Contactless power supply system and power transmission device

Abstract

To provide a contactless power supply system and a power transmission device that can improve installation flexibility.SOLUTION: A contactless power supply system 1 is a system for supplying electric power in a non-contact manner to a load 4, and comprises: a power transmission device 2; and a power reception device 3. The power transmission device 2 comprises: a high-frequency power supply 21 that outputs power of a high frequency; a power transmission electrode 22 that transmits the power output from the high-frequency power supply 21; and a relay electrode 23 that receives and transmits the power transmitted from the power transmission electrode 22 in a non-contact manner by electric field coupling. The power reception device 3 comprises a power reception electrode 31 that receives the power transmitted from the relay electrode 23 in a non-contact manner by electric field coupling and supplies the received power to the load 4.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a non-contact power supply system that transmits power non-contact by an electric field coupling method, and a power transmission device used in the non-contact power supply system.

Background Art

[0002] In recent years, electric vehicles and electric vehicles that automatically operate unmanned have attracted attention, and various research and developments have been made. In order to popularize such electric vehicles and electric vehicles, problems such as the cost, weight of the mounted battery, the length of the power supply time, the difficulty of recycling, and the increase in human cost have become issues. As one of the methods for solving such problems, a technology for power supply without a person and non-contact is being studied.

[0003] As such a non-contact power supply method, for example, there are a space type transmission method, an electric field coupling method, and a magnetic field coupling method. In the space type transmission method, electromagnetic waves propagate between a power transmission antenna and a power reception antenna to transmit power non-contact. The space type transmission method has the characteristics that it can transmit over a long distance, while the power reception efficiency and the amount of power that can be handled are small.

[0004] In the electric field coupling method, power is transmitted non-contact by the electric field energy being transmitted through the space by a capacitor formed between a power transmission electrode and a power reception electrode. In the magnetic field coupling method, power is transmitted non-contact by the power transmission coil and the power reception coil performing an operation like a transformer.

[0005] The electric field coupling method and the magnetic field coupling method have the characteristics that the power reception range is a short distance compared to the space type transmission method, while the power reception efficiency and the amount of power are large. Therefore, it is attracting attention as a mainstream method for non-contact power supply to electric vehicles and electric vehicles. Among them, the electric field coupling method does not require laying of expensive coils like the magnetic field coupling method, so it can be realized at low cost and is suitable for non-contact power supply that requires power transmission equipment over a wide range (for example, Patent Documents 1 and 2).

Prior Art Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2016-63684 [Patent Document 2] Japanese Patent Publication No. 2017-163798 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] When supplying power to a vehicle using a non-contact power supply system based on electric field coupling, as shown in Patent Documents 1 and 2, the transmission line is buried in the road, and the high-frequency power supply is connected to the transmission line by wire. However, regardless of whether the high-frequency power supply is above or below the floor, connection work to the transmission line is required, which has problems such as limiting the structure of the transmission line and making it difficult to replace the high-frequency power supply.

[0008] This invention was made to solve the above-mentioned problems and aims to provide a contactless power supply system and power transmission device that can improve the degree of freedom in installation. [Means for solving the problem]

[0009] To achieve this objective, the contactless power supply system according to claim 1 provides a power supply to a load in a contactless manner, comprising: a power supply device comprising: a high-frequency power supply that outputs high-frequency power; a power supply electrode that transmits the power output from the high-frequency power supply; a relay electrode that receives and transmits the power transmitted from the power supply electrode in a contactless manner using an electric field coupling method without a resonant coil; and a power receiving device comprising: a power receiving electrode that receives the power transmitted from the relay electrode in a contactless manner using an electric field coupling method, and supplies the received power to the load. The relay electrode has one electrode plate that receives power from the power transmitting electrode using an electric field coupling method and transmits the received power to the power receiving electrode using an electric field coupling method. ru. The non-contact power supply system according to claim 2 supplies power to a load in a non-contact manner and comprises a power supply device comprising: a high-frequency power supply that outputs high-frequency power; a power supply electrode that transmits the power output from the high-frequency power supply; a relay electrode that receives and transmits power transmitted from the power supply electrode in a non-contact manner using an electric field coupling method without having a resonant coil; and a power receiving device comprising a power receiving electrode that receives power transmitted from the relay electrode in a non-contact manner using an electric field coupling method and supplies the received power to the load, wherein the relay electrode consists of a plurality of electrode plates that do not have a resonant coil and are not connected to each other by wiring, and at least a portion of the electrode plates are stacked facing each other, power transmitted from the power supply electrode is received by one of the electrode plates using an electric field coupling method, power is transmitted from another electrode plate to the power receiving electrode using an electric field coupling method, and power is transmitted and received between adjacent electrode plates in a non-contact manner using an electric field coupling method. The non-contact power supply system according to claim 3 supplies power to a load in a non-contact manner and comprises a power transmission device comprising: a high-frequency power supply that outputs high-frequency power; a power transmission electrode that transmits the power output from the high-frequency power supply; and a relay electrode that receives and transmits power transmitted from the power transmission electrode in a non-contact manner using an electric field coupling method without having a resonant coil; and a power receiving device comprising a power receiving electrode that receives power transmitted from the relay electrode in a non-contact manner using an electric field coupling method and supplies the received power to the load, wherein the relay electrode consists of a plurality of electrode plates without resonant coils that are not connected to each other by wiring, and at least a portion of the electrode plates are arranged in a series in a non-facing manner, and power transmitted from the power transmission electrode is received by one of the electrode plates using an electric field coupling method, power is transmitted from another electrode plate to the power receiving electrode using an electric field coupling method, and power is transmitted and received between adjacent electrode plates in a non-contact manner using an electric field coupling method.

