Non-contact power supply device

Abstract

A non-contact power supply device (10) for supplying power to a power receiving device (80) in a non-contact manner, the non-contact power supply device (10) comprising: a DC power supply device (20); a DC wiring (51) for transmitting the output power of the DC power supply device; at least one DC / AC conversion device (30) connected to the DC wiring; an AC wiring (52) for transmitting the output power of the DC / AC conversion device; and at least one power transmission device (40) connected to the AC wiring. The rated power of the DC power supply device is greater than the rated power of the DC / AC conversion device.

Description

[0001] Citation of relevant applications This application is based on Japanese Patent Application No. 2023-72897, filed on April 27, 2023, the contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to a contactless power supply device. Background Technology

[0003] Patent Document 1 discloses a contactless power supply system, which includes a high-frequency power supply device and a plurality of power transmission units connected to the high-frequency power supply device via a switch. Each of the plurality of power transmission units is connected in parallel with the high-frequency power supply device.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2017-51074 Summary of the Invention

[0005] In the aforementioned contactless power supply device, as the number of power supply units increases, the difference in the length of the wiring connecting the high-frequency power supply unit to the power supply unit between units close to and far from the high-frequency power supply unit becomes larger. The greater the difference in wiring length, the greater the difference in parasitic components such as parasitic inductance of the wiring. Therefore, differences in power supply efficiency may occur between power supply units close to and far from the high-frequency power supply unit.

[0006] This disclosure can be implemented in the following ways.

[0007] In one aspect of this disclosure, a contactless power supply device is provided to provide contactless power to a receiving device. The contactless power supply device includes: a DC power supply device; a DC wiring harness that supplies power to the output of the DC power supply device; at least one DC / AC converter connected to the DC wiring harness; an AC wiring harness that supplies power to the output of the DC / AC converter; and at least one power supply device connected to the AC wiring harness, wherein the rated power of the DC power supply device is greater than the rated power of the DC / AC converter.

[0008] According to this method, since the rated power of the DC power supply device is greater than that of the DC / AC conversion device, when adding power transmission devices, 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. Furthermore, when multiple power transmission devices are connected to the DC power supply device, the range of power wiring from the DC power supply device to the power transmission devices is distributed by the range of DC wiring and the range of AC wiring, which shortens the length of the AC wiring compared to laying AC wiring from one DC / AC conversion device to all power transmission devices. Therefore, even when multiple power transmission devices are configured, the difference in distance between the DC / AC conversion device and each power transmission device can be reduced, thus minimizing the possibility of differences in power supply efficiency caused by increased differences in AC wiring length. Attached Figure Description

[0009] The above-mentioned objects, other objects, features, and advantages of this disclosure will become clearer with reference to the accompanying drawings and the following detailed description. The accompanying drawings are described below.

[0010] Figure 1 This is a schematic structural diagram of the contactless power supply device according to the first embodiment.

[0011] Figure 2 This is a circuit diagram of the contactless power supply device according to the first embodiment.

[0012] Figure 3 This is a schematic structural diagram of the contactless power supply device according to the second embodiment.

[0013] Figure 4 This is a circuit diagram of the contactless power supply device according to the third embodiment.

[0014] Figure 5 This is a diagram showing the output waveform of the inverter according to the third embodiment.

[0015] Figure 6 This is a schematic structural diagram of the contactless power supply device according to the fourth embodiment.

[0016] Figure 7 This is a schematic structural diagram of the contactless power supply device according to the fifth embodiment.

[0017] Figure 8 This is a circuit diagram of the contactless power supply device according to the seventh embodiment.

[0018] Figure 9 This is a circuit diagram of the contactless power supply device according to the eighth embodiment.

[0019] Figure 10 This is a circuit diagram of the contactless power supply device according to the ninth embodiment. Detailed Implementation

[0020] A. First implementation method: A1. Structure of a contactless power supply system: like Figure 1 As shown, the contactless power supply device 10 includes a DC power supply device 20, multiple DC / AC conversion devices 30, multiple power transmission devices 40, DC wiring 51, 51, and AC wiring 52, 52. In this embodiment, the multiple power transmission devices 40 are buried beneath the road. The power transmission devices 40 supply power to the receiving device 80 installed on the vehicle, which is a moving body traveling on the road, during vehicle operation. Figure 9 Non-contact power supply is provided. Here, "driving" includes both situations where the vehicle is moving and situations where the vehicle stops due to waiting for a signal, etc. The vehicle may be, for example, an electric vehicle or a hybrid vehicle.

[0021] Furthermore, the mobile body equipped with the power receiving device 80 is not limited to vehicles traveling on roads; it can also be an AGV (Automated Guided Vehicle), a traveling robot, etc. Additionally, the power supply device 40 can be installed on a sidewalk or parking lot adjacent to the road, or in the path traveled by the AGV, rather than being installed beneath the road. Furthermore, the power supply device 40 can be installed not only in a road or path roughly parallel to the ground, but also on a side roughly perpendicular to the ground. Moreover, the device equipped with the power receiving device 80 may not be a mobile body, but a fixed device.

[0022] The DC power supply unit 20 has power input terminals 21, 21 and power output terminals 22, 22. The DC / AC converter 30 has input terminals 31, 31 and output terminals 32, 32. The power supply unit 40 has power supply terminals 41, 41. DC wiring 51, 51 supplies power to the output of the DC power supply unit 20. AC wiring 52, 52 supplies power to the output of the DC / AC converter 30.

[0023] The power input terminals 21, 21 of the DC power supply unit 20 and the two output terminals of the system power supply GPS are connected via two power cables. The DC power supply unit 20 receives AC power from the system power supply GPS via the two power cables. The DC power supply unit 20 converts the AC power into DC power and outputs the converted DC power from the power output terminals 22, 22. The frequency of the output power of the system power supply GPS is, for example, 60Hz, and the voltage is, for example, 200V. The output voltage of the DC power supply unit 20 is, for example, 400V. However, the output power of the system power supply GPS and the voltage of the output power of the DC power supply unit 20 are not limited to those described above.

[0024] Each of the multiple DC / AC converters 30 is connected in parallel with the DC power supply unit 20. Specifically, each of the power output terminals 22, 22 of the DC power supply unit 20 is connected to each of the input terminals 31, 31 of the nearest DC / AC converter 30 to the DC power supply unit 20 via DC wiring 51, 51. Moreover, each of the input terminals 31, 31 of other DC / AC converters 30, not the nearest DC / AC converter 30, is connected to each of the input terminals 31, 31 of adjacent DC / AC converters 30 via DC wiring 51, 51. Thus, DC power is supplied from the same DC power supply unit 20 to the multiple DC / AC converters 30 connected to the DC wiring 51, 51.

[0025] The DC / AC converter 30 converts the DC power supplied from the DC power supply 20 into AC power of the operating frequency via DC wiring 51, 51, and outputs the converted AC power from output terminals 32, 32. The voltage value of the output power of the DC / AC converter 30 is, for example, 200V, but is not limited thereto.

