JP7375687B2 - Contactless power supply device - Google Patents

Description

The present disclosure relates to a contactless power supply device.

Conventionally, leakage electromagnetic fields were reduced by supplying alternating current to one power transmitting coil of adjacent power transmitting devices, and supplying alternating current with a phase difference of 180 degrees from the other power transmitting coil to the other power transmitting coil. A non-contact power supply device has been proposed (for example, see Patent Document 1).

JP 2016-5393 Publication

The present inventors have discovered that leakage occurs when alternating current with a phase difference of 180 degrees is supplied to adjacent power transmitting devices in a power transmitting device group in which four or more power transmitting devices are arranged in a row in a predetermined direction. We considered electromagnetic fields. According to this, it was found that the leakage electromagnetic field could not be reduced as expected on the end side of the power transmission device group, and there was still room for improvement.

An object of the present disclosure is to provide a non-contact power supply device that can suppress leakage electromagnetic fields on at least one end side of a group of power transmission devices.

The invention according to claim 1 includes:
A contactless power supply device that supplies power to moving vehicles (RT1 to RTm) in a contactless manner,
A plurality of power transmission devices (PTD) that transmit power contactlessly,
A power receiving device (PRD) that contactlessly receives power output from the power transmission device and supplies the received power to a power storage device (BT) of a moving vehicle,
The plurality of power transmission devices include a power transmission device group (PTU) in which four or more power transmission devices are arranged in a row in a predetermined direction,
The power transmission device includes a power transmission coil (20) having a coil portion (21A) around which a conductor is wound and a core portion (22A) that induces magnetic flux from the coil portion, and is capable of adjusting the phase of the current flowing through the power transmission coil. configured,
Among the power transmission device group, when the four power transmission devices located on one side in a predetermined direction are the first device (PTD1), the second device (PTD2), the third device (PTD3), and the fourth device (PTD4), The first device, the second device, the third device, and the fourth device are arranged such that the distance from one end of the power transmission device group in a predetermined direction increases in this order,
In the second device and the third device, the phase of the current is adjusted so that the direction of the magnetic field generated in each power transmission coil when energized is opposite to the direction of the magnetic field generated in the power transmission coil of the first device when energized,
In the fourth device, the phase of the current is adjusted so that the direction of the magnetic field generated in the power transmission coil of the fourth device when energized is the same as the direction of the magnetic field generated in the power transmission coil of the first device when energized.

According to this, in the power transmission device group, the leakage electromagnetic field generated in the power transmission coils of the second device and the third device, which are close to the first device, acts to cancel the leakage electromagnetic field generated in the first device. In this case, compared to the conventional case where the direction of the magnetic field generated in the power transmission coil of the third device is the same as the direction of the magnetic field generated in the power transmission coil of the first device, the leakage electromagnetic field generated in the first device can be sufficiently suppressed. can be reduced to

Further, since the direction of the magnetic field generated in the power transmission coil of the fourth device is opposite to the direction of the magnetic field generated in the power transmission coil of the second device and the third device, the power transmission coil of the second device and the third device It is possible to prevent the leakage electromagnetic field generated from becoming more excessive than necessary.

Therefore, according to the contactless power supply device of the present disclosure, it is possible to reduce the leakage electromagnetic field on at least one end side of the power transmission device group.

Note that the reference numerals in parentheses attached to each component etc. indicate an example of the correspondence between the component etc. and specific components etc. described in the embodiments to be described later.

FIG. 2 is a schematic top view showing an example of the arrangement in a factory of various components of a component assembly system to which a non-contact power supply device according to an embodiment is applied. FIG. 2 is a schematic diagram showing various constituent devices on the power transmission side and the power reception side of the non-contact power supply device according to the embodiment. FIG. 1 is a schematic overall configuration diagram of a non-contact power supply device according to an embodiment. FIG. 2 is an explanatory diagram for explaining a transmission line that connects control circuits in each power transmission device of the non-contact power supply device according to the embodiment. FIG. 2 is a schematic perspective view showing a state in which a power transmission pad and a power reception pad of a non-contact power supply device according to an embodiment are facing each other. FIG. 3 is a diagram of the power transmission pad of the non-contact power supply device according to the embodiment, viewed from the coil axis direction. FIG. 3 is a diagram of the power receiving pad of the non-contact power supply device according to the embodiment, viewed from the coil axis direction. FIG. 2 is a schematic perspective view showing an arrangement of adjacent power transmission devices of the non-contact power supply device according to the embodiment. FIG. 3 is an explanatory diagram for explaining how to flow current to each power transmission device of the non-contact power supply device according to the embodiment. FIG. 3 is a contour diagram of a leakage electromagnetic field on the XY plane when transmitting electric power by flowing a current corresponding to the first pattern to 20 power transmission devices. FIG. FIG. 7 is a contour diagram of a leakage electromagnetic field on the XY plane when power is transmitted by flowing current corresponding to the second pattern to four power transmission devices. FIG. 7 is a contour diagram of a leakage electromagnetic field on the XY plane when transmitting electric power by flowing a current corresponding to the second pattern to 20 power transmission devices. FIG. 7 is an explanatory diagram for explaining the effect of canceling a far-field leakage electromagnetic field when transmitting electric power by flowing a current corresponding to a second pattern to each power transmission device. FIG. 6 is an explanatory diagram for explaining the state of the switching elements of each inverter circuit when a current corresponding to a third pattern is passed through each power transmission device in the non-contact power supply device according to the embodiment. FIG. 7 is an explanatory diagram for explaining the effect of canceling a far-field leakage electromagnetic field when transmitting electric power by flowing a current corresponding to a third pattern to each power transmission device. FIG. 7 is a contour diagram of a leakage electromagnetic field on an XY plane when transmitting electric power by flowing a current corresponding to a third pattern to four power transmission devices. FIG. 7 is a contour diagram of a leakage electromagnetic field on the XY plane when transmitting electric power by flowing a current corresponding to the third pattern to 20 power transmission devices. FIG. 7 is an explanatory diagram for explaining the difference between the leakage electromagnetic field and the leakage electromagnetic field when power is supplied by flowing currents corresponding to the second pattern and the third pattern to four power transmission devices. FIG. 7 is an explanatory diagram for explaining the difference between the leakage electromagnetic field and the leakage electromagnetic field when power is supplied by flowing current corresponding to each pattern to 20 power transmission devices. FIG. 7 is an explanatory diagram for explaining a transmission line that connects control circuits in each power transmission device of a non-contact power supply device according to a modification. FIG. 7 is a contour diagram of a leakage electromagnetic field on the XY plane when transmitting electric power by flowing a current corresponding to the second pattern to six power transmission devices. FIG. 7 is a contour diagram of a leakage electromagnetic field on the XY plane when power is transmitted by flowing current corresponding to a pattern shown in a modified example to six power transmission devices. FIG. 7 is an explanatory diagram for explaining the difference between leakage electromagnetic fields when supplying electric power by flowing currents corresponding to the second pattern and the pattern shown in the modified example to six power transmission devices.

