Funding system

Abstract

Support system (1; 2), comprising: a plurality of conveying path units (11) forming a conveying path (10) along which a conveying body (16) moves, wherein the conveying path units (11) are each connected to a common direct current line (15), wherein each conveying path unit (11) of the plurality of conveying path units (11) comprises a drive unit (20) which is to be supplied with power from the DC line (15) in order to generate a driving force for moving the conveying body (16), and wherein of one or two or more conveying path units (11), to which no conveying body (16) is moved, at least one conveying path unit (11) of the plurality of conveying path units (11) performs a regeneration power supply for supplying regeneration power generated in the plurality of conveying path units (11) to the drive unit (20).

Description

Area

[0001] The present disclosure relates to a conveying system that transports an object. background

[0002] A conveyor system that transports a workpiece is used in a production line where factory automation has been implemented, such as a production line for assembling commercial products or a production line for packaging food products. In recent years, many conveyor systems have been used in which a conveyor path for transporting workpieces is divided into multiple zones, and a carrier on which a workpiece is placed is moved by a control device located in each zone. Such a conveyor system is known for its excellent production efficiency.

[0003] Some conveyor systems use a linear motor, which includes a carrier containing a magnet and a conveyor path with multiple coils. Some systems using the linear motor control the current flowing through each coil using an inverter circuit, such as a full-bridge or half-bridge inverter circuit. In such a system, it is important to appropriately manage the regenerative power generated in the coils when the carrier decelerates, either as consumption or recovery.

[0004] JP 2019 - 170 153 A discloses a conveying system comprising a carrier with a magnetic element and a conveying path with a plurality of magnetic coil arrangements, and recovering the regeneration energy in an energy storage arrangement provided at one or a plurality of points in the conveying path.

[0005] DE 11 2022 005 158 T5 discloses a conveying system in which regeneration power generated during a deceleration is used to accelerate a conveying body.

[0006] US patent 2015 / 0239015A1 discloses a conveying system in which conveying bodies are delayed for easier loading.

[0007] US 9 783 370 B2 discloses a conveying system in which conveying bodies are operated based on their weight.

[0008] US 9 050 896 B2 reveals an electromagnetic drive system for a rail vehicle.

[0009] US Patent 9,812,939 B2 discloses a conveying system with an improved drive for a conveying body during the transition between conveying path units. Overview of the invention; Problem to be solved by the invention

[0010] According to the technique disclosed in JP 2019-170 153 A, it is necessary to install the energy storage arrangement at each point in the conveying path where the carrier is decelerated. In cases where the point at which the carrier is decelerated is not defined, the energy storage arrangement must be installed at all points where the carrier can be decelerated. The more energy storage arrangements that need to be installed, the larger the conveying system and the higher its production costs. Accordingly, according to the conventional technique disclosed in JP 2019-170 153 A, a problem arises in that it is difficult to process the regeneration power appropriately.

[0011] The present disclosure was made with regard to the above and one of its objectives is to obtain a support system capable of processing the regeneration performance in a suitable manner. Means to solve the problem

[0012] To solve the problem described above and achieve the objective, a conveying system according to the present disclosure comprises a plurality of conveying path units forming a conveying path along which a conveyed body moves, the conveying path units each being connected to a common DC line. Each conveying path unit of the plurality of conveying path units includes a drive unit that is supplied with power from the DC line to generate a driving force for moving the conveyed body. Of one, two, or more conveying path units of the plurality of conveying path units to which no conveyed body is moving, at least one conveying path unit performs a regeneration power supply to supply regeneration power generated in the plurality of conveying path units. Effects of the invention

[0013] The conveying pathway unit according to the present disclosure achieves an effect such that suitable processing of the regeneration performance is possible. Brief description of the drawings Fig. Figure 1 is a diagram showing an exemplary configuration of a conveying system according to a first embodiment. Fig. Figure 2 is a diagram showing an exemplary configuration of a conveying path unit included in the conveying system according to the first embodiment. Fig. Figure 3 is a diagram illustrating a regeneration control system implemented by the conveying system according to the first embodiment. Fig. 4 is a diagram to illustrate the operation of each conveying path unit included in the conveying system according to the first embodiment. Fig. Figure 5 is a diagram showing an exemplary embodiment of a conveying system according to a second embodiment. Fig. 6 is a diagram to illustrate the operation of each conveying path unit included in the conveying system according to the second embodiment. Fig. Figure 7 is a diagram showing an exemplary configuration of the conveying path unit according to a modification of the second embodiment. Fig. Figure 8 is a diagram showing an exemplary configuration of a control system included in the conveying system according to a third embodiment. Fig. Figure 9 is a diagram showing an exemplary configuration of a learning device included in the control of the third embodiment. Fig. Figure 10 is a flowchart showing a processing sequence of the learning device included in the control of the third embodiment. Fig. Figure 11 is a diagram showing an exemplary configuration of a position command generation unit included in the control of the third embodiment. Fig. Figure 12 is a flowchart showing a processing sequence of the position command generation unit and a coil drive command generation unit included in the control of the third embodiment. Fig. Figure 13 is a diagram showing an exemplary configuration of a control circuit according to the first to third embodiments. Fig. Figure 14 is a diagram showing an exemplary configuration of a hardware circuit as a purpose-built circuit according to the first to third embodiments. Description of embodiments

[0014] The following section describes in detail a conveying system according to each embodiment with reference to the drawings. First embodiment.

[0015] Fig. Figure 1 is a diagram showing an exemplary configuration of a conveying system 1 according to a first embodiment. The conveying system 1 is a system used to transport an object. In the first embodiment, the conveying system 1 transports an object by moving a conveying body on which the object is placed.

[0016] The conveyor system 1 comprises a multitude of conveyor path units 11A, 11B, 11C, 11D, 11E, 11F, 11G and 11H, a controller 12, a DC power supply 13, and carriers 16A, 16B and 16C. In the following description, the conveyor path units 11A, 11B, 11C, 11D, 11E, 11F, 11G and 11H are each referred to as a conveyor path unit 11, unless otherwise specified.

[0017] The multitude of conveyor path units 11 are coupled together to form a conveyor path 10 along which the conveyed body moves. The multitude of conveyor path units 11 moves the conveyed body by exerting a driving force on it. Each of the carriers 16A, 16B, and 16C is a conveyed body. In the following description, the carriers 16A, 16B, and 16C are each referred to as a carrier 16 unless otherwise specified.

[0018] The one in Fig. The conveying path shown in Figure 10 is ring-shaped. This means that the one in the Fig. The conveyance path 10 shown in Figure 1 is a closed path. Conveyance path 10 of conveyance system 1 can also be an open path. This means that conveyance path 10 of conveyance system 1 can be a path with a starting point and an endpoint.

[0019] Conveyor path units 11A, 11B, 11E, and 11F are each straight conveyor path units 11, forming a straight path. Conveyor path units 11C, 11D, 11G, and 11H are each curved conveyor path units 11, forming a curved path and changing the direction of movement of the conveyed object. The conveyor path 10 can also consist only of the conveyor path units 11 forming a curved path, without including the conveyor path units 11 forming a straight path. Any shape can be implemented as the overall shape of the conveyor path.

[0020] The carrier 16 is attached to a side surface of the conveyor path 10. The carrier 16 moves along a guide rail provided on the side surface of the conveyor path 10. The carrier 16 moves along the side surface of the conveyor path 10 and stops at the side surface of the conveyor path 10. The conveyor system 1 according to the first embodiment is a linear motor with a moving magnet. The carrier 16 can move along a guide rail provided on an upper surface of the conveyor path 10. The carrier 16 comprises a permanent magnet forming a moving element, a permanent magnet for a linear encoder, and a guide roller that moves along the guide rail by rotation. In the Fig. Figure 1 shows the guide rail, the guide roller, the permanent magnet forming the moving element and the permanent magnet forming the linear encoder.

[0021] In the Fig. In the example shown, the conveying system 1 comprises eight conveying path units 11 and three carriers 16. There can be any number of conveying path units 11 included in the conveying system 1. That is, any number of conveying path units 11 can form the conveying path 10. The conveying system 1 only needs to include a plurality of conveying path units 11. Any number of carriers 16 can move along the conveying path 10. The conveying system 1 need only include one or a plurality of carriers 16.