[0026] Each of the plurality of power supply devices 40 is connected in parallel with the DC / AC converter 30. Specifically, each of the output terminals 32, 32 of the DC / AC converter 30 is connected to each of the power supply terminals 41, 41 of the nearest power supply device 40 to the DC / AC converter 30 via AC wiring 52, 52. Moreover, each of the power supply terminals 41, 41 of other power supply devices 40, not the nearest power supply device 40, is connected to each of the power supply terminals 41, 41 of adjacent power supply devices 40 via AC wiring 52, 52. Thus, AC power is supplied from the same DC / AC converter 30 to the plurality of power supply devices 40 connected to the AC wiring 52, 52.

[0027] The power transmission device 40 applies AC power supplied from the DC / AC converter 30 to the built-in power transmission coil L1 via AC wiring 52, 52. Figure 2 ), to provide non-contact power supply to the receiving device 80.

[0028] A2. Circuit structure of contactless power supply system: like Figure 2As shown, in addition to the above-described structure, the DC power supply device 20 also includes a line filter 23 and a PFC circuit 24. 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 after passing through the line filter 23 into DC power and outputs it. The PFC circuit 24 is a power factor improvement circuit with a circuit structure for making its own power factor close to 1. Specifically, the PFC circuit 24 includes a rectifier, a smoothing capacitor, etc. The PFC circuit 24 outputs the generated DC power from the power output terminals 22, 22.

[0029] In addition to the above-described structure, the DC / AC converter 30 also includes 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 unit 20 into AC power with 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 after passing through the high-frequency filter 34 is output from the output terminals 32, 32.

[0030] In addition to the above-described structure, the power transmission device 40 also includes a power transmission resonant circuit 44 and a switching circuit 46. The power transmission resonant circuit 44 includes a power transmission coil L1, a power transmission capacitor C1, and a first switch SW1. The power transmission capacitor C1 functions to make the power transmission resonant circuit 44 resonant at its operating frequency and to make it non-resonant at its operating frequency. The power transmission capacitor C1 includes a first power transmission capacitor C11 and a second power transmission capacitor C12.

[0031] The first power supply capacitor C11 is connected in series with the power supply coil L1. The second power supply capacitor C12 is connected in series with the first switch SW1. Furthermore, the connection between the second power supply capacitor C12 and the first switch SW1 is connected in parallel with the first power supply capacitor C11. The first switch SW1 is a bidirectional switch connecting the source terminals of two FETs (Field Effect Transistors). The switching signal Sig1 output from the switching circuit 46 is input to the gate terminals of the two FETs. This controls the on / off state of the first switch SW1.

[0032] When a high-level switching signal Sig1 is input to the first switch SW1, the first switch SW1 becomes closed, i.e., conduction state, and current flows through the second power supply capacitor C12. When the first switch SW1 is closed, the power supply resonant circuit 44 becomes resonant through the first power supply capacitor C11, the second power supply capacitor C12, and the power supply coil L1. On the other hand, when a low-level switching signal Sig1 is input to the first switch SW1, the first switch SW1 becomes open, i.e., non-conducting state. Moreover, since the resonant frequency of the resonant circuit formed by the first power supply capacitor C11 and the power supply coil L1 deviates from the operating frequency, the power supply resonant circuit 44 becomes non-resonant.

[0033] like Figure 9 As shown, the power receiving device 80 includes a power receiving resonant circuit 81 having at least a power receiving coil L2. Additionally, in Figure 2 The power receiving device 80 is omitted in the text.

[0034] Figure 2 The switching circuit 46 shown detects the presence of a receiving coil L2 near the power supply coil L1. Figure 9 When the switching signal Sig1 is used, the first switch SW1 is switched from the open state to the closed state. This sets the power supply resonant circuit 44 to a resonant state. With the power supply coil L1 and the receiving coil L2 magnetically coupled, the resonant frequency of the power supply resonant circuit 44 and the resonant frequency of the receiving resonant circuit 81 are set to be approximately the same. Therefore, through the magnetic field coupling between the power supply coil L1 and the receiving coil L2, non-contact power supply can be provided to the receiving coil L2.

[0035] 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 Figure 1 As shown, DC power can be supplied from one DC power supply device 20 to multiple DC / AC conversion devices 30. Furthermore, in this embodiment, when an additional DC / AC conversion device 30 is added, each of the input terminals 31, 31 of the nearest DC / AC conversion device 30 is connected to each of the input terminals 31, 31 of the newly added DC / AC conversion device 30 via 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, it is possible to add a DC / AC conversion device 30 to an already installed DC power supply device 20.

[0036] The same applies to the power transmission device 40; the rated power of the DC / AC converter 30 is set to a value capable of supplying power to multiple power transmission devices 40. Therefore, for a DC / AC converter 30 that has already been installed, additional power transmission devices 40 can be connected.

[0037] As described above, when a DC / AC converter 30 is added, by connecting the new DC / AC converter 30 and the existing DC / AC converter 30 using DC wiring 51, 51, the new DC / AC converter 30 can receive power from the DC power supply device 20. Therefore, compared to connecting the new DC / AC converter 30 and the DC power supply device 20 using DC wiring 51, 51, the installation time required can be reduced. Similarly, when a power transmission device 40 is added, by connecting the new power transmission device 40 and the existing power transmission device 40 using AC wiring 52, 52, the installation time required can be reduced.

[0038] In this embodiment, when the contactless power supply device 10 has multiple power supply devices 40, by providing multiple DC / AC conversion devices 30 for a single DC power supply device 20, the difference in power supply efficiency between the multiple power supply devices 40 can be reduced. Assuming that AC power is supplied from one DC / AC conversion device 30 to all power supply devices 40 of the contactless power supply device 10, the total length of the AC wiring 52 tends to increase. The longer the AC wiring 52, the greater the parasitic components such as parasitic inductance and parasitic capacitance. Since the lengths of the AC wiring 52 differ between the power supply devices 40 close to and far from the DC / AC conversion device 30, the magnitudes of the parasitic components differ between the two. Therefore, since the impedance of the current path from the DC / AC conversion device 30 to the power supply coil L1 differs between the two, the current flowing through the power supply coil L1 for the AC power output from the DC / AC conversion device 30 also differs between the two. Therefore, the longer the total length of the AC wiring 52, the greater the difference in power supply efficiency between the two. To address this, according to this embodiment, when multiple power supply devices 40 are provided, DC power is distributed to multiple DC / AC conversion devices 30, and AC power is supplied from each DC / AC conversion device 30 to the power supply device 40. Thus, by distributing the range of power wiring from the DC power supply device 20 to the power supply device 40 between the range of DC wiring 51, 51 and the range of AC wiring 52, 52, the total length of the AC wiring 52, 52 can be shortened. Therefore, the difference in power supply characteristics between the multiple power supply devices 40 can be reduced.