An embodiment of the present disclosure will be described based on FIGS. 1 to 19. In this embodiment, an example will be described in which the non-contact power supply device 1 of the present disclosure is applied to a component assembly system using mobile robots RT1 to RTm. In each drawing, the vertical direction, which is the direction of gravity, is the Z direction, one horizontal direction is the X direction, and the direction orthogonal to each of the Z direction and the X direction is the Y direction.

The parts assembly system is an automation system built within the factory. As shown in FIG. 1, the parts assembly system has two assembly lines AL1 and AL2 set in a factory. The parts assembly system performs the assembly work of parts P by m mobile robots RT1 to RTm arranged in two assembly lines AL1 and AL2, respectively.

The two assembly lines AL1 and AL2 have the same basic components. In this embodiment, the components of the two assembly lines AL1 and AL2 will be described with the same reference numerals.

On the assembly lines AL1 and AL2, n shelves SF, which are more than the mobile robots RT1 to RTm, are arranged in a line along the Y direction. In FIG. 1 and the like, a number, etc. when counted from one end side in the Y direction is added to "SF" of the shelves SF so that the shelves SF arranged in a row can be individually specified. For example, the shelf SF at one end in the Y direction is designated as "SF1", and the shelf SF at the other end in the Y direction is designated as "SFn".

A plurality of returnable boxes RB are arranged in line along the X direction on each of the plurality of shelves SF. The returnable box RB is a box for accommodating a plurality of types of parts P that constitute a certain product. The same type of parts P are stored in returnable boxes RB arranged on the same shelf SF (that is, returnable boxes RB lined up in the X direction). Further, different types of parts P are stored in returnable boxes RB stored in different shelves SF (that is, returnable boxes RB lined up in the Y direction).

As shown in FIG. 2, each of the plurality of shelves SF is provided with a transport device CD that slides the returnable box RB in the Y direction. This transport device CD allows returnable boxes RB to be exchanged between a plurality of shelves SF.

Each of the plurality of shelves SF is provided with a power transmission device PTD, which constitutes a part of the non-contact power supply device 1, on the moving path MR side of the mobile robots RT1 to RTm in the X direction. Specifically, the power transmission device PTD is attached to the side surface of each shelf SF on the moving path MR side. In the assembly lines AL1 and AL2 of this embodiment, n power transmission devices PTD are provided corresponding to each shelf SF. The plurality of power transmitting devices PTD includes a power transmitting device group PTU in which four or more power transmitting devices PTD are arranged in a row in a predetermined direction. In this embodiment, n power transmission devices PTD are arranged along the Y direction at predetermined intervals (for example, about 1 m). Therefore, the power transmission device group PTU is composed of n power transmission devices PTD arranged in a row along the Y direction. Note that the power transmitting device group PTU of this embodiment is configured of four power transmitting devices PTD or a multiple of four power transmitting devices PTD.

Here, in FIG. 1 and the like, a number counted from one end in the Y direction is added to "PTD" of the power transmitting devices PTD so that the power transmitting devices PTD arranged in a row can be individually identified. For example, the power transmission device PTD located at one end in the Y direction is designated as "PTD1", and the power transmission device PTD located at the other end in the Y direction is designated as "PTDn".

The power transmission device PTD is a device for contactlessly transmitting power. Power transmitting device PTD supplies power to power storage devices BT of mobile robots RT1 to RTm via power receiving devices PRD mounted on mobile robots RT1 to RTm. Details of the power transmission device PTD will be described later.

As shown in FIGS. 2 and 3, the power transmission device PTD is connected in parallel between the output electrodes of the AC/DC converter ADC. The AD/DC converter ADC is a voltage converter that converts the commercial frequency voltage of the system power supply SP into a DC voltage.

The system power source SP is an AC power source that receives power from a power system that is a power grid provided by a power company or the like. The system power supply SP outputs, for example, a three-phase AC voltage with an output voltage of 200 V and a frequency of 60 Hz. Note that the system power supply SP may be configured to output a single-phase AC voltage with an output voltage of 200 V and a frequency of 50 Hz.

Here, the movement paths MR of the mobile robots RT1 to RTm are set on the sides of each of the plurality of shelves SF and extend along the Y direction. The position where the power transmission device PTD is placed on the movement route MR is a charging spot for charging the power storage devices BT of the mobile robots RT1 to RTm.

The mobile robots RT1 to RTm move between multiple shelves SF to pick up necessary parts P from returnable boxes RB, and assemble the parts picked up while moving between multiple shelves SF. Implement. Mobile robots RT1 to RTm include a transport vehicle CV, a manipulator MP, a power storage device BT, a device control circuit CU, and a power receiving device PRD. In this embodiment, mobile robots RT1 to RTm correspond to the mobile vehicle of the present disclosure.

The transport vehicle CV has a base BS on which a manipulator MP and the like are installed, and wheels WL that are rotationally driven by an electric motor (not shown). The transport vehicle CV is movable in front of any shelf SF by rotationally driving the wheels WL based on a command from the equipment control circuit CU.

Manipulator MP includes dual-arm robot arms AM1 and AM2. The manipulator MP is capable of picking and assembling parts P based on commands from the equipment control circuit CU. The manipulator MP, for example, assembles a part P picked up from a returnable box RB with one robot arm AM1 onto another part P in cooperation with the other robot arm AM2.

Power storage device BT is a power source for electric loads EL such as wheels WL of transport vehicle CV and manipulator MP. Power storage device BT includes a lithium battery LB and an SOC detection circuit SC that detects the remaining amount of power stored in the lithium battery LB (SOC: State of Charge). Lithium battery LB is a nonaqueous secondary battery that can be charged and discharged. The lithium battery LB is capable of storing power transmitted from the power transmission device PTD.