[0022] Conveyor system 1 is not limited to a system comprising a linear motor and can be a system comprising a rotary motor. Conveyor system 1 can be a belt conveyor comprising a rotary motor and a belt that is rotated by the rotary motor. The belt conveyor moves a workpiece placed on the belt. Conveyor system 1 can be a roller conveyor comprising multiple rollers and a rotary motor that rotates the rollers. The roller conveyor moves a workpiece placed on the rollers.

[0023] The DC power supply 13 is connected to each conveyor path unit 11 via a DC power supply line 15. The DC power supply 13 is a power supply device or circuit that outputs a DC voltage. The DC power supply 13 provides power to each conveyor path unit 11. The conveyor path units 11 share the DC power supply 13.

[0024] The DC power supply line 15 carries a DC line on one positive side and a DC line on one negative side. The DC line on the positive side is referred to as a P line. The DC line on the negative side is referred to as an N line. The P line is connected to an anode of the DC power supply 13. The N line is connected to a cathode of the DC power supply 13. Hereafter, the lines are referred to as PN lines when referring to both the P line and the N line. Each of the plurality of conveyor path units 11 that form the conveyor path 10 is connected to a common DC line.

[0025] The conveyor system 1 has a configuration in which each conveyor path unit 11 is connected to the DC power supply 13 via a multipoint connection. The connection type between the conveyor path units 11 and the DC power supply 13 is not limited to a multipoint connection and can be a daisy-chain connection. In the Fig. In the example shown, the conveying system 1 comprises one DC power supply; however, the conveying system 1 can also comprise two or more DC power supplies 13. This means that a large number of power supply domains can be configured in the conveying system 1.

[0026] The controller 12 is connected to each conveyor path unit 11 via a data communication line 14. The controller 12 controls each of the plurality of conveyor path units 11. The data communication line 14 includes a line connecting the controller 12 and conveyor path unit 11A, which is one of the plurality of conveyor path units 11, as well as lines connecting adjacent conveyor path units 11 to each other. The conveyor system 1 has a configuration in which each conveyor path unit 11 is connected to the controller 12 via a daisy-chain connection. The connection type between the conveyor path units 11 and the controller 12 is not limited to the daisy-chain connection. The connection type between the conveyor path units 11 and the controller 12 can be a star connection, in which each conveyor path unit 11 is connected to the controller 12 via a communication interface.Alternatively, the conveying system 1 can include a large number of data communication lines 14 and each conveying path unit 11 and the control unit 12 can be directly connected to each other via the data communication line 14.

[0027] The controller 12 generates a position command specifying a position to which each carrier 16 is to be moved and generates a coil drive command based on the position command. The controller 12 issues the coil drive command to each conveyor path unit 11. Each conveyor path unit 11 operates one coil of the conveyor path unit 11 in accordance with the coil drive command. The controller 12 controls the movement of each carrier 16 by issuing the coil drive command to each conveyor path unit 11. The coil drive command can, for example, correspond to a current command, a speed command, or a thrust command.

[0028] One direction of movement of each carrier 16 is a clockwise direction in the Fig. 1 or a counterclockwise direction in the Fig. 1. Of the directions of movement, the clockwise direction is the most important. Fig. 1 is defined as a forward direction. Of the directions of movement, the counterclockwise direction is in the Fig. Arrow 17A is defined as a reverse direction. Arrow 17B indicates the forward direction.

[0029] A higher-level control device, such as a programmable logic controller (PLC), can be connected to the controller 12. The control device issues a command for sequence control to the controller 12. A human-machine interface (HMI) can also be connected to the controller 12. The HMI receives input from an operator. Furthermore, the HMI outputs information indicating the status of the conveyor system 1, either via a display or similar means. The controller 12 can obtain operational information for the carrier 16 from the higher-level control device or the HMI and generate the position command based on this operational information. The operational information specifies a sequence of movements for each of the multiple carriers 16 along the conveyor path 10.

[0030] Next, a configuration of the conveyor path unit 11 is described. Here, the configuration of the conveyor path unit 11 is described using the straight conveyor path unit 11 as an example. The curved conveyor path unit 11 differs from the straight conveyor path unit 11 in how the coils are arranged. The configuration of the curved conveyor path unit 11 is similar to that of the straight conveyor path unit 11, except for the difference in how the coils are arranged.

[0031] The Fig. Figure 2 is a diagram showing an exemplary embodiment of the conveying path unit 11, which is included in the conveying system 1 according to the first embodiment. Fig. Figure 2 shows the conveyor path unit 11 and permanent magnets 40 and 41, which are enclosed in the carrier 16. Permanent magnet 40 is a permanent magnet that forms a motion element. Permanent magnet 41 is a permanent magnet for a linear encoder.

[0032] The conveyor path unit 11 comprises a plurality of coils 20. Each coil 20 functions as a drive unit, which is supplied with power from the PN lines in order to generate a driving force. In the Fig. In the example shown, the conveyor path unit 11 comprises nine coils 20. There can be any number of coils included in the conveyor path unit 11. In the straight conveyor path unit 11, the plurality of coils 20 are arranged in one direction of the straight line. In the curved conveyor path unit 11, the plurality of coils 20 are arranged in one direction of the curvature.

[0033] Each of the coils of the conveyor path unit 11 is connected to an inverter circuit 21. The inverter circuit 21 includes switching elements and supplies power to the coil 20, whereby power conversion is performed by switching the switching elements. The switching elements are not shown. The inverter circuit 21 controls a current flowing through the coil 20. The inverter circuit 21 is a single-phase full-bridge inverter circuit or a single-phase half-bridge inverter circuit. The inverter circuit 21 can also be a three-phase inverter circuit connected to three coils 20. Each of the coils 20 of the conveyor path unit 11 includes not only a pure induction component but also a coil resistance.

[0034] Each inverter circuit 21 of the conveyor path unit 11 is connected between a P-line 31, which is a positive wiring of the DC power supply line 15, and an N-line 32, which is a negative wiring of the DC power supply line 15. Each inverter circuit 21 converts a direct current from the PN lines into an alternating current and supplies the alternating current to the coil 20. The inverter circuit 21 performs the power conversion from direct current power to alternating current power by switching the switching elements.

[0035] By supplying the power converted by the inverter circuit 21, the coil 20 generates an electromagnetic force that serves as a driving force for moving the carrier 16. A current sensor 22 is connected to each coil 20 of the conveyor unit 11. The current sensor 22 detects the actual value of the coil current, which is the current flowing through the coil 20. In the conveyor unit 11, a capacitor 23, which is an electrolytic capacitor, is connected between the P-line 31 and the N-line 32.

[0036] A current controller 24 is connected to the inverter circuit 21 and controls the inverter circuit 21. The current controller 24 calculates a voltage value to be applied to the coil 20 based on a current command value of the current flowing through the coil 20 and the actual value of the coil current detected by the current sensor 22. The current controller 24 transmits a pulse-width modulation (PWM) signal, obtained by comparing the calculated voltage value with a triangular waveform, to the inverter circuit 21. The current controller 24 transmits the PWM signal to the inverter circuit 21 to cause the inverter circuit 21 to perform the switching operation. Consequently, the current controller 24 applies a voltage to the coil 20, causing a current of the desired value to flow through the coil 20.The current controller 24 can calculate the voltage value of the voltage to be applied to the coil 20 by performing a proportional-integral differential control (PID control) of the voltage to be applied to the coil 20 based on a deviation between the current command value and the actual value of the current value.

[0037] The conveyor path unit 11 comprises a linear encoder 25, a processor 27, and a line voltage sensing unit 33. The line voltage sensing unit 33 detects a line voltage. The line voltage is a voltage on the PN line, which are DC lines, that is, a voltage between the P line 31 and the N line 32. The line voltage sensing unit 33 outputs a line voltage reading to the processor 27.

[0038] The linear encoder 25 is a detection unit for sensing the position of the carrier 16 on the conveyor path unit 11. The linear encoder 25 is provided on the conveyor path 10 by the plurality of conveyor path units 11 that are interconnected to form the conveyor path 10. The processor 27 is a central processing unit (CPU). The processor 27 can be an arithmetic device, a processing device, a microprocessor, a microcomputer, or a digital signal processor (DSP).

