Contactless power supply system and transport system

Abstract

In a non-contact power supply system 110, each of a plurality of non-contact power supply devices 1A, 1B, 1C, 1D, 1E has a filter circuit 9 including a reactor and a capacitor and connected to an inverter 8 which converts power supplied from a power source 2 into AC power. The non-contact power supply system 110 is provided with: an electrostatic coupling unit 112 which electrostatically couples one non-contact power supply device and another non-contact power supply device and has two capacitors C10, C20 electrically connected in parallel; and different-phase coils 114 which are respectively provided between the filter circuit 9 of one non-contact power supply device and the two capacitors C10, C20 and which have inductance components for when a short circuit or a ground fault occurs.

Description

[Technical Field]

[0001] The present invention relates to a contactless power supply system and a transport system. [Background technology]

[0002] A known example of a conventional contactless power transfer system is the system described in Patent Document 1. The contactless power transfer system described in Patent Document 1 includes a power receiving unit configured to receive power contactlessly from a power transmitting device via a magnetic field, a rectifier circuit configured to rectify the AC power received by the power receiving unit, a pair of DC power lines connected to the DC output side of the rectifier circuit, a grounding member, a pair of bypass capacitors electrically connected between the pair of DC power lines and the grounding member, and a zero-phase-sequence current transformer configured to detect a difference in current flowing through the pair of power lines, the zero-phase-sequence current transformer being positioned to detect a difference in current flowing through the pair of DC power lines between the rectifier circuit and the pair of bypass capacitors. The contactless power transfer system described in Patent Document 1 detects a ground fault in the power receiving unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-108258 Summary of the Invention [Problem to be solved by the invention]

[0004] In a contactless charging system, a short circuit or a ground fault can occur due to installation errors, component failure, or the like. When a short circuit or a ground fault occurs, a large current such as a short circuit current or a ground fault current flows, and if this large current flows into a device such as an inverter, the device may be damaged. Therefore, circuit breakers such as fuses and breakers are usually used to prevent large currents from flowing into the device. However, there are few circuit breakers that can be used for high-frequency currents (e.g., 9 kHz) used in contactless power transfer systems, and such circuit breakers are expensive.

[0005] An object of one aspect of the present invention is to provide a contactless power supply system and a transportation system that can suppress a large current from flowing when a short circuit or a ground fault occurs. [Means for solving the problem]

[0006] A contactless power supply system according to one aspect of the present invention is a contactless power supply system including a plurality of contactless power supply devices, each of which is connected to an inverter that converts power supplied from a power source into AC power, and has a filter circuit including a reactor and a capacitor, and an electrostatic coupling unit that electrostatically couples one contactless power supply device to another contactless power supply device, the electrostatic coupling unit having two capacitors electrically connected in parallel, and an out-of-phase coil that is provided between the filter circuit of one contactless power supply device and each of the two capacitors of the electrostatic coupling unit, and has an inductance component when a short circuit or ground fault occurs.

[0007] A contactless power transfer system according to one aspect of the present invention includes out-of-phase coils that are provided between a filter circuit of one contactless power transfer device and each of two capacitors of a capacitive coupling unit, and that have an inductance component when a short circuit or ground fault occurs. Even when a short circuit or ground fault occurs, the out-of-phase coils have an inductance component (impedance, resistance component), so that the short-circuit current or ground fault current is limited by the out-of-phase coils. Therefore, the contactless power transfer system can prevent a large current from flowing when a short circuit or ground fault occurs. As a result, the contactless power transfer system can prevent the inverter from being damaged by a large current.

[0008] In one embodiment, each of the plurality of contactless power supply devices is a device that supplies a high-frequency current, and the different-phase coils may have an inductance component in the high-frequency current. In this configuration, since the different-phase coils have an inductance component in the high-frequency current, it is possible to suppress a large current from flowing in a contactless power supply system that uses a high-frequency current.