The device control circuit CU includes a computer including a processor and a memory, peripheral circuits of the computer, and the like. The device control circuit CU executes various device control processes according to computer programs stored in advance in a memory. By executing this equipment control process, the electric loads EL such as the wheels WL of the transport vehicle CV and the manipulator MP are controlled.

The power receiving device PRD is a device that contactlessly receives power output from the power transmitting device PTD and supplies the received power to the power storage devices BT of the mobile robots RT1 to RTm. The power receiving device PRD constitutes the contactless power feeding device 1 together with the power transmitting device PTD.

Here, in FIG. 1, etc., in order to individually identify the power receiving devices PRD of the mobile robots RT1 to RTm, the power receiving devices are added with a number counted from one end in the Y direction to "PRD". This is the reference code for PRD. For example, the power receiving device PRD of the mobile robot RT1 located at one end in the Y direction is designated as "PRD1", and the power receiving device PRD of the mobile robot RTm located at the other end in the Y direction is designated as "PRDm".

Hereinafter, the overall configuration of the non-contact power supply device 1 will be described with reference to FIG. 3. As shown in FIGS. 2 and 3, the contactless power supply device 1 includes n (n≧4) power transmitting devices PTD and m (4≦m<n) power receiving devices PRD. The contactless power supply device 1 is configured such that when the mobile robots RT1 to RTm are aligned so that the power transmitting device PTD and the power receiving device PRD face each other in the X direction, power is supplied from the power transmitting device PTD to the power receiving device PRD. It is composed of

Each of the power transmitting devices PTD includes a power transmitting coil 20, an inverter circuit 21, a communication circuit 22 that communicates with the power receiving device PRD side, a control circuit 23, a light receiving element 24, and the like.

The inverter circuit 21 outputs alternating current to the power transmission coil 20. The inverter circuit 21 includes a first switching element 211, a second switching element 212, a third switching element 213, a fourth switching element 214, and a smoothing capacitor 215. Inverter circuit 21 is controlled by control circuit 23 .

The smoothing capacitor 215 is for smoothing the output voltage of the AC/DC converter ADC. Smoothing capacitor 215 is connected between the output electrodes of AC/DC converter ADC.

The first switching element 211 and the second switching element 212 are connected in series between the output electrodes of the AC/DC converter ADC. The third switching element 213 and the fourth switching element 214 are connected in series between the output electrodes of the AC/DC converter ADC. The series connection body of the first switching element 211 and the second switching element 212 and the series connection body of the third switching element 213 and the fourth switching element 214 are electrically connected in parallel.

For each of the switching elements 211, 212, 213, and 214, various semiconductor elements such as an insulated gate bipolar transistor, a field effect transistor, and a bipolar transistor are used.

A connecting portion T1 between the first switching element 211 and the second switching element 212, and a connecting portion T2 between the third switching element 213 and the fourth switching element 214 constitute an output electrode of the AC voltage in the inverter circuit 21. The inverter circuit 21 outputs an alternating current voltage from the connections T1 and T2 based on the output voltage of the AC/DC converter ADC by switching the respective switching elements 211, 212, 213, and 214. As a control method for the inverter circuit 21, for example, phase shift type PWM control is used.

The power transmission coil 20 transmits power by electromagnetic induction based on the alternating current flowing through the inverter circuit 21 . The power transmission coils 20 are connected to each other in series. The power transmission coil 20 is connected between the connection portions T1 and T2 of the inverter circuit 21. Details of the power transmission coil 20 will be described later.

The control circuit 23 is constituted by a computer including a processor and memory, peripheral circuits of the computer, and the like. The control circuit 23 executes various control processes according to computer programs stored in memory in advance. The inverter circuit 21 and the like are controlled by executing this control process.

The light receiving element 24, together with the light emitting element 37 provided in the power receiving device PRD, constitutes a distance sensor DS that measures the distance between the power transmitting device PTD and the power receiving device PRD. The light receiving element 24 outputs a detection signal indicating the intensity of light (for example, infrared rays) emitted by the light emitting element 37.

Here, each of the power transmitting devices PTD1 to PTDm is connected in a master-slave transmission format so that some of the power transmitting devices PTD1 to PTDm serve as master devices and others serve as slave devices. That is, in each power transmission device PTD1 to PTDm, each control circuit 23 is connected in a master-slave type transmission configuration so that each inverter circuit 21 can be driven synchronously. In each of the power transmission devices PTD1 to PTDm, the control circuit 23 of the power transmission device PTD1 located on one side in the Y direction constitutes a driver DV of the differential line L which is a transmission line, and the control circuit 23 of the other power transmission devices PTD2 to PTDm constitutes the receiver RV of the differential line L.

FIG. 4 shows each power transmitting device PTD1 to PTD4 when a power transmitting device group PTU is configured by four power transmitting devices PTD1, second power transmitting device PTD2, third power transmitting device PTD3, and fourth power transmitting device PTD4 arranged in a row. The transmission format is shown below.

As shown in FIG. 4, each of the power transmission devices PTD1 to PTD4 constitutes a driver DP of a differential line L in which a part of the control circuit 23 of the first power transmission device PTD1 located on one side in the Y direction is a transmission line. . Moreover, a part of the control circuit 23 of the second power transmission device PTD2, the third power transmission device PTD3, and the fourth power transmission device PTD4 constitutes the receiver RV of the differential line L. A terminating resistor ER having a resistance value of about 100Ω is arranged at the end of the differential line L, which is a transmission line.

The control circuit 23 of the first power transmission device PTD1, which is a master device, outputs a synchronization signal and operation signals for each of the switching elements 211 to 214 to the second power transmission device PTD2, the third power transmission device PTD3, and the fourth power transmission device PTD4. .

On the other hand, the power receiving device PRD includes a power receiving coil 30, a rectifier circuit 31, a choke coil 32, a smoothing capacitor 33, a current sensor 34, a voltage sensor 35, a communication circuit 36 communicating with the power transmitting device PTD, a light emitting element 37, a control circuit 38, etc. Equipped with

The power receiving coil 30 receives power from the power transmitting coil 20 by electromagnetic induction. Power receiving coils 30 are connected to each other in series. The power receiving coil 30 is arranged at a predetermined interval so as to be able to face the power transmitting coil 20. Details of the power receiving coil 30 will be described later.

