect to load resistance regarding the non-contact-type electric power transmission apparatus of this invention and the non-contact-type electric power transmission apparatus using a common single type feeding coil. It is the graph which showed the relationship of the load resistance current with respect to load resistance regarding the non-contact-type electric power transmission apparatus of this invention and the non-contact-type electric power transmission apparatus using a general single type feeding coil. It is the graph which showed the relationship of the power consumption with respect to load resistance regarding the non-contact-type electric power transmission apparatus of this invention and the non-contact-type electric power transmission apparatus using a general single type feeding coil. It is the equivalent circuit schematic of the circuit used for the power transmission device using the conventional electromagnetic induction.

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

[First Embodiment]
FIG. 1 is a plan view of a power feeding coil 20 and a power receiving coil 31 that are electromagnetic induction coils 20 and 31 used in the contactless power transmission device 1 according to the first embodiment of the present invention, and FIG. The sectional view which looked at the state where coil 20 and receiving coil 31 were opposed to each other from the side is shown. FIG. 3 is a block diagram showing the basic principle of the contactless power transmission device 1 according to the first embodiment of the present invention, and FIG. 4 is an equivalent circuit diagram of the resonance circuit 13 included in the power feeding device 10. Show.

  First, the configuration of the contactless power transmission device 1 will be described with reference to FIGS. 3 and 4.

  The non-contact power transmission device 1 includes a power feeding device 10 and a power receiving device 30.

  The power feeding device 10 includes a resonance circuit 13 that supplies power to the power receiving device 30, a drive circuit 15 that drives the resonance circuit 13, and a control circuit 16 that controls the drive circuit 15. Further, in order to apply a voltage necessary for driving the power supply apparatus 10, a pulse wave is applied to the AC / DC conversion circuit 11 that rectifies an AC voltage supplied from the outside to generate a predetermined DC voltage, and a drive circuit 15. And a pulse wave transmission device 12 for applying.

  The AC / DC conversion circuit 11 is supplied with, for example, household AC power (AC 100V to 240V) via a power cable. The AC / DC conversion circuit 11 converts the supplied household AC voltage into a predetermined DC voltage, and outputs the converted DC voltage. The AC / DC conversion circuit 11 outputs the converted DC voltage to another circuit (not shown) included in the power supply apparatus 10 (for example, a communication control circuit that performs communication with an external device), and drives the other circuit. ing.

  The DC voltage output from the AC / DC conversion circuit 11 is input to the pulse wave transmission device 12. The pulse wave transmission device 12 outputs, for example, a 0 V-5 V pulse wave to the drive circuit 15. However, the voltage at the high level of the pulse wave transmitted from the pulse wave transmitter 12 may be an appropriate value according to the specification.

  The resonance circuit 13 includes an LC series circuit including a primary side capacitor 14 and a feeding coil 20, generates electromagnetic induction based on an output from the drive circuit 15, and receives a receiving coil 31 provided in the receiving device 30. AC voltage is generated. In this embodiment, the feeding coil 20 is configured by connecting two planar spiral coils 21 and 22 in parallel. 4 shows an LCR series circuit as the resonance circuit 13, reference numeral 17 shown in FIG. 4 represents the internal resistance Rp of the circuit for driving the capacitor.

  A pulse wave transmitted from the pulse wave transmission device 12 is input to the drive circuit 15. The drive circuit 15 outputs a pulse wave to the resonance circuit 13 while controlling whether or not to output the AC voltage input by the control circuit 16 to the resonance circuit 13.

  The control circuit 16 controls whether or not to drive the drive circuit 15 based on control of a control unit (not shown).

  On the other hand, the power receiving device 30 includes a power receiving coil 31 in which an electromotive force is generated by electromagnetic induction accompanying driving of the resonance circuit 13 of the power feeding device 10, and a power conversion circuit 32 that performs power conversion of the electromotive force generated in the power receiving coil 31. ing. Note that a load resistance generated in the circuit of the power receiving device 30 is denoted by reference numeral 33.

  The power receiving coil 31 generates a voltage at both ends of the power receiving coil 31 in accordance with the voltage applied to the power feeding coil 20 to generate an induced current, which is output to the power conversion circuit 32.

  The power conversion circuit 32 has a rectifier circuit, converts an input alternating current into a direct current, and outputs the direct current to a charger or an electronic device (not shown). For example, the rectifier circuit is configured by a diode bridge circuit.

  Next, the configuration of the electromagnetic induction coils 20 and 31 will be described with reference to FIGS.

  The feeding coil 20 includes a first feeding coil 21 disposed on the outside and a second feeding coil 22 disposed on the inside. Each of the first feeding coil 21 and the second feeding coil 22 is constituted by a flat planar spiral coil.

  The first feeding coil 21 is formed in a donut shape by winding the element wire 21 a in a spiral shape, and a space portion is provided at the center thereof, and the space portion is configured as a coil housing portion 25. On the other hand, the second feeding coil 22 is also formed by winding the strand 22a in a spiral shape, and a space portion where the strand 22a does not exist is provided at the center. That is, the second feeding coil 22 is an air-core planar spiral coil. The second feeding coil 22 is housed inside a coil housing portion 25 formed in the first feeding coil 21. In the state where the second feeding coil 22 is housed in the coil housing portion 25, the first feeding coil 21 and the second feeding coil 22 do not protrude from the first feeding coil 21 in the thickness direction of the feeding coil 20. The second power supply coil 22 forms a single plane. When the second feeding coil 22 is housed in the coil housing portion 25 of the first feeding coil 21, a gap of at least 1 mm is formed between the inner edge of the first feeding coil 21 and the outer edge of the second feeding coil 22. Good.

  The first feeding coil 21 and the second feeding coil 22 are connected in parallel so that both form a magnetic flux in the same direction. For example, when both the first feeding coil 21 and the second feeding coil 22 are formed by winding them from the outside in the clockwise direction, the strands 21 a and 22 a on the outer peripheral side of the first feeding coil 21 and the second feeding coil 22 are Are connected, and the strands 21a and 22a on the inner peripheral side of the first feeding coil 21 and the second feeding coil 22 are connected to each other, and both are connected in parallel.

  The first feeding coil 21 and the second feeding coil 22 are formed so that the inductance value of the first feeding coil 21 and the inductance value of the second feeding coil 22 are substantially the same value. As a result, when a current is passed through the power feeding coil 20, it is prevented from flowing only into either the first power feeding coil 21 or the second power feeding, and a current is passed through both the first power feeding coil 21 and the second power feeding. Ensure that it flows.

  On the other hand, the power receiving coil 31 is also composed of a planar spiral coil formed by winding the wire 31a in a spiral shape. The power receiving coil 31 has an outer diameter that is substantially the same as the outer diameter of the second power feeding coil 22, and a space portion in which the wire 31 a does not exist is formed at the center. That is, the feeding coil 20 is configured as an air-core planar spiral coil, and both the outer diameter and inner diameter are formed to be approximately the same size as the second feeding coil 22.

  When power is transmitted from the power feeding device 10 to the power receiving device 30 using the power feeding device 10 and the power receiving device 30 described above, the power feeding coil 20 and the power receiving coil 31 are opposed to each other as shown in FIG. This is done by generating electromagnetic induction between the two. When the power feeding coil 20 and the power receiving coil 31 are opposed to each other, the centers of the power feeding coil 20 and the power receiving coil 31 are matched as much as possible.

  Next, the basic principle of power transmission in the contactless power transmission device 1 according to the present embodiment will be described.

  In the non-contact power transmission device 1, power is transmitted from the power feeding device 10 to the power receiving device 30 using electromagnetic induction. That is, the electromotive force of the power receiving coil 31 included in the power receiving device 30 is affected by the magnitude of the magnetic flux that links the power receiving coil 31 with the magnetic flux formed by the power feeding coil 20. The magnitude of the magnetic flux formed by the feeding coil 20 is determined by the current flowing through the feeding coil 20. From this, it is important to increase the current flowing through the feeding coil 20 and reduce the generated voltage in order to improve the transmission efficiency and improve the electromotive force of the receiving coil 31.

  In this regard, in the contactless power transmission device 1 according to this embodiment, since the power feeding device 10 includes the resonance circuit 13, the resonance phenomenon occurs between the power supply coil 20 and the temporary capacitor 14 in the resonance circuit 13. Is causing. As a result, the digital signal is converted into a sinusoidal waveform, and in the resonance state, the impedance of the circuit is minimized and the obtained current is maximized. Maximum power is transmitted to the power receiving device 30 by utilizing such resonance of the power feeding device 10.

  When electromagnetic induction is used, the power of the power receiving coil 31 included in the power receiving device 30 is proportional to the square of the voltage and inversely proportional to the resistance value. For this reason, it is also important to prevent a voltage drop generated in the power receiving coil 31. More specifically, regarding the dependency of the load coil voltage on the load resistance RL, the power receiving coil voltage is increased in a region where the load resistance RL is low, while the power receiving coil voltage is decreased in a region where the load resistance RL is high. It is very important to keep the coil voltage constant with respect to the load resistance RL change.