[0039] The linear encoder 25 incorporates a variety of position sensors 26. Each position sensor 26 is a sensor that detects a magnetic field, such as a Hall sensor or a magnetoresistive sensor. Each position sensor 26 detects a magnetic field of the permanent magnet 40 or a magnetic field of the permanent magnet 41. Here, the position sensor 26 is a Hall sensor to which two Hall elements are attached. The distance between the two Hall elements is equal to half a pole pitch of the permanent magnet 41. Each Hall element converts the magnetic field into an electrical signal and outputs the electrical signal. The electrical signal output by each Hall element changes with the movement of the carrier 16. The electrical signal output by one Hall element has a sine wave shape. The electrical signal output by the other Hall element has a cosine wave shape.

[0040] An analog-to-digital converter (ADC) integrated into processor 27 detects the sine and cosine waves. Processor 27 determines the position of the carrier 16 relative to the position sensor 26 by calculating the arctangent based on information about the sine and cosine waves. Consequently, processor 27 obtains position information indicating the position of the carrier 16.

[0041] Furthermore, the processor 27 receives the line voltage measurement from the line voltage sensing unit 33. The processor 27 controls the start and stop of the regeneration power supply by the inverter circuit 21. The regeneration power supply will be described later.

[0042] The conveyor path unit 11 includes a communication substation 28. The communication substation 28 is located on one side of the conveyor path unit 11. The data communication line 14 is connected to the communication substation 28. In a case where each conveyor path unit 11 and the controller 12 are connected by a daisy-chain connection, the communication substation 28 is configured to connect two data communication lines 14. For each of the plurality of coils 20 included in the conveyor path unit 11, the communication substation 28 receives a current command from the controller 12, specifying a current command value for a current to flow through the coil 20. The communication substation 28 obtains the position information from the processor 27 based on an output from each of the plurality of position sensors 26 included in the linear scale 25.The communication substation 28 transmits the acquired position information to the control unit 12.

[0043] For example, communication substation 28 performs fixed-cycle communication, in which a current command is received and position information is transmitted in a fixed cycle. Instead of fixed-cycle communication, communication substation 28 can perform aperiodic reception of the current command and transmission of the position information.

[0044] As described above, the conveyor path unit 11 primarily performs the function of excitation control of the coils 20 and the function of obtaining position information. All of the multiple conveyor path units 11 that make up the conveyor path 10 perform the excitation control of the coils 20 and the obtaining of position information similarly.

[0045] Next, an operation of the conveying system 1 is described, which is carried out by dividing the PN lines. It is assumed that in the Fig. In the conveying path units 11 shown in Figure 1, for example, carrier 16A and carrier 16B are in a running state, such as a state of acceleration. Additionally, it is assumed that in the Fig. In the conveying path units 11 shown, the carrier 16C is in a regeneration state, such as during a deceleration. In such states, if the regeneration power 16C is less than the sum of the operating power of carrier 16A and carrier 16B, the regeneration power is consumed as the operating power, and therefore an increase in line voltage due to the generation of regeneration power is prevented.

[0046] On the other hand, if carrier 16A, carrier 16B, and carrier 16C are all in a regeneration state, the regeneration power generated in these carriers is not consumed, causing the line voltage to rise. Furthermore, the line voltage also rises if one of carriers 16A, 16B, and 16C is in the operating state and another is in the regeneration state, and the regeneration power of the carrier 16 in the regeneration state is greater than the operating power of the carrier 16 in the operating state. An excessive rise in the line voltage reduces the service life of the capacitor 23 or damages it. Accordingly, the conveying system 1, according to the first embodiment, performs a regeneration control to consume regeneration power in the plurality of conveying path units 11, as described below.

[0047] This section describes the regeneration control performed by the conveying system 1. In conveying system 1, one, two, or more of the multiple conveying path units 11, to which the carrier 16 is not approaching, perform a regeneration power supply to provide the coils 20 with regeneration power generated in the multiple conveying path units 11. One, two, or more of the multiple conveying path units 11, to which the carrier 16 is not approaching, perform the regeneration power supply when the line voltage becomes greater than or equal to a preset first voltage threshold. The first voltage threshold is a line voltage value that serves as a reference for initiating the regeneration control. The first voltage threshold is preset in each conveying path unit 11 of conveying system 1.

[0048] The conveying path unit 11, which performs the regeneration power supply, stops the regeneration power supply when the line voltage becomes less than or equal to a second voltage threshold. The second voltage threshold is a line voltage value that serves as a reference for stopping the regeneration control. The second voltage threshold is preset in each conveying path unit 11 of conveying system 1. When the carrier 16 moves toward the conveying path unit 11 performing the regeneration power supply, the conveying path unit 11 stops performing the regeneration power supply. As described above, the conveying path unit 11 stops the regeneration power supply when the line voltage becomes less than or equal to the second voltage threshold or when the carrier 16 moves toward the conveying path unit 11.

[0049] Here, an example is given of a case in which, among the Fig. In Figure 1, the conveyor belt 16A begins to delay at conveyor belt units 11 shown above conveyor belt units 11C and 11D. Carrier 16C is stopped above conveyor belt units 11E and 11F. Carrier 16A begins to delay at conveyor belt unit 11A.

[0050] Fig. Figure 3 is a diagram illustrating the regeneration control performed by the conveying system 1 according to the first embodiment. Fig. Figure 3 shows a time diagram of the velocity of the carrier 16 at the conveying path unit 11 in the regeneration state, a line voltage Vpn, a regeneration power W1, and a regeneration power W2. The regeneration power W1 is the regeneration power supplied to the coils 20 of the conveying path units 11 where there is no carrier 16. The regeneration power W2 is the regeneration power supplied to the coils 20 of the conveying path units 11 where the carriers 16 are located. The velocity of the carrier 16 in the Fig. The velocity of carrier 16A shown in Figure 3 is that of carrier 16A. The conveyor path units 11 on which the carriers 16 are located are conveyor path units 11A, 11C, 11D, 11E, and 11F. The conveyor path units 11 on which no carrier 16 is located are conveyor path units 11B, 11G, and 11H.

[0051] A voltage value Von is a first voltage threshold. A voltage value Voff is a second voltage threshold. Here, the voltage values ​​Von, which are set in the respective conveying path units 11 of the conveying system 1, are the same. The voltage values ​​Voff, which are set in the respective conveying path units 11 of the conveying system 1, are the same.

[0052] When the carrier 16A begins to delay at time t1, regeneration power is generated in the coils 20 of the conveyor path unit 11A. When regeneration power is generated in the coils of the conveyor path unit 11A, the line voltage Vpn begins to rise from time t1. The processor 27 of each conveyor path unit 11 continuously monitors the result of the line voltage Vpn measurement by the line voltage measurement unit 33.

[0053] It is assumed that the line voltage Vpn, as in the Fig. Figure 3 shows that the voltage value Von is reached at time t2. The processor 27 of each of the conveyor path units 11B, 11G and 11H, on which there is no carrier 16, starts the regeneration power supply through the inverter circuit 21. The regeneration power W1, which is supplied to the coils 20 of each of the conveyor path units 11B, 11G and 11H, begins to increase from zero at time t2.

[0054] In a case where the inverter circuit 21 performs the regeneration power supply, the current control 24 performs current control such that a current corresponding to the rated current of the coil 20 continues to flow through the coil 20. The current flowing through the coil 20 is converted into heat by the coil resistance. The current is converted into heat by the coil 20, and thus the regeneration power W1 is consumed by the coil 20.

[0055] The regeneration power W1 is consumed, and as a result, the line voltage Vpn gradually decreases from the voltage value Von. It is assumed that the line voltage Vpn, as in the Fig. Figure 3 shows that the line voltage Voff drops from time t2 and the line voltage Vpn reaches the voltage value Voff at time t3. The processor 27 of each of the conveying path units 11B, 11G and 11H stops the regeneration power supply through the inverter circuits 21. In this, in the Fig. In the example shown, the regeneration power W1 begins to increase from time t2, is then held at a constant value, and begins to decrease from time t3. After that, the regeneration power W1 becomes zero.

[0056] In the conveying path units 11A, 11C, 11D, 11E and 11F, where the carriers 16 are located, the carriers 16 are moved and stopped. In the Fig. In the time series shown, the regeneration power W2, which is supplied to the coils 20 of each of the conveying path units 11A, 11C, 11D, 11E and 11F, remains at zero.