[0010] Claim4 The contactless power supply system described is as described in claim 1 From one of 3 In the contactless power supply system described, the relay electrode is fixedly installed at a predetermined position.

[0011] Claim 5 The contactless power supply system described is as described in claim 1 From to one of 4 In the contactless power supply system described, the power transmission device includes a matching circuit for impedance matching.

[0014] The power transmission device according to claim 6 transmits power to a power receiving device that has a power receiving electrode to receive power and supplies the received power to a load, using an electric field coupling method in a non-contact manner, and comprises a high-frequency power supply that outputs high-frequency power, a power transmission electrode that transmits the power output from the high-frequency power supply, and a resonant coil. It consists of a single electrode plate, or a plurality of electrode plates that do not have a resonant coil and are not connected to each other by wiring. The system includes a relay electrode that receives and transmits power transmitted from the aforementioned power transmission electrode in a non-contact manner using an electric field coupling method. [Effects of the Invention]

[0015] According to the contactless power supply system of claim 1, in the power transmission device, the high-frequency power output from the high-frequency power supply is transmitted from the power transmission electrode. 、 Intermediate electrodes that do not have resonant coils On one electrode plate provided It is transmitted and received non-contact using an electric field coupling method. the relay electrode A single electrode plate is provided there The power received in that electrode plateIt is transmitted and received non - contact by the electric field coupling method from toward the power receiving electrode of the power receiving device. The power receiving device supplies the power received by its power receiving electrode to the load. In this way, since the transmission of power from the power transmitting electrode to the relay electrode that transmits power to the power receiving electrode of the power receiving device is performed non - contact by the electric field coupling method from the power transmitting electrode to the relay electrode, it is possible to suppress the installation position of the high - frequency power source from being restricted by the position of the relay electrode. In addition, non - contact power supply by the electric field coupling method that does not use a coil for resonance can suppress a small decrease in transmission efficiency even if there is a slight deviation in the positions of the electrodes that transmit and receive power. Therefore, there is an effect that the degree of freedom of installation can be improved. According to the contactless power supply system described in claim 2, in the power transmission device, high-frequency power output from a high-frequency power source is transmitted and received contactlessly from the transmitting electrode to a relay electrode that does not have a resonant coil, using an electric field coupling method. Then, the power received at the relay electrode is transmitted and received contactlessly from the relay electrode to the receiving electrode of the power receiving device using an electric field coupling method. The power receiving device supplies the power received by its receiving electrode to the load. Here, the relay electrode is provided with a plurality of electrode plates that do not have a resonant coil and are not connected to each other by wiring, and at least a portion of these electrode plates are stacked facing each other. Then, power transmitted from the transmitting electrode is received at one electrode plate using an electric field coupling method, and power is transmitted from another electrode plate to the receiving electrode using an electric field coupling method. Power is also transmitted and received contactlessly between adjacent electrode plates using an electric field coupling method. In this way, since the relay electrode is constructed by stacking at least some of several electrode plates, even when the location of the high-frequency power supply of the power transmission device and the location of the load are far apart, the power output from the high-frequency power supply can be transmitted to the receiving electrode via the multiple electrode plates and supplied to the load. Furthermore, since power is transmitted and received by an electric field coupling method that does not use resonant coils, the reduction in transmission efficiency can be kept to a minimum even if there is some misalignment of each electrode, as power is transmitted and received via multiple electrode plates. Therefore, this has the effect of improving the degree of flexibility in installation. According to the non-contact power supply system described in claim 3, in the power transmission device, high-frequency power output from a high-frequency power source is transmitted and received non-contact from the transmitting electrode to a relay electrode that does not have a resonant coil, using an electric field coupling method. Then, the power received at the relay electrode is transmitted and received non-contact from the relay electrode to the receiving electrode of the power receiving device using an electric field coupling method. The power receiving device supplies the power received by its receiving electrode to the load. Here, the relay electrode consists of a plurality of electrode plates that do not have a resonant coil and are not connected to each other by wiring, and at least a portion of the electrode plates are arranged in a series in a non-facing arrangement. Power transmitted from the transmitting electrode is received at one electrode plate using an electric field coupling method, and power is transmitted from another electrode plate to the receiving electrode using an electric field coupling method. Power is also transmitted and received non-contact between adjacent electrode plates using an electric field coupling method. In this way, by arranging at least some of the electrode plates in a cascaded manner in a non-facing configuration to form a relay electrode, even when the location of the high-frequency power supply of the power transmission device and the location of the load are far apart, the power output from the high-frequency power supply can be transmitted to the receiving electrode via the multiple electrode plates and supplied to the load. Furthermore, since power is transmitted and received using an electric field coupling method that does not use resonant coils, the reduction in transmission efficiency can be kept to a minimum even if there is some misalignment of each electrode, as power is transmitted and received via multiple electrode plates. Therefore, this has the effect of improving the flexibility of installation.