  With respect to the above points, the power feeding device 10 includes the resonance circuit 13. In the resonance circuit 13, the voltage generated in the coil is affected by the Q value, and when the Q value is determined, the voltage generated in the coil is determined. The Q value is a value representing the degree and sharpness of resonance. A low Q value indicates that the resonance can be quickly controlled and stopped quickly, and conversely, the Q value is high. Means that resonance continues for a long time. This Q value is expressed by the following equation (1).

        Q = 1 / R × √ (L / C) (1)

  As apparent from the equation (1), the Q value is inversely proportional to the resistance value R and the square root value of the capacitance C, and is proportional to the square root value of the inductance L. In order to reduce the Q value, it is necessary to increase the resistance value R, increase the capacitance C, or decrease the inductance L.

  In this regard, if the resistance value R is increased, heat is generated, and if the capacitance C is increased, the resonance frequency is lowered. For this reason, it is optimal to reduce the inductance L.

  Here, the combined inductance in the case where the second feeding coil 22 is disposed inside the first feeding coil 21 as in the feeding coil 20 of the present embodiment is obtained. The combined inductance of the first feeding coil 21 and the second feeding coil 22 is LL, the inductance of the first feeding coil 21 is Lp1, and the inductance of the second feeding coil 22 is Lp2. The combined inductance LL can be expressed by the following equation (2) when expressed by Lp1 and Lp2.

        LL = Lp1 × Lp2 / (Lp1 + Lp2) (2)

  Now, assuming that the value of the inductance Lp2 of the second feeding coil 22 is the same as the value of the inductance Lp1 of the first feeding coil 21, the combined inductance LL can be expressed as Equation (3).

        LL = Lp1 / 2 (3)

  Thus, according to the power supply coil 20 of the power supply apparatus 10 according to the present embodiment, the value of the inductance can be reduced to about half compared to a general single type planar spiral coil.

  Thus, by reducing the inductance value of the power feeding coil 20, the Q value of the resonance circuit 13 included in the power feeding device 10 can be lowered. Then, by lowering the Q value of the power feeding device 10, in the power receiving device 30, the voltage of the power receiving coil 31 is kept more constant with respect to the change in the load resistance RL. A change corresponding to a change in the load resistance value of the coil voltage can be reduced to flatten the voltage change, and a region depending on the load resistance can be widened.

  As described above, the power receiving device 30 includes the power conversion circuit 32. Various ICs are used for the power conversion circuit 32. When a general single-type planar spiral coil was used, the change in voltage was large, so an IC with a wide withstand voltage region had to be selected, but the change in voltage decreased and became flat. As a result, it is possible to select an IC having a narrow withstand voltage region.

  As described above, the case of a double coil using two planar spiral coils as an example of the feeding coil has been described as an example. However, the present invention is not limited to this, and power is supplied using a multiple coil using three or more planar spiral coils. A coil may be formed.

  FIG. 5 shows a structure in which the feeding coil 40 is formed using three planar spiral coils.

  The power supply coil 40 is a flat spiral coil having a space formed at the center. Each planar spiral coil is formed so that the inner edge dimension and the outer edge dimension of each planar coil become smaller sequentially, and are arranged like a first feeding coil 41, a second feeding coil, and a third feeding coil in order from the outside.

  Specifically, the outer diameter of the second feeding coil 42 is smaller than the inner diameter of the first feeding coil 41, and the outer diameter of the third feeding coil 43 is smaller than the inner diameter of the second feeding coil 42. The first to third power supply coils 41, 42, and 43 are arranged inside the space where the second power supply coil 42 is formed at the center of the first power supply coil 41, and the third power supply coil 43 is The second feeding coil 42 is disposed inside the space formed in the center. Even in this case, a gap of 1 mm or more is provided between the inner edge of the first feeding coil 41 and the outer edge of the second feeding coil 42 and between the inner edge of the second feeding coil 42 and the outer edge of the third feeding coil 42. It is good to form.

  The first to third power supply coils 41, 42, and 43 have a planar shape without protruding from each other in the thickness direction of the power supply coil 40. Furthermore, the first to third power supply coils 41, 42, 43 are connected in parallel by connecting the strands located on the outermost circumference and connecting the strands located on the innermost circumference. Yes.

  Even when the feeding coil is formed of a plurality of planar spiral coils as described above, the outer diameter of the innermost planar spiral coil may be formed to be approximately the same as the outer diameter of the power receiving coil.

  As described above, the planar spiral coil has a circular outer shape as an example. However, the planar spiral coil may be formed in a polygonal shape such as a triangle, a quadrangle, a pentagon, or a hexagon.

  FIG. 6 shows an electromagnetic induction coil formed in a hexagon.

  The feeding coil 45 includes a first feeding coil 46 having a large outer dimension and a second feeding coil 47 having a small outer dimension. The first feeding coil 46 is wound in a spiral shape so that the outer shape thereof is a hexagon, and a space portion where no strand is present is formed at the center. Similarly, the second feeding coil 47 is also formed by winding a wire in a spiral shape so that the outer shape forms a hexagonal shape with a space formed in the center thereof. And the strand which comprises the 1st feed coil 46, and the strand which comprises the 2nd feed coil 47 are the center of the 1st feed coil 46 so that it may be comprised so that the same axis may become a center. The second power supply coil 47 is arranged inside the space portion formed in FIG.

  In addition, also about this feeding coil 45, the first feeding coil 46 and the second feeding coil have a planar shape without protruding from each other in the thickness direction. Further, a gap of 1 mm or more is preferably formed between the inner edge of the first power supply coil 46 and the outer edge of the second power supply coil 47.

  On the other hand, the power receiving coil 48 is also configured by winding a wire in a spiral shape so that its outer shape forms a hexagon. The power receiving coil 48 is formed so that the outer edge size and the inner edge size thereof are substantially the same as the outer edge size and the inner edge size of the second power feeding coil 47 disposed inside the power feeding coil 45.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS.

  As described above, in order to transmit power using electromagnetic induction, it is effective to lower the Q value of the resonance circuit 13 included in the power supply apparatus 10. Also in the second embodiment, the configuration is adopted to lower the Q value. In the second embodiment, only the configuration of the electromagnetic induction coils 50 and 60 is different from the non-contact power transmission device 1 according to the first embodiment, and the configuration of the other power feeding device 10 and the configuration of the power receiving device 30. Therefore, only the electromagnetic induction coils 50 and 60 will be described here.

  The power feeding coil 50 constituting the electromagnetic induction coils 50 and 60 is also composed of two planar spiral coils 51 and 52. The feeding coil 50 is configured such that the respective strands 51a and 52a constituting the two planar spiral coils 51 and 52 are arranged in parallel, and are wound in a spiral shape in the arranged state. When the feeding coils 50 are viewed in the radial direction by winding the strands 51a and 52a in a spiral shape, the strands 51a and 52a constituting the planar spiral coils 51 and 52 are viewed. Are arranged alternately. The formed feeding coil 50 forms one plane. Also for the power supply coil 50, the two planar spiral coils 51 and 52 are connected in parallel with the outermost strands 51a and 52a being connected to each other and the innermost strands 51a and 52a being connected to each other. Connected. In addition, also in this power supply coil 50, a space portion where the strands 51a and 52a do not exist is provided in the center portion, and an air-core planar spiral coil is formed.

  The two planar spiral coils 51 and 52 are formed of strands of the same material whose strand diameter and strand length are approximately the same, and the inductance values of the two spiral coils 51 and 52 are substantially the same.

  On the other hand, the power receiving coil 60 is a planar spiral coil configured by winding one strand 60a in a spiral shape. The outer diameter is formed to be approximately the same as the outer diameter of the feeding coil 50. In addition, a space portion where the strand 60a does not exist is formed at the center portion, and an air-core flat spiral coil is formed. The inner diameter of the space portion formed in the central portion is also formed to be approximately the same as the inner diameter of the space portion formed in the central portion of the feeding coil 50.

  When power transmission is performed using the power feeding coil 50 and the power receiving coil 60, the power feeding coil 50 and the power receiving coil 60 are opposed to each other as shown in FIG. At this time, they are arranged so that the centers of the two are substantially coincident.

  Next, the basic concept of the electromagnetic induction coils 50 and 60 according to the present embodiment will be described.

  Also in this embodiment, the basic idea is the same as that of the non-contact power transmission apparatus 1 according to the first embodiment in that the Q value is lowered by reducing the inductance value to improve the power transmission efficiency. In the power supply coil 50, the number of turns of the planar spiral coils 51 and 52 is reduced in order to reduce the inductance value. However, if the number of turns is simply reduced, the outer dimension of the feeding coil 50 is reduced. If it does so, the leakage of magnetic flux will arise between the feeding coil 50 and the receiving coil 60. FIG.

  For this reason, in order to maintain the outer dimension while reducing the number of turns of the feeding coil 50, the strands 51a and 52a constituting the two planar spiral coils 51 and 52 are arranged in parallel and arranged in an aligned state. The wire 51a, 52a is spirally wound to constitute the power supply coil 50.