[0039] Furthermore, to compensate for the impedance difference in the current path up to the power transmission coil L1 caused by the increased length of the AC wiring 52, 52, a structure for arranging a compensation capacitor unit between the DC / AC converter 30 and the power transmission device 40 is also considered. However, in this case, in addition to the DC / AC converter 30, a compensation capacitor unit is also required. In view of this, according to this embodiment, by not using a compensation capacitor unit, the increase in the number of components required to install the contactless power supply device 10 can be suppressed. In addition, AC losses are generated in the wiring for transmitting AC power. Moreover, in order to reduce AC losses, the wires used for AC wiring 52, 52 tend to be more expensive than the wires used for DC wiring 51, 51. In view of this, in this embodiment, by distributing the range of power wiring from the DC power supply device 20 to the power transmission device 40 between the range of DC wiring 51, 51 and the range of AC wiring 52, 52, the length of AC wiring 52, 52 can be shortened, and therefore, the installation cost can be reduced. Furthermore, by shortening the length of AC wiring 52, 52, AC losses can be reduced.

[0040] According to the first embodiment described above, the contactless power supply device 10 includes a DC power supply device 20 and a DC / AC conversion device 30. Furthermore, the rated power of the DC power supply device 20 is greater than the rated power of the DC / AC conversion device 30. Therefore, when adding a power transmission device 40, 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. Moreover, when multiple power transmission devices 40 are connected to one DC power supply device 20, the range of power wiring from the DC power supply device 20 to the power transmission devices 40 is distributed by the range of DC wiring 51, 51 and the range of AC wiring 52, 52. Compared to the case where AC wiring 52, 52 is used to wire from one DC / AC conversion device 30 to all power transmission devices 40, the length of the AC wiring 52, 52 can be shortened. Therefore, even when multiple power supply devices 40 are configured, the difference in distance between the DC / AC conversion device 30 and each power supply device 40 can be reduced, thus making it difficult to produce a difference in power supply efficiency caused by the increase in the length difference of AC wiring 52, 52.

[0041] B. Second implementation method: like Figure 3 As shown, the connection methods of the plurality of DC / AC conversion devices 30 and DC power supply devices 20 in the contactless power supply device 210 of the second embodiment are different from those in the first embodiment. Structures identical to those in the first embodiment are labeled with the same symbols, and detailed descriptions are omitted where appropriate.

[0042] In this embodiment, the furthest DC / AC converter 30E among the multiple DC / AC converters 30, which is the furthest DC / AC converter 30 from the DC power supply device 20, is connected to the DC power supply device 20 via DC wiring 51, 51. Furthermore, the other DC / AC converters 30 besides the furthest DC / AC converter 30E are connected using DC wiring 51, 51 branching off from the DC wiring 51, 51 that connects the DC power supply device 20 and the furthest DC / AC converter 30E. Specifically, connectors are installed at the branching points of the DC wiring 51, 51, and the branched DC wiring 51, 51 is connected to the connectors. Additionally, "farthest from the DC power supply device 20" refers to the location with the longest distance from the DC power supply device 20.

[0043] Similarly, the furthest power supply device 40 among the multiple power supply devices 40, which is the furthest power supply device 40 from the DC / AC converter 30, is connected to the DC / AC converter 30 via AC wiring 52, 52. Moreover, the other power supply devices 40 besides the furthest power supply device 40E are connected using AC wiring 52, 52 branching off from the AC wiring 52, 52 that connects the DC / AC converter 30 to the furthest power supply device 40E.

[0044] The length LE2 of the AC wiring 52, 52 connecting the power supply terminals 41, 41 of the power supply device 40 closest to the DC / AC converter 30 and the output terminals 32, 32 of the DC / AC converter 30 is shorter than the length LE1 of the DC wiring 51, 51 connecting the input terminals 31, 31 of the furthest DC / AC converter 30E and the power output terminal 22 of the DC power supply device 20. Furthermore, the length LE1 of the DC wiring 51, 51 refers to the length of the longer of the two DC wirings 51. The length LE2 of the AC wiring 52, 52 refers to the length of the longer of the two AC wirings 52. Additionally, "closest to the DC / AC converter 30" means the shortest distance to the DC / AC converter 30. By making the length LE2 shorter than the length LE1, the effect of reducing the difference in power supply efficiency can be further improved. In addition, when multiple power supply devices 40 are connected, in order to reduce the difference in power supply efficiency for all power supply devices 40, it is best to make the length of the AC wiring 52, 52 connecting the power supply device terminals 41, 41 of the farthest power supply device 40E to the output terminals 32, 32 of the DC / AC converter 30 shorter than the length LE1.

[0045] Furthermore, in practice, when multiple power supply devices 40 are installed, the aforementioned size relationship can be achieved by configuring the DC / AC converter 30 in a manner that satisfies the aforementioned size relationship between length LE2 and length LE1. That is, when the installation range of the predetermined multiple power supply devices 40 is wide, the installation range is divided, and the DC / AC converter 30 is configured for each divided installation range. Thus, the aforementioned size relationship between length LE2 and length LE1 can be satisfied.

[0046] According to the second embodiment described above, the same effect as the first embodiment can be achieved, and 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, the contactless power supply device 210 has multiple DC / AC conversion devices 30 and multiple power transmission devices 40. The DC power supply device 20 and the multiple DC / AC conversion devices 30 are connected via DC wiring 51, 51. The DC / AC conversion devices 30 and the multiple power transmission devices 40 are connected via AC wiring 52, 52. In this way, by distributing the range of power wiring from the DC power supply device 20 to the power transmission devices 40 between the range of DC wiring 51, 51 and the range of AC wiring 52, 52, the length of AC wiring 52, 52 can be shortened compared to the case where AC wiring 52, 52 is laid from one DC / AC conversion device 30 to all power transmission devices 40. Therefore, it is difficult for a difference in power supply efficiency to occur between the power transmission devices 40.

[0047] C. Third implementation method: like Figure 4 As shown, the contactless power supply device 310 of the third embodiment differs from the above embodiments in that it has a power supply control device 60. Structures identical to those in the above embodiments are labeled with the same reference numerals, and detailed descriptions are omitted where appropriate. In this embodiment, the contactless power supply device 310 is illustrated and explained in a manner that includes four DC / AC conversion devices 30.

[0048] The power supply control device 60 controls multiple DC / AC converters 30. The power supply control device 60 sends a synchronization signal Sig2 to each of the multiple DC / AC converters 30. Specifically, the power supply control device 60 and each DC / AC converter 30 are connected via a signal line 53 that transmits the synchronization signal Sig2.

[0049] The inverter 33 has four switching elements Q1, Q2, Q3, and Q4 that constitute a bridge circuit. In this embodiment, the switching elements Q1 to Q4 are implemented by MOSFETs (metal-oxide-semiconductor field-effect transistors).