[0016] Claim 4 According to the non - contact power supply system described in claim From one of 3 In addition to the effects achieved by the contact power supply system described in claim 1, the following effects are achieved. That is, even when the relay electrode is provided fixed at a predetermined position, power output from the high - frequency power source is transmitted non - contact to the fixed relay electrode by the electric field coupling method. Thereby, it is possible to suppress the installation position of the high - frequency power source from being restricted by the position of the fixed relay electrode, so there is an effect that the degree of freedom of installation can be improved.

[0017] Claim 5 According to the non - contact power supply system described in claim From to one of 4 In addition to the effects achieved by the non - contact power supply system described in claim 1, the following effects are achieved. That is, impedance matching is performed by the matching circuit provided in the power transmitting device, so there is an effect that a small decrease in transmission efficiency can be suppressed.

[0020] According to the power transmitting device described in claim 6, the high - frequency power output from the high - frequency power source is from the power transmitting electrode to a relay electrode without a coil for resonance It is composed of a single electrode plate. relay electrode the electrode plate toward Alternatively, towards one electrode plate of a relay electrode, which is composed of multiple electrode plates that do not have resonant coils and are not connected to each other by wiring,It is transmitted and received non - contact by an electric - field coupling method. Moreover, the power received at the relay electrode is transmitted and received non - contact by an electric - field coupling method from the relay electrode of the power - transmitting device toward the power - receiving electrode. The power - receiving device supplies power received by its power - receiving electrode to the load. Thus, since the transmission of power to the relay electrode that transmits power to the power - receiving electrode of the power - receiving device is performed non - contact by an electric - field coupling method from the power - transmitting electrode toward the relay electrode, it is possible to suppress the installation position of the high - frequency power source from being restricted by the position of the relay electrode. Also, non - contact power supply by an electric - field coupling method that does not use a coil for resonance can suppress a small decrease in transmission efficiency even if there is a slight deviation in the positions of the electrodes that transmit and receive power. Therefore, there is an effect that the degree of freedom in installation can be improved.

Brief Description of the Drawings

[0021] [Figure 1] It is a schematic front view of a non - contact power - supply system according to the first embodiment of the present invention. [Figure 2] (a) is an equivalent circuit diagram used for circuit simulation of the non - contact power - supply system, and (b) is a diagram showing S - parameter characteristics with respect to the frequency of power obtained by the circuit simulation. [Figure 3] (a) is a photograph of the non - contact power - supply system constructed for verification, and (b) is a diagram showing DC - DC conversion efficiency characteristics with respect to the load resistance obtained by a verification experiment. [Figure 4] It is a schematic front view of a non - contact power - supply system according to the second embodiment of the present invention. [Figure 5] It is a schematic front view of a non - contact power - supply system according to the third embodiment of the present invention. [Figure 6] It is a schematic front view of a non - contact power - supply system according to the fourth embodiment of the present invention. [Figure 7] It is a schematic front view of a non - contact power - supply system according to the fifth embodiment of the present invention. [Figure 8] It is a schematic front view of a non - contact power - supply system according to the sixth embodiment of the present invention. [Modes for carrying out the invention]

[0022] Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. The embodiments described below are all preferred specific examples of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement positions of components, and connection configurations shown in the following embodiments are examples and are not intended to limit the present invention. Accordingly, among the components in the following embodiments, those not described in the independent claims representing the highest-level concept of the present invention will be described as optional components. Furthermore, in each figure, substantially identical components are denoted by the same reference numerals, and redundant explanations are omitted or simplified.

[0023] (First Embodiment) First, with reference to Figures 1 to 3, the schematic configuration of the contactless power supply system 1 and power transmission device 2 according to the first embodiment of the present invention will be described. Figure 1 is a schematic front view of the contactless power supply system 1.

[0024] The contactless power supply system 1 is a system that supplies power to a load 4 wirelessly and consists of a power transmission device 2 and a power receiving device 3. The load 4 can be, for example, a battery that stores the supplied power, or something that operates using the supplied power (for example, a motor).

[0025] The power transmission device 2 is a device that transmits (transmits) power to the power receiving device 3 to which the load 4 is connected, using an electric field coupling method in a contactless manner, and has at least a high-frequency power supply 21, a power transmission electrode 22, and a relay electrode 23.

[0026] The high-frequency power supply 21 is a high-frequency inverter that generates and outputs high-frequency power, and the power transmission electrode 22 is connected by wire via a matching circuit (not shown). The matching circuit is a circuit that matches the output impedance of the high-frequency power supply 21 with the input impedance to the high-frequency power supply 21.

[0027] Furthermore, the matching circuit and / or the power transmission electrode 22 may be built into the high-frequency power supply 21, or the high-frequency power supply 21 and the matching circuit and / or power transmission electrode 22 may be configured as a single unit. Also, if the output impedance of the high-frequency power supply 21 and the input impedance to the high-frequency power supply 21 are matched, the matching circuit can be omitted.

[0028] The power transmission electrode 22 is provided to form an electric field coupler (capacitor) with the relay electrode 23, and is an electrode for transmitting power output from the high-frequency power supply 21 to the relay electrode 23.

[0029] The relay electrode 23 is fixedly installed embedded in the floor 10 (or under the road) and is an electrode that receives power transmitted from the power transmission electrode 22 in a non-contact manner using an electric field coupling method by an electric field coupler (capacitor) formed between the power transmission electrode 22 and the relay electrode 23. Furthermore, as will be described later, the relay electrode 23 is also an electrode that transmits power (transmits power) to the power receiving electrode 31 in a non-contact manner using an electric field coupling method by an electric field coupler (capacitor) formed between the relay electrode 23 and the power receiving electrode 31.