[0009] In one embodiment, the contactless power supply system includes a plurality of power feeders provided along a track rail on which traveling vehicles travel, and each of the plurality of contactless power supply devices wirelessly supplies power to the traveling vehicles traveling on the track rail. Each of the plurality of contactless power supply devices has a designated area for supplying AC power, and each of the plurality of power feeders may be provided in a corresponding area. In this configuration, the contactless power supply system includes an electrostatic coupling unit that electrostatically couples one contactless power supply device to another contactless power supply device. As a result, in the contactless power supply system, even if, for example, one contactless power supply device is unable to supply AC power to one power feeder, the other contactless power supply device can supply AC power to the one power feeder. In this way, the contactless power supply system can supply AC power to power feeders outside its designated area by the electrostatic coupling unit that electrostatically couples one contactless power supply device to another contactless power supply device. This allows traveling vehicles to travel on the track rail.

[0010] In one embodiment, the contactless power supply system may include a switching unit that switches between a coupled state and a non-coupled state of the electrostatic coupling between one contactless power supply device and another contactless power supply device. In this configuration, the electrostatic coupling between the one contactless power supply device and another contactless power supply device can be switched between a coupled state and a non-coupled state as desired.

[0011] A transportation system according to one aspect of the present invention includes the above-described contactless power supply system and a traveling vehicle that travels by receiving power transmitted from the contactless power supply system.

[0012] A transportation system according to one aspect of the present invention includes the above-described contactless power supply system, and therefore, in the transportation system, it is possible to suppress a large current from flowing when a short circuit or a ground fault occurs. [Effects of the Invention]

[0013] According to one aspect of the present invention, it is possible to suppress a large current from flowing when a short circuit or a ground fault occurs. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram schematically illustrating a track of a transport system according to an embodiment. [Figure 2] FIG. 2 is a diagram showing the configuration of the transport system. [Figure 3] FIG. 3 is a diagram showing the configuration of a contactless power supply device. [Figure 4] FIG. 4 is a diagram showing the configuration of a contactless power supply system. [Figure 5] FIG. 5 is a diagram showing a short-circuit point when a short circuit occurs. [Figure 6] FIG. 6 is a diagram showing a ground fault point when a ground fault occurs. [Figure 7] FIG. 7 is a diagram showing the configuration of the ceiling transport vehicle. [Figure 8] FIG. 8 is a diagram showing the configuration of a contactless power supply system according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are designated by the same reference numerals, and redundant description will be omitted.

[0016] As shown in FIG. 1, the transport system 100 is a system for transporting articles using overhead transport vehicles (traveling vehicles) 120 that can move along a track rail T. The track rail T is a member that allows the overhead transport vehicles 120 to travel, and is suspended from the ceiling. In this embodiment, the track rail T is divided into multiple systems (bays) (five in the example of FIG. 1). The track rail T includes an intra-bay route (area) BR1, which is a travel path within a bay, and an inter-bay route (area) BR2, which is a travel path connecting different bays. The intra-bay route BR1 is set up so that the overhead transport vehicles 120 travel one-way in a clockwise direction. Like the intra-bay route BR1, the inter-bay route BR2 is also set up so that the overhead transport vehicles 120 travel one-way in a clockwise direction.

[0017] The conveyance system 100 includes a contactless power supply system 110 and an overhead transport vehicle 120. In the conveyance system 100, power is supplied to the overhead transport vehicle 120 in a contactless manner from power feeders 12A and 12B provided on a track rail T. The overhead transport vehicle 120 travels using the power supplied from the power feeders 12A and 12B. The overhead transport vehicle 120 drives various devices provided on the overhead transport vehicle 120 using the power supplied from the power feeders 12A and 12B.

[0018] The overhead transport vehicle 120 includes, for example, a ceiling-suspended crane, an OHT (Overhead Hoist Transfer), etc. The goods include, for example, a container for storing multiple semiconductor wafers, a container for storing glass substrates, a reticle pod, general parts, etc.

[0019] As shown in Fig. 2, the track rail T is, for example, a circuit track. Power is supplied to the power feeders 12A and 12B from the non-contact power feeders 1A, 1B, 1C, 1D, and 1E. The power feeders 12A and 12B are arranged below the track rail T in the traveling direction of the overhead transport vehicle 120, on at least one of the right and left sides of the track center. Note that the power feeder 12B is arranged below the power feeder 12A, and therefore overlaps the power feeder 12A in Fig. 2.