[0050] As described above, the inverter control unit 35 drives the inverter 33. Specifically, the inverter control unit 35 inputs PWM control signals to the gate terminals of each of the switching elements Q1 to Q4 to set the switching elements Q1 to Q4 to an on or off state, respectively. The inverter control unit 35 sets the groups of switching elements Q1 and Q4, and the groups of switching elements Q2 and Q3 to an on or off state complementaryly. Specifically, during the period when the PWM control signal input to the switching elements Q1 and Q4 is an on-state 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-state voltage that sets the switching elements Q2 and Q3 to an off-state. Similarly, during the period when the PWM control signal input to the switching elements Q1 and Q4 is an off-state voltage, the PWM control signal input to the switching elements Q2 and Q3 is set to an on-state voltage. The PWM control signal periodically switches between either the on-voltage or the off-voltage. The inverter control unit 35 regulates the output voltage of the DC / AC converter 30 by adjusting the duty cycle, which is the ratio of the period of the output on-voltage to one cycle.

[0051] In this embodiment, the high-frequency filter 34 is a fourth-order filter composed of an inductor and a capacitor. However, the high-frequency filter 34 is not limited to a fourth-order filter; filters with other circuit structures can be used.

[0052] The inverter control unit 35 uses the received synchronization signal Sig2 to control the phase of the output power of the DC / AC converter 30. Specifically, the inverter control unit 35 controls the phase of the output voltage of the DC / AC converter 30. The power supply control unit 60 controls multiple DC / AC converters 30 such that the phases of the output power of at least two DC / AC converters 30 are different from each other. This suppresses currents flowing in the same phase through the multiple DC / AC converters 30, thus reducing the ripple in the output voltage of the DC power supply unit 20 preceding the DC / AC converter 30. Therefore, the smoothing capacitor in the PFC circuit 24 of the DC power supply unit 20 can be miniaturized. Furthermore, the EMC (Electromagnetic Compatibility) effects caused by ripple current flowing through the DC wirings 51 and 52 can be reduced.

[0053] In this embodiment, the output voltage waveforms of all DC / AC converters 30 connected to the DC power supply 20 are further controlled to be different from each other.

[0054] The DC / AC converter 30 is pre-labeled with a device number. In this embodiment, the device number of the DC / AC converter 30 with the shortest distance from the DC power supply device 20 is set to "1", and the device numbers are sequentially assigned integers, with the number increasing as the distance from the DC power supply device 20 increases. When the device number connected to the DC power supply device 20 is set to "N" (N is an integer greater than or equal to 1) and the total number of DC / AC converters 30 is set to "X" (X is an integer greater than or equal to 2), the power supply control device 60 controls the DC / AC converters so that the waveform of the output power of the Nth DC / AC converter 30 is a waveform whose phase deviates from a predetermined reference waveform by (N-1)π / X [rad]. (N-1)π / X is also called the phase correction value. In this embodiment, the waveform of the output voltage of the DC / AC converter 30 with device number "1" is set to the predetermined reference waveform.

[0055] like Figure 5 As shown, the output voltage of the inverter 33 built into the DC / AC converter 30 (device number "1") is a rectangular wave with a phase of 0 rad and a period of Ts[s] at time ts. Since the waveform of the output voltage of the inverter 33 built into the DC / AC converter 30 (device number "2") is N=2 and X=4, this waveform is offset by (1π / 4)[rad] relative to the reference waveform. That is, this waveform is a rectangular wave with a phase of 0 rad at time (ts+Ts / 8). Similarly, the waveform of the output voltage of the inverter 33 built into the DC / AC converter 30 (device number "3") is offset by (1π / 2)[rad] relative to the reference waveform. The waveform of the output voltage of the inverter 33 built into the DC / AC converter 30 (device number "4") is offset by (3π / 4)[rad] relative to the reference waveform. Thus, the phases of the output voltage waveforms of all the DC / AC converters 30 connected to the DC power supply 20 are different from each other. Therefore, since the phases of the output currents of the four DC / AC converters 30 are the same, the ripple of the output voltage of the preceding DC power supply 20 can be further reduced.

[0056] In this embodiment, the power supply control device 60 sends a device number and a phase correction value to each DC / AC converter 30. The DC / AC converter 30 stores the received device number and phase correction value in a built-in (not shown) memory of the inverter control unit 35. Then, the inverter control unit 35 uses the phase correction value and the synchronization signal Sig2 to drive the inverter 33. Alternatively, as another embodiment of the method for setting the device number and phase correction value, the device number and phase correction value may be set by an operator in the DC / AC converter 30, rather than through communication between the power supply control device 60 and the DC / AC converter 30. Alternatively, instead of the phase correction value, a time correction value of "(N-1)Ts / (2X)" may be sent. The time correction value refers to the time difference between the reference time when the phase of the reference waveform is 0 rad and the time when the phase of its own output waveform is 0 rad.

[0057] In this embodiment, the case where the phases of the waveforms of the output voltages of all DC / AC converters 30 connected to the DC power supply 20 are controlled to be different from each other is described. However, it is not limited to this; it is also possible to configure the output voltage waveforms of at least two of the plurality of DC / AC converters 30 connected to the DC power supply 20 to be different from each other. Even in the case where multiple DC / AC converters 30 have output voltages with the same phase, the ripple of the output voltage of the DC power supply 20 can be reduced compared to the case where all DC / AC converters 30 have output voltages with the same waveform. As in this embodiment, if the phases of the waveforms of the output voltages of all DC / AC converters 30 connected to the DC power supply 20 are different from each other, the effect of reducing the ripple of the output voltage of the DC power supply 20 can be improved, and therefore, this is preferred.

[0058] The third embodiment described above achieves the same effect as the first embodiment. Furthermore, the power supply control device 60 controls the plurality of DC / AC converters 30 such that the phases of the output power of at least two of the DC / AC converters 30 are different from each other. Therefore, the ripple in the output voltage of the DC power supply device 20 can be reduced. Moreover, the power supply control device controls the plurality of DC / AC converters 30 such that the waveform of the output power of the Nth DC / AC converter 30 is a waveform with a phase offset by a phase correction value relative to a reference waveform. This improves the effect of reducing the ripple in the output voltage of the DC power supply device 20.

[0059] D. Fourth Implementation Method: In the third embodiment, signal lines 53, 53 are used for communication between the power supply control device 60 and the DC / AC conversion device 30. Figure 6 In this embodiment shown, the wireless communication between the power supply control device 60 and the DC / AC conversion device 30 differs from that in the third embodiment. Structures identical to those in the above embodiments are labeled with the same reference numerals, and detailed descriptions are omitted where appropriate.

[0060] Figure 6 The inverter control unit 35 included in the contactless power supply device 410 of this embodiment has a communication unit (not shown). The inverter control unit 35 transmits a synchronization signal Sig2 via wireless communication with the power supply control device 60. According to this embodiment, the same effects as the above-described embodiments can be achieved, and the effort of laying signal lines 53, 53 can be saved. Therefore, the contactless power supply device 310 can be easily installed.

[0061] E. Fifth implementation method: Figure 7 The contactless power supply device 510 of this embodiment shown has two DC / AC conversion devices 30. Furthermore, it differs from the embodiments described above in that the output voltages of the two DC / AC conversion devices 30 are different from each other. Structures identical to those in the embodiments described above are labeled with the same reference numerals, and detailed descriptions are omitted where appropriate.