The rectifier circuit 31 rectifies the AC voltage output from the power receiving coil 30 and outputs the rectified voltage from the output electrodes 315 and 316. The rectifier circuit 31 includes a bridge circuit including a first diode 311, a second diode 312, a third diode 313, and a fourth diode 314. The first diode 311 and the fourth diode 314 are connected in series between the output electrodes P1 and P2 of the power receiving coil 30. The second diode 312 and the third diode 313 are connected in series between the output electrodes P1 and P2 of the power receiving coil 30. The series connection body of the first diode 311 and the fourth diode 314 and the series connection body of the second diode 312 and the third diode 313 are electrically connected in parallel.

Here, the output electrode P1 of the power receiving coil 30 is a connection portion between the anode electrode of the first diode 311 and the cathode electrode of the second diode 312. Further, the output electrode P2 of the power receiving coil 30 is a connection portion between the cathode electrode of the third diode 313 and the anode electrode of the fourth diode 314.

The choke coil 32 and the smoothing capacitor 33 constitute a filter circuit that suppresses pulsations in the output power of the rectifier circuit 31. The choke coil 32 is connected in series between the output electrode 315 of the rectifier circuit 31 and the positive electrode of the smoothing capacitor 33. Smoothing capacitor 33 is connected between output electrodes 315 and 316 of rectifier circuit 31 .

The output electrode 315 of the rectifier circuit 31 is a connection portion between the cathode electrodes of the first diode 311 and the fourth diode 314. Further, the output electrode 316 of the rectifier circuit 31 is a connection portion between the anode electrodes of the second diode 312 and the third diode 313.

Current sensor 34 and voltage sensor 35 are provided between power storage device BT and rectifier circuit 31. Current sensor 34 detects the current flowing from the negative terminal of power storage device BT to output electrode 316 of rectifier circuit 31. Voltage sensor 35 detects the voltage between both terminals of power storage device BT.

The light emitting element 37 and the light receiving element 24 constitute a distance sensor DS. The light emitting element 37 is composed of a light emitting diode that emits light (for example, infrared light). The operation of the light emitting element 37 is controlled by a control circuit 38.

The control circuit 38 is constituted by a computer including a processor and memory, peripheral circuits of the computer, and the like. The control circuit 38 executes various control processes according to computer programs stored in memory in advance.

The control circuit 38 cooperates with the control circuit 23 on the power transmission device PTD side to execute charging control processing for charging the power storage device BT. For example, in the charging control process, when the SOC of power storage device BT becomes equal to or less than a predetermined value, control circuit 38 transmits a power supply signal requesting power supply to power storage device BT via communication circuit 36 to power transmission device 3 side. In the charging control process, the inverter circuit 21 is controlled based on, for example, the power supply signal received by the power transmission device 3 through the communication circuit 22, the intensity of light detected by the light receiving element 24, and the like.

Next, FIGS. 5 to 7 will be referred to for details of the power transmitting coil 20 and the power receiving coil 30 of this embodiment.

As shown in FIGS. 5 and 6, the power transmission coil 20 constitutes the power transmission pad TP, and is covered with a cover C that shields magnetic flux. This cover C has a size that can cover both of the power transmission coils 20. The cover C is made of a metal material such as aluminum.

The power transmission coil 20 is arranged with the coil axis extending along the X direction. Note that the coil axis is the central axis of the winding of the power transmission coil 20. The power transmission coil 20 has a coil portion 21A in which a conductor is wound and a core portion 22A that induces magnetic flux generated in the coil portion 21A when energized.

The coil portion 21A is a winding in which a litz wire, which is a conductor, is wound around a bobbin (not shown). The coil portion 21A of this embodiment has a winding number of about 10 turns.

Each of the core portions 22A is composed of a ferrite core made of ferrite, which is a magnetic material. The core portion 22A has a shape that covers a part of the coil portion 21A. The core portion 22A of this embodiment has a cross-sectional shape of the letter "E".

Specifically, the core portion 22A includes a main surface portion 221 that faces the coil portion 21A in the coil axial direction, and a pair of main surface portions 221 that are continuous with the main surface portion 221 and that face the outermost circumferential surface of the coil portion 21A in a direction orthogonal to the coil axial direction. It has side parts 222 and 223. Specifically, the core portion 22A is constituted by an E-shaped core having a center pole 224 that supports the coil portion 21A.

The main surface portion 221 is formed into a plate shape that extends in the XZ plane. A pair of side portions 222 and 223 are erected on main surface portion 221 so as to face each other via coil portion 21A. Specifically, the pair of side surfaces 222 and 223 protrude from both ends of the main surface section 221 in the Z direction toward one side in the X direction. The center pole 224 holds the center portion of the coil portion 21A (the center portion of the bobbin, not shown). The center pole 224 is arranged between the pair of side parts 222 and 223, and protrudes from the central part of the main surface part 221 in the Z direction toward one side in the X direction.

As shown in FIGS. 5 and 7, the power receiving coil 30 constitutes the power receiving pad RP and is covered with a cover C that shields magnetic flux. This cover C has a size that can cover both of the power receiving coils 30. The cover C is made of a metal material such as aluminum.

The power receiving coil 30 has basically the same structure as the power transmitting coil 20. Therefore, the explanation regarding each component in the power receiving coil 30 will be simplified.

The power receiving coil 30 is arranged with the coil axis extending along the X direction. The power receiving coil 30 has a coil portion 31A in which a conductor is wound and a core portion 32A that induces magnetic flux generated in the coil portion 31A when energized.

The coil portion 31A of the power receiving coil 30 has a smaller number of turns (for example, one turn) than the coil portion 21A of the power transmitting coil 20. This allows the power receiving device PRD to handle large currents.

The core portion 32A of the power receiving coil 30 is arranged to be line symmetrical with the core portion 22A of the power transmitting coil 20, and forms a magnetic path (that is, a magnetic path) together with the core portion 22A of the power transmitting coil 20. Specifically, the core portion 32A is composed of an E-shaped core having a main surface portion 321 facing the coil portion 31A, a pair of side surfaces 322 and 323 continuous to the main surface portion 321, and a center pole 324 that supports the coil portion 31A. has been done.

Here, as shown in FIG. 8, adjacent power transmission devices PTD are arranged at a predetermined interval (for example, about 1 m) in the Y direction. Adjacent power transmission devices PTD are arranged so that the side surfaces 322 and 323 are lined up in a line so that the side surfaces 322 and 323 are not interposed between the coil portions 31A. Adjacent power transmission devices PTD are arranged such that their respective side surfaces 222 and 223 are lined up in a row along the Y direction.

