Non-contact power supply device

Abstract

To provide a non-contact power supply system in which a difference in power supply efficiency between a plurality of power transmission devices is reduced.SOLUTION: A non-contact power supply device 10 that performs non-contact power supply to a power receiving device 80 includes a DC power supply device 20, a DC wiring 51 that transmits output power of the DC power supply device, at least one DC / AC conversion device 30 that is connected to the DC wiring, an AC wiring 52 that transmits output power of the DC / AC conversion device, and at least one power transmitting device 40 that is connected to the AC wiring, and rated power of the DC power supply device is larger than rated power of the DC / AC conversion device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a contactless power supply device. [Background technology]

[0002] Patent Document 1 discloses a contactless power supply system including a high-frequency power supply device and a plurality of power transmission units connected to the high-frequency power supply device via switches, each of which is connected in parallel to the high-frequency power supply device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-51074 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned non-contact power supply device, when the number of power transmission units increases, the difference in length of the wiring connecting the high frequency power supply device and the power transmission unit increases between the power transmission unit close to the high frequency power supply device and the power transmission unit far from the high frequency power supply device. The greater the difference in the wiring length, the greater the difference in parasitic components such as parasitic inductance of the wiring. Therefore, there is a risk of a difference in power supply efficiency occurring between the power transmission unit close to the high frequency power supply device and the power transmission unit far from the high frequency power supply device. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] According to one embodiment of the present disclosure, there is provided a contactless power supply device (10, 210-710) that supplies power contactlessly to a power receiving device (80). The contactless power supply device includes a DC power supply device (20), a DC wiring (51) that transmits output power of the DC power supply device, at least one DC / AC conversion device (30, 730) connected to the DC wiring, an AC wiring (52) that transmits output power of the DC / AC conversion device, and at least one power transmission device (40, 840, 940) connected to the AC wiring, and the rated power of the DC power supply device is greater than the rated power of the DC / AC conversion device.

[0007] According to this embodiment, since the rated power of the DC power supply is larger than the rated power of the DC / AC conversion device, when a power transmission device is added, a new DC / AC conversion device can be added and connected to the DC power supply device, and the power transmission device can be connected to the added DC / AC conversion device. When a plurality of power transmission devices are connected to a DC power supply device, the range for laying the power wiring from the DC power supply device to the power transmission device is divided into a range for laying the DC wiring and a range for laying the AC wiring, so that the length of the AC wiring can be shortened compared to the case where AC wiring is laid from one DC / AC conversion device to all the power transmission devices. Therefore, even when a plurality of power transmission devices are arranged, the difference in distance between the DC / AC conversion device and each power transmission device can be made small, so that the difference in power supply efficiency caused by the difference in the length of the AC wiring can be made less likely to occur. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a non-contact power supply device according to a first embodiment. [Diagram 2] FIG. 1 is a circuit diagram of a non-contact power supply device according to a first embodiment. [Diagram 3] FIG. 11 is a schematic configuration diagram of a non-contact power supply device according to a second embodiment. [Figure 4] FIG. 11 is a circuit diagram of a non-contact power supply device according to a third embodiment. [Diagram 5] FIG. 11 is a diagram showing an output waveform of an inverter according to a third embodiment. [Figure 6]FIG. 13 is a schematic configuration diagram of a non-contact power supply device according to a fourth embodiment. [Figure 7] FIG. 13 is a schematic configuration diagram of a non-contact power supply device according to a fifth embodiment. [Figure 8] FIG. 13 is a circuit diagram of a non-contact power supply device according to a seventh embodiment. [Figure 9] FIG. 13 is a circuit diagram of a non-contact power supply device according to an eighth embodiment. [Figure 10] FIG. 13 is a circuit diagram of a non-contact power supply device according to a ninth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A. First embodiment: A1. Configuration of the wireless power supply system: As shown in Fig. 1, the contactless power supply device 10 includes a direct current power supply device 20, a plurality of DC / AC conversion devices 30, a plurality of power transmission devices 40, DC wiring 51, 51, and AC wiring 52, 52. In this embodiment, the plurality of power transmission devices 40 are buried under a road. The power transmission device 40 contactlessly supplies power to a power receiving device 80 (Fig. 9) mounted on a vehicle as a mobile body traveling on a road while the vehicle is traveling. Here, "while traveling" includes a case where the vehicle is moving and a case where the vehicle is stopped while waiting for a traffic light or the like. The vehicle is configured as, for example, an electric vehicle or a hybrid vehicle.

[0010] The moving body on which the power receiving device 80 is mounted is not limited to a vehicle traveling on a road, and may be, for example, an AGV (automated guided vehicle) or a traveling robot. The power transmitting device 40 may be installed not only under the road, but also on a sidewalk or parking lot adjacent to the road, or on a route on which the AGV travels. The power transmitting device 40 may be provided not only on a road or route that is approximately parallel to the ground, but also on a side surface that is approximately perpendicular to the ground. The device on which the power receiving device 80 is mounted may be a fixed device, not a moving body.

[0011] The DC power supply 20 has power supply input terminals 21, 21 and power supply output terminals 22, 22. The DC / AC conversion device 30 has input terminals 31, 31 and output terminals 32, 32. The power transmission device 40 has power transmission device terminals 41, 41. DC wiring 51, 51 transmits the output power of the DC power supply 20. AC wiring 52, 52 transmits the output power of the DC / AC conversion device 30.

[0012] The power supply input terminals 21, 21 of the DC power supply device 20 are connected to each of the two output terminals of the GPS power system by two power wirings. The DC power supply device 20 is supplied with AC power from the GPS power system via the two power wirings. The DC power supply device 20 converts the AC power to DC power and outputs the converted DC power from the power supply output terminals 22, 22. The frequency of the output power of the GPS power system is, for example, 60 Hz, and the voltage is, for example, 200 V. The output voltage of the DC power supply device 20 is, for example, 400 V. Note that the output power of the GPS power system and the voltage value of the output power of the DC power supply device 20 are not limited to those described above.

[0013] Each of the multiple DC / AC converters 30 is connected in parallel to the DC power supply device 20. Specifically, each of the power output terminals 22, 22 of the DC power supply device 20 is connected to each of the input terminals 31, 31 of the nearest DC / AC converter 30 among the multiple DC / AC converters 30 that is closest to the DC power supply device 20 by each of the DC wirings 51, 51. Each of the input terminals 31, 31 of the other DC / AC converters 30 other than the nearest DC / AC converter 30 is connected to each of the input terminals 31, 31 of the adjacent DC / AC converter 30 by each of the DC wirings 51, 51. As a result, DC power is supplied from the same DC power supply device 20 to the multiple DC / AC converters 30 connected to the DC wirings 51, 51.

[0014] The DC / AC conversion device 30 converts the DC power supplied from the DC power supply device 20 via DC wiring 51, 51 into AC power of an operating frequency, and outputs the converted AC power from output terminals 32, 32. The voltage value of the output power of the DC / AC conversion device 30 is, for example, 200 V, but is not limited to this.