[0062] One of the two DC / AC converters 30 is designated as First DC / AC Converter 30A, and the other is designated as Second DC / AC Converter 30B. First DC / AC Converter 30A and Second DC / AC Converter 30B are located in different areas. The two DC / AC converters 30 correspond to each of two types of power receiving devices 80 that require different power. One of the two types of power receiving devices 80 is designated as First Power Receiving Device 80A, and the other is designated as Second Power Receiving Device 80B. A power supply device 40 that provides contactless power to First Power Receiving Device 80A is also referred to as First Power Supply Device 40. A power supply device 40 that provides contactless power to Second Power Receiving Device 80B is also referred to as Second Power Supply Device 40. The power requirements of First Power Receiving Device 80A and Second Power Receiving Device 80B are different. Specifically, the maximum power requirement of First Power Receiving Device 80A is greater than the maximum power requirement of Second Power Receiving Device 80B. The first DC / AC converter 30A supplies AC power to the first power supply device 40, which provides contactless power supply to the first power receiving device 80A. The second DC / AC converter 30B supplies AC power to the second power supply device 40, which provides contactless power supply to the second power receiving device 80B.

[0063] The first power receiving device 80A is installed on an industrial robot fixed at its installation location. Since the relative position of the first power receiving device 80A to the first power supply device 40 remains constant, it can always receive contactless power supply. In contrast, the second power receiving device 80B is installed on a movable AGV. The relative position of the second power receiving device 80B to the second power supply device 40 changes. Therefore, the second power receiving device 80B can receive contactless power supply when it is within a position range where it can receive power from the second power supply device 40. Therefore, since the first power receiving device 80A can receive power evenly, the instantaneous power required is relatively small. In contrast, since the second power receiving device 80B cannot receive power evenly, the instantaneous power required is relatively large. Furthermore, the voltage value of the maximum power required by the second power receiving device 80B is greater than the voltage value of the maximum power required by the first power receiving device 80A.

[0064] The output voltage of the second DC / AC converter 30B is greater than the output voltage of the first DC / AC converter 30A. Therefore, the first DC / AC converter 30A and the second DC / AC converter 30B can respectively supply the required power to the receiving device 80, which is supplied non-contactly by each of its connected power supply devices 40, without any power shortage.

[0065] Specifically, the first DC / AC converter 30A and the second DC / AC converter 30B adjust their output voltages by regulating the duty cycle of the PWM control signal. That is, the maximum duty cycle of the PWM control signal of the first DC / AC converter 30A is set to be smaller than the maximum duty cycle of the PWM control signal of the second DC / AC converter 30B.

[0066] According to the fifth embodiment described above, it has the same effects as the embodiments described above. Furthermore, the contactless power supply device 510 includes a first DC / AC converter 30A and a second DC / AC converter 30B. Moreover, the maximum duty cycle of the PWM control signal of the first DC / AC converter 30A is set to be smaller than the maximum duty cycle of the PWM control signal of the second DC / AC converter 30B. Therefore, it is possible to supply power to multiple power receiving devices 80 with different power requirements, satisfying the power requirements of each power receiving device 80.

[0067] F. Sixth Implementation Method: In the fifth embodiment, the output voltage is adjusted by regulating the duty cycle of the PWM control signal output by the inverter control unit 35. In this embodiment, the output voltage of the DC / AC converter 30 is adjusted by regulating the impedance of the high-frequency filter 34 of the DC / AC converter 30, which differs from the fifth embodiment. Structures identical to those in the above embodiments are labeled with the same reference numerals, and detailed descriptions are omitted where appropriate. Specifically, the circuit structure of the DC / AC converter 30 is similar to... Figure 4 The third embodiment shown is the same, therefore, using Figure 4 The accompanying reference numerals are used for explanation. The structure of the contactless power supply device 510 is similar to... Figure 7 The fifth embodiment shown is the same, therefore, using Figure 7 The accompanying figure labels are explained.

[0068] In this embodiment, similar to the fifth embodiment, the contactless power supply device 510 includes: a first DC / AC conversion device 30A, which is connected to a first power supply device 40 that provides contactless power to the first power receiving device 80A; and a second DC / AC conversion device 30B, which is connected to the second power supply device 40 that provides contactless power to the second power receiving device 80B. The voltage value of the maximum power required by the second power receiving device 80B is greater than the voltage value of the maximum power required by the first power receiving device 80A.

[0069] In this embodiment, the impedances of the high-frequency filter 34 in the first DC / AC converter 30A and the high-frequency filter 34 in the second DC / AC converter 30B are different. Specifically, the impedance of the high-frequency filter 34 in the first DC / AC converter 30A is set such that the fundamental component of the output voltage of the first DC / AC converter 30A is smaller than the fundamental component of the output voltage of the second DC / AC converter 30B. Therefore, the output voltage of the second DC / AC converter 30B can be greater than the output voltage of the first DC / AC converter 30A.

[0070] The sixth embodiment described above can achieve the same effect as the embodiments described above.

[0071] G. Seventh Implementation Method: In the fifth embodiment, the output voltage is adjusted by regulating the duty cycle of the PWM control signal output by the inverter control unit 35. Figure 8The contactless power supply device 710 of this embodiment differs from the fifth embodiment in that the output voltage of the DC / AC converter 30 is adjusted by adjusting the turns ratio of the transformer 36 included in the DC / AC converter 730. Structures identical to those in the above embodiments are labeled with the same reference numerals, and detailed descriptions are omitted where appropriate.

[0072] like Figure 8 As shown, the DC / AC converter 730, in addition to the above-described structure, also includes a transformer 36. The transformer 36 is positioned between the inverter 33 and the high-frequency filter 34. The transformer 36 steps down or steps up the output voltage of the inverter 33. The output power of the transformer 36 is input to the high-frequency filter 34. Furthermore, in this embodiment, the high-frequency filter 34 is composed of coils and capacitors connected in series with each of the two power lines, and coils and capacitors connected between the two power lines.

[0073] In this embodiment, similar to the fifth embodiment, the contactless power supply device 510 includes: a first DC / AC conversion device 30A, which is connected to a first power supply device 40 that provides contactless power to the first power receiving device 80A; and a second DC / AC conversion device 30B, which is connected to the second power supply device 40 that provides contactless power to the second power receiving device 80B. The voltage value of the maximum power required by the second power receiving device 80B is greater than the voltage value of the maximum power required by the first power receiving device 80A.

[0074] In this embodiment, the turns ratio of the transformer 36 in the first DC / AC converter 30A and the turns ratio of the transformer in the second DC / AC converter 30B are different from each other. Specifically, the turns ratio of the transformer 36 in the first DC / AC converter 30A is greater than the turns ratio of the transformer in the second DC / AC converter 30B. Therefore, the output voltage of the second DC / AC converter 30B can be greater than the output voltage of the first DC / AC converter 30A.