[0020] The arrangement of the power feeders 12A and 12B with respect to the track rail T is changed by the switching unit 30. In an initial area where the power feeders 12A and 12B are connected to the contactless power feeders 1A, 1B, 1C, 1D, and 1E, the power feeders 12A and 12B are arranged on the left side of the track rail T. When the overhead transport vehicle 120 travels on the track rail T in the traveling direction, the arrangement of the power feeders 12A and 12B is switched from the left side to the right side of the track rail T by the switching unit 30.

[0021] The contactless power supply system 110 includes contactless power supply devices 1A, 1B, 1C, 1D, and 1E. The contactless power supply devices 1A, 1B, 1C, 1D, and 1E supply power to the ceiling transport vehicle 120 in a contactless manner. The contactless power supply devices 1A, 1B, 1C, 1D, and 1E supply high-frequency current. The high frequency is, for example, 9 kHz. The contactless power supply devices 1A, 1B, 1C, 1D, and 1E are provided corresponding to the intra-bay route BR1 and the inter-bay route BR2, respectively. In this embodiment, the contactless power supply devices 1A, 1B, 1C, and 1D supply power to each intra-bay route BR1. The contactless power supply device 1E supplies power to the inter-bay route BR2. In this embodiment, the contactless power supply devices 1A, 1B, 1C, 1D, and 1E are housed in a housing 111.

[0022] 3, contactless power supply devices 1A, 1B, 1C, 1D, and 1E include a power supply 2, a molded case circuit breaker 3, a noise filter 4, a power factor correction device 5, a rectifier 6, a smoother 7, an inverter 8, a filter circuit 9, a first current sensor 10, a second current sensor 11, power supply lines 12A and 12B, and a control device 13. The noise filter 4, the power factor correction device 5, the rectifier 6, and the smoother 7 configure a power converter 16.

[0023] The power source 2 is a facility that supplies AC power such as a commercial power source, and supplies AC power (three-phase 200V). The frequency of the AC power is, for example, 50 Hz or 60 Hz. The molded case circuit breaker 3 opens the electrical circuit when an overcurrent flows. The noise filter 4 removes noise from the AC power. The noise filter 4 is made up of, for example, a capacitor. The power factor correction device 5 improves the power factor by making the input current closer to a sine wave. The power factor correction device 5 is made up of, for example, a reactor.

[0024] The rectifier 6 converts AC power supplied from the power source 2 (power factor correction device 5) into DC power. The rectifier 6 is formed of a rectifying element such as a diode, for example. The rectifier 6 may be formed of a switching element such as a transistor. The smoother 7 smoothes the DC power converted by the rectifier 6. The smoother 7 is formed of an electrolytic capacitor, for example. The voltage converter may further have a step-up / step-down function.

[0025] The inverter 8 converts the DC power output from the smoother 7 into AC power and outputs it to the filter circuit 9. The inverter 8 changes the magnitude of the AC power output to the filter circuit 9 by changing the switching frequency based on a control signal output from the control device 13. The inverter 8 has a plurality of switching elements 14. The switching elements 14 are elements that can be electrically switched between open and closed. Examples of the switching elements 14 that can be used include MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), IGBTs (Insulated Gate Bipolar Transistors), and bipolar transistors.

[0026] The filter circuit 9 is provided between the inverter 8 and the power supply lines 12A and 12B. The filter circuit 9 suppresses harmonic noise. The filter circuit 9 includes a reactor RT1, a capacitor C0, a capacitor C1, a reactor RT2, and a capacitor C2.

[0027] The capacitor C0 and the reactor RT1 are connected in series to form a first resonant circuit RC1. The reactor RT1 is an out-of-phase coil. The reactor RT1 has an inductance component when a short circuit or a ground fault occurs. When a short circuit or a ground fault occurs, the inductance components of the reactor RT1 do not cancel each other out. The reactor RT1 has an inductance component (impedance, resistance component) in a high-frequency (e.g., 9 kHz) current (high-frequency current).