[0015] Each of the power transmission devices 40 of the multiple power transmission devices 40 is connected in parallel to the DC / AC conversion device 30. Specifically, each of the output terminals 32, 32 of the DC / AC conversion device 30 is connected to each of the power transmission device terminals 41, 41 of the nearest power transmission device 40 among the multiple power transmission devices 40 that is closest to the DC / AC conversion device 30 by each of the AC wirings 52, 52. Each of the power transmission device terminals 41, 41 of the other power transmission devices 40 that are not the nearest power transmission device 40 is connected to each of the power transmission device terminals 41, 41 of the adjacent power transmission device 40 by each of the AC wirings 52, 52. As a result, AC power is supplied from the same DC / AC conversion device 30 to the multiple power transmission devices 40 connected to the AC wirings 52, 52.

[0016] The power transmitting device 40 applies AC power supplied from the DC / AC conversion device 30 via AC wiring 52, 52 to a built-in power transmitting coil L1 (FIG. 2), thereby performing contactless power supply to the power receiving device 80.

[0017] A2.Circuit configuration of the non-contact power supply system: As shown in FIG. 2, the DC power supply device 20 has a line filter 23 and a PFC circuit 24 in addition to the above configuration. The line filter 23 removes noise from the AC power supplied from the system power supply GPS. The PFC circuit 24 converts the AC power that has passed through the line filter 23 into DC power and outputs it. The PFC circuit 24 is a power factor correction circuit having a circuit configuration for making its own power factor closer to 1. Specifically, the PFC circuit 24 has a rectifier, a smoothing capacitor, and the like. The PFC circuit 24 outputs the generated DC power from the power supply output terminals 22, 22.

[0018] In addition to the above configuration, the DC / AC conversion device 30 has an inverter 33, a high-frequency filter 34, and an inverter control unit 35. The inverter 33 converts the DC power supplied from the DC power supply device 20 into AC power having a high-frequency operating frequency. In this embodiment, the operating frequency is 85 kHz. The inverter control unit 35 drives the inverter 33. The high-frequency filter 34 removes high-frequency noise from the AC power output from the inverter 33. The AC power that has passed through the high-frequency filter 34 is output from output terminals 32, 32.

[0019] In addition to the above configuration, the power transmitting device 40 has a power transmitting resonant circuit 44 and a switching circuit 46. The power transmitting resonant circuit 44 has a power transmitting coil L1, a power transmitting capacitor C1, and a first switch SW1. The power transmitting capacitor C1 has a function of putting the power transmitting resonant circuit 44 in a resonant state at the operating frequency and putting the power transmitting resonant circuit 44 in a non-resonant state at the operating frequency. The power transmitting capacitor C1 includes a first power transmitting capacitor C11 and a second power transmitting capacitor C12.

[0020] The first power transmitting capacitor C11 is connected in series with the power transmitting coil L1. The second power transmitting capacitor C12 is connected in series with the first switch SW1. The connection between the second power transmitting capacitor C12 and the first switch SW1 is connected in parallel with the first power transmitting capacitor C11. The first switch SW1 is a bidirectional switch to which the source terminals of two FETs (Field effect transistors) are connected. A switching signal Sig1 output from a switching circuit 46 is input to the gate terminals of the two FETs. This controls the on / off state of the first switch SW1.

[0021] When a high-level switching signal Sig1 is input to the first switch SW1, the first switch SW1 is turned on, i.e., conductive, and a current flows through the second power transmitting capacitor C12. When the first switch SW1 is turned on, the first power transmitting capacitor C11, the second power transmitting capacitor C12, and the power transmitting coil L1 make the power transmitting resonant circuit 44 resonate. On the other hand, when a low-level switching signal Sig1 is input to the first switch SW1, the first switch SW1 is turned off, i.e., non-conductive. Then, the resonant frequency of the resonant circuit formed by the first power transmitting capacitor C11 and the power transmitting coil L1 deviates from the operating frequency, and the power transmitting resonant circuit 44 is in a non-resonant state.

[0022] As shown in Fig. 9, the power receiving device 80 includes a power receiving resonant circuit 81 that includes at least a power receiving coil L2. Note that the power receiving device 80 is omitted in Fig. 2.

[0023] When the switching circuit 46 shown in FIG. 2 detects that the power receiving coil L2 (FIG. 9) is in the vicinity of the power transmitting coil L1, it switches the first switch SW1 from the off state to the on state using the switching signal Sig1. This sets the power transmitting resonant circuit 44 to a resonant state. When the power transmitting coil L1 and the power receiving coil L2 are magnetically coupled, the resonant frequency of the power transmitting resonant circuit 44 and the resonant frequency of the power receiving resonant circuit 81 are set to be substantially the same. This allows contactless power supply to the power receiving coil L2 by magnetic field coupling between the power transmitting coil L1 and the power receiving coil L2.

[0024] Here, the rated power of the DC power supply device 20 is greater than the rated power of the DC / AC conversion device 30. Therefore, as shown in Fig. 1, one DC power supply device 20 can supply DC power to a plurality of DC / AC conversion devices 30. In this embodiment, when an additional DC / AC conversion device 30 is installed, the input terminals 31, 31 of the nearest DC / AC conversion device 30 are connected to the input terminals 31, 31 of the newly installed DC / AC conversion device 30 by DC wiring 51, 51. Since the rated power of the DC power supply device 20 is greater than the rated power of the DC / AC conversion device 30, an additional DC / AC conversion device 30 can be connected to one DC power supply device 20 that has already been installed.

[0025] Similarly, for the power transmission device 40, the rated power of the DC / AC conversion device 30 is set to a value that allows power to be supplied to a plurality of power transmission devices 40. Therefore, it is possible to connect an additional power transmission device 40 to one DC / AC conversion device 30 that is already installed.

[0026] As described above, when a DC / AC conversion device 30 is added, the new DC / AC conversion device 30 and the already installed DC / AC conversion device 30 are connected with DC wirings 51, 51, so that the new DC / AC conversion device 30 can receive power supply from the DC power supply device 20. This makes it possible to reduce the number of steps required for installation compared to the case where the new DC / AC conversion device 30 and the DC power supply device 20 are connected with DC wirings 51, 51. Similarly, when a power transmission device 40 is added, the number of steps required for installation can be reduced by connecting the new power transmission device 40 and the already installed power transmission device 40 with AC wirings 52, 52.

[0027] In this embodiment, when the non-contact power supply device 10 has a plurality of power transmission devices 40, a difference in power supply efficiency between the plurality of power transmission devices 40 can be reduced by installing a plurality of DC / AC conversion devices 30 for one direct current power supply device 20. If AC power is supplied from one DC / AC conversion device 30 to all the power transmission devices 40 of the non-contact power supply device 10, the total length of the AC wiring 52 is likely to be long. The longer the AC wiring 52, the larger the parasitic components such as parasitic inductance and parasitic capacitance become. The lengths of the AC wirings 52, 52 are different between the power transmission device 40 close to the DC / AC conversion device 30 and the power transmission device 40 far from the DC / AC conversion device 30, and therefore the magnitudes of the parasitic components are different between the two. Therefore, the impedances of the current paths from the DC / AC conversion device 30 to the power transmission coil L1 are different between the two, and therefore the currents flowing through the power transmission coil L1 are different between the two for the AC power output from the DC / AC conversion device 30. Therefore, the longer the overall length of the AC wiring 52, the greater the difference in power supply efficiency between the two. In this regard, according to the present embodiment, when a plurality of power transmission devices 40 are installed, DC power is distributed to a plurality of DC / AC conversion devices 30, and AC power is supplied from each DC / AC conversion device 30 to the power transmission device 40. As a result, the range in which the power wiring from the DC power supply device 20 to the power transmission device 40 is laid is divided into a range in which the DC wiring 51, 51 is laid and a range in which the AC wiring 52, 52 is laid, thereby making it possible to shorten the overall length of the AC wiring 52, 52. Therefore, the difference in power supply characteristics between each of the power transmission devices 40 among the plurality of power transmission devices 40 can be reduced.