[0057] Fig. Figure 4 is a diagram illustrating the operation of each conveying path unit 11 included in the conveying system 1 according to the first embodiment. Fig. Figure 4 shows a table summarizing the presence or absence of the carrier 16 at each conveying path unit 11 and determining whether the regeneration power input to each conveying path unit 11 is to be carried out in the case of the above example. In the Fig. In column 4, “A”, “B”, ..., and “H” represent the feed path unit 11A, feed path unit 11B, ..., and feed path unit 11H, respectively. “Yes” in the “Regeneration Power Input” column indicates that regeneration power input is performed. “No” in the “Regeneration Power Input” column indicates that regeneration power input is not performed.

[0058] In a case where the carrier 16 is not detected by the linear encoder 25, the processor 27 of the conveyor path unit 11 recognizes that the carrier has not moved towards the conveyor path unit 11. In a case where the carrier is detected by the linear encoder 25, the processor 27 recognizes that the carrier 16 has moved towards the conveyor path unit 11. As in the Fig. As shown in Figure 4, each of the conveying path units 11B, 11G, and 11H, to which the carrier 16 is not moving, performs the regeneration power supply. Each of the conveying path units 11A, 11C, 11D, 11E, and 11F, to which the carrier 16 is moving, does not perform the regeneration power supply.

[0059] Conveyor system 1 prevents the line voltage Vpn from rising excessively above the voltage value Von by performing regeneration power input in the conveying path units 11 to which the carrier 16 is not approaching. When the line voltage Vpn in the conveying path units 11 performing regeneration power input drops to the voltage value Voff, conveying system 1 stops the regeneration power input to each conveying path unit 11. Conveyor system 1 consumes the regeneration power generated in the multitude of conveying path units 11 through this regeneration control. Conveyor system 1 can prevent an excessive increase in the line voltage Vpn.

[0060] In the description above, the voltage values ​​Von set in the respective conveying path units 11 of the conveying system 1 are the same, but the plurality of conveying path units 11 can include conveying path units 11 where different voltage values ​​Von are set. Any voltage value Von can be set individually for each of the plurality of conveying path units 11.

[0061] In the description above, the voltage values ​​Voff set in the respective conveying path units 11 of the conveying system 1 are the same, but the plurality of conveying path units 11 can include conveying path units 11 where different voltage values ​​Voff are set. Any voltage value Voff can be set individually for each of the plurality of conveying path units 11.

[0062] As described above, in conveying system 1, the first voltage threshold and / or the second voltage threshold can be individually set for each of the multiple conveying path units 11. Conveying system 1 can freely adjust the first voltage threshold and / or the second voltage threshold depending on a desired mode of regeneration power supply to be achieved by the conveying path unit 11.

[0063] The straight conveying path units 11 and the curved conveying path units 11 differ in the number of phases of the coils 20, the resistance values ​​of the coils 20, the size of the housing of the conveying path unit 11, or similar characteristics. Accordingly, for example, the first voltage threshold and / or the second voltage threshold can be set to different values ​​between the straight conveying path units 11 and the curved conveying path units 11. If the first voltage threshold and / or the second voltage threshold are set individually for each of the multiple conveying path units 11, the conveying system 1 can provide a suitable regeneration power consumption for each conveying path unit 11.

[0064] In the conveying path unit 11, where the number of phases of the coils 20 is large, the first voltage threshold can be lower than in the conveying path unit 11, where the number of phases of the coils 20 is small. Consequently, the conveying system 1 can prioritize the conveying path unit 11, which has coils 20 with a large number of phases, for performing the regeneration power supply. It should also be noted that the number of phases of the coils 20 is the number of coils 20 provided in a conveying path unit 11. Fig. Figure 2 shows the conveyor path unit 11, in which the number of phases of the coils 20 is nine.

[0065] In each conveying path unit 11 of conveying system 1, a power threshold, which is an upper limit of the regeneration power W1 allowed for the supply to each coil 20, is preset. The power thresholds set in the respective conveying path units 11 of conveying system 1 are the same. If the power supplied to each coil 20 of the conveying path unit 11 performing the regeneration power supply exceeds a preset power threshold, the conveying path unit 11 stops performing the regeneration power supply. For example, the power threshold could be I rate 2 ×R coil be set up, whereby I rate represents the nominal current of coil 20 and R coilThe coil resistance of coil 20 is represented. A value derived from an electronic thermal protection curve for each coil 20 can be set as the power threshold. The power threshold is not limited to these values ​​and any value can be set. By stopping the regeneration power supply in the conveying path unit 11 when the power supplied to each coil 20 exceeds the power threshold, the conveying system 1 can prevent the regeneration power from being wasted due to overheating of the coil 20.

[0066] In the description above, the power thresholds set in the respective conveying path units 11 of the conveying system 1 are the same, but the plurality of conveying path units 11 may include conveying path units 11 with different power thresholds set. Any power threshold can be set individually for each of the plurality of conveying path units 11. The conveying system 1 can freely set the power threshold based on a desired mode of regeneration power input to be achieved by the conveying path unit 11. For example, the power thresholds can be set to different values ​​between the straight conveying path units 11 and the curved conveying path units 11.If the power threshold is individually set for each of the multiple conveying path units 11, the conveying system 1 can provide a regeneration power input suitable for the configuration of each conveying path unit 11.

[0067] Let us assume that in funding system 1, for example, the one in the Fig. The carrier 16A shown in Figure 1 moves from conveying path unit 11A to conveying path unit 11H during the delay. When the entire carrier 16A has moved towards conveying path unit 11H and carrier 16A is not at conveying path unit 11A, conveying path unit 11A starts the regeneration power supply. Alternatively, conveying path unit 11H, which did not have carrier 16A at it before carrier 16A moved towards it, stops the regeneration power supply when carrier 16A begins to move towards conveying path unit 11H. As described above, conveying path units 11A and 11H switch between executing and stopping the regeneration power supply in response to the movement of carrier 16A.The conveying path units 11, which differ from conveying path units 11A and 11H, also perform a switching operation between executing and stopping the regeneration power supply in response to the movement of the carriers 16B and 16C. The conveying system 1 performs a switching operation of the conveying path units 11 that execute the regeneration power supply in response to the movement of the carrier 16, thereby consuming the regeneration power generated in the multitude of conveying path units 11 while the carriers 16 continue to move.

[0068] During regeneration power supply, the inverter circuit 21 operates at a switching frequency that is lower than the switching frequency set when the driving force acts on the carrier 16. In other words, regarding the frequencies at which the inverter circuit 21 operates, the switching frequency at which switching is performed by the inverter 21 during regeneration power supply is lower than the switching frequency at which switching is performed by the inverter 21 when the driving force acts on the carrier 16. Consequently, the conveying path unit 11 can reduce the noise generated during regeneration power supply with switching by the inverter 21.

[0069] According to the first embodiment, in the conveying system 1, one, two, or more conveying path units, to which the conveyed body is not moved, supply the regeneration power to the plurality of conveying path units 11. The conveying system 1 can consume the regeneration power even if the point at which the conveyed body is decelerated is undefined. Consequently, the conveying system 1 achieves an effect such that suitable processing of the regeneration energy is possible. Second embodiment.

[0070] In a second embodiment, an example is described in which, of the conveying path units 11 on which no carrier 16 is located, the conveying path units 11 adjacent to those on which the carriers 16 are located are excluded from the conveying path units 11 that perform the regeneration power supply. In the second embodiment, the carrier 16 can be moved uniformly when the carrier 16, moving on a particular conveying path unit 11, moves towards the adjacent conveying path unit 11 in a communication cycle. The communication cycle is a cycle of communication between the controller 12 and the conveying path units 11. In the second embodiment, the same components as in the first embodiment are designated with the same reference numerals, and configurations are mainly described that differ from those of the first embodiment.

[0071] Fig. Figure 5 is a diagram showing an exemplary configuration of a conveyor system 2 according to the second embodiment. In conveyor system 2, the processing by the controller 12 differs from that of the first embodiment. The configuration of conveyor system 2 is similar to the configuration of the one in the Fig. 1. Conveyor system shown. 1. The conveyor path units 11 each have a configuration that corresponds to the one shown in the Fig. The configuration shown is similar to the one in point 2.

[0072] In the Fig. In the example shown, conveyor system 2 comprises eight conveyor path units 11 and two carriers 16. Conveyor system 2 can contain any number of conveyor path units 11. That is, any number of conveyor path units 11 can form the conveyor path 10. Conveyor system 2 only needs to contain a plurality of conveyor path units 11. Any number of carriers 16 can move along the conveyor path 10. Conveyor system 2 need only contain one or a plurality of carriers 16.