  Also in the second embodiment, since the power feeding device 10 includes the resonance circuit 13 including the power feeding coil 50 as a component, the resonance circuit 13 causes a resonance phenomenon between the power feeding coil 20 and the capacitor 14. ing. As a result, the digital signal is converted into a sinusoidal waveform, and in the resonance state, the impedance of the circuit is minimized and the obtained current is maximized. Maximum power is transmitted to the power receiving device 30 by utilizing such resonance of the power feeding device 10.

  In addition, by forming the power supply coil 50 as in the second embodiment, the Q value of the resonance circuit 13 provided in the power supply apparatus 10 can be lowered, and the load resistance RL is related to the dependency of the power reception coil voltage on the load resistance RL. While the power receiving coil voltage is increased in the region where the load resistance is low, the power receiving coil voltage is decreased in the region where the load resistance RL is high, and the power receiving coil voltage can be made constant with respect to the change in the load resistance RL.

  Also in the second embodiment, the outer shape of the feeding coil and the receiving coil may be formed in a polygon such as a triangle, a quadrangle, a pentagon, and a hexagon.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a plan view of the power feeding coil 70 and the power receiving coil 80, and FIG. 10 is an enlarged view of the AA cross section in the portion A of FIG. is there. Also in this embodiment, only the configuration of the electromagnetic induction coils 70 and 80 is different from the non-contact power transmission device 1 according to the first embodiment, and other configurations of the power feeding device 10 and the power receiving device 30 Since the operation is the same as that shown in FIG. 3, only the electromagnetic induction coils 70 and 80 will be described.

  The feeding coil 70 is composed of a group of three planar spiral coils 71, 72, 73. In the power supply coil 70, the strands constituting the planar spiral coils 71, 72, 73 are arranged in parallel, and these three strands are wound in a spiral shape around one central axis to form a planar shape. Is formed. These three planar spiral coils 71, 72, 73 are formed of strands of the same material having the same strand diameter and strand length. For this reason, the inductance values of the three planar spiral coils are substantially the same value.

  When the outermost periphery of the power supply coil 70 is the first circumference of the power supply coil 70, as shown in FIG. 10, the strands of the planar spiral coil 71 are located outside and the planar spiral coil is located at the center on each circumference. 72 strands are located, and the strands of the planar spiral coil 73 are located inside. FIG. 10 shows from the nth to n + 4th cycles counted from the outside.

  In the feeding coil 70, connection terminals are provided at the ends of the respective strands on the outermost and innermost circumferences of the planar spiral coils 71, 72, 73. As a result, these connection terminals are selected and connected to the resonance circuit 13, and any one of the three planar spiral coils 71, 72, 73 can be selected selectively. Current is applied only to the selected planar spiral coil and used for electromagnetic induction. For example, as shown in FIGS. 9 and 10, the plane spiral coil 72 is selected and connected to the resonance circuit 13, and the other plane spiral coils 71 and 73 are not connected to the resonance circuit 13, thereby Only 72 is used for electromagnetic induction. However, other planar spiral coils may be selected.

  On the other hand, the power receiving coil 80 is formed in a flat shape by winding a single wire in a spiral shape. The power receiving coil 80 uses a wire having the same diameter as the wire of the three planar spiral coils 71, 72, 73 constituting the power supply coil 70, and has an outer diameter and an inner diameter of the power supply coil 70. The outer diameter and the inner diameter are substantially the same.

  Thus, when the power feeding coil 70 and the power receiving coil 80 are formed, the power feeding coil 70 is used for electromagnetic induction since only one of the three planar spiral coils is used for electromagnetic induction. The number of turns of the planar spiral coil of the power feeding coil 70 is 1/3 of the number of turns of the power receiving coil 80.

  In the third embodiment, the inductance value can be reduced by reducing the number of turns of the planar spiral coil used for electromagnetic induction in the power supply coil 70, and as a result, the Q value is lowered.

  Also in the third embodiment, since the power feeding device 10 includes the resonance circuit 13 including the power feeding coil 50 as a component, a resonance phenomenon occurs between the power feeding coil 20 and the capacitor 14 in the resonance circuit 13. I am letting. As a result, the digital signal is converted into a sinusoidal waveform, and in the resonance state, the impedance of the circuit is minimized and the obtained current is maximized. Maximum power is transmitted to the power receiving device 30 by utilizing such resonance of the power feeding device 10.

  In addition, by reducing the Q value of the resonance circuit 13 included in the power supply device 10, the dependency of the load resistance RL on the power reception coil voltage is increased in the region where the load resistance RL is low, while the load resistance RL is increased. In a high region, the power receiving coil voltage can be reduced to make the power receiving coil voltage constant with respect to the load resistance RL change.

  Further, in the third embodiment, since any one of the three planar spiral coils 71, 72, 73 is used in the power feeding coil 70, the wire located inside the power feeding coil 70 and the outside are positioned. A so-called proximity effect does not occur between the strands to be connected. For example, as shown in FIG. 10, when the planar spiral coil 72 is selected and an electric current is supplied only to the planar spiral coil 72, the planar spiral that is not selected is inserted between the strands constituting the planar spiral coil 72. There are strands of the coil 71 and the planar spiral coil 73. For this reason, the strands of the planar spiral coil 72 do not adhere to each other, and the proximity effect does not occur.

  In the power supply coil 70, the planar spiral coil to be selected is distinguished from other planar spiral coils by coloring the wire of the planar spiral coil to be selected or marking the terminal portion such as a vinyl tube. It is preferable to provide identification means for this purpose.

  As described above, the case where the power feeding coil is configured by a group of three planar spiral coils has been described. However, the present invention is not limited to this, and the power feeding coil is configured by a group of two planar spiral coils, or four or more planar spiral coils. You may comprise a feed coil by the group of. Even when the power feeding coil is constituted by a group of planar spiral coils other than three, one that is connected to the resonance circuit and used for electromagnetic induction is alternatively selected.

  In this way, by configuring the power supply coil with a plurality of N-turn planar spiral coil groups, the inductance value can be reduced to 1 / N with respect to the inductance value of the power receiving coil. And the inductance ratio of a feeding coil and a receiving coil can be arbitrarily set by forming a feeding coil in a desired number of turns. In addition, by configuring the coil to be used for electromagnetic induction to be selected from N, the strands through which current flows are not in close contact with each other, and the generation of the proximity effect can be effectively prevented.

  In the third embodiment, the outer shape of the feeding coil and the receiving coil may be formed in a polygon such as a triangle, a quadrangle, a pentagon, and a hexagon.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 11 is a plan view of the power feeding coil 90 and the power receiving coil 100 used in the non-contact power transmission apparatus according to the fourth embodiment, and FIG. 12 is related to the power feeding coil 90 and the power receiving coil 100 facing each other. 11 is an enlarged partial cross-sectional view of the B section of the 11 B section.

  The feeding coil 90 is constituted by a group of four planar spiral coils 91, 92, 93, 94. The group of four planar spiral coils 91, 92, 93, 94 is formed in a planar shape so that four strands arranged in parallel are wound in a spiral shape around the same axis. FIG. 12 shows the arrangement of the n-th element wire and the (n + 1) -th element wire from the outside with respect to each of the planar spiral coils 91, 92, 93, 94 constituting the power feeding coil 90. In each circumference, the strands of the planar spiral coils 91, 92, 93, 94 are the strands of the planar spiral coil 91, the strands of the planar spiral coil 92, the strands of the planar spiral coil 93, and the planar spiral coil 94 from the outside. Are arranged in the order of the strands.

  The planar spiral coils 91, 92, 93, 94 constituting the power supply coil 90 have the same wire diameter. Further, the wire lengths of the planar spiral coils 91, 92, 93, 94 are formed to be approximately the same size. For this reason, the inductance value of each planar spiral coil 91, 92, 93, 94 is substantially the same value.

  On the other hand, the power receiving coil is configured by a single wire wound in a spiral shape and formed in a planar shape. Since the outer diameter of the power feeding coil is formed to be approximately the same as the outer diameter of the power receiving coil, each planar coil constituting the power feeding coil is ¼ the number of turns of the power receiving coil.

  And also with respect to 90 in this feeding coil, connection terminals are provided at the ends of the respective strands at the outermost and innermost circumferences of the respective planar spiral coils 91, 92, 93, 94. Thus, a desired coil can be selected from the four planar spiral coils 91, 92, 93, 94 by selecting and connecting these connection terminals to the resonance circuit 13. The feeding coil 90 includes a planar spiral coil 91 wound so that the strands are positioned on the outermost side among the four planar coil groups constituting the feeding coil 90, and 3 from the outside of the coil group. The planar spiral coil 93 located at the second position is selected, and the two planar spiral coils 91 and 93 are connected to a resonance circuit and used for electromagnetic induction. By selecting the two planar spiral coils 91 and 93, the planar spiral coil 92 is interposed between the planar spiral coil 91 and the planar spiral coil 93 in the nth cycle, and the nth cycle In the (n + 1) th round, the planar spiral coil 94 is interposed between the planar spiral coil 91 and the planar spiral coil 93.

  As described above, in the power supply coil 90, the planar spiral coil that is not selected is interposed between the planar spiral coils that are selected for use in electromagnetic induction, and the strand of the planar spiral coil that is used for electromagnetic induction. It is configured so that they are not in close contact with each other.