[0028] In addition, in order to compensate for the difference in impedance of the current path to the power transmission coil L1 caused by the increase in the overall length of the AC wiring 52, 52, a configuration in which a compensating capacitor unit is disposed between the DC / AC conversion device 30 and the power transmission device 40 is also considered. However, in this case, it is necessary to prepare a compensating capacitor unit in addition to the DC / AC conversion device 30. In this respect, according to the present embodiment, since a compensating capacitor unit is not used, it is possible to suppress an increase in the number of parts required for installation of the non-contact power supply device 10. In addition, AC loss occurs in the wiring through which AC power is transmitted. And, in order to reduce AC loss, the wire material used as the AC wiring 52, 52 tends to be more expensive than the wire material used for the DC wiring 51, 51. In this respect, in the present embodiment, the range in which the power wiring from the direct-current power supply device 20 to the power transmission device 40 is laid is divided into the range in which the DC wiring 51, 51 is laid and the range in which the AC wiring 52, 52 is laid, so that the length of the AC wiring 52, 52 used can be shortened, and the installation cost can be reduced. Furthermore, by shortening the length of the AC wiring 52, 52 used, AC loss can be reduced.

[0029] According to the first embodiment described above, the non-contact power supply device 10 includes the DC power supply device 20 and the DC / AC conversion device 30. The rated power of the DC power supply device 20 is greater than the rated power of the DC / AC conversion device 30. As a result, when the power transmission device 40 is to be added, a new DC / AC conversion device 30 can be added and the power transmission device 40 can be connected to the added DC / AC conversion device 30. When a plurality of power transmission devices 40 are connected to one DC power supply device 20, the range in which the power wiring from the DC power supply device 20 to the power transmission device 40 is laid is divided into a range in which the DC wirings 51, 51 are laid and a range in which the AC wirings 52, 52 are laid. This makes it possible to shorten the length of the AC wirings 52, 52 compared to the case in which the AC wirings 52, 52 are used to wire from one DC / AC conversion device 30 to all the power transmission devices 40. Therefore, even when multiple power transmission devices 40 are arranged, the difference in distance between the DC / AC conversion device 30 and each power transmission device 40 can be made small, making it possible to prevent differences in power supply efficiency caused by longer differences in the lengths of the AC wirings 52, 52.

[0030] B. Second embodiment: 3, the contactless power supply device 210 according to the second embodiment differs from the first embodiment in the method of connecting a plurality of DC / AC conversion devices 30 to the direct-current power supply device 20 and the method of connecting a plurality of power transmission devices 40 to the DC / AC conversion device 30. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

[0031] In this embodiment, among the multiple DC / AC converters 30, the farthest DC / AC converter 30E, which is the DC / AC converter 30 farthest from the DC power supply 20, is connected to the DC power supply 20 by DC wiring 51, 51. The other DC / AC converters 30 except for the farthest DC / AC converter 30E are connected using DC wiring 51, 51 branched from the DC wiring 51, 51 connecting the DC power supply 20 and the farthest DC / AC converter 30E. Specifically, a connector is attached to the branch point of the DC wiring 51, 51, and the branched DC wiring 51, 51 is connected to the connector. Note that "farthest from the DC power supply 20" means that the distance to the DC power supply 20 is the longest.

[0032] Similarly, among the multiple power transmission devices 40, the farthest power transmission device 40E, which is the power transmission device 40 farthest from the DC / AC conversion device 30, is connected to the DC / AC conversion device 30 by AC wiring 52, 52. The other power transmission devices 40 except for the farthest power transmission device 40E are connected using AC wiring 52, 52 branching off from the AC wiring 52, 52 connecting the DC / AC conversion device 30 and the farthest power transmission device 40E.

[0033] The length LE2 of the AC wiring 52, 52 connecting the power transmission device terminal 41, 41 of the power transmission device 40 that is closest to the DC / AC conversion device 30 and the output terminal 32, 32 of the DC / AC conversion device 30 is shorter than the length LE1 of the DC wiring 51, 51 connecting the input terminal 31, 31 of the farthest DC / AC conversion device 30E and the power output terminal 22 of the direct-current power supply device 20. The length LE1 of the DC wiring 51, 51 is the length of the longer DC wiring 51 of the two DC wirings 51. The length LE2 of the AC wiring 52, 52 is the length of the longer AC wiring 52 of the two AC wirings 52. In addition, "closest to the DC / AC conversion device 30" means that the distance to the DC / AC conversion device 30 is the shortest. By making the length LE2 shorter than the length LE1, the effect of reducing the difference in power supply efficiency can be further improved. Furthermore, when multiple power transmission devices 40 are connected, the difference in power supply efficiency for all of the power transmission devices 40 can be reduced, so it is preferable to set the length of the AC wiring 52, 52 connecting the power transmission device terminals 41, 41 of the farthest power transmission device 40E and the output terminals 32, 32 of the DC / AC conversion device 30 shorter than the length LE1.

[0034] In practice, when multiple power transmitting devices 40 are installed, the DC / AC conversion devices 30 are arranged so as to satisfy the above-mentioned magnitude relationship between the length LE2 and the length LE1, thereby realizing the above-mentioned magnitude relationship. In other words, when the installation range of the multiple power transmitting devices 40 to be arranged is wide, the installation range is divided, and the DC / AC conversion devices 30 are arranged in each divided installation range. In this way, the above-mentioned magnitude relationship between the length LE2 and the length LE1 can be satisfied.

[0035] According to the second embodiment described above, the same effect as the first embodiment can be obtained, and the effect of reducing the difference in power supply efficiency can be further improved by making the length LE2 shorter than the length LE1. In addition, the non-contact power supply device 210 has a plurality of DC / AC conversion devices 30 and a plurality of power transmission devices 40. The direct current power supply device 20 and the plurality of DC / AC conversion devices 30 are connected by DC wirings 51, 51. The DC / AC conversion device 30 and the plurality of power transmission devices 40 are connected by AC wirings 52, 52. In this way, by dividing the range in which the power wiring from the direct current power supply device 20 to the power transmission device 40 is laid into the range in which the DC wirings 51, 51 are laid and the range in which the AC wirings 52, 52 are laid, the length of the AC wirings 52, 52 can be shortened compared to the case in which the AC wirings 52, 52 are laid from one DC / AC conversion device 30 to all the power transmission devices 40. Therefore, it is possible to make it difficult for a difference in power supply efficiency to occur between the power transmission devices 40.

[0036] C. Third embodiment: As shown in Fig. 4, the contactless power supply device 310 according to the third embodiment differs from the above-described embodiments in that it includes a power transmission control device 60. The same components as those in the above-described embodiments are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate. In this embodiment, a form in which the contactless power supply device 310 includes four DC / AC conversion devices 30 will be described as an example.