In the contactless power feeding device 1 configured as described above, when power is supplied from the power transmitting device PTD to the power receiving device PRD, the power transmitting coil 20 and the power receiving coil 30 are positioned at positions facing each other. supply current to. Specifically, when power is supplied from the power transmitting device PTD to the power receiving device PRD, the power transmitting coil 20 and the power receiving coil 30 are positioned to face each other with a predetermined gap in the X direction. Thereby, the power transmitting coil 20 and the power receiving coil 30 are transformer-coupled in a non-contact state, and electromagnetic induction is efficiently performed.

Next, an outline of the operation of the parts assembly system will be explained. In the parts assembly system, when the wheels WL of the transport vehicle CV are driven by the equipment control circuit CU, the mobile robots RT1 to RTm move on the movement path ML.

The mobile robots RT1 to RTm stop in front of a returnable box RB on a predetermined shelf SF, and pick up a desired part P from the returnable box RB using a manipulator MP. When a part P is picked up by the manipulator MP, the mobile robots RT1 to RTm perform assembly work on the part P and move in front of the returnable box RB in which the parts P to be assembled next are stacked in bulk. Then, it stops in front of the returnable box RB and picks up the part P to be assembled next.

In this manner, in the parts assembly system, the picking and assembly operations of parts P are automatically repeated by the mobile robots RT1 to RTm.

The non-contact power supply device 1 determines whether it is stopped in front of the returnable box RB based on the intensity of light received by the light receiving element 24. Then, when the mobile robots RT1 to RTm are stopped in front of the returnable box RB, power is supplied from the power transmission device PTD provided on each shelf SF to the power receiving device PRD of the mobile robots RT1 to RTm. That is, the contactless power supply device 1 supplies power from the power transmission device PTD to the power reception device PRD while the manipulator MP is picking up the component P. Power receiving device PRD rectifies the received power from power transmitting device PTD using rectifier circuit 31, and then charges power storage device BT.

As described above, the non-contact power supply device 1 charges the power storage devices BT of the mobile robots RT1 to RTm when picking a part P. According to the non-contact power supply device 1, compared to the conventional system in which the power supply area of the mobile robots RT1 to RTm is set in an area different from the area where the shelves SF are arranged, a decrease in the operating rate due to power supply is suppressed, The surplus of high-cost mobile robots RT1 to RTm can be reduced. That is, by applying the non-contact power supply device 1 to the mobile robots RT1 to RTm, it is possible to reduce the number of redundant robots and reduce the equipment installation cost.

However, for example, if the power transmitting devices PTD are simply installed with an interval of about 1 m, the leakage electromagnetic fields generated at the power transmitting pad TP and the power receiving pad RP will be combined when charging multiple mobile robots RT1 to RTm at the same time. The leakage electromagnetic field generated at a distance exceeds the regulation value.

Here, in the conventional non-contact power transfer device 1, for example, as shown in the first pattern in FIG. , a plurality of mobile robots RT1 to RTm may be charged at the same time. In this case, leakage electromagnetic fields generated in each power transmitting device PTD and power receiving device PRD are combined.

FIG. 10 shows the magnetic flux distribution on the XY plane when 20 mobile robots RT1 to RTm are charged by flowing a first pattern of current (current with the same phase) through the power transmission coil 20 of each power transmission device PTD. FIG. Note that FIG. 10 shows a state where the gap between the power transmission pad TP and the power reception pad RP is 4 mm, and the power transmission pad TP and the power reception pad RP are deviated from the proper position by 10 mm in the Y direction and the Z direction (Gap=4 mm, ΔY=10 mm, ΔZ= 10 mm).

As shown in FIG. 10, when currents of the same phase are passed through the power transmitting coils 20 of each power transmitting device PTD, leakage electromagnetic fields generated in each power transmitting device PTD and power receiving device PRD are combined. As a result, the leakage electromagnetic field generated at the far position XP exceeds the regulation value Va.

On the other hand, for example, as in the second pattern shown in FIG. 9, alternating currents (currents with opposite phases) having a phase difference of 180 degrees are passed through the power transmitting coils 20 of adjacent power transmitting devices PTD1 to PTDm, and multiple It is conceivable to charge the mobile robots RT1 to RTm at the same time. In this case, leakage electromagnetic fields generated in the adjacent power transmitting device PTD and power receiving device PRD act to cancel each other out.

FIG. 11 shows the magnetic flux distribution on the XY plane when four mobile robots RT1 to RTm are charged by flowing a second pattern of current (current with opposite phase) to the power transmission coil 20 of the adjacent power transmission device PTD. FIG. Furthermore, FIG. 12 is a contour diagram showing the magnetic flux distribution on the XY plane when 20 mobile robots RT1 to RT20 are charged by flowing a second pattern of current to the power transmission coil 20 of the adjacent power transmission device PTD. It is. Note that FIGS. 11 and 12 show a state where the gap between the power transmission pad TP and the power reception pad RP is 4 mm, and the power transmission pad TP and the power reception pad RP are deviated from the proper position by 10 mm in the Y direction and the Z direction (Gap = 4 mm, ΔY = 10 mm). , ΔZ=10 mm).

As shown in FIGS. 11 and 12, when currents with opposite phases flow through the power transmission coils 20 of adjacent power transmission devices PTD, leakage electromagnetic fields generated in the adjacent power transmission devices PTD and power reception devices PRD act to cancel each other out. . As a result, the leakage electromagnetic field generated at the far position XP becomes smaller than the regulation value Va.

However, according to the studies of the present inventors, when charging the mobile robots RT1 to RTm by flowing currents of opposite phases to the power transmission coils 20 of adjacent power transmission devices PTD, the power transmission It has been found that the leakage electromagnetic field becomes noticeable on the end side of the device group PTU. That is, when the mobile robots RT1 to RTm are charged by flowing a second pattern of current (current with opposite phase) to the power transmission coil 20 of the adjacent power transmission device PTD, a leakage electromagnetic field is generated at the end side of the power transmission device group PTU. I can't reduce it as much as I expected.