[0030] In the contactless power supply system 1 according to the first embodiment, the high-frequency power supply 21 and the power transmission electrode 22 are located above the floor (or ground) surface, rather than in the same underfloor area 10 as the relay electrode 23.

[0031] Next, the power receiving device 3 is a device that receives power transmitted from the power transmitting device 2 and supplies the received power to the load 4, and is installed above the floor surface together with the load 4. This power receiving device 3 has at least a power receiving electrode 31. In addition, the power receiving device 3 and the load 4 may be configured as a single unit, such as by having the power receiving device 3 built into the load 4.

[0032] The receiving electrode 31 is an electrode provided to form an electric field coupler (capacitor) with the relay electrode 23. Power transmitted from the relay electrode 23 is received (received) non-contact by electric field coupling through the electric field coupler (capacitor) formed between the relay electrode 23 and the receiving electrode 31. The receiving electrode 31 is wired to the load 4 via a matching circuit (not shown) and, if necessary, a rectifier circuit (not shown).

[0033] Here, the matching circuit is a circuit that controls the output impedance to load 4 and the input impedance of load 4. The rectifier circuit is a circuit that rectifies the high-frequency power output from the power receiving electrode 31 into DC. For example, if load 4 is a DC motor, the DC motor is driven by the power rectified into DC by the rectifier circuit. If load 4 is a battery, the power rectified into DC by the rectifier circuit is supplied to the battery, and the battery is charged.

[0034] Next, the operation of the contactless power supply system 1 configured as described above will be explained. In the contactless power supply system 1, when high-frequency power is generated by the high-frequency power supply 21 in the power transmission device 2, that power is output to the power transmission electrode 22 via a matching circuit (not shown). The power output to the power transmission electrode 22 is transmitted (powered) to the relay electrode 23 by electric field coupling in a contactless manner.

[0035] When the relay electrode 23 receives power transmitted from the power transmission electrode 22, it transmits the received power to the power receiving electrode 31 of the power receiving device 3 using an electric field coupling method in a non-contact manner. The power receiving device 3 receives the power transmitted from the relay electrode 23 via the power receiving electrode 31. The power receiving device 3 then supplies the power received by the power receiving electrode 31 to the load 4.

[0036] Here, with reference to Figures 2 and 3, the power transmission efficiency of the contactless power supply system 1 will be explained. First, in Figure 2, the power transmission efficiency of the contactless power supply system 1 was analyzed by circuit simulation using the equivalent circuit of the contactless power supply system 1. Here, Figure 2(a) is the equivalent circuit diagram used in the circuit simulation, and Figure 2(b) is a diagram showing the S-parameter characteristics of the power with respect to frequency obtained from the circuit simulation.

[0037] In the circuit diagram used for the circuit simulation of the contactless power supply system 1, as shown in Figure 2(a), the output impedance of the high-frequency power supply 21 was set to a 50Ω resistor, and the load 4 was set to a 50Ω resistor. In this circuit diagram, the matching circuit on the power transmission device 2 side, the field coupler consisting of the power transmission electrode 22 and the relay electrode 23, the field coupler consisting of the relay electrode 23 and the power receiving electrode 31, and the matching circuit on the power receiving device 3 side were connected in series between the high-frequency power supply 21 and the load 4.

[0038] In the matching circuit on the power transmission device 2 side, a series-connected inductor L1 (6.86 μH) and resistor R1 (4 Ω) are connected in parallel with the high-frequency power supply 21. Furthermore, on the downstream side of this parallel connection (the field coupler side formed by the power transmission electrode 22 and the relay electrode 23), at one end of the high-frequency power supply 21, an inductor L2 (6.93 μH) and resistor R2 (4 Ω) are connected in series. The values ​​in parentheses are the inductance or resistance values ​​of each element used in the circuit simulation (the same applies hereafter in the explanation of Figure 2(a)).

[0039] In the electric field coupler consisting of a transmitting electrode 22 and a relay electrode 23, 20pF capacitors C1 and C3 were connected in parallel with the high-frequency power supply 21 as self-capacitance, and a 60pF capacitor C2 was connected in series between the connection point of capacitors C1 and C3 on one end of the high-frequency power supply 21 as mutual capacitance.

[0040] In the electric field coupler consisting of the relay electrode 23 and the receiving electrode 31, 20pF capacitors C4 and C6 were connected in parallel with the high-frequency power supply 21 as self-capacitance, and a 60pF capacitor C5 was connected in series between the connection point of capacitors C4 and C6 on one end of the high-frequency power supply 21 as mutual capacitance.

[0041] In the matching circuit on the power receiving device 3 side, an inductor L4 (10.73 μH) and a resistor R4 (4 Ω) connected in series were connected in parallel with the high-frequency power supply 21. Furthermore, on the upstream side of this parallel connection (the electric field coupler side formed by the relay electrode 23 and the power receiving electrode 31), on one end of the high-frequency power supply 21, an inductor L3 (9.68 μH) and a resistor R3 (4 Ω) were connected in series.

[0042] As a result of circuit simulation using the equivalent circuit shown in Figure 2(a), the frequency characteristics of the S-parameters were obtained as shown in Figure 2(b). Specifically, S11, which represents the power reflection loss on the high-frequency power supply 21 side, and S21, which represents the power insertion loss (transmission rate) from the high-frequency power supply 21 to the load 4, show the best values ​​around a frequency of 6.78 MHz. In other words, by setting the power frequency to 6.78 MHz, it is possible to keep the power reflection loss to the lowest level while achieving a good power transmission rate of 90%.

