Conveying system

Abstract

A transport system (1) is provided with a plurality of transport path units (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H) that constitute a transport path (10) in which a transport body moves, and that are each connected to a common DC bus. Each of the plurality of transport path units (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H) has a drive unit that generates power for moving the transport body by power supplied from the DC bus line. And one or at least one of two or more transport path units from among the plurality of transport path units (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H) into which a transport body does not enter, performs regenerative power supply for supplying the regenerative power generated in the plurality of transport path units (11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H) to the drive unit.

Description

Technical Field

[0001] The invention relates to a conveying system for conveying objects. Background Art

[0002] In production lines that introduce factory automation, such as production lines for assembling industrial products or production lines for packaging food, conveyor systems for conveying workpieces are generally used. In recent years, conveyor systems that divide the conveying path for conveying workpieces into multiple areas and drive a trolley carrying the workpiece through a control device arranged in each area are often used. This conveyor system is known to be one of the conveyor systems with excellent production efficiency.

[0003] A linear motor is sometimes used in a conveying system, and the linear motor includes a carriage having a magnet and a conveying path having a plurality of coils. In a conveying system using a linear motor, the current flowing through each coil is sometimes controlled by an inverter circuit such as a full-bridge inverter circuit or a half-bridge inverter circuit. In such a conveying system, it is important to appropriately process the regenerative power generated by the coil when the carriage decelerates, such as in the form of consumption or recovery.

[0004] Patent Document 1 discloses a conveying system including a carriage having a magnetic element and a conveying path having a plurality of magnetic coil assemblies, and recovering regenerative energy in energy storage assemblies provided at one or more points in the conveying path.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-170153 Summary of the invention

[0006] According to the technology involved in Patent Document 1, it is necessary to set up energy storage assemblies at each point where the trolley decelerates in the conveying path. In the case where the point where the trolley decelerates is uncertain, energy storage assemblies must be set up at all points where the trolley may decelerate. The more energy storage assemblies that need to be set up, the larger the conveying system becomes, and the higher the production cost of the conveying system. Therefore, according to the prior art involved in Patent Document 1, there is a problem that it is difficult to properly handle regenerative power.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to obtain a transmission system capable of appropriately handling regenerative electric power.

[0008] In order to solve the above-mentioned problems and achieve the purpose, the conveying system involved in the present invention has a plurality of conveying path units, which constitute a conveying path for a conveying body to move, and each of which is connected to a common DC bus. Each of the plurality of conveying path units has a driving unit, which generates power to move the conveying body by supplying power from the DC bus. One of the plurality of conveying path units into which the conveying body does not enter or at least one of two or more conveying path units performs regenerative power supply of regenerative power generated in the plurality of conveying path units to the driving unit.

[0009] Effects of the Invention

[0010] The transmission system according to the present invention has an effect of being able to appropriately process regenerative electric power. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a diagram showing a configuration example of a transport system according to the first embodiment.

[0012] Figure 2 This is a diagram showing a configuration example of a transport path unit included in the transport system according to the first embodiment.

[0013] Figure 3 This is a diagram for explaining the regeneration control executed by the transportation system according to the first embodiment.

[0014] Figure 4 This is a diagram for explaining the operation of each transport path unit included in the transport system according to the first embodiment.

[0015] Figure 5 This is a diagram showing a configuration example of a transport system according to the second embodiment.

[0016] Figure 6 This is a diagram for explaining the operation of each transport path unit included in the transport system according to the second embodiment.

[0017] Figure 7 This is a diagram showing a configuration example of a transport path unit according to a modification of the second embodiment.

[0018] Figure 8 This is a diagram showing a configuration example of a controller included in the transportation system according to the third embodiment.

[0019] Fig. 9 This is a diagram showing a configuration example of a learning device included in a controller according to a third embodiment.

[0020] Fig.10 This is a flowchart showing the processing procedure of the learning device included in the controller according to the third embodiment.

[0021] Fig.11 This is a diagram showing a configuration example of a position command generating unit included in a controller according to a third embodiment.

[0022] Fig.12 This is a flowchart showing the processing procedure of the position command generating unit and the coil drive command generating unit included in the controller according to the third embodiment.