[0075] The seventh embodiment described above can achieve the same effect as the embodiments described above.

[0076] H. Eighth Implementation Method: In the first embodiment described above, the power supply device 40 has a power supply resonant circuit 44, and the power supply coil L1 of the power supply resonant circuit 44 is used for non-contact power supply. Figure 9 As shown, the circuit structure of the power supply device 840 in this embodiment differs from that of the power supply device 40. Structures identical to those in the above embodiments are labeled with the same symbols, and detailed descriptions are omitted where appropriate.

[0077] In addition to the structure described above, the power transmission device 840 also includes a triple resonant circuit 48. The triple resonant circuit 48 is used to form or disconnect the power transmission path between the power transmission device 40 and the power receiving device 80. The triple resonant circuit 48 includes a triple coil L3, a triple capacitor C3, and a second switch SW2. The triple capacitor C3 and the second switch SW2 are connected in parallel with the triple coil L3. The second switch SW2 is a bidirectional switch identical to the first switch SW1. The triple coil L3 is positioned to magnetically couple with the power transmission coil L1. Thus, when the power transmission coil L1 is magnetically coupled to the power receiving coil L2, the power transmission coil L1, the power receiving coil L2, and the triple coil L3 are magnetically coupled to each other.

[0078] The capacitance value of the tertiary capacitor C3 is set to the value that, when the transmitting coil L1, receiving coil L2, and tertiary coil L3 are magnetically coupled to each other, the parallel resonant circuit formed by the tertiary coil L3 and the tertiary capacitor C3 becomes resonant.

[0079] The power receiving device 80 is installed on the mobile body in the same manner as in the first embodiment. When the power receiving coil L2 approaches the power supply coil L1, the switching circuit 46 switches the power supply resonant circuit 44 and the triple resonant circuit 48 from a non-resonant state to a resonant state, and switches the power supply device 40 from a standby state to a power supply state. Specifically, as described above, the switching circuit 46 switches the first switch SW1 from an open state to an on state, and switches the second switch SW2 from an on state to an open state. When the second switch SW2 is switched to the open state, the parallel resonant circuit formed by the triple coil L3 and the triple capacitor C3 becomes resonant. As a result, the power supply current flows through the power supply coil L1, and non-contact power is supplied to the power receiving coil L2.

[0080] Conversely, when the receiving coil L2 is far from the supply coil L1, the switching circuit 46 switches the supply resonant circuit 44 and the third resonant circuit 48 from a resonant state to a non-resonant state, and switches the power supply 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, the two terminals of the third coil L3 are short-circuited, therefore, the third resonant circuit 48 becomes a non-resonant state. Thus, the power supply device 40 is switched to a standby state where a standby current smaller than the supply current flows in the supply coil L1.

[0081] The power supply coils L1 are arranged in a grid, and the receiving coil L2 receives power from the nearest power supply coil L1 in the grid. That is, the multiple power supply coils L1 are sequentially switched from standby state to power supply state according to their configuration order. Therefore, it is possible that the magnetic flux generated by the power supply coil L1 of the power supply device 40 set to power supply state may pass through the adjacent power supply coil L1 of the power supply device 40 set to standby state. Here, by setting the triple resonant circuit 48 to a non-resonant state, the magnetic flux generated in the power supply coil L1 can be reduced.

[0082] The eighth embodiment described above can achieve the same effect as the embodiments described above.

[0083] I. Ninth Implementation Method: The power supply device 940 in this embodiment has a different circuit structure than the power supply device 840 in the eighth embodiment described above. Structures identical to those in the above embodiments are labeled with the same symbols, and detailed descriptions are omitted where appropriate.

[0084] like Figure 10 As shown, the power transmission device 940 has a triple resonant circuit 948. In addition to the triple coil L3, the triple capacitor C3, and the second switch SW2, the triple resonant circuit 948 also has a fourth capacitor C4 and a third switch SW3. The fourth capacitor C4 is connected in series with the third switch SW3. Furthermore, the connection between the fourth capacitor C4 and the third switch SW3 is connected in parallel with the triple coil L3. The third switch SW3 is implemented by a FET.

[0085] The third switch SW3 is set to the on state when the triple resonant circuit 848 is set to the resonant state, and to the off state when the triple resonant circuit 848 is set to the non-resonant state. Furthermore, the combined capacitance of the triple capacitor C3 and the fourth capacitor C4 is set such that, when the transmitting coil L1, receiving coil L2, and triple coil L3 are magnetically coupled to each other, the parallel resonant circuit formed by the triple coil L3, triple capacitor C3, and fourth capacitor C4 reaches a value that corresponds to the resonant state.

[0086] When the power supply device 840 is set to standby mode, the switching circuit 46 sets the first switch SW1 to the off state, the second switch SW2 to the on state, and the third switch SW3 to the off state. Conversely, when the power supply device 840 is set to power supply mode, the switching circuit 46 sets the first switch SW1 to the on state, the second switch SW2 to the off state, and the third switch SW3 to the on state. The triple resonant circuit 848, compared to the triple resonant circuit 48 of the eighth embodiment described above, adds a third switch SW3 and a fourth capacitor C4. Therefore, not only can the on / off state of the second switch SW2 be set, but the resonant / non-resonant state of the triple resonant circuit 948 can also be set by setting the on / off state of the third switch SW3. Thus, for example, even in the event of a fault where the second switch SW2 is always off, the triple resonant circuit 948 can be set to a non-resonant state using the third switch SW3.

[0087] The ninth embodiment described above can achieve the same effect as the embodiments described above.

[0088] J. Other implementation methods: (J1) In the first embodiment described above, in the power transmission resonant circuit 44, the power transmission capacitor C1 is connected in series with the power transmission coil L1. The circuit structure of the power transmission resonant circuit 44 and the circuit structure of the power receiving resonant circuit 81 are not particularly limited. For example, it could be a circuit structure of the so-called SS type, in which the power transmission capacitor C1 is connected in series with the power transmission coil L1 in the power transmission resonant circuit 44, and the power receiving capacitor is connected in series with the power receiving coil L2 in the power receiving resonant circuit 81. (a) Alternatively, it could be a circuit structure of the so-called PS type, in which the power transmission capacitor C1 is connected in parallel with the power transmission coil L1 in the power transmission resonant circuit 44, and the power receiving capacitor is connected in series with the power receiving coil L2 in the power receiving resonant circuit 81. (b) Alternatively, it could be a circuit structure of the so-called P-SS type, in which, in addition to the power transmission capacitor C1 connected in series with the power transmission coil L1, a capacitor connected in parallel with the power transmission coil L1 is included, and two power receiving capacitors are connected in series at the two terminals of the power receiving coil L2 in the power receiving resonant circuit 81. (c) Alternatively, in addition to the power supply capacitor C1 connected in series with the power supply coil L1, a capacitor connected in parallel with the power supply coil L1 may also be included. In the power receiving resonant circuit 81, a so-called SP-PS circuit structure may be formed, including a first power receiving capacitor connected in series with the power receiving coil L2 and a second power receiving capacitor connected in parallel with the power receiving coil L2. (d) Alternatively, the power supply resonant circuit 44 may have a closed circuit formed by connecting the coil and the capacitor in series. The coil of this closed circuit is positioned so that it can be magnetically coupled to the power receiving coil L2 when the power supply coil L1 and the power receiving coil L2 are magnetically coupled. (e) Furthermore, the capacitor of the closed circuit may be connected in parallel with the coil instead of in series with it. (f) Alternatively, the power supply resonant circuit 44 may also include a coil connected in series with the power supply coil L1 and a capacitor connected in parallel with the coil. This coil is positioned so that it can be magnetically coupled to the power receiving coil L2 when the power supply coil L1 and the power receiving coil L2 are magnetically coupled.