[0037] The power transmission control device 60 controls the multiple DC / AC conversion devices 30. The power transmission control device 60 transmits a synchronization signal Sig2 to each of the multiple DC / AC conversion devices 30. Specifically, the power transmission control device 60 and each DC / AC conversion device 30 are connected by a signal line 53 that transmits the synchronization signal Sig2.

[0038] The inverter 33 has four switching elements Q1, Q2, Q3, and Q4 that form a bridge circuit. In this embodiment, the switching elements Q1 to Q4 are realized by MOSFETs (metal-oxide-semiconductor field-effect transistors).

[0039] As described above, the inverter control unit 35 drives the inverter 33. Specifically, the inverter control unit 35 inputs a PWM control signal for setting each of the switching elements Q1 to Q4 to an ON state or an OFF state to the gate terminal of each of the switching elements Q1 to Q4. The inverter control unit 35 sets the pair of the switching elements Q1 and Q4 and the pair of the switching elements Q2 and Q3 to an ON state or an OFF state in a mutually complementary manner. Specifically, during a period in which the PWM control signal input to the switching elements Q1 and Q4 is an ON voltage that sets the switching elements Q1 and Q4 to an ON state, the PWM control signal input to the switching elements Q2 and Q3 is set to an OFF voltage that sets the switching elements Q2 and Q3 to an OFF state. Similarly, during a period in which the PWM control signal input to the switching elements Q1 and Q4 is an OFF voltage, the PWM control signal input to the switching elements Q2 and Q3 is set to an ON voltage. The PWM control signal is periodically switched from either the ON voltage or the OFF voltage to the other. The inverter control unit 35 adjusts the duty ratio, which is the ratio of the period during which the ON voltage is output to one period, to adjust the output voltage of the DC / AC conversion device 30.

[0040] In this embodiment, the high frequency filter 34 is a fourth-order filter composed of an inductor and a capacitor. Note that the high frequency filter 34 is not limited to a fourth-order filter, and filters with other circuit configurations can be used.

[0041] The inverter control unit 35 uses the received synchronization signal Sig2 to control the phase of the output power of the DC / AC conversion device 30. In particular, the inverter control unit 35 controls the phase of the output voltage of the DC / AC conversion device 30. The power transmission control device 60 controls the multiple DC / AC conversion devices 30 so that the phases of the output power of at least two DC / AC conversion devices 30 are different from each other. This prevents currents of the same phase from flowing through the multiple DC / AC conversion devices 30, thereby reducing the ripple of the output voltage of the DC power supply device 20 in the previous stage of the DC / AC conversion device 30. This allows the smoothing capacitor of the PFC circuit 24 of the DC power supply device 20 to be miniaturized. In addition, the influence of EMC (Electromagnetic Compatibility) caused by the flow of ripple currents through the DC wirings 51 and 52 can be reduced.

[0042] In this embodiment, furthermore, all the DC / AC conversion devices 30 connected to the DC power supply device 20 are controlled so that the phases of the waveforms of the output voltages of the respective DC / AC conversion devices 30 are different from each other.

[0043] The DC / AC converters 30 are assigned device numbers in advance. In this embodiment, the device number of the DC / AC converter 30 that is the shortest distance from the DC power supply 20 is set to "1", and the device numbers are assigned to the DC / AC converters 30 in ascending order of integers so that the number increases as the distance from the DC power supply 20 increases. When the device number connected to the DC power supply 20 is "N (N is an integer of 1 or more)" and the total number of the DC / AC converters 30 is "X (X is an integer of 2 or more)", the power transmission control device 60 controls the DC / AC converters so that the waveform of the output power of the Nth DC / AC converter 30 becomes a waveform whose phase is shifted by (N-1)π / X [rad] from a predetermined reference waveform. (N-1)π / X is also called a phase correction value. In this embodiment, the waveform of the output voltage of the DC / AC converter 30 with the device number "1" is set to become a predetermined reference waveform.

[0044] As shown in FIG. 5, the output voltage of the inverter 33 built in the DC / AC converter 30 with the device number "1" is a square wave with a phase of 0 rad and a period of Ts [s] at time ts. The output voltage waveform of the inverter 33 built in the DC / AC converter 30 with the device number "2" is a waveform shifted by (1π / 4) [rad] from the reference waveform because N=2, X=4. In other words, it is a square wave with a phase of 0 rad at time (ts+Ts / 8). Similarly, the output voltage waveform of the inverter 33 built in the DC / AC converter 30 with the device number "3" is a waveform shifted by (1π / 2) [rad] from the reference waveform. The output voltage waveform of the inverter 33 built in the DC / AC converter 30 with the device number "4" is a waveform shifted by (3π / 4) [rad] from the reference waveform. In this way, the phases of the waveforms of the output voltages of all the DC / AC converters 30 connected to the DC power supply 20 are different from each other. Therefore, the phases of the output currents of the four DC / AC converters 30 are different from each other, so that the ripple of the output voltage of the DC power supply 20 at the front stage can be further reduced.

[0045] In this embodiment, the power transmission control device 60 transmits the device number and the phase correction value to each DC / AC conversion device 30. The DC / AC conversion device 30 stores the received device number and the phase correction value in a memory (not shown) built in the inverter control unit 35. The inverter control unit 35 drives the inverter 33 using the phase correction value and the synchronization signal Sig2. As another embodiment of the method for setting the device number and the phase correction value, the device number and the phase correction value may be set in the DC / AC conversion device 30 by an operator, instead of communication between the power transmission control device 60 and the DC / AC conversion device 30. Also, instead of the above phase correction value, "(N-1)Ts / (2X)" may be transmitted as a time correction value. The time correction value is the difference between the reference time when the phase of the reference waveform is 0 rad and the time when the phase of the output waveform of the device itself is 0 rad.

[0046] In the present embodiment, a case has been described in which the phases of the waveforms of the output voltages of all the DC / AC conversion devices 30 connected to the DC power supply device 20 are controlled to be different from each other. However, the present invention is not limited to this, and the phases of the waveforms of the output voltages of at least two of the multiple DC / AC conversion devices 30 connected to the DC power supply device 20 may be controlled to be different from each other. Even when there are multiple DC / AC conversion devices 30 that output output voltages of the same phase, the ripple of the output voltage of the DC power supply device 20 can be reduced more than when all the DC / AC conversion devices 30 output output voltages of the same waveform. As in the present embodiment, when the phases of the waveforms of the output voltages of all the DC / AC conversion devices 30 connected to the DC power supply device 20 are different from each other, the effect of reducing the ripple of the output voltage of the DC power supply device 20 can be improved, which is preferable.

[0047] According to the third embodiment described above, the same effects as those of the first embodiment are achieved. Moreover, the power transmission control device 60 controls the multiple DC / AC conversion devices 30 so that the phases of the output power of at least two of the multiple DC / AC conversion devices 30 are different from each other. Thus, the ripple of the output voltage of the direct-current power supply device 20 can be reduced. Moreover, the power transmission control device controls the multiple DC / AC conversion devices 30 so that the waveform of the output power of the Nth DC / AC conversion device 30 becomes a waveform whose phase is shifted by the phase correction value from the reference waveform. Thus, the effect of reducing the ripple of the output voltage of the direct-current power supply device 20 can be improved.