[0028] The reactor RT1 includes a coil L11 and a coil L12. The coil L11 is provided between the inverter 8 (capacitor C0) and a second resonant circuit RC2 (described later). The coil L12 is provided between the inverter 8 and the power supply lines 12A and 12B. The coils L11 and L12 are magnetically coupled. In the reactor RT1, the inductances of the coils L11 and L12 are set appropriately.

[0029] The reactor RT2 and the capacitor C2 are connected in series to form a second resonant circuit RC2. The first resonant circuit RC1 and the second resonant circuit RC2 are connected in series.

[0030] The reactor RT2 is a variable reactor whose reactor value is changeable (adjustable). The capacitor C2 is a variable capacitor whose capacitance value is changeable. The reactor value (parameter) of the reactor RT2 and the capacitance value (parameter) of the capacitor C2 are set (adjusted) by an operator, for example, when the equipment of the conveyance system 100 is installed. The capacitor C1 is connected in parallel to the first resonant circuit RC1 and the second resonant circuit RC2.

[0031] The first current sensor 10 detects a current I1 (inverter current) output from the inverter 8, i.e., flowing through the inverter 8. The first current sensor 10 outputs a first current signal indicating the detected current I1 to the control device 13. The second current sensor 11 detects a current I2 (supply current) of the AC power passing through the second resonant circuit RC2. The second current sensor 11 outputs a second current signal indicating the detected current I2 to the control device 13.

[0032] The power feeders 12A and 12B form coils for contactlessly feeding power to the power receiving unit 121 of the overhead transport vehicle 120. The power feeders 12A and 12B are, for example, Litz wires, and include multiple bundles each formed by twisting together several tens to several hundreds of copper wires. The outer periphery of the multiple twisted bundles is covered with, for example, a tube made of an insulating material. The power feeders 12A and 12B generate magnetic flux when AC power is supplied from the filter circuit 9. The power feeders 12A and 12B have an inductance RL. In this embodiment, the AC currents flowing through the multiple power feeders 12A and 12B are not synchronized in phase with each other.

[0033] The control device 13 controls the operation of the inverter 8. The control device 13 is a computer system or processor implemented in an integrated circuit. The control device 13 is composed of a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), etc., and an input / output interface, etc. Various programs and data are stored in the ROM.

[0034] The control device 13 has a control unit 15. The control device 13 is connected to the first current sensor 10 and the second current sensor 11 of the filter circuit 9. The control device 13 receives the first current signal and the second current signal output from the first current sensor 10 and the second current sensor 11, respectively.

[0035] The control unit 15 controls the inverter 8 to control the magnitude of the AC power supplied to the power feeders 12A and 12B, and thereby controls the magnitude of the power supplied to the overhead transport vehicle 120. In this embodiment, the power control is performed using phase shift control. In the phase shift control, a power control parameter for controlling the magnitude of the AC power is changed. The control unit 15 performs phase shift control to change the magnitude (frequency) of the AC power by changing the on-period of the inverter 8. The control unit 15 adjusts the switching frequency of each switching element 14 using drive signals to the multiple switching elements 14 of the inverter 8, and changes the on-period of each switching element 14. The power control parameter in the phase shift control is the on-period of each switching element 14 of the inverter 8.

[0036] The control unit 15 performs power control based on the first current signal and the second current signal output from the first current sensor 10 and the second current sensor 11, respectively, so that the value of the power transmitted to the ceiling transport vehicle 120 becomes a target value.

[0037] In the contactless power supply system 110, the contactless power supply devices 1A, 1B, 1C, 1D, and 1E are electrostatically coupled to one another. Fig. 4 shows an example of a configuration in which the contactless power supply device 1A and the contactless power supply device 1B are electrostatically coupled. As shown in Fig. 2 or 4, the contactless power supply system 110 further includes a housing 111, an electrostatic coupling unit 112, a switch (switching unit) 113, and an out-of-phase coil 114.

[0038] The housing 111 houses the contactless power supply devices 1A, 1B, 1C, 1D, and 1E. The housing 111 is installed at a predetermined position in the factory.