[0043] 6.78MHz is a type of ISM band frequency intended for contactless power transmission. The results of this circuit simulation show that, instead of the conventional configuration in which power output from the high-frequency power supply 21 is supplied to the relay electrode 23 via a wire, power can be transmitted contactlessly from the transmitting electrode 22 to the relay electrode 23 using an electric field coupling method, and the power can still be efficiently transmitted to the load 4.

[0044] Next, with reference to Figure 3, the demonstration of the contactless power supply system 1 according to the first embodiment will be described. Figure 3(a) is a photograph of the contactless power supply system 1 actually constructed for the demonstration, and Figure 3(b) is a diagram showing the DC-DC conversion efficiency characteristics with respect to load resistance obtained from the demonstration experiment.

[0045] As shown in Figure 3(a), in this demonstration, a contactless power supply system 1 was constructed in which power is supplied via a wire from a high-frequency power supply 21 to a transmitting electrode 22, power is transmitted from the transmitting electrode 22 to a relay electrode 23 via an electric field coupling method without contact, power is transmitted from the relay electrode 23 to a receiving electrode 31 via an electric field coupling method without contact, and the power received by the receiving electrode 31 is supplied to the load 4 via a wire.

[0046] Furthermore, in this demonstration, an electronic load was used for load 4, and the DC-DC conversion efficiency from the high-frequency power supply 21 to load 4 was measured while varying the resistance value from 20Ω to 1000Ω. As a result, as shown in Figure 3(b), the DC-DC conversion efficiency was 60% or more when the resistance value of load 4 was between 50Ω and 100Ω.

[0047] In the non-contact power supply system 1, a load of 50Ω is generally used as the load 4. Therefore, instead of the conventional configuration in which power output from the high-frequency power supply 21 is supplied to the relay electrode 23 by wire, power can be transmitted non-contact from the transmitting electrode 22 to the relay electrode 23 using an electric field coupling method, and the power can be efficiently transmitted to the load 4.

[0048] The contactless power supply system 1 and power transmission device 2 according to the first embodiment described above provide the following effects and advantages.

[0049] (a) In the power transmission device 2, high-frequency power output from the high-frequency power supply 21 is transmitted and received non-contact from the power transmission electrode 22 to the relay electrode 23 using an electric field coupling method. Then, the power received at the relay electrode 23 is transmitted and received non-contact from the relay electrode 23 to the power receiving electrode 31 of the power receiving device 3 using an electric field coupling method. The power receiving device 3 supplies the power received by its power receiving electrode 31 to the load 4.

[0050] Thus, power is supplied to the relay electrode 23, which transmits power to the receiving electrode 31 of the power receiving device 3, not via a wired connection from the high-frequency power supply 21, but non-contact via electric field coupling from the transmitting electrode 22 to the relay electrode 23. Even when power is supplied to the relay electrode 23 in this manner, power can be efficiently transmitted to the load 4. Furthermore, by supplying power from the transmitting electrode 22 to the relay electrode 23 non-contact via electric field coupling, the installation position of the high-frequency power supply 21 is not restricted by the position of the relay electrode 23.

[0051] Furthermore, in contactless power supply using magnetic field coupling with coils, it is known that even a slight shift in the position of the coil can drastically reduce the power transmission efficiency. In contrast, contactless power supply using electric field coupling can minimize the decrease in transmission efficiency even if there is a slight misalignment between the electrodes that transmit and receive power.

[0052] Based on the above, the contactless power supply system 1 and power transmission device 2 according to the first embodiment can improve the degree of flexibility in their installation.

[0053] (b) Even when the relay electrode 23 is fixed to the underfloor 10, the power output from the high-frequency power supply 21 is transmitted to the fixed relay electrode 23 non-contact by electric field coupling. This prevents the installation position of the high-frequency power supply 21 from being restricted by the position of the fixed relay electrode 23, thereby improving the degree of freedom in installation.

[0054] (c) Even when the relay electrode 23 is buried in the underfloor 10, power output from the high-frequency power supply 21 is transmitted to the buried relay electrode 23 non-contact by electric field coupling. This prevents the installation location of the high-frequency power supply 21 from being restricted by the location of the buried relay electrode 23. Furthermore, even if the location of the relay electrode 23 is difficult to ascertain due to burial, and there is a slight misalignment between the electrodes of the power transmission electrode 22 and the relay electrode 23, the decrease in transmission efficiency can be kept to a minimum. Thus, the degree of freedom in installation can be improved. In addition, since there is no need to perform construction work such as digging up the underfloor 10 to connect wiring from the high-frequency power supply 21 to the buried relay electrode 23, the degree of freedom in installation can be further improved, and the increase in installation costs can be suppressed.

[0055] (d) Since the high-frequency power supply 21 and the power transmission electrode 22 can be installed above the floor surface without being buried in the underfloor 10, the limitation of their installation to the relay electrode 23 buried in the underfloor 10 can be further reduced. Therefore, the degree of freedom in installation can be further increased. In addition, since the high-frequency power supply 21 and the power transmission electrode 22 are installed above the floor surface, maintenance and replacement of the high-frequency power supply 21 and the power transmission electrode 22 can be easily performed. Furthermore, since there is no need for construction work to bury the high-frequency power supply 21 and the power transmission electrode 22 in the underfloor 10, such as digging up the underfloor 10, the increase in installation costs can also be suppressed.