[0048] D. Fourth embodiment: In the third embodiment, communication is performed between the power transmission control device 60 and the DC / AC conversion device 30 using signal lines 53, 53. The present embodiment shown in Fig. 6 differs from the third embodiment in that wireless communication is performed between the power transmission control device 60 and the DC / AC conversion device 30. The same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

[0049] The inverter control unit 35 included in the non-contact power supply device 410 according to this embodiment shown in Fig. 6 has a communication unit (not shown). The inverter control unit 35 transmits a synchronization signal Sig2 by wireless communication with the power transmission control device 60. According to this embodiment, the same effects as those of the above-mentioned embodiment can be obtained, and the effort required for laying the signal lines 53, 53 can be eliminated, making it easier to lay the non-contact power supply device 310.

[0050] E. Fifth embodiment: The non-contact power supply device 510 according to the present embodiment shown in Fig. 7 includes two DC / AC conversion devices 30. The output voltages of the two DC / AC conversion devices 30 are different from each other, which is different from each other. The same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

[0051] One of the two DC / AC conversion devices 30 is called the first DC / AC conversion device 30A as the first DC / AC conversion device, and the other is called the second DC / AC conversion device 30B as the second DC / AC conversion device. The first DC / AC conversion device 30A and the second DC / AC conversion device 30B are installed in different sections. Each of the two DC / AC conversion devices 30 corresponds to each of two types of power receiving devices 80 having different required power. One of the two types of power receiving devices 80 is called the first power receiving device 80A as the first power receiving device, and the other is called the second power receiving device 80B as the second power receiving device. The power transmitting device 40 that wirelessly feeds power to the first power receiving device 80A is also called the first power transmitting device 40. The power transmitting device 40 that wirelessly feeds power to the second power receiving device 80B is also called the second power transmitting device 40. The first power receiving device 80A and the second power receiving device 80B have different required power. In particular, the required maximum power of the first power receiving device 80A is greater than the required maximum power of the second power receiving device 80B. The first DC / AC conversion device 30A supplies AC power to the first power transmission device 40 that wirelessly feeds power to the first power receiving device 80A. The second DC / AC conversion device 30B supplies AC power to the second power transmission device 40 that wirelessly feeds power to the second power receiving device 80B.

[0052] The first power receiving device 80A is mounted on an industrial robot that is fixed at a fixed installation location. The first power receiving device 80A can always receive contactless power supply because the relative position of the first power receiving device 80A to the first power transmitting device 40 does not change. In contrast, the second power receiving device 80B is mounted on a movable AGV. The relative position of the second power receiving device 80B to the second power transmitting device 40 changes. Therefore, the second power receiving device 80B can receive contactless power supply when it is located in a position range where power can be supplied from the second power transmitting device 40. Therefore, the first power receiving device 80A can receive power on average, so the instantaneous power of the requested power is small. In contrast, the second power receiving device 80B cannot receive power on average, so the instantaneous power of the requested power is large. The voltage value of the requested maximum power of the second power receiving device 80B is larger than the voltage value of the requested maximum power of the first power receiving device 80A.

[0053] The output voltage of the second DC / AC conversion device 30B is larger than the output voltage of the first DC / AC conversion device 30A. As a result, each of the first DC / AC conversion device 30A and the second DC / AC conversion device 30B can adequately supply the required power of the power receiving device 80 to which each power transmitting device 40 connected thereto wirelessly supplies power.

[0054] Specifically, the first DC / AC conversion device 30A and the second DC / AC conversion device 30B adjust their own output voltages by adjusting the duty ratio of the PWM control signal. That is, the maximum duty ratio of the PWM control signal of the first DC / AC conversion device 30A is set to be smaller than the maximum duty ratio of the PWM control signal of the second DC / AC conversion device 30B.

[0055] According to the fifth embodiment described above, the same effects as those of the above embodiments are achieved, and the non-contact power supply device 510 includes a first DC / AC conversion device 30A and a second DC / AC conversion device 30B. The maximum duty ratio of the PWM control signal of the first DC / AC conversion device 30A is set to be smaller than the maximum duty ratio of the PWM control signal of the second DC / AC conversion device 30B. This makes it possible to supply power that satisfies the required power of each of the power receiving devices 80 to a plurality of power receiving devices 80 having different required powers.

[0056] F. Sixth embodiment: In the fifth embodiment, the output voltage is adjusted by adjusting the duty ratio of the PWM control signal output by the inverter control unit 35. This embodiment differs from the fifth embodiment in that the output voltage of the DC / AC conversion device 30 is adjusted by adjusting the impedance of the high frequency filter 34 of the DC / AC conversion device 30. The same components as those in the above embodiments are denoted by the same reference numerals, and detailed explanations are omitted as appropriate. Specifically, the circuit configuration of the DC / AC conversion device 30 is the same as that of the third embodiment shown in FIG. 4, and therefore will be described using the reference numerals in FIG. 4. The configuration of the non-contact power supply device 510 is the same as that of the fifth embodiment shown in FIG. 7, and therefore will be described using the reference numerals in FIG. 7.

[0057] In the present embodiment, similarly to the fifth embodiment, the contactless power supply device 510 includes a first DC / AC conversion device 30A connected to a first power transmission device 40 that contactlessly supplies power to a first power reception device 80A, and a second DC / AC conversion device 30B connected to a second power transmission device 40 that contactlessly supplies power to a second power reception device 80B. The voltage value of the maximum power required by the second power reception device 80B is greater than the voltage value of the maximum power required by the first power reception device 80A.

[0058] In this embodiment, the high frequency filter 34 of the first DC / AC conversion device 30A and the high frequency filter 34 of the second DC / AC conversion device 30B have different impedances. In detail, the impedance of the high frequency filter 34 of the first DC / AC conversion device 30A is set so that the fundamental wave component of the output voltage of the first DC / AC conversion device 30A is smaller than the fundamental wave component of the output voltage of the second DC / AC conversion device 30B. This makes it possible to make the output voltage of the second DC / AC conversion device 30B larger than the output voltage of the first DC / AC conversion device 30A.

[0059] According to the sixth embodiment described above, it is possible to achieve the same effects as the above embodiments.

[0060] G. Seventh embodiment: In the fifth embodiment, the output voltage is adjusted by adjusting the duty ratio of the PWM control signal output by the inverter control unit 35. A non-contact power supply device 710 according to this embodiment shown in Fig. 8 differs from the fifth embodiment in that the output voltage of the DC / AC conversion device 30 is adjusted by adjusting the turns ratio of the transformer 36 included in the DC / AC conversion device 730. The same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

[0061] 8, the DC / AC conversion device 730 has a transformer 36 in addition to the above configuration. The transformer 36 is disposed between the inverter 33 and the high-frequency filter 34. The transformer 36 steps up or down the output voltage of the inverter 33. The output power of the transformer 36 is input to the high-frequency filter 34. In this embodiment, the high-frequency filter 34 is composed of a coil and a capacitor connected in series to each of the two power wirings, and a coil and a capacitor connected between the two power wirings.

[0062] In the present embodiment, similarly to the fifth embodiment, the contactless power supply device 510 includes a first DC / AC conversion device 30A connected to a first power transmission device 40 that contactlessly supplies power to a first power reception device 80A, and a second DC / AC conversion device 30B connected to a second power transmission device 40 that contactlessly supplies power to a second power reception device 80B. The voltage value of the maximum power required by the second power reception device 80B is greater than the voltage value of the maximum power required by the first power reception device 80A.