[0073] The communication substation 28 of each conveyor path unit 11 receives the position information obtained by the processor 27 based on an output from each of the multiple position sensors 26, which are arranged on the linear scale 25. The communication substation 28 transmits the obtained position information to the controller 12 via the data communication line 14.

[0074] The controller 12 receives the position information transmitted by the communication substations 28 of the conveyor path units 11. The controller 12 combines the position information from the communication substations 28 of the conveyor path units 11 to obtain position information specifying the position of each carrier 16 on the conveyor path 10. Based on this position information, the controller 12 determines which conveyor path units 11 are to perform the regeneration power supply and which conveyor path units 11 are to stop the regeneration power supply.

[0075] The plurality of conveying path units 11 comprises a first conveying path unit and second conveying path units. The controller 12 excludes the first conveying path unit and the second conveying path units from the conveying path units 11 that are to perform the regeneration power supply. The plurality of conveying path units 11 comprises the conveying path units that are different from the first conveying path unit and the second conveying path units, and the controller 12 designates these other conveying path units as the conveying path units 11 that are to perform the regeneration power supply. The first conveying path unit 11 is the conveying path unit 11 on which the carrier 16, as the conveying body, is located. The second conveying path units are M conveying path units 11 and N conveying path units 11.The M conveying path units 11 are arranged in a first direction along the conveying path 10 adjacent to the first conveying path unit, and the N conveying path units 11 are arranged in a second direction adjacent to the first conveying path unit. The second direction, which is a direction along the conveying path 10, is opposite to the first direction. The first direction is a forward direction, indicated by arrow 17A. The second direction is a reverse direction, indicated by arrow 17B. Both M and N are integers of 1 or more. In the second embodiment, one or two or more conveying path units 11, to which the carrier 16 is not moving, perform the regeneration power supply in the conveying path 10.

[0076] Next, the operation of conveying system 2 is described for a case in which the regeneration power input is performed. Here, as an example, the operation of each conveying path unit 11 is described in a case in which the conveying system 2 is located in a Fig. 5 is in the state shown. If the conveyor system 2 is in the state shown in the Fig. In the state shown in Figure 5, support 16A is located at conveyor path unit 11A. Support 16B is located above conveyor path unit 11C and conveyor path unit 11D.

[0077] Fig. Figure 6 is a diagram illustrating the operation of each conveyor path unit 11 included in the conveyor system 2 according to the second embodiment. The controller 12 recognizes the first conveyor path units based on the referenced position information. In the diagram shown in the Fig. The first conveying path units shown are conveying path unit 11A, where carrier 16A is located, and conveying path units 11C and 11D, where carrier 16B is located.

[0078] Next, the controller 12 identifies the second conveyor path units based on the identified first conveyor path units. Here, M=1 and N=1 apply. In the Fig. In the example shown, each of the conveying path units 11B, 11E, and 11H is the second conveying path unit. The controller 12 excludes conveying path units 11A, 11C, and 11D, which are the first conveying path units, and conveying path units 11B, 11E, and 11H, which are the second conveying path units, from the conveying path units 11 that are performing the regeneration power supply. The controller 12 transmits an instruction to stop the regeneration power supply to each of the conveying path units 11A, 11B, 11C, 11D, 11E, and 11H. The instruction to stop the regeneration power supply is, for example, a signal in which a flag indicating the execution of the regeneration power supply is set to negative.

[0079] Next, the controller 12 identifies, from the multitude of conveyor path units 11 included in the conveyor system 2, those conveyor path units 11 that differ from the first conveyor path units and the second conveyor path units. In the Fig. In the example shown in Figure 5, each of the conveying path units 11F and 11G is conveying path unit 11, distinct from the first and second conveying path units. The controller 12 designates each of the conveying path units 11F and 11G as the conveying path unit 11 that performs the regeneration power supply. The controller 12 transmits an instruction to perform the regeneration power supply to each of the conveying path units 11F and 11G. The instruction to perform the regeneration power supply is, for example, a signal in which the flag indicating the execution of the regeneration power supply is set to positive.

[0080] The communication substation 28 of each of the conveyor path units 11A, 11B, 11C, 11D, 11E, and 11H receives the instruction to stop the regeneration power supply, which is sent by the controller 12. Each of the conveyor path units 11A, 11B, 11C, 11D, 11E, and 11H enters a state in which it does not perform the regeneration power supply, in accordance with the instruction to stop the regeneration power supply. Each of the conveyor path units 11C, 11D, 11E, and 11H performs normal operation to apply a driving force to the carrier 16.

[0081] The communication substation 28 of each of the conveyor path units 11F and 11G receives the instruction to execute the regeneration power supply, which is sent by the controller 12. Each of the conveyor path units 11F and 11G carries out the regeneration power supply in accordance with the instruction to execute the regeneration power supply.

[0082] M, defined as the number of second conveyor path units arranged in the first direction adjacent to the first conveyor path unit, and N, defined as the number of second conveyor path units arranged in the second direction adjacent to the first conveyor path unit, are preset. M and / or N can be calculated based on the velocity of the carrier 16 along the conveyor path 10.

[0083] Here, an example of a method for calculating M and N based on the speed of the carrier 16 along the conveyor path 10 is described. Here, the path length of the conveyor path unit 11 is denoted by L, the maximum speed of the carrier 16 is denoted by Vmax, and a communication cycle between the controller 12 and the conveyor path unit 11 is denoted by Tcyc. Both M and N are obtained by rounding up the decimal places of L / (Vmax×Tcyc).

[0084] As described above, in the second embodiment, the conveyor system 2 excludes not only the first conveyor path units, on which the carrier 16 is located, but also the second conveyor path units adjacent to the first conveyor path units from the conveyor path units 11 that perform the regeneration power supply. When the carrier 16, moving along the first conveyor path unit, approaches the adjacent second conveyor path unit, the carrier 16 moves towards the second conveyor path unit, which performs normal operation for applying the drive force to the carrier 16. Consequently, in conveyor system 2, no carrier moves towards the conveyor path unit 11 that performs the regeneration power supply in the communication cycle, thus allowing the carrier 16 to move uniformly in a section where the conveyor path units 11 are adjacent to one another.

[0085] In the description above, M and N are integers of 1 or more; however, M and / or N can be zero. This means that the second conveying path units must be at least one of the following: one, two, or more conveying path units 11 arranged in the first direction adjacent to the first conveying path unit, and one, two, or more conveying path units 11 arranged in the second direction adjacent to the first conveying path unit. The conveying system 2 can switch M and N between zero and an integer of 1 or more for each communication cycle based on the direction of movement of the carriers 16 for each communication cycle.

[0086] The controller 12 can exclude the first conveyor path unit 11, the one on which the conveyed body is located, and the second conveyor path unit 11, which is one, two, or more of the conveyor path units 11 arranged in the direction of movement of the conveyed body on conveyor path 10 adjacent to the first conveyor path unit, from the conveyor path units 11 that perform the regeneration power supply. The second conveyor path unit, arranged adjacent to and downstream of the first conveyor path unit in the direction of movement, performs the normal operation of applying the drive force to the carrier 16. The conveyor system 2 can move the carrier 16 uniformly in a section where the conveyor path units 11 are located next to each other. Furthermore, in this case, the number of second conveyor path units can be calculated based on the speed of the carrier 16 on conveyor path 10.

[0087] According to the second embodiment, the conveying system 2 excludes the first conveying path unit and the second conveying path units from the conveying path units 11 that perform the regeneration power supply, thereby ensuring the normal operation of the action of the driving force on the carrier 16 in the first conveying path unit and the second conveying path units. Consequently, the conveying system 2 can move the carrier 16 uniformly. Additionally, the conveying system 2 supplies the regeneration power to the conveying path units 11 that are distinct from the first and second conveying path units, from the plurality of conveying path units 11. Consequently, the conveying system 2 can process the regeneration power appropriately.

[0088] Fig. Figure 7 is a diagram showing an exemplary configuration of the conveying path unit 11 according to a modification of the second embodiment. The conveying path unit 11 according to the modification of the second embodiment includes a temperature sensor 34. The controller 12 determines the conveying path unit 11 that is to perform the regeneration power supply based on a temperature reading from the temperature sensor 34 of each of the plurality of conveying path units 11.