[0056] (Second Embodiment) Next, with reference to Figure 4, the schematic configuration of the contactless power supply system 1 and power transmission device 2 according to the second embodiment of the present invention will be described. Figure 4 is a schematic front view of the contactless power supply system 1. In Figure 4, the same reference numerals are used for components identical to those of the contactless power supply system 1 and power transmission device 2 according to the first embodiment, and their explanation is omitted here.

[0057] The difference between the contactless power supply system 1 and power transmission device 2 according to the second embodiment and the contactless power supply system 1 and power transmission device 2 according to the first embodiment is the installation location of the high-frequency power supply 21 and power transmission electrode 22 of the power transmission device 2. That is, in the first embodiment, the high-frequency power supply 21 and power transmission electrode 22 were installed above the floor surface (or road), but in the second embodiment, the high-frequency power supply 21 and power transmission electrode 22 are buried under the floor 10 (or under the road). The other configurations are the same as in the first embodiment.

[0058] In the non-contact power supply system 1 and power transmission device 2 according to the second embodiment, although the high-frequency power supply 21 and power transmission electrode 22 are buried under the floor 10 (or under the road), the power supply to the relay electrode 23 that transmits power to the power receiving electrode 31 of the power receiving device 3 is not done via a wire from the high-frequency power supply 21, but rather via a non-contact electric field coupling method from the power transmission electrode 22 to the relay electrode 23. Therefore, the installation position of the high-frequency power supply 21 is not restricted by the position of the relay electrode 23. Thus, the degree of freedom in installation can be improved.

[0059] Furthermore, the contactless power supply system 1 and power transmission device 2 according to the second embodiment have the same configuration as the contactless power supply system 1 and power transmission device 2 according to the first embodiment and achieve the same effects.

[0060] (Third embodiment) Next, with reference to Figure 5, the schematic configuration of the contactless power supply system 1 and power transmission device 2 according to the third embodiment of the present invention will be described. Figure 5 is a schematic front view of the contactless power supply system 1. In Figure 5, the same reference numerals are used for components identical to those of the contactless power supply system 1 and power transmission device 2 according to the first and second embodiments, and their explanation is omitted here.

[0061] The difference between the contactless power supply system 1 and power transmission device 2 according to the third embodiment and the contactless power supply system 1 and power transmission device 2 according to the second embodiment lies in the configuration of the relay electrode 23. Specifically, in the second embodiment, the relay electrode 23 is composed of one electrode plate, whereas in the third embodiment, it is composed of two electrode plates, a first relay electrode 231 and a second relay electrode 232, which are stacked facing each other. A field coupler (capacitor) is formed between the first relay electrode 231 and the second relay electrode 232. The relay electrode of the present invention is composed of this first relay electrode 231 and the second relay electrode 232. The other configurations are the same as in the second embodiment.

[0062] The first relay electrode 231 receives power transmitted from the power transmission electrode 22 via an electric field coupling method in a non-contact manner, and transmits the received power to the second relay electrode 232 via an electric field coupling method in a non-contact manner. The second relay electrode 232 also receives power transmitted from the first relay electrode 231 via an electric field coupling method in a non-contact manner, and transmits the received power to the power receiving electrode 31 of the power receiving device 3 via an electric field coupling method in a non-contact manner.

[0063] As described above, in the non-contact power supply system 1 and power transmission device 2 according to the third embodiment, the relay electrode is constructed by stacking a first relay electrode 231 and a second relay electrode 232 with a plurality of electrode plates. Therefore, even if the location of the high-frequency power supply 21 of the power transmission device 2 and the location of the load 4 are far apart, the power output from the high-frequency power supply 21 can be transmitted to the power receiving electrode 31 via the plurality of electrode plates (first relay electrode 231, second relay electrode 232) and power can be supplied to the load 4. Furthermore, since power is transmitted and received by an electric field coupling method, the transmission and reception of power is performed via the plurality of electrode plates (first relay electrode 231, second relay electrode 232), so even if there is some misalignment of each electrode, the decrease in transmission efficiency can be kept to a minimum. Thus, the degree of freedom in installation can be improved.

[0064] Furthermore, the contactless power supply system 1 and power transmission device 2 according to the third embodiment have the same configuration as the contactless power supply system 1 and power transmission device 2 according to the first and second embodiments, and thus achieve the same effects.

[0065] (Fourth Embodiment) Next, with reference to Figure 6, the schematic configuration of the non-contact power supply system 1 and power transmission device 2 according to the fourth embodiment of the present invention will be described. Figure 6 is a schematic front view of the non-contact power supply system 1. In Figure 6, the same reference numerals are used for components identical to those of the non-contact power supply system 1 and power transmission device 2 according to the first to third embodiments, and their explanation is omitted here.

[0066] The difference between the non-contact power supply system 1 and power transmission device 2 according to the fourth embodiment and the non-contact power supply system 1 and power transmission device 2 according to the first embodiment lies in the configuration of the relay electrode 23. Specifically, in the first embodiment, the relay electrode 23 is composed of one electrode plate, whereas in the fourth embodiment, it is composed of two electrode plates, a first relay electrode 231 and a second relay electrode 232, which are arranged in a cascaded manner in a non-facing configuration. An electric field coupler is formed between the first relay electrode 231 and the second relay electrode 232. The relay electrode of the present invention is composed of the first relay electrode 231 and the second relay electrode 232. The other configurations are the same as in the first embodiment.