[0039] The electrostatic coupling unit 112 electrostatically couples the contactless power supply device 1A and the contactless power supply device 1B. The electrostatic coupling unit 112 is connected to output ends (ends connected to the power supply lines 12A and 12B) of the contactless power supply device 1A and the contactless power supply device 1B. The electrostatic coupling unit 112 includes a capacitor C10 and a capacitor C20. That is, the contactless power supply device 1A and the contactless power supply device 1B are electrostatically coupled by the capacitor C10 and the capacitor C20. The capacitor C10 and the capacitor C20 are electrically connected in parallel. The electrostatic coupling unit 112 is provided inside the housing 111. That is, the contactless power supply devices 1A, 1B, 1C, 1D, and 1E are electrostatically coupled to each other inside the housing 111. In this embodiment, all of the contactless power supply devices 1A, 1B, 1C, 1D, and 1E are electrostatically coupled by the electrostatic coupling unit 112.

[0040] The electrostatic coupling unit 112 realizes the supply of AC current from the contactless power supply device 1A to the power feed lines 12A and 12B of the contactless power supply device 1B, or the supply of AC current from the contactless power supply device 1B to the power feed lines 12A and 12B of the contactless power supply device 1A. In the electrostatic coupling unit 112, the capacitances of the capacitors C10 and C20 are set appropriately. In this embodiment, the impedance of the electrostatic coupling unit 112 is set to be equal to the impedance of the second resonant circuit RC2 (the power feed lines 12A and 12B) when viewed from the overhead transport vehicle 120 side (power receiving side) to which power is supplied. That is, the impedance of the electrostatic coupling unit 112 and the impedance of the power feed lines 12A and 12B resonate with each other.

[0041] The switch 113 switches between a coupled state and a non-coupled state of electrostatic coupling between one contactless power supply device and another contactless power supply device. That is, in the example shown in Fig. 4, the switch 113 switches ON / OFF the supply of AC current from the contactless power supply device 1A to the power supply lines 12A and 12B of the contactless power supply device 1B, or the supply of AC current from the contactless power supply device 1B to the power supply lines 12A and 12B of the contactless power supply device 1A. The switch 113 is, for example, a breaker, a magnet conductor, a semiconductor element such as an IGBT, or the like.

[0042] In the contactless power supply system 110, when the AC power supplied from one contactless power supply device to one of the power supply lines 12A and 12B drops (the voltage drops), another contactless power supply device supplies AC power to the one of the power supply lines 12A and 12B. In the contactless power supply system 110, when the switch 113 is turned OFF, the supply of AC power from the contactless power supply devices 1A, 1B, 1C, 1D, and 1E to the power supply lines 12A and 12B of the other systems is stopped.

[0043] The out-of-phase coil 114 has an inductance component when a short circuit or a ground fault occurs. When a short circuit or a ground fault occurs, the inductance components of the out-of-phase coil 114 do not cancel each other out. The out-of-phase coil 114 has an inductance component (impedance, resistance component) in a high-frequency (e.g., 9 kHz, etc.) current (high-frequency current). The out-of-phase coil 114 is provided between the filter circuit 9 of one contactless power supply device and the electrostatic coupling unit 112. That is, the out-of-phase coil 114 is provided between the filter circuit 9 of one contactless power supply device and each of the two capacitors (capacitor C10 and capacitor C20). In the example shown in FIG. 4, the out-of-phase coil 114 is provided between the filter circuit 9 of the contactless power supply device 1A and capacitor C10 and capacitor C20.

[0044] The hetero-phase coil 114 includes a coil L10 and a coil L20. The coil L10 is provided between the contactless power supply device 1A and the capacitor C10 of the electrostatic coupling unit 112. The coil L20 is provided between the contactless power supply device 1A and the capacitor C20. The coils L10 and L20 are magnetically coupled. In the hetero-phase coil 114, the inductances of the coils L10 and L20 are set appropriately.