[0063] In this embodiment, the turns ratio of the transformer 36 of the first DC / AC conversion device 30A and the turns ratio of the transformer of the second DC / AC conversion device 30B are different from each other. In detail, the turns ratio of the transformer 36 of the first DC / AC conversion device 30A is larger than the turns ratio of the transformer of the second DC / AC conversion device 30B. This makes it possible to make the output voltage of the second DC / AC conversion device 30B larger than the output voltage of the first DC / AC conversion device 30A.

[0064] According to the seventh embodiment described above, it is possible to achieve the same effects as the above embodiments.

[0065] H. Eighth embodiment: In the first embodiment, the power transmitting device 40 includes a power transmitting resonant circuit 44, and wireless power feeding is performed using a power transmitting coil L1 included in the power transmitting resonant circuit 44. A power transmitting device 840 according to this embodiment shown in Fig. 9 has a circuit configuration different from that of the power transmitting device 40. The same reference numerals are used to designate the same configurations as those in the above embodiments, and detailed descriptions thereof will be omitted as appropriate.

[0066] In addition to the above configuration, the power transmitting device 840 has a tertiary resonant circuit 48. The tertiary resonant circuit 48 is used to form or cut off a power transmission path between the power transmitting device 40 and the power receiving device 80. The tertiary resonant circuit 48 has a tertiary coil L3, a tertiary capacitor C3, and a second switch SW2. The tertiary capacitor C3 and the second switch SW2 are connected in parallel to the tertiary coil L3. The second switch SW2 is a bidirectional switch similar to the first switch SW1. The tertiary coil L3 is disposed at a position where it can be magnetically coupled to the power transmitting coil L1. As a result, when the power transmitting coil L1 and the power receiving coil L2 are magnetically coupled to each other, the power transmitting coil L1, the power receiving coil L2, and the tertiary coil L3 are magnetically coupled to each other.

[0067] The capacitance value of the tertiary capacitor C3 is set to a value that causes the parallel resonant circuit formed by the tertiary coil L3 and the tertiary capacitor C3 to enter a resonant state when the transmitting coil L1, the receiving coil L2, and the tertiary coil L3 are magnetically coupled to each other.

[0068] The power receiving device 80 is mounted on a moving body as in the first embodiment, and when the power receiving coil L2 approaches the power transmitting coil L1, the switching circuit 46 switches the power transmitting resonant circuit 44 and the tertiary resonant circuit 48 from a non-resonant state to a resonant state, and switches the power transmitting device 40 from a standby state to a power supplying state. Specifically, as described above, the switching circuit 46 switches the first switch SW1 from an off state to an on state, and switches the second switch SW2 from an on state to an off state. When the second switch SW2 is switched to the off state, the parallel resonant circuit formed by the tertiary coil L3 and the tertiary capacitor C3 enters a resonant state. As a result, a power supply current flows through the power transmitting coil L1, and power is supplied contactlessly to the power receiving coil L2.

[0069] On the other hand, when the power receiving coil L2 is separated from the power transmitting coil L1, the switching circuit 46 switches the power transmitting resonant circuit 44 and the tertiary resonant circuit 48 from a resonant state to a non-resonant state, and switches the power transmitting device 40 from a power supply state to a standby state. Specifically, as described above, the switching circuit 46 switches the first switch SW1 from an on state to an off state, and switches the second switch SW2 from an off state to an on state. When the second switch SW2 is switched to the on state, both terminals of the tertiary coil L3 are short-circuited, and the tertiary resonant circuit 48 is in a non-resonant state. As a result, the power transmitting device 40 is switched to a standby state in which a standby current smaller than the power supply current flows through the power transmitting coil L1.

[0070] The power transmitting coils L1 are arranged in an array, and the power receiving coil L2 is supplied with power from the nearest power transmitting coil L1 among the arranged power transmitting coils L1. That is, the arranged power transmitting coils L1 are switched from the standby state to the power supplying state in order of arrangement. For this reason, a magnetic flux generated by the power transmitting coil L1 of the power transmitting device 40 set to the power supplying state may penetrate the power transmitting coil L1 of the adjacent power transmitting device 40 set to the standby state. Here, the tertiary resonant circuit 48 is set to the non-resonant state, so that the magnetic flux generated in the power transmitting coil L1 can be reduced.

[0071] According to the eighth embodiment described above, it is possible to achieve the same effects as the above embodiments.

[0072] I. Ninth embodiment: A power transmitting device 940 according to this embodiment has a different circuit configuration from the power transmitting device 840 according to the eighth embodiment. The same components as those in the above embodiments are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0073] As shown in Fig. 10, the power transmitting device 940 has a tertiary resonant circuit 948. The tertiary resonant circuit 948 has a fourth capacitor C4 and a third switch SW3 in addition to a tertiary coil L3, a tertiary capacitor C3, and a second switch SW2. The fourth capacitor C4 is connected in series with the third switch SW3. The connection between the fourth capacitor C4 and the third switch SW3 is connected in parallel with the tertiary coil L3. The third switch SW3 is realized by one FET.

[0074] The third switch SW3 is set to an on state when the tertiary resonant circuit 848 is set to a resonant state, and is set to an off state when the tertiary resonant circuit 848 is set to a non-resonant state. The combined capacitance of the tertiary capacitor C3 and the fourth capacitor C4 is set to a value that causes a parallel resonant circuit formed by the tertiary coil L3, the tertiary capacitor C3, and the fourth capacitor C4 to be in a resonant state when the power transmitting coil L1, the power receiving coil L2, and the tertiary coil L3 are magnetically coupled to each other.

[0075] When the power transmitting device 840 is set to a standby state, the switching circuit 46 sets the first switch SW1 to an off state, sets the second switch SW2 to an on state, and sets the third switch SW3 to an off state. On the other hand, when the power transmitting device 840 is set to a power supplying state, the switching circuit 46 sets the first switch SW1 to an on state, sets the second switch SW2 to an off state, and sets the third switch SW3 to an on state. The tertiary resonant circuit 848 is obtained by adding a third switch SW3 and a fourth capacitor C4 to the tertiary resonant circuit 48 of the eighth embodiment. This allows the resonant / non-resonant state of the tertiary resonant circuit 948 to be set not only by setting the on / off state of the second switch SW2 but also by setting the on / off state of the third switch SW3. Therefore, for example, even when a failure occurs that keeps the second switch SW2 in a constantly off state, the tertiary resonant circuit 948 can be set to a non-resonant state using the third switch SW3.

[0076] According to the ninth embodiment described above, it is possible to achieve the same effects as the above embodiments.