  The two selected planar spiral coils 91 and 93 are connected to each other in the outermost periphery, and are connected in parallel with the innermost strands connected to each other. The strands of the two selected planar spiral coils 91 and 93 are colored to distinguish them from the other planar spiral coils 92 and 94, or a mark such as a vinyl tube is attached to the terminal portion. Can be identified.

  By configuring as described above, also in the fourth embodiment, the inductance value of the feeding coil 90 can be reduced, and as a result, the Q value is lowered. In the resonance circuit 13 of the power supply device 10 including the power supply coil 90, a resonance phenomenon occurs between the power supply coil 20 and the capacitor 14, the digital signal is converted into a sine waveform, and the impedance of the circuit is in the resonance state. Is minimized and the resulting current is maximized. Maximum power is transmitted to the power receiving device 30 by utilizing such resonance of the power feeding device 10.

  In addition, by reducing the Q value of the resonance circuit 13 included in the power supply device 10, the dependency of the load resistance RL on the power reception coil voltage is increased in the region where the load resistance RL is low, while the load resistance RL is increased. In a high region, the power receiving coil voltage can be reduced to make the power receiving coil voltage constant with respect to the load resistance RL change.

  Furthermore, since the planar spiral coil selected for use in electromagnetic induction in the power supply coil 90 has a plane spiral coil that is not selected interposed therebetween, the strands of the planar spiral coil used for electromagnetic induction are connected to each other. They do not adhere to each other and do not produce a proximity effect.

  Although the case where the planar spiral coils 91 and 93 are selected has been described above, the feeding coil 90 may be configured by selecting the planar spiral coils 92 and 94. In this case, unselected strands of the planar spiral coils 91 and 93 are interposed between the strands of the selected planar spiral coils 92 and 94. For this reason, generation | occurrence | production of a proximity effect can be prevented.

  Moreover, although the case where the feeding coil is four planar spiral coils has been described as an example, the feeding coil may be configured by a group of five or more planar spiral coils. Also in this case, the feeding coil is configured such that the element wires of the unselected planar spiral coil are interposed between the planar spiral coils selected for use in electromagnetic induction.

  Also in the fourth embodiment, by changing the number of planar spiral coils constituting the feeding coil and changing the ratio between the number of turns of each planar spiral coil and the number of windings of the receiving coil, the inductance of the feeding coil and the receiving coil The inductance ratio can be set freely.

  Also in the fourth embodiment, the outer shape of the feeding coil and the receiving coil may be formed in a polygon such as a triangle, a quadrangle, a pentagon, and a hexagon.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to FIGS. FIG. 13 is a plan view of the power feeding coil 110 and the power receiving coil 120, and FIG. 14 is an enlarged view of a CC cross section at a portion C in FIG. 13 in the power feeding coil 110 and the power receiving coil 120 opposed to each other. It is. Also in this embodiment, only the configuration of the electromagnetic induction coils 70 and 80 is different from the non-contact power transmission device 1 according to the first embodiment, and other configurations of the power feeding device 10 and the power receiving device 30 Since the operation is the same as that shown in FIG. 3, only the electromagnetic induction coils 110 and 120 will be described.

  The feeding coil 110 is composed of a group of three planar spiral coils 111, 112 and 113. The feeding coil 110 is formed by arranging the strands constituting the planar spiral coils 111, 112, and 113 in parallel, and winding these three strands in a spiral shape around one central axis. It is formed in a shape. These three planar spiral coils 111, 112, and 113 are formed of strands of the same material that have the same wire diameter and strand length. For this reason, the inductance values of the three planar spiral coils 111, 112, 113 are substantially the same.

  As shown in FIG. 14, when the outermost circumference of the power supply coil 110 is the first circumference, as shown in FIG. 14, the strand of the planar spiral coil 111 is located on the outer side and the element of the planar spiral coil 112 is located at the center. The wire is located, and the strand of the planar spiral coil 113 is located inside. FIG. 14 shows the outer nth and n + 1th turns.

  The feeding coil 110 is also provided with a terminal at the end of each strand, and any one of the three planar spiral coils 111, 112, 113 can be selected alternatively. The current is passed only through the selected planar spiral coil and used for electromagnetic induction. For example, as shown in FIGS. 13 and 14, the planar spiral coil 112 is selected and connected to the resonant circuit 13, and the other planar spiral coils 111 and 113 are not connected to the resonant circuit. Only for electromagnetic induction. However, other planar spiral coils may be selected.

  On the other hand, the power receiving coil 120 includes two planar spiral coils 121 and 122. The power receiving coil 120 is formed in a planar shape by winding two strands arranged in parallel in a spiral shape. The power receiving coil 120 uses a wire having the same diameter as the wire of the three planar spiral coils 111, 112, and 113 constituting the power feeding coil 110, and has an outer diameter and an inner diameter that are the same as those of the power feeding coil 110. The outer diameter and the inner diameter are substantially the same. A terminal is provided at the end of each strand of the planar spiral coils 121, 122, and either one of them can be connected to a circuit, and only one of the two planar spiral coils 121, 122 can be connected. Selected and used for electromagnetic induction.

  When the power supply coil 110 and the power reception coil 120 are formed as in the fifth embodiment, the inductance ratio of the planar spiral coil used for electromagnetic induction is 2: 3, and the power supply coil 110 is used for electromagnetic induction. The inductance value of the planar spiral coil is reduced, and as a result, the Q value is lowered.

  Also in the fifth embodiment, in the resonance circuit 13 of the power supply apparatus 10, a resonance phenomenon occurs between the power supply coil 20 and the capacitor 14, and the applied digital signal is converted into a sine waveform. In the resonance state, the impedance of the circuit is minimized and the obtained current is maximized. Maximum power is transmitted to the power receiving device 30 by utilizing such resonance of the power feeding device 10.

  In addition, by reducing the Q value of the resonance circuit 13 included in the power supply device 10, the dependency of the load resistance RL on the power reception coil voltage is increased in the region where the load resistance RL is low, while the load resistance RL is increased. In a high region, the power receiving coil voltage can be reduced to make the power receiving coil voltage constant with respect to the load resistance RL change.

  Furthermore, in this fifth embodiment, any of the wires of the planar spiral coil that is not selected is interposed between the strands of the planar spiral coil used for electromagnetic induction in any of the feeding coil 110 and the receiving coil 120. Therefore, the proximity effect can be prevented from occurring.

  For both the feeding coil 110 and the receiving coil 120, the planar spiral coil to be selected is selected by coloring the wire of the planar spiral coil to be selected or by marking the terminal portion such as a vinyl tube. Identification means for distinguishing from other planar spiral coils may be provided.

  The case where the power feeding coil is configured by a group of three planar spiral coils and the power receiving coil is configured by two planar spiral coils has been described above, but is not limited thereto, and the number of planar spiral coils constituting the power feeding coil is described. If the number of turns of the power feeding coil is made smaller than the number of turns of the power receiving coil, the power feeding coil and the power receiving coil are composed of other numbers of planar spiral coils. May be.

  In this way, the power supply coil is composed of a plurality of N-turn planar spiral coil groups, while the power receiving coil is comprised of a plurality of M-turn planar spiral coil groups, and the turns ratio is N: M (however, If N <M), the ratio between the inductance value of the feeding coil and the inductance value of the receiving coil can be set to N: M (where N <M). It becomes.

  When the inductance ratio between the power feeding coil and the power receiving coil can be freely changed, a power feeding coil and a power receiving coil may be provided as shown in FIGS.

  15 and 16 show another example in the fifth embodiment. FIG. 15 is a plan view of the power feeding coil 130 and the power receiving coil 140, and FIG. 16 is an enlarged view of a DD section of a portion D in FIG.

  The power supply coil 130 has the same configuration as that of the power supply coil 90 of the third embodiment, and includes a group of four planar spiral coils 131, 132, 133, and 134. The group of four planar spiral coils 131, 132, 133, and 134 is formed in a planar shape so that four strands arranged in parallel are wound in a spiral shape around the same axis. FIG. 16 shows the arrangement of the n-th element wire and the (n + 1) -th element wire from the outside for each of the planar spiral coils 131, 132, 133, and 134 constituting the power supply coil 130. In each circumference, the strands of the flat spiral coils 131, 132, 133, and 134 are the strands of the flat spiral coil 131, the flat spiral coil 132, the flat spiral coil 133, and the flat spiral coil 134 from the outside. Are arranged in the order of the strands.

  In addition, each planar spiral coil 131,132,133,134 is formed from the strand of the same material whose strand diameter and strand length are substantially the same dimension, and each planar spiral coil 131,132,133,134 is The inductance value is substantially the same value.

  On the other hand, the power receiving coil 140 includes two planar spiral coils 141 and 142. The power receiving coil 140 is formed in a flat shape by spirally winding two strands arranged in parallel. The power receiving coil 140 uses a wire having the same diameter as the wire of the four planar spiral coils 131, 132, 133, and 134 constituting the power supply coil 130, and has an outer diameter and an inner diameter of the power supply coil 140. The outer diameter and the inner diameter of 130 are substantially the same.