[0067] The first relay electrode 231 receives power transmitted from the power transmission electrode 22 via an electric field coupling method in a non-contact manner, and transmits the received power to the second relay electrode 232 via an electric field coupling method in a non-contact manner. The second relay electrode 232 also receives power transmitted from the first relay electrode 231 via an electric field coupling method in a non-contact manner, and transmits the received power to the power receiving electrode 31 of the power receiving device 3 via an electric field coupling method in a non-contact manner.

[0068] As described above, in the non-contact power supply system 1 and power transmission device 2 according to the fourth embodiment, the relay electrode is configured with a first relay electrode 231 and a second relay electrode 232 and a plurality of electrode plates arranged in a series. Therefore, even if the position of the high-frequency power supply 21 of the power transmission device 2 and the position of the receiving electrode 31 of the power receiving device 3 are far apart, or even if the position of the high-frequency power supply 21 of the power transmission device 2 and the position of the load 4 are far apart, the power output from the high-frequency power supply 21 can be transmitted to the receiving electrode 31 via the plurality of electrode plates (first relay electrode 231, second relay electrode 232) and power can be supplied to the load 4. Furthermore, since power is transmitted and received by electric field coupling, the transmission and reception of power is performed via the plurality of electrode plates (first relay electrode 231, second relay electrode 232), so even if there is some misalignment of each electrode, the decrease in transmission efficiency can be kept to a minimum. Thus, the degree of freedom in installation can be improved.

[0069] Furthermore, the contactless power supply system 1 and power transmission device 2 according to the fourth embodiment have the same configuration as the contactless power supply system 1 and power transmission device 2 according to the first to third embodiments and achieve the same effects.

[0070] (Fifth embodiment) Next, with reference to Figure 7, the schematic configuration of the contactless power supply system 1 and power transmission device 2 according to the fifth embodiment of the present invention will be described. Figure 7 is a schematic front view of the contactless power supply system 1. In Figure 7, the same reference numerals are used for components identical to those of the contactless power supply system 1 and power transmission device 2 according to the first to fourth embodiments, and their explanation is omitted here.

[0071] The difference between the contactless power supply system 1 and power transmission device 2 according to the fifth embodiment and the contactless power supply system 1 and power transmission device 2 according to the first embodiment lies in their installation location. In the first embodiment, the high-frequency power supply 21 and power transmission electrode 22 of the power transmission device 2 were installed above the floor surface, the relay electrode 23 of the power transmission device 2 was embedded in the space below the floor 10, and the power receiving device 3 and load 4 were installed above the high-frequency power supply 21 and power transmission electrode 22 of the power transmission device 2. In contrast, in the fifth embodiment, the relay electrode 23 is embedded in the ceiling 11, the high-frequency power supply 21 and power transmission electrode 22 are installed in the space above the ceiling, and the power receiving device 3 and load 4 are installed in a room or the like below the ceiling 11. Note that the high-frequency power supply 21 and power transmission electrode 22 may be installed in a room or the like below the ceiling 11 instead of in the space above the ceiling.

[0072] In this way, instead of supplying power to the relay electrode 23, which transmits power to the receiving electrode 31 of the power receiving device 3, via a wired connection from the high-frequency power supply 21, power is supplied from the transmitting electrode 22 to the relay electrode 23 via an electric field coupling method in a non-contact manner. For example, the relay electrode 23 can be embedded in the ceiling 11, while increasing the flexibility in the placement of the high-frequency power supply 21, the transmitting electrode 22, the power receiving device 3, and the load 4. Thus, the flexibility of installation can be improved.

[0073] (Sixth Embodiment) Next, with reference to Figure 8, the schematic configuration of the contactless power supply system 1 and power transmission device 2 according to the sixth embodiment of the present invention will be described. Figure 8 is a schematic front view of the contactless power supply system 1. In Figure 8, the same reference numerals are used for components identical to those of the contactless power supply system 1 and power transmission device 2 according to the first to fifth embodiments, and their explanation is omitted here.

[0074] The difference between the contactless power supply system 1 and power transmission device 2 according to the sixth embodiment and the contactless power supply system 1 and power transmission device 2 according to the first embodiment is their installation location. In the first embodiment, the high-frequency power supply 21 and power transmission electrode 22 of the power transmission device 2 were installed above the floor surface, the relay electrode 23 of the power transmission device 2 was embedded in the floor 10, and the power receiving device 3 and load 4 were installed above the high-frequency power supply 21 and power transmission electrode 22 of the power transmission device 2. In contrast, in the sixth embodiment, the relay electrode 23 is embedded in the wall 12, the high-frequency power supply 21 and power transmission electrode 22 are installed in a room partitioned by the wall 12, and the power receiving device 3 and load 4 are also installed in the same room. The high-frequency power supply 21 and power transmission electrode 22 may also be installed in an adjacent room partitioned by the wall 12.

[0075] In this way, instead of supplying power to the relay electrode 23, which transmits power to the receiving electrode 31 of the power receiving device 3, via a wired connection from the high-frequency power supply 21, power is supplied from the transmitting electrode 22 to the relay electrode 23 using an electric field coupling method in a non-contact manner. For example, the relay electrode 23 can be embedded in the wall 12, while increasing the flexibility in the placement of the high-frequency power supply 21, the transmitting electrode 22, the power receiving device 3, and the load 4. Thus, the flexibility of installation can be improved.