[0077] J. Other Embodiments: (J1) In the first embodiment, in the power transmitting resonant circuit 44, the power transmitting capacitor C1 is connected in series to the power transmitting coil L1. The circuit configuration of the power transmitting resonant circuit 44 and the circuit configuration of the power receiving resonant circuit 81 are not particularly limited. For example, in the power transmitting resonant circuit 44, the power transmitting capacitor C1 is connected in series to the power transmitting coil L1, and in the power receiving resonant circuit 81, the power receiving capacitor is connected in series to the power receiving coil L2, so-called SS type circuit configuration may be used. (a) Also, in the power transmitting resonant circuit 44, the power transmitting capacitor C1 is connected in parallel to the power transmitting coil L1, and in the power receiving resonant circuit 81, the power receiving capacitor is connected in series to the power receiving coil L2, so-called PS type circuit configuration may be used. (b) Also, in addition to the power transmitting capacitor C1 connected in series to the power transmitting coil L1, a capacitor connected in parallel to the power transmitting coil L1 is provided, and in the power receiving resonant circuit 81, two power receiving capacitors are connected in series to each of both terminals of the power receiving coil L2, so-called P-SS type circuit configuration may be used. (c) In addition to the power transmitting capacitor C1 connected in series to the power transmitting coil L1, a capacitor connected in parallel to the power transmitting coil L1 may be provided, and the power receiving resonant circuit 81 may have a so-called SP-PS type circuit configuration, which includes a first power receiving capacitor connected in series to the power receiving coil L2 and a second power receiving capacitor connected in parallel to the power receiving coil L2. (d) The power transmitting resonant circuit 44 may also have a closed circuit in which a coil and a capacitor are connected in series. The coil of this closed circuit is arranged at a position where it can be magnetically coupled to the power receiving coil L2 when the power transmitting coil L1 and the power receiving coil L2 are magnetically coupled. (e) Furthermore, the capacitor of the closed circuit may be connected in parallel to the coil, not in series. (f) The power transmitting resonant circuit 44 may also have a coil connected in series to the power transmitting coil L1 and a capacitor connected in parallel to the coil. This coil is arranged at a position where it can be magnetically coupled to the power receiving coil L2 when the power transmitting coil L1 and the power receiving coil L2 are magnetically coupled.

[0078] (J2) In the above third embodiment, the power transmission control device 60 controls the multiple DC / AC conversion devices 30 such that the phases of the output power of at least two of the multiple DC / AC conversion devices 30 are different from each other. As another embodiment, the power transmission control device 60 may control the multiple DC / AC conversion devices 30 such that the phases of the output power of each of the multiple DC / AC conversion devices 30 are the same as each other.

[0079] (J3) In the first embodiment, the switching elements Q1 to Q4 constituting the pulse generating circuit 82 are realized by MOSFETs. In another embodiment, the switching elements Q1 to Q4 may be realized by other semiconductor elements, for example, IGBTs (Insulated Gate Bipolar Transistors) connected to freewheeling diodes. The same applies to the first switch SW1, the second switch SW2, and the third switch SW3. In addition, the first switch SW1 and the second switch SW2 are not limited to bidirectional switches, and may be unidirectional switches composed of one switching element. The third switch SW3 may be a bidirectional switch.

[0080] (J4) In the first embodiment, adjacent DC / AC converters 30 are connected to each other by DC wiring 51, 51. In the second embodiment, the other DC / AC converters 30 except the farthest DC / AC converter 30E are connected to each other by DC wiring 51, 51 branched from the DC wiring 51, 51 connecting the DC power supply 20 and the farthest DC / AC converter 30E. As another form of connecting the DC power supply 20 and each DC / AC converter 30, the DC power supply 20 and each DC / AC converter 30 may be connected via a distributor such as a terminal block. Also, a plurality of DC / AC converters 30 may be connected to the power output terminals 22, 22 of the DC power supply 20. Similarly, as another form of connecting the DC / AC converter 30 and each power transmission device 40, the DC / AC converter 30 and each power transmission device 40 may be connected via a distributor such as a terminal block. Furthermore, a plurality of power transmitting devices 40 may be connected to the output terminals 32, 32 of the DC / AC conversion device 30.

[0081] The present disclosure is not limited to the above-mentioned embodiments and modifications, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in the embodiments and modifications corresponding to the technical features in each aspect described in the Summary of the Invention column can be appropriately replaced or combined in order to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0082] K: Other forms: The features of the present disclosure are as follows: (Form 1) A non-contact power supply device (10, 210 to 710) that supplies power to a power receiving device (80) in a non-contact manner, A DC power supply (20); A DC wiring (51) for transmitting the output power of the DC power supply device; At least one DC / AC converter (30, 730) connected to the DC wiring; an AC wiring (52) for transmitting output power of the DC / AC conversion device; At least one power transmission device (40, 840, 940) connected to the AC wiring; A contactless power supply device, wherein the rated power of the DC power supply device is greater than the rated power of the DC / AC conversion device. (Form 2) The non-contact power supply device according to aspect 1, A plurality of the DC / AC conversion devices are provided, A plurality of the power transmitting devices are provided, The DC power supply device has a power output terminal (22) that is connected to the DC wiring, Each of the plurality of DC / AC conversion devices has an input terminal (31) connected to the DC wiring and an output terminal (32) connected to the AC wiring, Each of the plurality of power transmission devices has a power transmission device terminal (41) that is connected to the AC wiring, a non-contact power supply device, wherein the length of the AC wiring connecting the power transmission device terminal of the power transmission device that is closest to the DC / AC conversion device among the plurality of power transmission devices and the output terminal of the DC / AC conversion device is shorter than the length of the DC wiring connecting the input terminal of the DC / AC conversion device that is farthest from the DC power supply device among the plurality of DC / AC conversion devices and the power output terminal of the DC power supply device. (Form 3) The non-contact power supply device according to aspect 1 or 2, A plurality of the DC / AC conversion devices are provided, Further, a power transmission control device that controls the plurality of DC / AC conversion devices is provided, The power transmission control device transmits a synchronization signal to each of the plurality of DC / AC conversion devices; Each of the plurality of DC / AC conversion devices includes an inverter (33) that outputs the output power, and an inverter control unit (35) that controls the inverter, The inverter control unit controls a phase of the output power by using the received synchronization signal, The power transmission control device is a non-contact power supply device that controls the multiple DC / AC conversion devices so that the phases of the output power of at least two DC / AC conversion devices among the multiple DC / AC conversion devices are different from each other. (Form 4) The non-contact power supply device according to aspect 3, The power transmission control device includes: a contactless power supply device which controls the plurality of DC / AC conversion devices so that a waveform of the output power of the Nth DC / AC conversion device becomes a waveform that is shifted in phase by (N-1)π / X [rad] with respect to a predetermined reference waveform, where the plurality of DC / AC conversion devices are assigned device numbers in order of proximity to the direct-current power supply device, the device numbers are N (N is an integer equal to or greater than 1) and the total number of the plurality of DC / AC conversion devices is X (X is an integer equal to or greater than 2). (Form 5) A non-contact power supply device according to any one of aspects 1 to 4, A plurality of the DC / AC conversion devices are provided, the plurality of DC / AC conversion devices include a first DC / AC conversion device to which a first power transmission device that performs contactless power supply to a first power receiving device is connected, and a second DC / AC conversion device to which a second power transmission device that performs contactless power supply to a second power receiving device whose required maximum power is greater than the required maximum power of the first power receiving device is connected, Each of the plurality of DC / AC conversion devices includes an inverter (33) that outputs the output power, and an inverter control unit (35) that controls the inverter by inputting a PWM control signal to the inverter, A contactless power supply device, wherein a maximum duty ratio of the PWM control signal of the first DC / AC conversion device is smaller than a maximum duty ratio of the PWM control signal of the second DC / AC conversion device. (Form 6) A non-contact power supply device according to any one of aspects 1 to 5, A plurality of the DC / AC conversion devices are provided, the plurality of DC / AC conversion devices include a first DC / AC conversion device connected to a first power transmission device that performs contactless power supply to the first power reception device, and a second DC / AC conversion device connected to a second power transmission device that performs contactless power supply to a second power reception device whose required maximum power is greater than the required maximum power of the first power reception device, Each of the plurality of DC / AC conversion devices includes an inverter (33) that outputs the output power, and a filter (34) connected to a downstream stage of the inverter, a contactless power supply device, wherein the impedance of the filter of the first DC / AC conversion device is set so that a fundamental wave component of an output voltage of the first DC / AC conversion device is smaller than a fundamental wave component of an output voltage of the second DC / AC conversion device. (Form 7) A contactless power supply device according to any one of aspects 1 to 6, A plurality of the DC / AC conversion devices are provided, the plurality of DC / AC conversion devices include a first DC / AC conversion device connected to a first power transmission device that performs contactless power supply to the first power reception device, and a second DC / AC conversion device connected to a second power transmission device that performs contactless power supply to a second power reception device whose required maximum power is greater than the required maximum power of the first power reception device, Each of the plurality of DC / AC conversion devices includes an inverter (33) that outputs the output power, and a transformer (36) connected to a downstream stage of the inverter, a turn ratio of the transformer included in the first DC / AC conversion device is greater than a turn ratio of the transformer included in the second DC / AC conversion device; (Form 8) A non-contact power supply device according to any one of aspects 1 to 7, the DC power supply device includes a PFC circuit (24) that is connected to a system power supply (GPS) and converts AC power supplied from the system power supply into DC power and outputs the DC power; The DC / AC conversion device includes an inverter (33) that converts the DC power output by the PFC circuit into AC power, The power transmitting device includes a power transmitting resonant circuit (44) having a power transmitting coil (L1) and a power transmitting capacitor (C1), and a switching circuit (46) that switches a state of the power transmitting resonant circuit between a resonant state and a non-resonant state, A plurality of the DC / AC conversion devices are provided, A non-contact power supply device including a plurality of the power transmission devices. [Explanation of symbols]