  In the feeding coil 130 in this embodiment, two planar spiral coils 131, 133 are selected from the four planar spiral coils 131, 132, 133, 134, and the selected two planar spiral coils 131, 133 are respectively The strands located on the outermost periphery are connected to each other, and the innermost strands are connected to be connected in parallel. Two planar spiral coils 131 and 133 are connected to the resonance circuit 13 and used for electromagnetic induction. For this reason, as shown in FIG. 16, unselected strands of the planar spiral coils 132 and 134 are interposed between the strands of the selected planar spiral coils 13 and 133.

  On the other hand, in the power receiving coil 140, only the planar spiral coil 141 is selected from the two planar spiral coils 141 and 142 and used for electromagnetic induction. FIG. 16 shows the wires of the planar spiral coils 141 and 142 constituting the power receiving coil 140 from the outside to the m-th to m + 4th rounds. As shown in FIG. Between the strands of the planar spiral coil 141 used, the strands of the planar spiral coil 142 that are not selected are interposed.

  Even when the power feeding coil 130 and one power receiving coil 140 which are electromagnetic induction coils are configured as in this embodiment, since the number of turns of the power feeding coil 130 is smaller than the number of turns of the power receiving coil 140, the inductance value of the power feeding coil is reduced. This can reduce the Q value.

  Even in this case, the power supply coil is configured by a desired number of planar spiral coil groups, and the power reception coil is configured by a desired number of planar spiral coil groups. As a result, the ratio between the inductance of the power feeding coil and the inductance of the power receiving coil can be set to a desired value. However, even in this case, it is necessary to make the number N of turns of the feeding coil smaller than the number M of turns of the receiving coil.

  In the fifth embodiment as well, the outer shape of the feeding coil and the receiving coil may be formed in a polygon such as a triangle, a quadrangle, a pentagon, and a hexagon.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 17 is a plan view of the power feeding coil 150 and the power receiving coil 160 used in the contactless power transmission device according to the sixth embodiment.

  The feeding coil 150 includes a donut-shaped first feeding coil 151 disposed on the outside, and a second feeding coil 152 disposed on the inner side of the first feeding coil 151. Furthermore, the second feeding coil 152 includes: It is composed of a group of two planar spiral coils 153 and 154. That is, the power feeding coil 20 according to the first embodiment described above and the power feeding coil 50 according to the second embodiment are combined.

  The first feeding coil 151 is formed by winding a wire in a spiral shape into a flat donut shape, and a space portion where no wire is present is formed at the center thereof. The second power supply coil 152 is disposed inside the space formed at the center of the first power supply coil 151. The second feeding coil 152 configured by the group of the two planar spiral coils 153 and 154 is formed such that two strands arranged in parallel are wound around the same axis in a spiral shape. Yes. The first feeding coil 151 and the second feeding coil 152 are further arranged so that the same axis is the center.

  The power feeding coil 150 configured as described above is formed in a planar shape so that the first power feeding coil 151 and the second power feeding coil 152 do not protrude from each other in the thickness direction of the power feeding coil 150.

  The two planar spiral coils 153 and 154 constituting the second feeding coil are connected to each other in parallel with each other, with the innermost strands being connected to each other and the innermost strands being connected to each other. ing. Further, the two planar spiral coils connected in parallel and the first feeding coil 151 are connected in parallel with the outermost circumferences and the innermost circumferences connected to each other.

  The wire diameter, the wire length, and the material of the wire are selected so that the inductance values of the first feeding coil 151 and the planar spiral coils 153 and 154 are substantially the same value.

  On the other hand, the power receiving coil 160 is formed in a planar shape by winding one strand in a spiral shape. The outer diameter and inner diameter of the power receiving coil 160 are formed to be approximately the same as the outer diameter and inner diameter of the second feeding coil 152.

  Also in this embodiment, the power supply coil 150 can be obtained as a combined inductance of the first power supply coil 151 and the second power supply coil 152, and the second power supply coil 152 is composed of two planar spiral coils. Since the number of turns is small, the inductance value can be reduced. As a result, the Q value in the resonance circuit 13 in the power feeding device 10 can be reduced.

[Seventh Embodiment]
Next, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 18 is a plan view of the feeding coil 170 and the receiving coil 160 used in the non-contact power transmission apparatus according to the seventh embodiment. In addition, since the structure of the receiving coil in this embodiment is the same as that of the receiving coil 160 concerning said 6th Embodiment, it attaches | subjects the same code | symbol to drawing here and the description is abbreviate | omitted.

  The power supply coil 170 according to this embodiment is provided with a first power supply coil 171 on the outer side and a second power supply coil 172 on the inner side.

  The first feeding coil 171 is formed in a donut shape by winding a wire in a spiral shape. In the center, a space portion where no wire exists is formed.

  The second feeding coil 172 is composed of a group of three planar spiral coils 173, 174, and 175, and three strands arranged in parallel are spirally wound around the same axis to form a planar shape. Is formed. The three planar spiral coils 173, 174, and 175 are spirally wound around each circumference, the strands of the planar spiral coil 173 from the outside, the strands of the planar spiral coil 174 at the center, and the planar spiral coil 175 at the inside. They are arranged in the order of the strands. The second power supply coil 172 is disposed inside the space formed in the center of the first power supply coil 171. In this state, the first feeding coil 171 and the second feeding coil 172 are configured in a planar shape without protruding from each other in the thickness direction of the feeding coil 170.

  In this embodiment, the second feeding coil 172 can be selectively selected from the three planar spiral coils 173, 174, and 175. Only a planar spiral coil selected from the two is used. For example, in the example shown in FIG. 18, the planar spiral coil 175 is selected from the three planar spiral coils 173, 174, and 175 and used for electromagnetic induction. In this feed coil 170, the planar spiral coil 175 and the first feed coil 171 selected in the second feed coil 172 are connected to the outermost strands and the innermost strands. Both are connected in parallel. However, the planar spiral coil to be selected may be another planar spiral coil.

  In this embodiment, the strands constituting the first feeding coil 171 and the strands constituting the three planar spiral coils 173, 174, 175 in the second feeding coil 172 are the strand diameter, Inductance values are substantially the same, for example, by configuring the wire length and material to be the same.

  Also in this embodiment, in the feeding coil 170, the inductance value is decreased to lower the Q value. Further, in the second feeding coil 172, since the strands of the unselected planar spiral coils 173 and 174 are interposed between the strands of the selected planar spiral coil 175, it is possible to prevent the proximity effect from occurring. Also in this embodiment, the second feeding coil may be configured by a group of two planar spiral coils, or may be configured by a group of four or more planar spiral coils.

[Eighth Embodiment]
FIG. 19 is a plan view of the power feeding coil 180 and the power receiving coil 160 used in the non-contact power transmission apparatus according to the ninth embodiment of the present invention. In addition, also in this 8th Embodiment, since the structure of the receiving coil 160 is the same structure as the receiving coil 160 concerning 6th Embodiment, the description is abbreviate | omitted.

  The power feeding coil 180 according to this embodiment is provided with a first power feeding coil 181 on the outer side and a second power feeding coil 182 on the inner side.

  The first feeding coil 181 is formed in a donut shape by winding a wire in a spiral shape. In the center, a space portion where no wire exists is formed.

  On the other hand, the second feeding coil 182 is composed of a group of four planar spiral coils 183, 184, 185 and 186. The four planar spiral coils 183, 184, 185, and 186 are formed in a planar shape by winding four strands arranged in parallel around the same axis in a spiral shape. The second feeding coil 182 configured as a group of four planar spiral coils 183, 184, 185, and 186 is arranged in a spiral shape around each circumference from the outside, the strand of the planar spiral coil 183, the planar spiral coil 184. Are arranged in the order of the element wire, the element wire of the plane spiral coil 185, and the element wire of the plane spiral coil 186.

  In the second feeding coil 182, two planar spiral coils are selected from the four planar spiral coils 183, 184, 185, and 186 and used for electromagnetic induction. In the example shown in FIG. 19, two planar spiral coils 184 and 186 are selected. The selected planar spiral coils 184 and 186 are connected in parallel by connecting the outermost strands thereof and connecting the innermost strands. The planar spiral coils 184 and 186 connected in parallel and the first feeding coil are further connected in parallel by connecting the outermost strands and the innermost strands. However, the other two planar spiral coils 183 and 185 may be selected as the planar spiral coil to be selected.

  Also in this embodiment, the strands constituting the first feeding coil 181 and the strands constituting the four planar spiral coils 183, 184, 185, and 186 in the second feeding coil 182 have the strand diameter, Inductance values are substantially the same, for example, by configuring the wire length and material to be the same.

  Also in this embodiment, in the power feeding coil 180, the inductance value is decreased to lower the Q value. Further, in the second feeding coil 182, since the strands of the unselected planar spiral coils 183 and 185 are interposed between the strands of the selected planar spiral coils 184 and 186, it is possible to prevent the proximity effect from occurring. . Also in this embodiment, the second feeding coil may be configured by a group of five or more planar spiral coils.