[0089] In each of the conveying path units 11 that perform the regeneration power supply, the temperature within the conveying path unit 11 rises due to the consumption of the regeneration power in the coils 20. The controller 12 compares the temperatures of the respective conveying path units 11 of the conveying system 2. The controller 12 determines, from the multitude of conveying path units 11, one, two, or more conveying path units 11 in ascending order of temperature as the ones that perform the regeneration power supply. Consequently, the conveying system 2 can equalize the temperatures of the respective conveying path units 11. By equalizing the temperatures of the respective conveying path units 11, it is possible to extend the service life of a component of each conveying path unit 11 that deteriorates under the influence of temperature.The controller 12 can determine a temperature threshold in advance, which is to be compared with the temperature measurement result by the temperature sensor 34 of each of the plurality of conveying path units 11, and when the conveying path units 11 perform the regeneration power input, determine one or two or more conveying path units 11 in which the temperature measurement result by the temperature sensor 34 is less than or equal to the temperature threshold. Third embodiment.

[0090] In a third embodiment, an example is described in which machine learning is applied to the generation of a position command that is issued by the controller 12 to each conveyor path unit 11. Based on the operating information of each carrier 16, the controller 12 generates a position command that increases the number of conveyor path units 11 performing the regeneration power supply, based on a trained model.

[0091] For example, suppose that operational information is obtained indicating that carrier 16 will reach a target position located 3 m from its current position two seconds after a certain time. In this case, any pattern can be used as a position command pattern to move carrier 16. One possible pattern is one in which carrier 16 is moved by trapezoidal acceleration / deceleration between the start point and the end point of the two-second period. Examples of other patterns include one in which carrier 16 is moved by trapezoidal acceleration / deceleration for one second from the start point and is stopped for the remaining one second, and another in which carrier 16 is stopped for one second from the start point and is moved by trapezoidal acceleration / deceleration for the remaining one second.There are infinitely many patterns that can be used as the pattern for the position command.

[0092] The conveying system 2 can increase the number of conveying path units 11 performing the regeneration power supply in each control cycle by appropriately adjusting the position command pattern for each carrier 16. This means that in the conveying system 2, the regeneration power supplied by a conveying path unit 11 can be reduced by increasing the number of conveying path units 11 performing the regeneration power supply, thereby preventing an excessive temperature rise of the conveying path unit 11. In the third embodiment, a position command that increases the number of conveying path units 11 performing the regeneration power supply is derived by a machine learning method.

[0093] The configuration of the conveying system 2 according to the third embodiment is similar to the configuration of the one in the Fig. The conveyor system 2 shown in Figure 5. The controller 12 of the conveyor system 2 according to the third embodiment receives position information indicating the position of each carrier 16 on the conveyor path 10, similar to the case of the second embodiment. The third embodiment differs from the second embodiment in that machine learning components are added to the controller 12.

[0094] Fig. Figure 8 is a diagram showing an exemplary configuration of the controller 12 included in the conveyor system 2 according to the third embodiment. The controller 12 includes a learning device 51, a storage unit 52 for trained models, a position command generation unit 53, and a coil drive command generation unit 54.

[0095] The learning device 51 learns a relationship between the operational information of each of the plurality of carriers 16 included in the conveyor system 2 and the position command, which increases the number of conveyor path units 11, thereby increasing the regeneration power input. The operational information specifies the timing of the movement of each of the plurality of carriers 16 along the conveyor path 10. The position command specifies a position to which each carrier 16 is moved. The learning device 51 outputs a trained model, which is a result of the learning process. The trained model storage unit 52 stores the trained model.

[0096] For each of the multiple carriers 16 included in the conveyor system 2, the position command generation unit 53 generates a position command specifying a position to which the carrier 16 is moved. The position command generation unit 53 reads a trained model from the trained model storage unit 52. The position command generation unit 53 infers a position command that increases the number of conveyor path units 11 performing the regeneration power supply by inputting the operational information into the trained model. The position command generation unit 53 generates the position command through this inference.

[0097] The coil drive command generation unit 54 generates a coil drive command based on the position command. The controller 12 controls the movement of each carrier 16 by outputting the coil drive command to each conveyor path unit 11.

[0098] Fig. Figure 9 is a diagram showing an exemplary configuration of the learning device 51, which is included in the controller 12 of the third embodiment. The learning device 51 comprises a data reference unit 61 and a model generation unit 62. The data reference unit 61 obtains training data and generates a data set obtained by combining the training data. The training data consists of operational information and a position command. That is, the data reference unit 61 obtains training data that includes the operational information and the position command.

[0099] Model generation unit 62 creates a trained model using the training data. Model generation unit 62 creates a trained model that is used to infer a position command based on operational information, using the training data.

[0100] Any known algorithm, such as supervised learning, unsupervised learning, or reinforcement learning, can be used as a learning algorithm by Model Generation Unit 62. As an example, a case is described in which reinforcement learning is used for a learning algorithm employed by Model Generation Unit 62. Reinforcement learning is a type of learning in which a subject, acting as an agent in an environment, observes the current state and decides which action to take. The agent receives a reward from the environment by choosing an action and learns a strategy to maximize the reward over a series of actions. Representative methods of reinforcement learning include Q-learning, TD-learning, and similar techniques.For example, in a Q-learning case, an action value table, which is a general update formula for an action value function Q(s,a), is expressed by the following formula (1). The action value function Q(s,a) represents an action value Q, which is the value of an action of selecting an action "a" in an environment "s". Formula 1: Q(st,at)←Q(st,at)+α(rt+1+γmaxaQ(st+1,at)−Q(st,at))

[0101] In formula (1) “s” represents t “an environment at time “t”. “a t “ represents an action at time “t”. The action “at” changes the environment to “s”. t+1 “.” “r t+1 “ represents a reward obtained by changing the environment. “y” represents a discount factor. “α” represents a learning coefficient. The operational information is the environment “s”. t “The position command is the action “a t “.

[0102] The update formula expressed by formula (1) increases an action value Q if the action value of the best action "a" at time "t+1" is greater than the action value Q of action "a" being performed at time "t", and decreases the action value Q if the opposite is true. In other words, the action value function Q(s,a) is updated so that the action value Q of an action "a" at time "t" approaches a best action value at time "t+1". Consequently, a best action value in a given environment gradually propagates to action values ​​in previous environments.

[0103] The model generation unit 62 comprises a reward calculation unit 63 and a function update unit 64. The reward calculation unit 63 calculates a reward based on the data set. The function update unit 64 updates a function for determining a position command in accordance with the reward calculated by the reward calculation unit 63.

[0104] Specifically, the reward calculation unit 63 calculates a reward "r" based on the number of conveying path units 11 performing the regeneration power input for each control cycle. For example, a reference number of conveying path units 11, which is a reference to the number of conveying path units 11 performing the regeneration power input, is predetermined, and the reward calculation unit 63 increases the reward "r" in a case where the number of conveying path units 11 performing the regeneration power input is greater than the reference number. The reward calculation unit 63 increases the reward "r" by adding "1", which is a value of the reward. Note that the value of the reward is not limited to "1".On the other hand, the reward calculation unit 63 reduces the reward "r" in a case where the number of conveying path units 11 performing the regeneration power input is less than the reference number. The reward calculation unit 63 reduces the reward "r" by adding "-1", which is a value of the reward. It should be noted that the value of the reward is not limited to "-1". Additionally, any number can be set as the reference number. The reference number can be set, for example, taking into account the magnitude of the regeneration power or the generation frequency of the regeneration power, based on the total number of conveying path units 11 and the total number of carriers 16 forming the conveying system 2.

[0105] The function update unit 64 updates a function, which is a model for determining a position command, in accordance with the reward calculated by the reward calculation unit 63. The function can be updated in accordance with the data set, such as by updating the action value table. The action value table is a data set in which any action and its corresponding action value are stored together in tabular form. For example, in the case of Q-learning, an action value function Q(s) is used. t , a t ), which is expressed by the above formula (1), is used as a function to determine the position command.

[0106] Fig. Figure 10 is a flowchart showing a processing sequence of the learning device 51, which is included in the controller 12 of the third embodiment. A reinforcement learning method for updating the action value function Q(s,a) is described with reference to the flowchart of the Fig. 10 described.