[0083] 10,210,310,410,510,710...Non-contact power supply device, 20...DC power supply device, 30,730...DC / AC conversion device, 40,840,940...Power transmission device, 51...DC wiring, 52...AC wiring, 80...Power receiving device

Claims

1. A non-contact power supply device (10, 210, 310, 410, 510, 710) that performs non-contact power supply to a power receiving device (80), a DC power supply device (20), a DC wiring (51) that transmits the output power of the DC power supply device, a plurality of DC / AC conversion devices (30, 730) connected to the DC wiring, a plurality of AC wirings (52) that transmit the output power of each of the plurality of DC / AC conversion devices, and a plurality of power transmission devices (40, 840, 940) respectively connected to the plurality of AC wirings, the DC power supply device has a power output terminal (22) connected to the DC wiring, each of the plurality of DC / AC conversion devices has an input terminal (31) connected to the DC wiring and an output terminal (32) connected to the AC wiring, each of the plurality of power transmission devices has a power transmission device terminal (41) connected to the AC wiring, the rated power of the DC power supply device is greater than the rated power of each of the plurality of DC / AC conversion devices, among the plurality of power transmission devices, the length of the AC wiring that connects the power transmission device terminal of the power transmission device closest to the connected DC / AC conversion device among the plurality of DC / AC conversion devices and the output terminal of the connected DC / AC conversion device is shorter than the length of the DC wiring that connects the input terminal of the DC / AC conversion device farthest from the DC power supply device among the plurality of DC / AC conversion devices and the power output terminal of the DC power supply device. The non-contact power supply device.

2. The non-contact power supply device according to claim 1, further comprising a power transmission control device that controls the plurality of DC / AC conversion devices, the power transmission control device transmits a synchronization signal to each of the plurality of DC / AC conversion devices, each of the plurality of DC / AC conversion devices has an inverter (33) that outputs the output power and an inverter control unit (35) that controls the inverter, the inverter control unit controls the phase of the output power using the received synchronization signal, the power transmission control device controls the plurality of DC / AC conversion devices such that the phases of the output powers of at least two of the plurality of DC / AC conversion devices are different from each other. The non-contact power supply device.

3. The non-contact power supply device according to claim 2, the power transmission control device is, Device numbers are assigned to each of the plurality of DC / AC converters in the order from the closest to the DC power supply device. When the device number is N (N is an integer of 1 or more) and the total number of the plurality of DC / AC converters is X (X is an integer of 2 or more), the phase of the waveform of the output power of the Nth DC / AC converter is shifted by (N - 1)π / X [rad] with respect to a predetermined reference waveform, and the plurality of DC / AC converters are controlled. A contactless power supply device.

4. The contactless power supply device according to claim 1, wherein the plurality of power transmission devices include a first power transmission device that performs contactless power supply to the first power reception device, and a second power transmission device that performs contactless power supply to a second power reception device having a required maximum power greater than the required maximum power of the first power reception device. The plurality of DC / AC converters include a first DC / AC converter to which the first power transmission device is connected, and a second DC / AC converter to which the second power transmission device is connected. Each of the plurality of DC / AC converters has an inverter (33) that outputs the output power, and an inverter control unit (35) that controls by inputting a PWM control signal to the inverter. A contactless power supply device, wherein the maximum duty ratio of the PWM control signal of the first DC / AC converter is smaller than the maximum duty ratio of the PWM control signal of the second DC / AC converter.

5. The contactless power supply device according to claim 1, wherein the plurality of power transmission devices include a first power transmission device that performs contactless power supply to the first power reception device, and a second power transmission device that performs contactless power supply to a second power reception device having a required maximum power greater than the required maximum power of the first power reception device. The plurality of DC / AC converters include a first DC / AC converter connected to the first power transmission device, and a second DC / AC converter connected to the second power transmission device. Each of the plurality of DC / AC converters has an inverter (33) that outputs the output power, and a filter (34) connected to the subsequent stage of the inverter. A contactless power supply device, wherein the impedance of the filter of the first DC / AC converter is set such that the fundamental wave component of the output voltage of the first DC / AC converter is smaller than the fundamental wave component of the output voltage of the second DC / AC converter.

6. The contactless power supply device according to claim 1, The plurality of power transmission devices include a first power transmission device that performs non-contact power supply to the first power reception device, and a second power transmission device that performs non-contact power supply to a second power reception device having a required maximum power greater than the required maximum power of the first power reception device. The plurality of DC / AC conversion devices include a first DC / AC conversion device connected to the first power transmission device and a second DC / AC conversion device connected to the second power transmission device. Each of the plurality of DC / AC conversion devices has an inverter (33) that outputs the output power and a transformer (36) connected to a subsequent stage of the inverter. A non-contact power supply device, wherein a turns ratio of the transformer included in the first DC / AC conversion device is larger than a turns ratio of the transformer included in the second DC / AC conversion device.

7. The non-contact power supply device according to claim 1, wherein the DC power supply device is connected to a utility power supply (GPS) and has a PFC circuit (24) that converts AC power supplied from the utility power supply into DC power and outputs the DC power. The DC / AC conversion device has an inverter (33) that converts the DC power output by the PFC circuit into AC power. Each of the plurality of power transmission devices has a power transmission resonance circuit (44) having a power transmission coil (L1) and a power transmission capacitor (C1), and a switching circuit (46) that switches a state of the power transmission resonance circuit between a resonance state and a non-resonance state.

Images