Here, as shown in FIGS. 13 and 15, it is assumed that the power transmitting device PTD and the power receiving device PRD that constitute the power transmitting device group PTU are minute current elements Idy adjacent to each other in the Y direction. Further, regarding the power transmitting devices PTD constituting the power transmitting device group PTU, those located on one side in the Y direction are referred to as a first power transmitting device PTD1, a second power transmitting device PTD2, a third power transmitting device PTD3, and a fourth power transmitting device PTD4. . The first power transmitting device PTD1, the second power transmitting device PTD2, the third power transmitting device PTD3, and the fourth power transmitting device PTD4 are arranged such that the distance from one end of the power transmitting device group PTU in the Y direction increases in this order. Placed. Note that in the present embodiment, the first power transmitting device PTD1, the second power transmitting device PTD2, the third power transmitting device PTD3, and the fourth power transmitting device PTD4 are the first power transmitting device, the second device, the third device, and the third power transmitting device of the present disclosure. Compatible with 4 devices.

When charging mobile robots RT1 to RTm by flowing currents with opposite phases to four adjacent power transmitting devices PTD, leakage occurs at a distant position XP that is R [m] away from the first power transmitting device PTD1 at the end in the Y direction. The electromagnetic field ΔH is expressed by the formula F1 shown in FIG. 13 according to the Biot-Savart law. Note that α shown in FIG. 13 is the interval between adjacent power transmission devices PTD in the Y direction. Further, θ1, θ2, and θ3 shown in FIG. 13 are the second imaginary line IL1 that is parallel to the Y direction, and the second imaginary line that connects the far position XP, the second power transmitting device PTD2, the third power transmitting device PTD3, and the fourth power transmitting device PTD4. ~ This is the angle formed by the fourth virtual lines IL2 to IL4.

According to formula F1 shown in FIG. 13, the leakage electromagnetic field generated in the first power transmission device PTD1 acts to cancel out the leakage electromagnetic field generated in the adjacent second power transmission device PTD2. On the other hand, it acts so that the leakage electromagnetic fields generated in the third power transmitting device PTD3 adjacent to the second power transmitting device PTD2 are combined. Therefore, when charging the four mobile robots RT1 to RTm by flowing a second pattern of current (current with opposite phase) to the adjacent power transmission device PTD, the leakage electromagnetic field is generated at the end of the power transmission device group PTU. I can't reduce it as much as I expected.

Taking these into account, in this embodiment, as shown in the third pattern in FIG. And currents of opposite phases are passed through the power transmission coil 20 of the third power transmission device PTD3. That is, in the non-contact power supply device 1, the second power transmission device PTD2 and the third power transmission device PTD3 have the direction of the magnetic field generated in each power transmission coil 20 when energized is the same as the magnetic field generated in the power transmission coil 20 of the first power transmission device PTD1 when energized. The phase of the current is adjusted so that it is in the opposite direction. The fourth power transmitting device PTD4 also controls the current flow so that the direction of the magnetic field generated in the power transmitting coil 20 of the fourth power transmitting device PTD4 when energized is the same as the direction of the magnetic field generated in the power transmitting coil 20 of the first power transmitting device PTD1 when energized. The phase of is adjusted. Specifically, as shown in FIG. 14, the contactless power transfer device 1 connects the power transmitting coils 20 of the second power transmitting device PTD2 and the third power transmitting device PTD3 to the power transmitting coils 20 of the first power transmitting device PTD1 and the fourth power transmitting device PTD4. An alternating current having a phase difference of 180 degrees with the alternating current flowing through the power transmission coil 20 is passed.

When charging the mobile robots RT1 to RTm using such a power supply mode, the leakage electromagnetic field ΔH at a far position XP that is R [m] away from the first power transmission device PTD1 located at the end in the Y direction is According to Savard's law, it is expressed by formula F2 shown in FIG. 15.

According to formula F2 shown in FIG. 15, the leakage electromagnetic field generated in the second power transmission device PTD2 and the third power transmission device PTD3 acts to cancel the leakage electromagnetic field generated in the first power transmission device PTD1. Therefore, the leakage electromagnetic field generated in the first power transmitting device PTD1 can be sufficiently reduced compared to the case where the second pattern of current (current with opposite phase) flows through the adjacent power transmitting devices PTD.

Further, the leakage electromagnetic field generated in the fourth power transmission device PTD4 acts to cancel the leakage electromagnetic field generated in the second power transmission device PTD2 and the third power transmission device PTD3. Therefore, it is possible to prevent the leakage electromagnetic field generated in the second power transmission device PTD2 and the third power transmission device PTD3 from becoming more excessive than necessary.

FIG. 16 shows the magnetic flux distribution on the XY plane when four mobile robots RT1 to RTm are charged by flowing a third pattern of current through the power transmission coil 20 of the power transmission device PTD that constitutes the power transmission device group PTU. FIG. Further, FIG. 17 shows the magnetic flux on the XY plane when 20 mobile robots RT1 to RT20 are charged by flowing a third pattern of current through the power transmission coil 20 of the power transmission device PTD that constitutes the power transmission device group PTU. It is a contour diagram showing distribution. Note that FIGS. 16 and 17 show a state in which the gap between the power transmission pad TP and the power reception pad RP is 4 mm, and the power transmission pad TP and the power reception pad RP are deviated from the proper position by 10 mm in the Y direction and the Z direction (Gap = 4 mm, ΔY = 10 mm). , ΔZ=10 mm).

As shown in FIGS. 16 and 17, when the third pattern of current is passed through the power transmission coil 20 of the power transmission device PTD that constitutes the power transmission device group PTU, the power transmission device group PTU The leakage electromagnetic field can be reduced on the end side. Specifically, as shown in FIGS. 18 and 19, the maximum value of the leakage electromagnetic field generated at the far position XP is significantly smaller than when the second pattern of current is passed.

The non-contact power supply device 1 described above allows currents of the same phase to flow through the power transmission coils 20 of the first power transmission device PTD1 and the fourth power transmission device PTD4 on one side in the Y direction of the power transmission device group PTU, and A current with an opposite phase is passed through the power transmission coil 20 of the third power transmission device PTD3.

According to this, in the power transmission device group PTU, the leakage electromagnetic field generated in the power transmission coils 20 of the second power transmission device PTD2 and the third power transmission device PTD3, which are close to the first power transmission device PTD1, suppresses the leakage electromagnetic field generated in the first power transmission device PTD1. It acts to cancel it out. In this case, the first power transmitting device The leakage electromagnetic field generated in the PTD 1 can be sufficiently reduced.