[0045] FIG. 5 is a diagram showing short-circuit points when a short circuit occurs. FIG. 5 shows a state in which short circuits occur at short-circuit points P1, P2, and P3. As shown in FIG. 5, when a short circuit occurs at short-circuit point P1, the short-circuit current is I short1 , the voltage of inverter 8 is V inv, when the inductance of each of the coils L11 and L12 of the reactor RT1 is L1, the short-circuit current I short1 becomes:

number

[0046] When a short circuit occurs at short circuit point P2, the short circuit current is I short2 , the voltage of inverter 8 is V inv When the inductance of each of the coils L11 and L12 of the reactor RT1 is L1, and the inductance of each of the coils L10 and L20 of the out-of-phase coil 114 is L2, the short-circuit current I short2 becomes:

number

[0047] When a short circuit occurs at short circuit point P3, the short circuit current is I short3 , the voltage of inverter 8 is V inv When the inductance of each of the coils L11 and L12 of the reactor RT1 is L1, the inductance of each of the coils L10 and L20 of the out-of-phase coil 114 is L2, and the capacitance of each of the capacitors C10 and C20 of the electrostatic coupling unit 112 is C, the short-circuit current I short3 becomes:

number

[0048] FIG. 6 is a diagram showing the ground fault points when a ground fault occurs. FIG. 6 shows a state in which a ground fault occurs at a ground fault point P11, a ground fault point P12, and a ground fault point P13. As shown in FIG. 6, when a short circuit occurs at the ground fault point P11, the ground fault current is I short11 , the voltage of inverter 8 is V inv , when the inductance of the coil L12 of the reactor RT1 is L1, the earth fault current I short11 becomes:

number

[0049] When a short circuit occurs at the ground fault point P12, the ground fault current is I short12 , the voltage of inverter 8 is V inv , when the inductance of the coil L12 of the reactor RT1 is L1 and the inductance of the coil L10 of the out-of-phase coil 114 is L2, the earth fault current I short12 becomes:

number

[0050] When a short circuit occurs at the ground fault point P13, the ground fault current is I short13 , the voltage of inverter 8 is V inv When the inductance of the coil L12 of the reactor RT1 is L1, the inductance of the coil L10 of the out-of-phase coil 114 is L2, and the capacitance of each of the capacitors C10 and C20 of the electrostatic coupling unit 112 is C, the earth fault current I short13 becomes:

number

[0051] 1 and 2, the overhead transport vehicle 120 travels along a track rail T to transport an article. The overhead transport vehicle 120 is configured to be able to transfer an article. The number of overhead transport vehicles 120 provided in the transport system 100 is not particularly limited and may be more than one.

[0052] As shown in FIG. 7, the ceiling transport vehicle 120 includes a power receiving unit 121, a driving device 122, a transfer device 123, and a control device .

[0053] The power receiving unit 121 receives power transmitted from the contactless power supply devices 1A, 1B, 1C, 1D, and 1E in a contactless manner. The power receiving unit 121 is a coil for receiving power. Magnetic flux generated by the power supply lines 12A and 12B interlinks with the power receiving unit 121, thereby generating AC power in the power receiving unit 121. The power receiving unit 121 supplies the AC power to the driving device 122 and the transfer device 123. A capacitor and a reactor may be connected between the power receiving unit 121 and the driving device 122 and the transfer device 123.

[0054] The driving device 122 drives and rotates a plurality of wheels (not shown). The driving device 122 is, for example, an electric motor or a linear motor, and uses power supplied from the power receiving unit 121 as power for driving.

[0055] The transfer device 123 can hold and store the items to be transported, and transfers the items. The transfer device 123 is equipped with, for example, a side-discharge mechanism that holds and protrudes the items, and a lifting mechanism that moves the items downward, and by driving the side-discharge mechanism and the lifting mechanism, the items are delivered to a load port of a storage device such as a stocker or a load port of a processing device, which is the transfer destination. The transfer device 123 uses power supplied from the power receiving unit 121 as power to operate.

[0056] The control device 124 controls the driving device 122 and the transfer device 123. The control device 124 uses the power supplied from the power receiving unit 121 as power for driving.