[0107] In step S11, the learning device 51 receives operating information and a position command from the data reference unit 61. This means that the learning device 51 receives training data. The data reference unit 61 outputs a data set containing the training data collectively to the model generation unit 62.

[0108] In step S12, the learning device 51 calculates a reward using the reward generation unit 63. The reward calculation unit 63 calculates a reward based on a combination of the operational information for each carrier 16 and a position command for each carrier 16. The reward calculation unit 63 increases or decreases the reward based on the number of conveying path units 11 performing the regeneration power supply for each control cycle.

[0109] In step S13, the learning device 51 updates the action value function through the function update unit 64. The function update unit 64 updates the action value function Q(s,a) based on the reward calculated in step S12. The learning device 51 updates the action value function Q(s t ,a t ), which is stored in memory unit 52 for trained models.

[0110] In step S14, learning unit 51 determines, via function update unit 64, whether the action value function Q(s,a) has converged. Function update unit 64 determines that the action value function Q(s,a) has converged if the action value function Q(s,a) is no longer updated in step S13.

[0111] If the function update unit 64 determines that the action value function Q(s,a) has not converged (step S14, No), the learning device 51 returns to step S11 in the sequence. On the other hand, the learning device 51 terminates the processes in accordance with the one specified in the Fig. The sequence shown in Figure 10 occurs when the function update unit 64 determines that the action value function Q(s,a) has converged (step S14, Yes). It should be noted that the learning device 51 can continue learning by retracing its steps from step S13 to step S11 without performing the determination in step S14. The trained model memory unit 52 stores a trained model that is the generated action value function Q(s,a).

[0112] The third embodiment describes a case in which reinforcement learning is used for the learning algorithm employed by the learning device 51; however, various learning methods can also be used for the learning algorithm. The learning device 51 can perform machine learning using a known learning algorithm, such as deep learning, a neural network, genetic programming, inductive logic programming, or a support vector machine.

[0113] The in the Fig. 8 and Fig. The learning device 51 shown in Figure 9 is a device integrated into the controller 12. The learning device 51 can be a device outside the controller 12. The learning device 51, which is a device outside the controller 12, is included in the conveyor system 2. The learning device 51 can be a device connectable to the controller 12 via a network. The learning device 51 can be a device located on a cloud server.

[0114] The learning device 51 can learn the position command that increases the number of conveyor path units 11 performing the regeneration power input, in accordance with a dataset created for a variety of conveyor systems 2. The learning device 51 can obtain training data from a variety of conveyor systems 2 operating at the same location, or it can obtain training data from a variety of conveyor systems 2 located at different locations. The training data can be collected from a variety of conveyor systems 2 operating independently at a variety of locations. After the collection of training data from such a variety of conveyor systems 2 has started, a new conveyor system 2 can be added as a target from which to collect training data.Additionally, after the collection of training data from the multitude of support systems 2 has started, some of the multitude of support systems 2 can be excluded from the targets from which the training data is collected.

[0115] The learning device 51, which has trained one support system 2, can train other support systems 2 that are different from the first support system 2. The learning device 51, which performs the learning for the other support systems 2, can update the trained model by relearning on the other support systems 2.

[0116] Fig. Figure 11 is a diagram showing an exemplary configuration of the position command generation unit 53, which is included in the controller 12 of the third embodiment. The position command generation unit 53 functions as an inference unit that infers a position command based on operational information. The position command generation unit 53 includes a data reference unit 65 and an inference unit 66.

[0117] The data reference unit 65 receives inference data. The inference data is operational information for each of the multitude of carriers 16 included in the conveyor system 2. The inference unit 66 reads the trained model generated by the learning device 51 from the trained model storage unit 52. The inference unit 66 infers a position command by inputting the inference data into the trained model. The inference unit 66 outputs the position command, which is a result of the inference, to the coil drive command generation unit 54. The coil drive command generation unit 54 generates a coil drive command based on the position command.

[0118] Fig. Figure 12 is a flowchart showing a processing sequence of the position command generation unit 53 and the coil drive command generation unit 54, which are included in the control 12 of the third embodiment.

[0119] In step S21, the position command generation unit 53 obtains the operating information of each carrier 16 from the data reference unit 65. The data reference unit 65 outputs the obtained operating information to the inference unit 66.

[0120] In step S22, the position command generation unit 53 generates a position command by inputting the operating information of each carrier 16 into the trained model in the inference unit 66. In step S23, the inference unit 66 outputs the position command to the coil drive command generation unit 54. In step S24, the coil drive command generation unit 54 generates a coil drive command based on the position command. Thus, the position command generation unit 53 and the coil drive command generation unit 54 terminate the processes in accordance with the [relevant] Fig. The processes shown in Figure 12. The controller 12 transmits the coil drive command generated by the coil drive command generation unit 54 to each conveyor path unit 11 via the data communication line 14.

[0121] According to the third embodiment, the conveying system 2 comprises the learning device 51 and the position command generation unit 53, which is an inference device, making it possible to derive the position command that increases the number of conveying path units 11 that perform the regeneration power supply. Consequently, the conveying system 2 can process the regeneration power in a suitable manner.

[0122] An example was described in which machine learning is used to generate the position command in the conveyor system 2 according to the second embodiment. The machine learning described in the third embodiment can also be used to generate the position command in a case where the regeneration power supply is performed in the conveyor path units 11 to which the carrier 16 is not moving, as in the first embodiment. The conveyor system 2 can generate the position command by a method different from machine learning.

[0123] Next, hardware implementing the controller 12 according to the first to third embodiments is described. The controller 12 is implemented by a processing circuit. The processing circuit can be a circuit that is a processor executing software, or it can be a dedicated circuit.

[0124] In a case where the processing circuit is implemented by software, the processing circuit is, for example, one in the Fig. 13 control circuits shown. Fig. Figure 13 is a diagram showing an exemplary configuration of a control circuit 80 according to the first to third embodiments. The control circuit 80 comprises an input unit 81, a processor 82, a memory 83, and an output unit 84. The input unit 81 is an interface circuit that receives data input to the control circuit 80 from the outside and forwards the data to the processor 82. The output unit 84 is an interface unit that outputs data from the processor 82 or the memory 83 to the outside, relative to the control circuit 80.

[0125] In a case where the processing circuit is located in the Fig. In the control circuit 80 shown in Figure 13, the control 12 is implemented by software, firmware, or a combination of both. The software or firmware is described as a program and stored in memory 83. The processing circuit implements functions of the control 12 through the processor 82, which reads and executes a program stored in memory 83. This means that the processing circuit includes memory 83 for storing a program that, as a result, executes a process of the control 12. It is also noted that these programs can cause a computer to execute processes and procedures of the control 12.

[0126] The processor 82 is a CPU. The processor 82 can be a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, a processor, or a DSP. The memory 83 corresponds, for example, to non-volatile or volatile semiconductor memory, such as random-access memory (RAM), read-only memory (ROM), flash memory, erasable programmable read-only memory (EPROM), or electrically erasable programmable read-only memory (EEPROM, registered trademark), magnetic storage, a floppy disk, optical storage, a CD (Compact Disk), a MiniDisc, or a DVD (Digital Versatile Disk).

[0127] Fig. 13 is an example of hardware in a case where the control 12 is implemented by the processor 82 and the memory 83 for general purposes, but the control 12 may be implemented by a purpose-built hardware circuit. Fig. Figure 14 is a diagram showing an exemplary configuration of a hardware circuit 85 as a purpose-built circuit according to the first to third embodiments.

[0128] The hardware circuit 85, as a purpose-built circuit, comprises the input unit 81, the output unit 84, and a processing circuit 86. The processing circuit 86 is a single circuit, a composite circuit, a programmable logic controller (PLC), a parallel programmable logic controller (PLC), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a circuit obtained by a combination thereof. The functions of the controller 12 can be implemented separately by the processing circuit 86, or the functions can be implemented jointly by the processing circuit 86. The controller 12 can be implemented by a combination of the controller circuit 80 and the hardware circuit 85.