[Ninth Embodiment]
Next, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 20 is a plan view of the power feeding coil 190 and the power receiving coil 200 used in the non-contact power transmission apparatus according to the ninth embodiment.

  The feeding coil 190 is provided with a first feeding coil 191 on the outside, and a second feeding coil 192 on the inside.

  The first power supply coil 191 is formed in a donut shape by winding a wire in a spiral shape. In the center, a space portion where no wire exists is formed.

  The second feeding coil 192 is composed of a group of three planar spiral coils 193, 194, and 195, and three strands arranged in parallel are spirally wound around the same axis to form a planar shape. Is formed. The three planar spiral coils 193, 194, and 195 are arranged in the order of the strands of the planar spiral coil 193, the strands of the planar spiral coil 194, and the planar spiral coil 195 from the outside on each circumference wound in a spiral shape. The second feeding coil 192 is disposed inside a space portion formed in the center of the first feeding coil 191, and the first feeding coil 191 and the second feeding coil 192 are related to the thickness direction of the feeding coil 170. It is configured in a planar shape without protruding from each other.

  In this embodiment, the second feeding coil 192 can alternatively select a desired one of the three planar spiral coils 193, 194, 195, and only the selected planar spiral coil is used for electromagnetic induction. Is done. FIG. 20 shows an example in which the planar spiral coil 195 is selected and used for electromagnetic induction. Furthermore, the selected planar spiral coil 195 and the first power supply coil 191 are connected to the outermost strands and the innermost strands, and the two are connected in parallel.

  In this embodiment, the strands constituting the first feeding coil 191 and the strands constituting the three planar spiral coils 193, 194, 195 have the strand diameter, strand length and material. For example, the inductance values are substantially the same, for example, by the same configuration.

  On the other hand, the power receiving coil 200 is composed of two planar spiral coils 201 and 102. The power receiving coil 200 is formed in a planar shape so that two strands arranged in parallel are wound around the same axis in a spiral shape. The planar spiral coils 201 and 202 are formed of strands having the same strand diameter, strand length, and material. Only one of the two planar spiral coils is selected, connected to the circuit of the power receiving device, and used for electromagnetic induction. The power receiving coil 200 has an outer diameter and an inner diameter that are substantially the same as the outer diameter and the inner diameter of the second feeding coil.

  By configuring the power feeding coil and the power receiving coil in this way, not only can the Q value be lowered on the power feeding side, but also the proximity effect that occurs between the strands in the power feeding coil and the power receiving coil can be prevented.

  Also in this embodiment, the number of planar spiral coil groups constituting the first feeding coil is configured to a desired number, the number of turns is configured to a desired number, and the number of planar spiral coil groups configuring the power receiving coil is By providing the desired number of turns and configuring the desired number of turns, it is possible to freely set the ratio between the inductance value of the power feeding coil and the inductance value of the power receiving coil. However, in this case, it is necessary to make the number of turns of the feeding coil smaller than the number of turns of the receiving coil.

  In addition, regarding the case where the ratio between the inductance value of the power feeding coil and the inductance value of the power receiving coil is set freely, the power feeding coil and the power receiving coil can be configured as shown in FIG. FIG. 21 is a plan view of a power feeding coil 210 and a power receiving coil 200 according to another embodiment. In addition, since the structure of the receiving coil 200 in this Example is the same as that of the receiving coil shown in FIG. 20, the same code | symbol is attached | subjected to drawing and the description is abbreviate | omitted here.

  The power feeding coil 210 according to this embodiment is provided with a first power feeding coil 211 on the outer side and a second power feeding coil 212 on the inner side.

  The first feeding coil 211 is formed in a donut shape by winding a wire in a spiral shape. In the center, a space portion where no wire exists is formed.

  On the other hand, the second feeding coil 212 is composed of a group of four planar spiral coils 213, 214, 215, and 216. The four planar spiral coils 213, 214, 215, and 216 are formed in a planar shape in which four strands arranged in parallel are spirally wound around the same axis. The four planar spiral coils 213, 21, 215, and 216 are arranged in a spiral shape from the outside, from the outside, the strands of the planar spiral coil 213, the strands of the planar spiral coil 214, and the strands of the planar spiral coil 215. The planar spiral coils 216 are arranged in the order of the strands.

  In the second feeding coil 212, two planar spiral coils are selected and used for electromagnetic induction. When selecting, it selects so that the element wire of the plane spiral coil which is not selected may interpose between the element wire of the plane spiral coil to select. In the example shown in FIG. 19, two planar spiral coils 214 and 216 are selected. The selected planar spiral coils 214 and 216 are connected in parallel by connecting the outermost strands thereof and connecting the innermost strands. The planar spiral coils 214 and 216 and the first feeding coil 211 connected in parallel are further connected in parallel by connecting the outermost strands and the innermost strands.

  Also in this embodiment, the strands constituting the first feeding coil 211 and the strands constituting the four planar spiral coils 213, 214, 215, 216 have the strand diameter, strand length and material. For example, the inductance values are substantially the same, for example, by the same configuration.

  Also in this embodiment, the number of planar spiral coil groups constituting the first feeding coil is configured to a desired number, the number of turns is configured to a desired number, and the number of planar spiral coil groups configuring the power receiving coil is By providing the desired number of turns and controlling the number of turns to a desired number, the ratio of the inductance value of the power feeding coil and the inductance value of the power receiving coil can be freely set. However, in this case, it is necessary to make the number of turns of the feeding coil smaller than the number of turns of the receiving coil.

[Tenth embodiment]
Next, a tenth embodiment of the present invention will be described with reference to FIGS. FIG. 22 is a block diagram of a power feeding coil used in the non-contact power transmission apparatus according to the tenth embodiment, and FIG. 23 is a partial cross-sectional enlarged view of the power feeding coil.

  The power supply coil 220 is configured by connecting two planar spiral coils 221 and 222 in series. The two planar spiral coils 221 and 222 are formed in a planar shape, in which two strands arranged in parallel are wound in a spiral shape around the same axis. In addition, the formed feeding coil 220 is provided with a space where no strand exists at the center. The two planar spiral coils 221 and 222 are connected in series by being connected at the innermost circumference. That is, one planar spiral coil 221 is spirally wound from the outside to the inside, and a certain gap is formed between the strands. The other planar spiral coil 222 is formed such that a strand is disposed between the gaps formed between the strands of the planar spiral coil 221 and is wound spirally from the inside to the outside.

  In the case where the power supply coil is configured by connecting the planar spiral coils in series, as shown in FIG. 24, two planar spiral coils 231 and 232 may be stacked in the thickness direction. In the feeding coil 230 shown in FIG. 24, two planar spiral coils 231 and 232 are overlapped, and the strands are connected in series at the innermost periphery thereof.

  Heretofore, various embodiments of the contactless power transmission device of the present invention have been described. Next, it performed in order to confirm the efficiency of the power transmission in the non-contact-type power transmission apparatus of this invention. Simulation results and experimental results will be described.

  First, in order to confirm the power transmission efficiency in the non-contact power transmission apparatus 1 of the present invention, the following experiment was performed using the double coil type feeding coil described in the first embodiment.

  In the experiment, a pulse wave having a voltage of 1 V was applied to the resonance circuit 13 provided in the power supply apparatus 10 to obtain an inductance value and a resistance value. The frequency of the applied pulse wave was 1 kHz, 10 kHz, 100 kHz, 250 kHz, 500 kHz, and 1000 kHz. For comparison, an experiment was performed on a general single type planar spiral coil and a planar spiral coil including the first feeding coil 21 and the second feeding coil 22. An equivalent circuit diagram of a resonance circuit using this general planar spiral coil is shown in FIG.

  Table 1 shows the dimensions of the feeding coil 20 used in the experiment. In addition, a common single type feeding coil is a case where only the 2nd feeding coil 22 arrange | positioned inside in this embodiment is used.

  Table 2 shows the obtained inductance value and resistance value. In Table 2, a single coil means a general power supply coil, and a double coil means a power supply coil 20 according to this embodiment.

  As is apparent from Table 2, the power supply coil 20 according to the present embodiment has an inductance value and a resistance value at any frequency as compared with the case where a general single type planar spiral coil is used as the power supply coil. It can be seen that both are decreasing. In the inductance value, a decrease of 40% to 41.7% is observed, and in the resistance value, a decrease of 34.2% to 48% is observed.

  Further, the mutual inductance and the coupling coefficient when the frequency of the applied pulse wave was 1 kHz were determined. The physical use of the power receiving coil 31 used at this time is that the inner diameter of the coil is 10.45 mm, the outer diameter is 32.55 mm, the strand diameter is 0.52 mm, the number of turns is 19, and the inductance value is Is 7.26 μH.

  Table 3 shows the obtained mutual inductance value M and the coupling coefficient k.

  As shown in Table 3, the coupling coefficient k did not differ so much, but the mutual inductance value M was reduced by 29.7%.

  Second, a general power transmission device (hereinafter referred to as a single coil) in which the feeding coil is a single planar spiral coil and a non-contact power transmission device 1 (hereinafter referred to as a single coil) according to the first embodiment of the present invention. And the case of a double coil) are compared with the results of simulations performed to confirm how much difference occurs in the dependence characteristics of the receiving coil voltage on the load resistance RL. The simulation was performed for each of the three types having a coupling coefficient k of 0.5, 0.25, and 0.1.