[0057] As described above, the conveyance system 100 according to this embodiment includes the contactless power supply system 110. The contactless power supply system 110 according to this embodiment includes the out-of-phase coils 114, which are provided between the filter circuit 9 of one contactless power supply device and each of the two capacitors C10 and C20 of the electrostatic coupling unit 112 and have an inductance component when a short circuit or a ground fault occurs. As a result, even when a short circuit or a ground fault occurs in the contactless power supply system 110, the out-of-phase coils 114 have an inductance component (impedance, resistance component), so that the short-circuit current or ground fault current is limited by the out-of-phase coils 114. Therefore, the contactless power supply system 110 can prevent a large current from flowing when a short circuit or a ground fault occurs. As a result, the contactless power supply system 110 can prevent the inverter 8 (switching element 14) from being damaged by a large current.

[0058] In the contactless power supply system 110 according to this embodiment, each of the plurality of contactless power supply devices 1A, 1B, 1C, 1D, and 1E is a device that supplies a high-frequency current to the power supply lines 12A and 12B. The different-phase coil 114 has an inductance component in the high-frequency current. In this configuration, since the different-phase coil has an inductance component in the high-frequency current, it is possible to suppress a large current from flowing in the contactless power supply system that uses a high-frequency current.

[0059] A contactless power supply system 110 according to this embodiment includes power supply lines 12A and 12B provided along a track rail T on which an overhead transport vehicle 120 travels. Each of a plurality of contactless power supply devices 1A, 1B, 1C, 1D, and 1E supplies power contactlessly to the overhead transport vehicle 120 traveling on the track rail T. Each of the plurality of contactless power supply devices 1A, 1B, 1C, 1D, and 1E has a set area to which AC power is supplied, and each of the plurality of power supply lines 12A and 12B is provided in the corresponding area. In this configuration, the contactless power supply system 110 includes an electrostatic coupling unit 112 that electrostatically couples one contactless power supply device to another contactless power supply device. As a result, in the contactless power feeding system 110, even if, for example, the contactless power feeding device 1A is unable to supply AC power to one of the power feed lines 12A, 12B, it is possible to supply AC power from the contactless power feeding device 1B to one of the power feed lines 12A, 12B. In this way, in the contactless power feeding system 110, AC power can be supplied to the power feed lines 12A, 12B outside the area under its jurisdiction by the electrostatic coupling unit 112 that electrostatically couples one of the contactless power feeding devices with another contactless power feeding device. This allows the overhead transport vehicle 120 to travel on the track rail T.

[0060] The contactless power supply system 110 according to this embodiment includes a switch 113 that switches between a coupled state and a non-coupled state of the electrostatic coupling between one contactless power supply device and another contactless power supply device. With this configuration, the electrostatic coupling between one contactless power supply device and another contactless power supply device can be switched between a coupled state and a non-coupled state as desired. Therefore, for example, when performing maintenance on one intra-bay route BR1, by turning off the switch 113 connected to the contactless power supply device of one intra-bay route BR1, it is possible to prevent power from being supplied to the ceiling transport vehicle 120 in the one intra-bay route BR1.

[0061] Although the embodiments of the present invention have been described above, the present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

[0062] In the above embodiment, an example has been described in which the hetero-phase coil 114 is provided between the contactless power supply device 1A and the electrostatic coupling unit 112. However, the hetero-phase coil 114 may be provided between any one of the plurality of contactless power supply devices 1A, 1B, 1C, 1D, and 1E and the electrostatic coupling unit 112.

[0063] In the above embodiment, an example has been described in which the contactless power supply system 110 includes the switch 113. However, as shown in Fig. 8, the contactless power supply system 110A does not necessarily include the switch 113. In this configuration, the contactless power supply devices 1A and 1B include a capacitor C3.

[0064] In the above embodiment, an example has been described in which all of the contactless power supply devices 1A, 1B, 1C, 1D, and 1E are electrostatically coupled by the electrostatic coupling unit 112. However, in the contactless power supply system 110, it is sufficient that at least two of the multiple contactless power supply devices 1A, 1B, 1C, 1D, and 1E are electrostatically coupled by the electrostatic coupling unit 112.

[0065] In the above embodiment, an example has been described in which the track rail T includes an intra-bay route BR1 and an inter-bay route BR2. However, the track rail T may be a single circular track. In this configuration, the single track rail T may be divided into a plurality of areas, and the contactless power supply devices 1A, 1B, 1C, 1D, and 1E may supply AC power to each area.