[0129] The configurations described above in the respective embodiments are merely examples of the content of this disclosure. The configurations of the respective embodiments can be combined with other known technologies. The configurations of the respective embodiments can be combined in a suitable manner. Some of the configurations of the respective embodiments can be omitted or modified without departing from the core of this disclosure. Reference symbol list 1, 2 Conveyor system; 10. Funding path; 11, 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H Conveyor path unit; 12 Control; 13 DC power supply; 14 Data communication lines; 15 DC power supply lines; 16, 16A, 16B, 16C carriers; 17A, 17B Arrow; 20 coils; 21 Inverter circuit; 22 Current sensor; 23 Capacitor; 24 Power control; 25 linear encoders; 26 Position sensor; 27.82 processor; 28 Communication substation; 31 P-line; 32 N-line; 33 Line voltage detection unit; 34 Temperature sensor; 40, 41 Permanent magnet; 51 Learning device; 52 storage units for trained models; 53 Position command generation unit; 54 Coil drive command generation unit; 61.65 data reference unit; 62 Model generation unit; 63 Reward calculation unit; 64 Function update unit; 66 Inference unit; 80 Control circuit; 81 Input unit; 83 storage locations; 84 output units; 85 Hardware circuitry; 86 processing circuit.

Claims

[1] Support system (1; 2), comprising: a plurality of conveying path units (11) forming a conveying path (10) along which a conveying body (16) moves, wherein the conveying path units (11) are each connected to a common direct current line (15), wherein each conveying path unit (11) of the plurality of conveying path units (11) comprises a drive unit (20) which is to be supplied with power from the DC line (15) in order to generate a driving force for moving the conveying body (16), and wherein of one or two or more conveying path units (11), to which no conveying body (16) is moved, at least one conveying path unit (11) of the plurality of conveying path units (11) performs a regeneration power supply for supplying regeneration power generated in the plurality of conveying path units (11) to the drive unit (20). [2] Conveyor system (1; 2) according to claim 1, wherein the conveying path units (11) each comprise a line voltage detection unit (33) for detecting a line voltage (Vpn) which is a voltage of the DC line (15), and wherein of one or two or more conveying path units (11) to which the conveying body (16) is not moved, at least one conveying path unit (11) performs a regeneration power supply when the line voltage (Vpn) becomes greater than or equal to a preset first voltage threshold (Von). [3] Conveying system (1; 2) according to claim 2, wherein the conveying path units (11) that perform the regeneration power supply stop the regeneration power supply when the line voltage (Vpn) becomes less than or equal to a second voltage threshold (Voff) which is less than the first voltage threshold (Von). [4] Conveyor system (1; 2) according to claim 3, wherein the first voltage threshold (Voff) and / or the second voltage threshold (Voff) is individually set for each of a plurality of conveying path units (11). [5] Conveying system (1; 2) according to one of claims 1 to 4, wherein when the conveying body (16) is moved towards the conveying path unit (11) which performs the regeneration power supply, the conveying path unit (11) stops the execution of the regeneration power supply. [6] Conveying system (1; 2) according to any one of claims 1 to 5, wherein the conveying path unit (11) stops the execution of the regeneration power supply when power supplied to the drive unit (20) of the conveying path unit (11) that performs the regeneration power supply exceeds a preset power threshold. [7] Conveying system (1; 2) according to claim 6, wherein the power threshold is individually set for each of a plurality of conveying path units (11). [8] Conveyor system (1; 2) according to any one of claims 1 to 7, wherein the conveying path (10) is equipped with a sensor unit (25) for detecting a position of the conveying body (16), and wherein of the multitude of conveying path units (11) one conveying path unit (11) which is detected by a result of the detection by the sensor unit (25) as a conveying path unit (11) to which the conveying body (16) is not moved, performs the regeneration power supply. [9] Conveying system (2) according to any one of claims 1 to 7, comprising: a controller (12) for controlling each of the multiple conveying path units (11), wherein the control (12) determines the conveying path unit (11) for the execution of the regeneration power supply on the basis of position information which specifies a position of the conveying body (16) on the conveying path (10). [10] Conveyor system (2) according to claim 9, wherein the plurality of conveying path units (11) comprises a first conveying path unit (11A; 11C; 11D) and a second conveying path unit (11B; 11E; 11H), wherein the first conveying path unit (11A; 11C; 11D) is the conveying path unit (11) on which the conveying body (16) is located, wherein the second conveying path unit (11B; 11E; 11H) is one or two or more of the conveying path units (11) arranged in the conveying path (10) adjacent to the first conveying path unit (11A; 11C; 11D), and wherein the control (12) excludes the first conveying path unit (11A; 11C; 11D) and the second conveying path unit (11B; 11E; 11H) from the conveying path units (11) to perform the regeneration power supply. [11] Conveyor system (2) according to claim 10, wherein the number of second conveying path units (11B; 11E; 11H) arranged in a first direction (A) along the conveying path (10) next to the first conveying path unit (11A; 11C; 11D), and / or the number of second conveying path units (11B; 11E; 11H) arranged in a second direction (B) opposite to the first direction along the conveying path (10) next to the first conveying path unit (11A; 11C; 11D), is calculated on the basis of a velocity of the conveying body (16) on the conveying path (10). [12] Conveyor system (2) according to claim 9, wherein the plurality of conveying path units (11) comprises a first conveying path unit (11A; 11C; 11D) and a second conveying path unit (11B; 11E; 11H), wherein the first conveying path unit (11A; 11C; 11D) is the conveying path unit (11) on which the conveying body (16) is located, wherein the second conveying path unit (11B; 11E; 11H) is one or two or more of the conveying path units (11) that are arranged in the conveying path (10) in a direction of movement of the conveying body (16) adjacent to the first conveying path unit (11A; 11C; 11D), and wherein the control (12) excludes the first conveying path unit (11A; 11C; 11D) and the second conveying path unit (11B; 11E; 11H) from the conveying path units (11) to perform the regeneration power supply. [13] Conveying system (2) according to one of claims 10 to 12, wherein the number of second conveying path units (11B; 11E; 11H) is calculated on the basis of a velocity of the conveying body (16) on the conveying path (10). [14] Conveyor system (2) according to any one of claims 9 to 13, wherein the conveying path units (11) each include a temperature sensor (34), and wherein the control (12) determines the conveying path units (11) to perform the regeneration power supply based on a result of the temperature measurement by the temperature sensor (34) of each of the plurality of conveying path units (11). [15] Conveyor system (1; 2) according to any one of claims 1 to 14, wherein the conveying path units (11) each comprise an inverter circuit (21) to supply power to the drive unit (20), in which a power conversion is carried out by switching, and wherein the inverter circuit (21) operates at a switching frequency that is lower than a switching frequency that is set when the driving force acts on the conveying body (16) during the regeneration power supply. [16] Conveying system (2) according to any one of claims 1 to 15, wherein the conveying body (16) comprises a plurality of conveying bodies (16A; 16B; 16C), and wherein the conveying system (2) comprises: a learning device (51), comprising: a data reference unit (61) for obtaining training data comprising operational information and a position command, wherein the operational information is information specifying a time sequence of the movement of each of the conveying bodies (16A; 16B; 16C) along the conveying path (10), wherein the position command specifies for each of a plurality of the conveying bodies (16A; 16B; 16C) a position to which the conveying body is moved, and a model generation unit (62) for generating a trained model based on the training data, wherein the trained model is to be used to infer the position command from the operational information. [17] Conveying system (2) according to any one of claims 1 to 15, wherein the conveying body (16) comprises a plurality of conveying bodies (16A; 16B; 16C), and wherein the conveying system (2) comprises: a controller (12) for controlling each of the plurality of conveying path units (11), wherein the controller (12) comprises a position command generation unit (53) for generating a position command which specifies for each of a plurality of the conveying bodies (16A; 16B; 16C) a position to which the conveying body is moved, the position command generation unit (53) comprises: a data reference unit (55) for obtaining operational information, which is information that specifies a temporal sequence of the movement of each of the conveying bodies (16A; 16B; 16C) along the conveying path (10); and an inference unit (66) for inferring a position command by inputting the operating information into a trained model for inferring the position command from the operating information, wherein the position command specifies for each of a plurality of conveying bodies (16A; 16B; 16C) a position to which the conveying body is moved. [18] Conveying system (1; 2) according to any one of claims 1 to 17, comprising: the one or the multitude of conveying bodies (16; 16A; 16B; 16C), wherein the drive unit comprises a coil (20) to which power is supplied from the DC line (15) in order to generate an electromagnetic force which is the driving force, and wherein the conveying body (16; 16A; 16B; 16C) is provided with a permanent magnet (40; 41).

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