  FIG. 25 shows a graph of a result of simulation for the case of a single coil, and FIG. 26 shows a graph of a result of simulation for a case of a double coil. 25 and 26, the horizontal axis indicates the load resistance of the circuit on the power receiving device side, and the vertical axis indicates the power receiving coil voltage.

  As is clear from the comparison between FIG. 25 and FIG. 26, it can be seen that the power receiving coil voltage increases when the load resistance is small and decreases when the load resistance is large. As described above, when the change in the receiving coil voltage with respect to the load resistance is large, when the power supply IC or the like is selected on the power receiving side, only those having a wide withstand voltage region can be selected. However, in the contactless power transmission device 1 of the present embodiment, it is clear from the simulation result that it is not necessary to select a device having a wide withstand voltage region on the power receiving side. That is, the types and widths of ICs that can be selected are expanded.

  Third, a general non-contact power transmission device (hereinafter referred to as a single coil) in which the feeding coil is a single planar spiral coil, and a non-contact power transmission device according to the first embodiment of the present invention. 1 (in the case of a double coil), a comparative experiment of power reception characteristics was conducted. In the experiment, a 5 V amplitude pulse wave with a frequency of 250 kHz is applied to the resonance circuit on the power supply side, the coupling coefficient between the power supply coil and the power reception coil is set to 0.25, and the load resistance RL is 5Ω on the power reception side. 10Ω, 25Ω, 50Ω, 75Ω, 100Ω, 250Ω, 500Ω, 750Ω, and 1000Ω, receiving coil end voltage Vout (however, voltage amplitude in the signal state), load resistance current Iout (however, in the signal state) Current amplitude). Then, based on the measurement results, the power consumption Pw at the load resistance, the DC conversion value Vdco of the receiving coil end voltage Vout, and the DC conversion value Idc of the load resistance current Iout were calculated, and the calculation results were compared.

  Based on the measurement results, the power consumption Pw at the load resistance, the DC converted value Vdco of the receiving coil end voltage Vout, and the DC converted value Idc of the load resistance current Iout are obtained by the following conversion formulas.

Pw = (Vout × Iout) / √2
Vdco = Vout / √2
Idc = Iout / √2

  Table 4 shows the experimental results in the case of a double coil, and Table 5 shows the experimental results in the case of a single coil.

  Then, for the receiving coil end voltage Vout, the load resistance current Iout, and the power consumption Pw shown in Tables 4 and 5, the case of the double coil and the case of the single coil are extracted and compared, respectively. 6 to Table 8. In addition, VoutD shown in the upper part of Table 6 represents the receiving coil end voltage Vout for the case of the double coil, and VoutS represents the receiving coil end voltage Vout for the single coil. Similarly, in Tables 7 and 8, the symbol “D” shown in the upper part represents the case of a double coil, and the symbol “S” represents the case of a single coil.

  27 to 29 are graphs showing changes in the receiving coil end voltage Vout, the load resistance current Iout, and the power consumption Pw with respect to the load resistance on the power receiving side based on the data in Tables 6 to 8.

  As shown in Table 6 and FIG. 27, the receiving coil end voltage Vout with respect to the load resistance is higher in the case of the double coil than in the case of the single coil when the load resistance is in the range of 1Ω to 25Ω. It has become. On the other hand, in the range of load resistance exceeding 25Ω and up to 1000Ω, in the case of a single coil, the voltage increases significantly as the load resistance increases, but in the case of a double coil, the load resistance increases. It can be seen that the increase in voltage does not increase so much, and the voltage difference with respect to the single coil gradually widens.

  On the other hand, as shown in Table 7 and FIG. 28, the load resistance current Iout with respect to the load resistance is larger in the case of the double coil than in the case of the single coil when the load resistance is in the range of 1Ω to 25Ω. The current value is large. On the other hand, in the range where the load resistance exceeds 25Ω and reaches 1000Ω, the current value is smaller in the case of the double coil than in the case of the single coil.

  As shown in Table 8 and FIG. 29, the power consumption Pw with respect to the load resistance is larger in the case of the double coil than in the case of the single coil when the load resistance is in the range of 1Ω to 25Ω. Yes. On the other hand, in the range where the load resistance exceeds 25Ω and up to 1000Ω, the power consumption Pw is smaller in the case of the double coil than in the case of the single coil.

  As is clear from the experimental results, by reducing the Q value on the power supply side, the power receiving coil end voltage Vout can be increased on the power receiving side when the load resistance is in the range of 1Ω to 25Ω. From this, the electromotive force of a receiving coil can be improved. On the other hand, in the range where the load resistance exceeds 25Ω, the load resistance current Iout can be reduced. Thus, heat generation can be suppressed, and as a result, the electromotive force of the power receiving coil can be improved.

  Furthermore, as described in the simulation result, it is understood that it is not necessary to select a power receiving side having a wide withstand voltage region by suppressing fluctuations in the receiving coil voltage with respect to the load resistance. That is, the types and widths of ICs that can be selected are expanded.

DESCRIPTION OF SYMBOLS 1 Power transmission apparatus 10 Power supply apparatus 11 AC / DC conversion circuit 12 DC / AC conversion circuit 13 Resonance circuit 14 Drive circuit 15 Control circuit 20 Power supply coil 21 First power supply coil 22 Second power supply coil 30 Power reception apparatus 31 Power reception coil 40 Power supply coil 41 1st feeding coil 42 2nd feeding coil 43 3rd feeding coil 45 feeding coil 46 1st feeding coil 47 2nd feeding coil 48 receiving coil 50 feeding coil 51, 52 planar spiral coil 60 receiving coil 70 feeding coil 71, 72, 73 Planar spiral coil 80 Power receiving coil 90 Feeding coil 91, 92, 93, 94 Planar spiral coil

DESCRIPTION OF SYMBOLS 100 Power receiving coil 110 Power feeding coil 111,112,113 Planar spiral coil 120 Power receiving coil 121,122 Planar spiral coil 130 Power feeding coil 140 Power receiving coil 141,142 Planar spiral coil 150 Power feeding coil 151 First power feeding coil 152 Second power feeding coil 153 154 planar spiral coil 160 power receiving coil 170 feeding coil 171 first feeding coil 172 second feeding coil 173, 174, 175 planar spiral coil 180 feeding coil 181 first feeding coil 182 second feeding coil 183, 184, 185, 186 planar spiral Coil 190 Feed coil 191 First feed coil 192 Second feed coil 193, 194, 195 Planar spiral coil

200 Power receiving coil 201, 202 Planar spiral coil 210 Feed coil 211 First feed coil 212 Second feed coil 213, 214, 215, 126 Plane spiral coil 220 Feed coil 221, 222 Plane spiral coil 230 Feed coil 231 232 Plane spiral coil

Claims (44)