[0066] In the above embodiment, an example has been described in which the traveling vehicle is an overhead transport vehicle 120. However, the moving body is not limited to an overhead transport vehicle, and may be any traveling vehicle that travels on a track rail T. For example, the traveling vehicle may be a floor transport vehicle (floor traveling vehicle). When the traveling vehicle is a floor transport vehicle, the track rail is laid on the floor surface.

[0067] The technical subject matter of one aspect of the present invention can be described as follows. [1] A contactless power supply system including a plurality of contactless power supply devices, each of the plurality of wireless power supply devices is connected to an inverter that converts power supplied from a power source into AC power, and has a filter circuit including a reactor and a capacitor; an electrostatic coupling unit that electrostatically couples one of the non-contact power supply devices to another of the non-contact power supply devices, the electrostatic coupling unit having two capacitors electrically connected in parallel; a contactless power supply system including: an out-of-phase coil that is provided between the filter circuit of one of the contactless power supply devices and each of the two capacitors of the electrostatic coupling unit, and that has an inductance component when a short circuit or a ground fault occurs. [2] Each of the plurality of wireless power supply devices is a device that supplies a high-frequency current, The contactless power supply system according to [1], wherein the different-phase coil has the inductance component in the high-frequency current. [3] a plurality of power supply lines provided along a track rail on which the traveling vehicle travels; each of the plurality of wireless power supply devices wirelessly supplies power to the traveling vehicle traveling on the track rail; an area to which the AC power is supplied is set for each of the plurality of wireless power supply devices; The wireless power supply system according to [1] or [2], wherein each of the plurality of power supply lines is provided in a corresponding one of the areas. [4] The contactless power supply system according to any one of [1] to [3], further comprising a switching unit that switches between a coupled state and a non-coupled state of electrostatic coupling between one of the contactless power supply devices and another of the contactless power supply devices. [5] [1] to [4], and a contactless power supply system according to any one of [1] to [4]. a traveling vehicle that travels by receiving power transmitted from the wireless power supply system. [Explanation of symbols]

[0068] 1A, 1B, 1C, 1D, 1E... non-contact power supply device, 2... power supply, 8... inverter, 9... filter circuit, 12A, 12B... power supply line, 100... conveyance system, 110, 110A... non-contact power supply system, 112... electrostatic coupling unit, 114... out-of-phase coil, 120... ceiling transport vehicle (traveling vehicle), BR1... intra-beirut (area), BR2... inter-beirut (area), C0, C2... capacitor, C10, C20... capacitor, RT1, RT2... reactor, T... track rail.

Claims

1. A contactless power supply system including a plurality of contactless power supply devices, each of the plurality of wireless power supply devices is connected to an inverter that converts power supplied from a power source into AC power, and has a filter circuit including a reactor and a capacitor; an electrostatic coupling unit that electrostatically couples one of the non-contact power supply devices to another of the non-contact power supply devices, the electrostatic coupling unit having two capacitors electrically connected in parallel; a contactless power supply system including: an out-of-phase coil that is provided between the filter circuit of one of the contactless power supply devices and each of the two capacitors of the electrostatic coupling unit, and that has an inductance component when a short circuit or a ground fault occurs.

2. Each of the plurality of wireless power supply devices is a device that supplies a high-frequency current, The contactless power supply system according to claim 1 , wherein the different-phase coil has the inductance component in the high-frequency current.

3. a plurality of power supply lines provided along a track rail on which the traveling vehicle travels; each of the plurality of wireless power supply devices wirelessly supplies power to the traveling vehicle traveling on the track rail; an area to which the AC power is supplied is set for each of the plurality of wireless power supply devices; The contactless power supply system according to claim 1 , wherein each of the plurality of power supply lines is provided in a corresponding one of the areas.

4. The contactless power supply system according to claim 1 , further comprising a switching unit that switches between a coupled state and a non-coupled state of electrostatic coupling between one of the contactless power supply devices and another of the contactless power supply devices.

5. The contactless power supply system according to claim 1 or 2; a traveling vehicle that travels by receiving power transmitted from the wireless power supply system.

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