[0089] (J2) In the third embodiment described above, the power supply control device 60 controls a plurality of DC / AC converters 30 such that the phases of the output power of at least two of the plurality of DC / AC converters 30 are different from each other. Alternatively, the power supply control device 60 may also control a plurality of DC / AC converters 30 such that the phases of the output power of the plurality of DC / AC converters 30 are the same as each other.

[0090] (J3) In the first embodiment described above, the switching elements Q1 to Q4 constituting the pulse generation circuit 82 are implemented using MOSFETs. In other embodiments, the switching elements Q1 to Q4 can also be implemented using other semiconductor elements, such as IGBTs (Insulated Gate Bipolar Transistors) with a return-current diode connected to them. The same applies to the first switch SW1, the second switch SW2, and the third switch SW3. Furthermore, the first switch SW1 and the second switch SW2 are not limited to bidirectional switches; they can also be unidirectional switches composed of a single switching element. The third switch SW3 can also be a bidirectional switch.

[0091] (J4) In the first embodiment described above, adjacent DC / AC converters 30 are connected to each other via DC wiring 51, 51. In the second embodiment described above, DC / AC converters 30 other than the furthest DC / AC converter 30E are connected using DC wiring 51, 51 branching off from the DC wiring 51, 51 that connects the DC power supply unit 20 to the furthest DC / AC converter 30E. As another way to connect the DC power supply unit 20 to each DC / AC converter 30, the DC power supply unit 20 and each DC / AC converter 30 may also be connected via a distributor such as a terminal block. Furthermore, multiple DC / AC converters 30 may be connected at the power output terminals 22, 22 of the DC power supply unit 20. Similarly, as another way to connect the DC / AC converter 30 to each power supply device 40, the DC / AC converter 30 and each power supply device 40 may also be connected via a distributor such as a terminal block. Furthermore, multiple power supply devices 40 may be connected at the output terminals 32, 32 of the DC / AC converter 30.

[0092] This disclosure is not limited to the embodiments and modifications described above, and can be implemented in various structures without departing from its spirit. For example, the technical features in the embodiments and modifications corresponding to the technical features described in the summary section can be appropriately replaced or combined to solve part or all of the above-described technical problems, or to achieve part or all of the above-described effects. In addition, if a certain technical feature is not described as essential in this specification, it can be appropriately deleted.

[0093] K: Other methods: The features of this disclosure are as follows.

[0094] (Method 1) A contactless power supply device (10, 210-710) provides contactless power supply to a receiving device (80), the contactless power supply device comprising: DC power supply device (20); DC wiring (51), the DC wiring supplies power to the output of the DC power supply device. At least one DC / AC conversion device (30, 730) connected to the aforementioned DC wiring. AC wiring (52), the aforementioned AC wiring supplies power to the output of the aforementioned DC / AC converter; and At least one power supply device (40, 840, 940) connected to the aforementioned AC wiring. The rated power of the aforementioned DC power supply device is greater than the rated power of the aforementioned DC / AC conversion device.

[0095] (Method 2) In the contactless power supply device described in Method 1, wherein, Including multiple of the aforementioned DC / AC conversion devices, Including multiple of the aforementioned power transmission devices, The aforementioned DC power supply device has a power output terminal (22) that is connected to the aforementioned DC wiring. The aforementioned multiple DC / AC conversion devices each have an input terminal (31) connected to the aforementioned DC wiring and an output terminal (32) connected to the aforementioned AC wiring. Each of the aforementioned power supply devices has a power supply device terminal (41) that is connected to the aforementioned AC wiring. The length of the AC wiring connecting the power supply terminal of the power supply device closest to the DC / AC converter among the plurality of power supply devices to the output terminal of the DC / AC converter is shorter than the length of the DC wiring connecting the input terminal of the DC / AC converter furthest from the DC power supply device among the plurality of DC / AC converter devices to the power output terminal of the DC power supply device.

[0096] (Method 3) In the contactless power supply device described in method 1 or 2, wherein, Including multiple of the aforementioned DC / AC conversion devices, It also includes a power supply control device for controlling the aforementioned multiple DC / AC conversion devices. The aforementioned power supply control device sends synchronization signals to the aforementioned multiple DC / AC conversion devices respectively. The aforementioned multiple DC / AC conversion devices each have an inverter (33) that outputs the aforementioned output power and an inverter control unit (35) that controls the aforementioned inverter. The inverter control unit uses the received synchronization signal to control the phase of the output power. The aforementioned power supply control device controls the aforementioned plurality of DC / AC converters such that the phases of the output power of at least two of the aforementioned DC / AC converters are different from each other.

[0097] (Method 4) In the contactless power supply device described in Method 3, wherein, The aforementioned power supply control device controls the aforementioned plurality of DC / AC conversion devices to, in order of proximity to the aforementioned DC power supply device, label each of the aforementioned plurality of DC / AC conversion devices with device numbering, set the device numbering to N (N is an integer greater than or equal to 1), and set the total number of the aforementioned plurality of DC / AC conversion devices to X (X is an integer greater than or equal to 2), such that the waveform of the output power of the Nth aforementioned DC / AC conversion device becomes a waveform with a phase deviation of (N-1)π / X [rad] relative to a predetermined reference waveform.

[0098] (Method 5) The contactless power supply device described in any of methods 1 to 4, wherein, Including multiple of the aforementioned DC / AC conversion devices, The aforementioned plurality of DC / AC conversion devices include: a first DC / AC conversion device, wherein the first DC / AC conversion device is connected to a first power supply device for contactless power supply to a first power receiving device; and a second DC / AC conversion device, wherein the second DC / AC conversion device is connected to a second power supply device for contactless power supply to a second power receiving device whose required maximum power is greater than that required by the first power receiving device. The aforementioned multiple DC / AC conversion devices each include: an inverter (33) that outputs the aforementioned output power; and an inverter control unit (35) that controls the inverter by inputting a PWM control signal to the inverter. The maximum duty cycle of the PWM control signal of the first DC / AC converter is less than the maximum duty cycle of the PWM control signal of the second DC / AC converter.