Further, the direction of the magnetic field generated in the power transmission coil 20 of the fourth power transmission device PTD4 is opposite to the direction of the magnetic field generated in the power transmission coil 20 of the second power transmission device PTD2 and the third power transmission device PTD3. Therefore, it is possible to suppress the leakage electromagnetic field generated in the power transmission coils 20 of the second power transmission device PTD2 and the third power transmission device PTD3 from becoming more excessive than necessary.

As described above, according to the contactless power supply device 1 of the present embodiment, it is possible to reduce the leakage electromagnetic field at at least one end of the power transmission device group PTU. As a result, the degree of freedom in setting the power supply area of the mobile robots RT1 to RTm increases, and the power supply area can be increased, so that it is possible to suppress a decrease in the operating rate due to power supply. That is, by applying the non-contact power supply device 1 to the mobile robots RT1 to RTm, it is possible to reduce the number of redundant robots and reduce the equipment installation cost.

By the way, when there are five or more power transmitting devices PTD constituting the power transmitting device group PTU, the fifth device, the sixth device, the seventh device, This is the eighth device. Note that the fifth device, the sixth device, the seventh device, and the eighth device are arranged such that the distance from the other end of the power transmission device group PTU in the Y direction increases in this order.

When there are five or more power transmitting devices PTD constituting a power transmitting device group PTU, currents of the same phase are passed through the power transmitting coils 20 of the fifth device and the eighth device, and currents of opposite phase are passed through the power transmitting coils 20 of the sixth device and the seventh device. Flow an electric current. That is, in the non-contact power supply device 1, the direction of the magnetic field generated in each of the power transmission coils 20 of the sixth device and the seventh device when energized is opposite to the direction of the magnetic field generated in the power transmission coil 20 of the fifth device when energized. The phase of the current is adjusted so that Further, in the eighth device, the phase of the current is adjusted so that the direction of the magnetic field generated in the power transmission coil 20 of the eighth device when energized is the same as the direction of the magnetic field generated in the power transmission coil 20 of the fifth device when energized. . Thereby, the leakage electromagnetic field can be reduced not only at one end in the Y direction but also at the other end. That is, the leakage electromagnetic field at both ends of the power transmission device group PTU can be reduced.

Further, in the power transmission device group PTU, each device is connected in a master-slave transmission format such that some power transmission devices PTD serve as master devices and other power transmission devices PTD serve as slave devices. In this way, by connecting each device that makes up the power transmission device group PTU in a master-slave transmission mode, it is possible to easily adjust the phase of the current flowing through the power transmission coil 20 of each device that makes up the power transmission device group PTU. It can be realized.

(Modified example)
As long as the power transmitting device group PTU is composed of four or more power transmitting devices PTD, it may be composed of a number of power transmitting devices PTD other than four or a multiple of four.

For example, as shown in FIG. 20, the power transmission device group PTU may include six power transmission devices PTD. In this configuration, currents of the same phase are passed through the power transmitting coils 20 of the first power transmitting device PTD1 from one end side of the power transmitting device group PTU and the power transmitting coil 20 of the fourth power transmitting device PTD4 from the one end side, and Currents with opposite phases are passed through the power transmission coils 20 of the third power transmission devices PTD2 and PTD3. In addition, currents of the same phase are passed through the power transmitting coils 20 of the first power transmitting device PTD6 from the other end side of the power transmitting device group PTU and the power transmitting coil 20 of the fourth power transmitting device PTD3 from the other end side. Currents with opposite phases are passed through the power transmission coils 20 of the third power transmission devices PTD5 and PTD4. With this configuration, the same effects as those described in the above embodiment can be obtained.

Here, FIG. 21 is a contour diagram showing the magnetic flux distribution on the XY plane when six mobile robots RT1 to RTm are charged by flowing currents of opposite phases to the power transmission coils 20 of adjacent power transmission devices PTD. It is. Further, FIG. 22 shows an XY plane when six mobile robots RT1 to RTm are charged by applying current to the power transmission coil 20 of the power transmission device PTD constituting the power transmission device group PTU in the mode of this modification. FIG. 3 is a contour diagram showing the magnetic flux distribution of FIG. Note that FIGS. 21 and 22 show a state in which the gap between the power transmission pad TP and the power reception pad RP is 4 mm, and the power transmission pad TP and the power reception pad RP are deviated from the proper position by 10 mm in the Y direction and the Z direction (Gap = 4 mm, ΔY = 10 mm). , ΔZ=10 mm).

As shown in FIGS. 21 and 22, when a current is caused to flow in the power transmission coil 20 of a power transmission device PTD constituting a power transmission device group PTU in the mode of this modification, when a current with an opposite phase is caused to flow through an adjacent power transmission device PTD, In comparison, the leakage electromagnetic field can be reduced on the end side of the power transmission device group PTU. Specifically, the maximum value of the leakage electromagnetic field generated at the far position XP is significantly smaller than Va, which indicates the regulation value, as shown in FIG.

(Other embodiments)
Although typical embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and can be modified in various ways, for example, as described below.

In the above-described embodiment, an example was described in which the contactless power supply device 1 of the present disclosure is applied to a system having two rows of assembly lines AL1 and AL2. It is also applicable to a system having the above assembly line.

In the above-described embodiment, four or more power transmission devices PTD are arranged in a line along the Y direction at predetermined intervals, but the contactless power supply device 1 is not limited to this, and for example, Some of the plurality of power transmission devices PTD do not need to be lined up in a line along the Y direction. Note that the power transmission device group PTU may be configured by, for example, power transmission devices PTD lined up in a row along the X direction.

In the above-described embodiment, in consideration of the balance of the leakage electromagnetic field in the entire power transmitting device group PTU, it is desirable that the power transmitting device group PTU is configured with an even number of power transmitting devices PTD, but the present invention is not limited to this. The number of power transmitting devices PTD constituting the power transmitting device group PTU is not limited to an even number, but may be an odd number.

Here, it is preferable that the non-contact power supply device 1 is configured to reduce the leakage electromagnetic field at both ends of the power transmission device group PTU, as in the above-described embodiment, but the present invention is not limited to this. The non-contact power supply device 1 may be configured to reduce leakage electromagnetic fields at one end and the other end of the power transmission device group PTU, for example. In addition, regarding the power transmission device PTD located in the center among the power transmission device group PTU, currents having opposite phases may be supplied to adjacent power transmission devices PTD as in the conventional case.