A power feeding device including a power feeding coil made of a planar coil formed by winding a wire in a spiral shape; and a power receiving device equipped with a power receiving coil made of a planar coil formed by winding the wire in a spiral shape, the power feeding A non-contact power transmission device that transmits electric power from the power feeding device to the power receiving device using electromagnetic induction between a coil and the power receiving coil,
The power feeding device has a resonance circuit configured including the power feeding coil,
The feeding coil is composed of a plurality of planar coils, and the plurality of planar coils are formed by winding the strands around the same axis, and the self-inductance values of the coils are substantially the same. A contactless power transmission device.   The contactless power transmission device according to claim 1, wherein the feeding coil is configured such that the plurality of planar coils form one plane. The plurality of planar coils constituting the power supply coil are formed such that a space portion is formed in the center, and the inner edge dimension and the outer edge dimension of each other are sequentially reduced.
In the plurality of planar coils, planar coils having small outer edge dimensions are sequentially arranged in the space portions.
The contactless power transmission device according to claim 2, wherein the plurality of planar coils are connected in parallel.   The outer edge dimension of the planar coil arranged at the innermost of the planar coils constituting the power supply coil is formed to be substantially the same dimension as the outer edge dimension of the power receiving coil. Contact power transmission device. The planar coil constituting the feeding coil is composed of two planar coils formed by winding two strands arranged in parallel around the same axis, at least the planar coil arranged at the innermost part. And the two planar coils are connected in parallel,
The contactless power transmission device according to claim 3, wherein the number of turns of each of the two planar coils is smaller than the number of turns of the power receiving coil. The planar coil arranged at least at the innermost of the planar coils constituting the feeding coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
Each planar coil constituting the planar coil group is wound less than the number of turns of the power receiving coil,
The contactless power transmission device according to claim 3, wherein a current is passed through a planar coil selected from the planar coil group. Among the planar coils constituting the power supply coil, at least the planar coil arranged in the innermost part is composed of a planar coil group formed by winding at least four strands arranged in parallel around the same axis. ,
Each planar coil constituting the planar coil group is wound less than the number of turns of the power receiving coil,
The planar coil comprised of a plurality of strands selected from the planar coil group with at least one strand sandwiched therebetween is connected in parallel to pass a current. Item 5. The non-contact power transmission device according to Item 4. The power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
The contactless power transmission device according to claim 6 or 7, wherein a planar coil selected from the planar coil group on the power receiving side is used for electromagnetic induction. The feeding coil is composed of two planar coils formed by winding two strands arranged in parallel around the same axis,
The non-contact power transmission apparatus according to claim 2, wherein the two planar coils are connected in parallel. The feeding coil is composed of a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
Each planar coil constituting the planar coil group is formed by winding less than the number of turns of the power receiving coil,
The non-contact power transmission device according to claim 2, wherein a current is passed through a planar coil selected from the planar coil group. The feeding coil is constituted by a planar coil group formed by winding at least four strands arranged in parallel around the same axis,
Each planar coil constituting the planar coil group is wound less than the number of turns of the power receiving coil,
The planar coil comprised of a plurality of strands selected from the planar coil group with at least one strand sandwiched therebetween is connected in parallel to pass a current. Item 3. The non-contact power transmission device according to Item 2. The power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
The contactless power transmission device according to claim 10 or 11, wherein a planar coil selected from the planar coil group on the power receiving side is used for electromagnetic induction.   The contactless power transmission device according to claim 1, wherein the feeding coil includes two planar coils, and the two planar coils are connected in series. The two planar coils are formed by winding two strands arranged in parallel around the same axis,
The contactless power transmission device according to claim 13, wherein the innermost strands of each planar coil are connected to each other. Used to transmit power using electromagnetic induction from a feeding coil consisting of a planar coil formed by winding a strand to a receiving coil consisting of a planar coil formed by winding a strand. A power supply device,
The power feeding device has a resonance circuit configured including the power feeding coil,
The feeding coil is composed of a plurality of planar coils, and the plurality of planar coils are formed by winding the strands around the same axis, and the self-inductance values of the coils are substantially the same. Characteristic power supply device.   The power feeding device according to claim 15, wherein the power feeding coil is configured such that the plurality of planar coils form one plane. The plurality of planar coils constituting the power supply coil are formed such that a space portion is formed in the center, and the inner edge dimension and the outer edge dimension of each other are sequentially reduced.
In the plurality of planar coils, planar coils having small outer edge dimensions are sequentially arranged in the space portions.
The power feeding device according to claim 16, wherein the plurality of planar coils are connected in parallel.   The planar coil arranged at least at the innermost of the planar coils constituting the feeding coil is composed of two planar coils formed by winding two strands arranged in parallel around the same axis. The power feeding apparatus according to claim 17, wherein the two planar coils are connected in parallel. The planar coil arranged at least at the innermost of the planar coils constituting the feeding coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
The power feeding device according to claim 17, wherein a current is passed through a planar coil selected from the planar coil group. Among the planar coils constituting the power supply coil, at least the planar coil arranged in the innermost part is composed of a planar coil group formed by winding at least four strands arranged in parallel around the same axis. ,
The planar coil comprised of a plurality of strands selected from the planar coil group with at least one strand sandwiched therebetween is connected in parallel to pass a current. Item 18. The power feeding device according to Item 17. The feeding coil is composed of two planar coils formed by winding two strands arranged in parallel around the same axis,
The power feeding device according to claim 16, wherein the two planar coils are connected in parallel. The feeding coil is composed of a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
The power feeding device according to claim 16, wherein a current is caused to flow through a planar coil that is alternatively selected from the group of planar coils. The feeding coil is constituted by a planar coil group formed by winding at least four strands arranged in parallel around the same axis,
The planar coil comprised of a plurality of strands selected from the planar coil group with at least one strand sandwiched therebetween is connected in parallel to pass a current. Item 17. The power feeding device according to Item 16.   The power feeding device according to claim 15, wherein the power feeding coil includes two planar coils, and the two planar coils are connected in series. The two planar coils are formed by winding two strands arranged in parallel around the same axis,
The power feeding device according to claim 24, wherein the innermost strands of each planar coil are connected to each other. Used to transmit power using electromagnetic induction from a feeding coil consisting of a planar coil formed by winding a strand to a receiving coil consisting of a planar coil formed by winding a strand. A power receiving device,
The power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
A power receiving apparatus, wherein a planar coil selected from the group of planar coils on a power receiving side is used for electromagnetic induction. Non-contact transmission of electric power using electromagnetic induction between a feeding coil composed of a planar coil formed by winding a wire in a spiral shape and a power receiving coil composed of a planar coil formed by winding a wire in a spiral shape A coil for electromagnetic induction used in an electric power transmission device,
The feeding coil is composed of a plurality of planar coils, and the plurality of planar coils are formed by winding the strands around the same axis, and the self-inductance values of the coils are substantially the same. Characteristic coil for electromagnetic induction.   28. The electromagnetic induction coil according to claim 27, wherein the feeding coil is configured such that the plurality of planar coils form one plane. The plurality of planar coils constituting the power supply coil are formed such that a space portion is formed in the center, and the inner edge dimension and the outer edge dimension of each other are sequentially reduced.
In the plurality of planar coils, planar coils having small outer edge dimensions are sequentially arranged in the space portions.
29. The electromagnetic induction coil according to claim 28, wherein the plurality of planar coils are connected in parallel.   30. The electromagnetic wave according to claim 29, wherein an outer edge dimension of a planar coil arranged in an innermost part of the planar coils constituting the power supply coil is formed to be substantially the same as an outer edge dimension of the power receiving coil. Induction coil. Of the planar coils constituting the power supply coil, at least the planar coil arranged in the innermost part is composed of two planar coils formed by winding two strands arranged in parallel around the same axis. And the two planar coils are connected in parallel,
30. The electromagnetic induction coil according to claim 29, wherein the number of turns of each of the two planar coils is smaller than the number of turns of the power receiving coil. The planar coil arranged at least at the innermost of the planar coils constituting the feeding coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
Each planar coil constituting the planar coil group is formed by winding less than the number of turns of the power receiving coil,
30. The electromagnetic induction according to claim 29, wherein the planar coil group is provided with a connection terminal capable of selecting a planar coil that allows current to flow from each planar coil constituting the planar coil group. Coil. Among the planar coils constituting the power supply coil, at least the planar coil arranged in the innermost part is composed of a planar coil group formed by winding at least four strands arranged in parallel around the same axis. ,
Each planar coil constituting the planar coil group is formed by winding less than the number of turns of the power receiving coil,
In the planar coil group, a plurality of planar coils that allow current to flow from among the planar coils that constitute the planar coil group, and a connection terminal that can be selected by sandwiching the wires of other planar coils that are not selected. Is provided,
30. The electromagnetic induction coil according to claim 29, wherein the plurality of selected planar coils are connected in parallel.   34. The electromagnetic induction coil according to claim 32 or 33, wherein the element wire constituting the planar coil to be selected is provided with identification means for distinguishing from other planar coils. The power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
The planar coil group on the power receiving side is provided with a connection terminal capable of selecting a planar coil to be used for electromagnetic induction from the planar coil group. Electromagnetic induction coil.   36. The coil for electromagnetic induction according to claim 35, wherein the element wire constituting the planar coil to be selected is provided with identification means for distinguishing from other planar coils. The planar coil constituting the feeding coil is composed of two planar coils formed by winding two strands arranged in parallel around the same axis, and the two planar coils are connected in parallel. ,
The coil for electromagnetic induction according to claim 28, wherein the number of turns of each of the two planar coils is smaller than the number of turns of the power receiving coil. The feeding coil is composed of a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
Each planar coil constituting the planar coil group is wound less than the number of turns of the power receiving coil,
29. The electromagnetic induction according to claim 28, wherein the planar coil group is provided with a connection terminal capable of selecting a planar coil that allows current to flow from each planar coil constituting the planar coil group. Coil. The feeding coil is constituted by a planar coil group formed by winding at least four strands arranged in parallel around the same axis,
Each planar coil constituting the planar coil group is wound less than the number of turns of the power receiving coil,
In the planar coil group, a plurality of planar coils that allow current to flow from among the planar coils that constitute the planar coil group, and a connection terminal that can be selected by sandwiching the wires of other planar coils that are not selected. Is provided,
29. The electromagnetic induction coil according to claim 28, wherein the selected plurality of planar coils are connected in parallel.   40. The electromagnetic induction coil according to claim 38 or 39, wherein the element wire constituting the planar coil to be selected is provided with identification means for distinguishing from other planar coils. The power receiving coil is constituted by a planar coil group formed by winding a plurality of strands arranged in parallel around the same axis,
The said planar coil group is provided with the connection terminal which enables selection of the planar coil utilized for electromagnetic induction from each planar coil which comprises this planar coil group. 39. The electromagnetic induction coil according to 39.   42. The electromagnetic induction coil according to claim 41, wherein the wire constituting the planar coil to be selected is provided with identification means for distinguishing from other planar coils.   28. The electromagnetic induction coil according to claim 27, wherein the power feeding coil includes two planar coils, and the two planar coils are connected in series. The two planar coils are formed by winding two strands arranged in parallel around the same axis,
44. The electromagnetic induction coil according to claim 43, wherein innermost strands of each planar coil are connected to each other.

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