[0099] (Method 6) The contactless power supply device described in any of methods 1 to 5, wherein, Including multiple of the aforementioned DC / AC conversion devices, The aforementioned plurality of DC / AC conversion devices include: a first DC / AC conversion device connected to a first power supply device that provides contactless power to a first power receiving device; and a second DC / AC conversion device connected to a second power supply device that provides contactless power to a second power receiving device that requires a maximum power greater than that required by the first power receiving device. The aforementioned multiple DC / AC conversion devices each have an inverter (33) that outputs the aforementioned output power and a filter (34) connected to the downstream stage of the aforementioned inverter. The impedance of the filter in the first DC / AC converter is set such that the fundamental component of the output voltage of the first DC / AC converter is smaller than the fundamental component of the output voltage of the second DC / AC converter.

[0100] (Method 7) The contactless power supply device described in any of methods 1 to 6, wherein, Including multiple of the aforementioned DC / AC conversion devices, The aforementioned plurality of DC / AC conversion devices include: a first DC / AC conversion device connected to a first power supply device that provides contactless power to a first power receiving device; and a second DC / AC conversion device connected to a second power supply device that provides contactless power to a second power receiving device that requires a maximum power greater than that required by the first power receiving device. The aforementioned multiple DC / AC conversion devices each have an inverter (33) that outputs the aforementioned output power and a transformer (36) connected to the downstream of the aforementioned inverter. The turns ratio of the transformer in the first DC / AC conversion device is greater than the turns ratio of the transformer in the second DC / AC conversion device.

[0101] (Method 8) The contactless power supply device described in any of methods 1 to 7, wherein, The aforementioned DC power supply device has a PFC circuit (24), which is connected to the system power supply (GPS) and converts the AC power supplied from the system power supply into DC power and outputs it. The aforementioned DC / AC conversion device has an inverter (33) that converts the DC power output from the aforementioned PFC circuit into AC power. The aforementioned power transmission device includes: a power transmission resonant circuit (44), which has a power transmission coil (L1) and a power transmission capacitor (C1); and a switching circuit (46) that switches the state of the power transmission resonant circuit between a resonant state and a non-resonant state. Including multiple of the aforementioned DC / AC conversion devices, This includes multiple of the aforementioned power transmission devices.

Claims

1. A contactless power supply device (10, 210-710) provides contactless power supply to a receiving device (80), the contactless power supply device comprising: DC power supply device (20); DC wiring (51), the DC wiring supplies power to the output power of the DC power supply device; At least one DC / AC conversion device (30, 730) connected to the DC wiring. AC wiring (52), the AC wiring supplying power to the output power of the DC / AC converter; and At least one power supply device (40, 840, 940) connected to the AC wiring. The rated power of the DC power supply device is greater than the rated power of the DC / AC converter device.

2. The contactless power supply device as described in claim 1, characterized in that, Includes multiple of the aforementioned DC / AC conversion devices, Includes multiple of the aforementioned power transmission devices, The DC power supply device has a power output terminal (22) that is connected to the DC wiring. Each of the aforementioned DC / AC converters has an input terminal (31) connected to the DC wiring and an output terminal (32) connected to the AC wiring. Each of the power supply devices has a power supply device terminal (41) connected to the AC wiring. The length of the AC wiring connecting the power supply terminal of the power supply device closest to the DC / AC converter among the plurality of power supply devices to the output terminal of the DC / AC converter is shorter than the length of the DC wiring connecting the input terminal of the DC / AC converter furthest from the DC power supply device among the plurality of DC / AC converter devices to the power output terminal of the DC power supply device.

3. The contactless power supply device as described in claim 1, characterized in that, Includes multiple of the aforementioned DC / AC conversion devices, It also includes a power supply control device for controlling the plurality of the DC / AC conversion devices. The power supply control device sends synchronization signals to each of the multiple DC / AC conversion devices. Each of the aforementioned 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 uses the received synchronization signal to control the phase of the output power. The power supply control device controls a plurality of the DC / AC converters such that the phase of the output power of at least two of the plurality of DC / AC converters is different from that of each other.

4. The contactless power supply device as described in claim 3, characterized in that, The power supply control device controls a plurality of the DC / AC conversion devices to, in order of proximity to the DC power supply device, label each of the plurality of DC / AC conversion devices with device number N, and set the device number to X, such that the waveform of the output power of the Nth DC / AC conversion device is a waveform with a phase deviation of (N-1)π / X [rad] relative to a predetermined reference waveform, where N is an integer greater than or equal to 1 and X is an integer greater than or equal to 2.

5. The contactless power supply device as described in claim 1, characterized in that, Includes multiple of the aforementioned DC / AC conversion devices, The plurality of DC / AC conversion devices include: a first DC / AC conversion device connected to a first power supply device for contactless power supply to a first power receiving device; and a second DC / AC conversion device connected to a second power supply device for contactless power supply to a second power receiving device, wherein the maximum power required by the second power receiving device is greater than the maximum power required by the first power receiving device. Each of the aforementioned 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. The maximum duty cycle of the PWM control signal of the first DC / AC converter is less than the maximum duty cycle of the PWM control signal of the second DC / AC converter.

6. The contactless power supply device as described in claim 1, characterized in that, Includes multiple of the aforementioned DC / AC conversion devices, The plurality of DC / AC conversion devices include: a first DC / AC conversion device connected to a first power supply device that provides contactless power to a first power receiving device; and a second DC / AC conversion device connected to a second power supply device that provides contactless power to a second power receiving device, wherein the second power receiving device requires a greater maximum power than the first power receiving device. Each of the aforementioned DC / AC conversion devices has an inverter (33) that outputs the output power and a filter (34) connected to the subsequent stage of the inverter. The impedance of the filter of the first DC / AC converter is set such that the fundamental component of the output voltage of the first DC / AC converter is smaller than the fundamental component of the output voltage of the second DC / AC converter.

7. The contactless power supply device as described in claim 1, characterized in that, Includes multiple of the aforementioned DC / AC conversion devices, The plurality of DC / AC conversion devices include: a first DC / AC conversion device connected to a first power supply device that provides contactless power to a first power receiving device; and a second DC / AC conversion device connected to a second power supply device that provides contactless power to a second power receiving device, wherein the second power receiving device requires a greater maximum power than the first power receiving device. Each of the aforementioned DC / AC conversion devices has an inverter (33) that outputs the output power and a transformer (36) connected to the downstream of the inverter. The first DC / AC converter has a transformer with a greater turns ratio than the second DC / AC converter has a transformer with a greater turns ratio.

8. The contactless power supply device as described in claim 1, characterized in that, The DC power supply device has a PFC circuit (24) connected to the system power supply (GPS) and converts the AC power supplied from the system power supply into DC power for output. The DC / AC conversion device has an inverter (33) that converts the DC power output from the PFC circuit into AC power. The power transmission device includes: a power transmission resonant circuit (44) having a power transmission coil (L1) and a power transmission capacitor (C1); and a switching circuit (46) that switches the state of the power transmission resonant circuit between a resonant state and a non-resonant state. Includes multiple of the aforementioned DC / AC conversion devices, It includes multiple of the aforementioned power transmission devices.

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