[0076] Although the present invention has been described above based on embodiments, it can be easily inferred that the present invention is not limited in any way to the above embodiments, and that various improvements and modifications are possible without departing from the spirit of the present invention.

[0077] For example, each embodiment may be configured by modifying it by adding or replacing some or more parts of the configuration of other embodiments with those of other embodiments. Furthermore, the numerical values ​​given in the above embodiments are merely examples, and it is naturally possible to use other numerical values.

[0078] For example, in the third and fourth embodiments, the case in which the relay electrode is composed of two electrode plates was described, but it may also be composed of three or more electrode plates. When composed of three or more electrode plates, power transmitted from the power transmitting electrode 22 is received non-contact by electric field coupling at one electrode plate, power is transmitted non-contact by electric field coupling from another electrode plate to the power receiving electrode 31, and power is transmitted and received non-contact by electric field coupling between adjacent electrode plates. The more electrode plates there are, the greater the flexibility of installation, even when the location of the high-frequency power supply 21 of the power transmission device 2 and the location of the load 4 are further apart, as power output from the high-frequency power supply 21 can be transmitted to the power receiving electrode 31 via multiple electrode plates and power can be supplied to the load 4.

[0079] Furthermore, by combining the third and fourth embodiments, a relay electrode may be constructed by stacking some of the electrode plates of three or more electrode plates facing each other, and arranging the remaining electrode plates in a longitudinal row so as not facing each other. This allows for more flexible setting of the position of the high-frequency power supply 21 of the power transmission device 2 and the position of the load 4, thereby further improving the flexibility of installation. [Explanation of Symbols]

[0080] 1. Contactless power supply system 2 Power transmission equipment 3. Power receiving device 4 load 21 High frequency power supply 22 Power transmission electrodes 23 Relay electrodes 31 Receiving electrode

Claims

1. A contactless power supply system that supplies power to a load without contact, A power transmission device comprising: a high-frequency power supply that outputs high-frequency power; a power transmission electrode that transmits the power output from the high-frequency power supply; and a relay electrode that receives and transmits the power transmitted from the power transmission electrode in a non-contact manner using an electric field coupling method without having a resonant coil. A power receiving device comprising a power receiving electrode that receives power transmitted from the relay electrode in a non-contact manner using an electric field coupling method, and which supplies the received power to the load, Equipped with, The contactless power supply system is characterized in that the relay electrode has one electrode plate that receives power from the power transmitting electrode using an electric field coupling method and transmits the received power to the power receiving electrode using an electric field coupling method.

2. A non-contact power supply system that supplies power to a load without contact, A power transmission device comprising: a high-frequency power supply that outputs high-frequency power; a power transmission electrode that transmits the power output from the high-frequency power supply; and a relay electrode that receives and transmits the power transmitted from the power transmission electrode in a non-contact manner using an electric field coupling method without having a resonant coil. A power receiving device comprising a power receiving electrode that receives power transmitted from the relay electrode in a non-contact manner using an electric field coupling method, and which supplies the received power to the load, Equipped with, The aforementioned relay electrode consists of multiple electrode plates, each without a resonant coil, that are not connected to one another by wiring, and at least a portion of these electrode plates are stacked facing each other. In one of the electrode plates, the power transmitted from the power transmitting electrode is received by an electric field coupling method. Power is transmitted from one of the electrode plates towards the receiving electrode using an electric field coupling method. A non-contact power supply system characterized in that power is transmitted and received between adjacent electrode plates in a non-contact manner by electric field coupling.

3. A non-contact power supply system that supplies power to a load without contact, A power transmission device comprising: a high-frequency power supply that outputs high-frequency power; a power transmission electrode that transmits the power output from the high-frequency power supply; and a relay electrode that receives and transmits the power transmitted from the power transmission electrode in a non-contact manner using an electric field coupling method without having a resonant coil. A power receiving device comprising a power receiving electrode that receives power transmitted from the relay electrode in a non-contact manner using an electric field coupling method, and which supplies the received power to the load, Equipped with, The aforementioned relay electrode consists of multiple electrode plates, each without a resonant coil, that are not connected to one another by wiring, and at least a portion of these electrode plates are arranged in a longitudinal sequence in a non-facing arrangement. In one of the electrode plates, the power transmitted from the power transmitting electrode is received by an electric field coupling method. Power is transmitted from one of the electrode plates towards the receiving electrode using an electric field coupling method. A non-contact power supply system characterized in that power is transmitted and received between adjacent electrode plates in a non-contact manner by electric field coupling.

4. The contactless power supply system according to any one of claims 1 to 3, characterized in that the relay electrode is fixedly provided at a predetermined position.

5. The contactless power supply system according to any one of claims 1 to 4, characterized in that the power transmission device includes a matching circuit for impedance matching.

6. A power transmission device that transmits power to a power receiving device equipped with power receiving electrodes that receive power and supplies the received power to a load, using an electric field coupling method in a non-contact manner, A high-frequency power supply that outputs high-frequency power, A power transmission electrode that transmits the power output from the high-frequency power supply, A power transmission device comprising a relay electrode which consists of a single electrode plate without a resonant coil, or a plurality of electrode plates without a resonant coil and not connected to each other by wiring, and which receives and transmits power transmitted from the power transmission electrode in a non-contact manner using an electric field coupling method.

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