In the above-described embodiment, a plurality of power transmitting devices PTD constituting the power transmitting device group PTU are connected in a master-slave transmission mode, but the power transmitting device group PTU is not limited to this. The power transmitting device group PTU may be connected in a transmission form other than the master-slave method if the phase of the current flowing through the power transmitting coil 20 of each of the plurality of power transmitting devices PTD constituting the power transmitting device group PTU can be adjusted appropriately. Good too.

In the above-described embodiment, the core portion 22A of the power transmission coil 20 is configured with an E-shaped core, but the core portion 22A is not limited to this, and may be configured with a core having another shape, for example. You can leave it there.

In the above embodiment, an example was described in which the non-contact power supply device 1 of the present disclosure is applied to a component assembly system using mobile robots RT1 to RTm, but the application of the non-contact power supply device 1 is limited to this. Not done. The non-contact power supply device 1 is applicable to a system using a mobile vehicle (for example, an automatic guided vehicle AGV) other than a parts assembly system. Further, the contactless power supply device 1 may be installed at a location other than a factory.

In the embodiments described above, it goes without saying that the elements constituting the embodiments are not necessarily essential, except in cases where it is specifically specified that they are essential, or where they are clearly considered essential in principle.

In the embodiments described above, when numerical values such as the number, numerical value, amount, range, etc. of the constituent elements of the embodiment are mentioned, it is especially specified that it is essential, or it is clearly limited to a specific number in principle. It is not limited to that specific number, except in certain cases.

In the above-described embodiments, when referring to the shape, positional relationship, etc. of components, etc., we refer to the shape, positional relationship, etc., unless explicitly stated or in principle limited to a specific shape, positional relationship, etc. etc., but not limited to.

The above-described embodiments should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is indicated by the claims rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

(summary)
According to the first aspect described in part or all of the above embodiments, the contactless power supply device includes a power transmission device group in which four or more power transmission devices are arranged in a row in a predetermined direction. . The power transmission device group includes four power transmission devices located on one side in a predetermined direction, including a first device, a second device, a third device, and a fourth device. The fourth devices are arranged in this order such that the distance from the one end in the predetermined direction increases. The phase of the current in the second device and the third device is adjusted so that the direction of the magnetic field generated in each power transmission coil when energized is opposite to the direction of the magnetic field generated in the power transmission coil of the first device when energized. . In the fourth device, the phase of the current is adjusted so that the direction of the magnetic field generated in the power transmission coil of the fourth device when energized is the same as the direction of the magnetic field generated in the power transmission coil of the first device when energized.

According to the second aspect, in the power transmission device group, five or more power transmission devices are arranged in a row in a predetermined direction. Among the power transmission device group, when the four power transmission devices located on the other side in the predetermined direction are the fifth device, the sixth device, the seventh device, and the eighth device, the fifth device, the sixth device, the seventh device, The eighth devices are arranged such that the distance from the other end in the predetermined direction of the power transmission device group increases in this order. In the sixth device and the seventh device, the phase of the current is adjusted so that the direction of the magnetic field generated in each power transmission coil when energized is opposite to the direction of the magnetic field generated in the power transmission coil of the fifth device when energized. . In the eighth device, the phase of the current is adjusted so that the direction of the magnetic field generated in the power transmission coil of the eighth device when energized is the same as the direction of the magnetic field generated in the power transmission coil of the fifth device when energized. According to this, it is possible to reduce the leakage electromagnetic field at both ends of the power transmission device group.

According to the third viewpoint, in the power transmission device group, each device is connected in a master-slave transmission format such that some power transmission devices act as master devices and other power transmission devices act as slave devices. . In this way, by connecting each device that makes up the power transmission device group in a master-slave transmission mode, it is possible to easily adjust the phase of the current flowing through the power transmission coil of each device that makes up the power transmission device group. Can be done.

1 Non-contact power supply device 2 Power transmission device 20 Power transmission coil 21A Coil part 22A Core part RT Mobile robot (mobile vehicle)
PTD Power transmission equipment PTU Power transmission equipment group

Claims (3)

A contactless power supply device that supplies power to moving vehicles (RT1 to RTm) in a contactless manner,
A plurality of power transmission devices (PTD) that transmit power contactlessly,
A power receiving device (PRD) that receives power output from the power transmission device in a contactless manner and supplies the received power to a power storage device (BT) of the mobile vehicle,
The plurality of power transmission devices include a power transmission device group (PTU) in which four or more of the power transmission devices are arranged in a line in a predetermined direction,
The power transmission device includes a power transmission coil (20) having a coil portion (21A) around which a conductor is wound and a core portion (22A) that induces magnetic flux from the coil portion, and adjusts the phase of the current flowing through the power transmission coil. configured to be adjustable;
Among the power transmission device group, the four power transmission devices located on one side in the predetermined direction are referred to as a first device (PTD1), a second device (PTD2), a third device (PTD3), and a fourth device (PTD4). In this case, the first device, the second device, the third device, and the fourth device are arranged such that the distance from one end of the power transmission device group in the predetermined direction increases in this order. ,
The second device and the third device transmit current so that the direction of the magnetic field generated in each of the power transmission coils when energized is opposite to the direction of the magnetic field generated in the power transmission coil of the first device when energized. The phase is adjusted,
In the fourth device, the phase of the current is adjusted such that the direction of the magnetic field generated in the power transmission coil of the fourth device when energized is the same as the direction of the magnetic field generated in the power transmission coil of the first device when energized. A wireless power transfer device. The power transmission device group includes five or more power transmission devices arranged in a row in the predetermined direction,
Among the power transmission device group, when the four power transmission devices located on the other side in the predetermined direction are a fifth device, a sixth device, a seventh device, and an eighth device, the fifth device and the sixth device , the seventh device and the eighth device are arranged such that the distance from the other end of the power transmission device group in the predetermined direction increases in this order,
The sixth device and the seventh device transmit current so that the direction of the magnetic field generated in each of the power transmission coils when energized is opposite to the direction of the magnetic field generated in the power transmission coil of the fifth device when energized. The phase is adjusted,
In the eighth device, the phase of the current is adjusted such that the direction of the magnetic field generated in the power transmission coil of the eighth device when energized is the same as the direction of the magnetic field generated in the power transmission coil of the fifth device when energized. The contactless power supply device according to claim 1. 3. The power transmitting device group includes devices connected in a master-slave transmission format such that some of the power transmitting devices serve as master devices and other power transmitting devices serve as slave devices. The contactless power supply device described in .

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