[0023] Fig.13 This is a diagram showing a configuration example of a control circuit according to the first to third embodiments.

[0024] Fig.14 This is a diagram showing a configuration example of a dedicated hardware circuit according to the first to third embodiments. DETAILED DESCRIPTION

[0025] Hereinafter, the transportation system according to the embodiment will be described in detail with reference to the drawings.

[0026] Implementation method 1.

[0027] Figure 1 1 is a diagram showing a configuration example of a conveyance system 1 according to Embodiment 1. The conveyance system 1 is a system used for conveying an object. In Embodiment 1, the conveyance system 1 conveys the object by moving a conveyance body on which the object is placed.

[0028] The conveying system 1 includes a plurality of conveying path units 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, a controller 12, a direct current (DC) power supply 13, and carriages 16A, 16B, 16C. In the following description, the conveying path units 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H are referred to as conveying path units 11 without distinguishing each other.

[0029] The plurality of conveying path units 11 are connected to each other to form a conveying path 10 for the conveying body to move. The plurality of conveying path units 11 move the conveying body by applying power to the conveying body. The trolleys 16A, 16B, and 16C are each a conveying body. In the following description, the trolleys 16A, 16B, and 16C are referred to as trolleys 16 without distinguishing each other.

[0030] Figure 1 The conveying path 10 shown is annular. Figure 1 The transport path 10 shown is a closed path. The transport path 10 of the transport system 1 may also be an open path. That is, the transport path 10 of the transport system 1 may be a path having a start point and an end point.

[0031] The conveying path units 11A, 11B, 11E, and 11F are straight-line conveying path units 11 constituting a straight path. The conveying path units 11C, 11D, 11G, and 11H are curved-line conveying path units 11 constituting a curved path, and change the traveling direction of the conveyor. The conveying path 10 may not have the conveying path units 11 constituting a straight path, but may be constituted only by the conveying path units 11 constituting a curved path. The overall shape of the conveying path 10 is arbitrary.

[0032] The trolley 16 is installed on the side of the conveying path 10. The trolley 16 moves along the guide rail provided on the side of the conveying path 10. The trolley 16 moves on the side of the conveying path 10 and stops on the side of the conveying path 10. The conveying system 1 involved in Embodiment 1 is a moving magnet type linear motor. The trolley 16 can move along the guide rail provided on the upper surface of the conveying path 10. The trolley 16 has a permanent magnet constituting a movable part, a permanent magnet for a linear scale, and a guide roller that moves on the guide rail by rotating. Figure 1 In the figure, the guide rail, the guide roller, the permanent magnet constituting the movable part, and the permanent magnet for the linear scale are omitted.

[0033] exist Figure 1 In the example shown, the conveying system 1 has 8 conveying path units 11 and 3 carriages 16. The number of conveying path units 11 that the conveying system 1 has is arbitrary. That is, the number of conveying path units 11 that constitute the conveying path 10 is arbitrary. The conveying system 1 only needs to have a plurality of conveying path units 11. The number of carriages 16 that move in the conveying path 10 is arbitrary. The conveying system 1 only needs to have one or more carriages 16.

[0034] The conveying system 1 is not limited to a system having a linear motor, and may be a system having a rotary motor. The conveying system 1 may be a belt conveyor having a rotary motor and a conveyor belt rotated by the rotary motor. The belt conveyor moves the workpiece placed on the conveyor belt. The conveying system 1 may be a roller conveyor having a plurality of rollers and a rotary motor that rotates the rollers. The roller conveyor moves the workpiece placed on the rollers.

[0035] The DC power supply 13 is connected to each transport path unit 11 via a DC power supply bus 15. The DC power supply 13 is a power supply device or a power supply circuit that outputs a direct current voltage. The DC power supply 13 supplies power to each transport path unit 11. Each transport path unit 11 shares the DC power supply 13.

[0036] A DC bus on the positive side and a DC bus on the negative side pass through the DC power bus 15. The DC bus on the positive side is called a P bus. The DC bus on the negative side is called an N bus. The P bus is connected to the positive pole of the DC power supply 13. The N bus is connected to the negative pole of the DC power supply 13. Hereinafter, when referring to both the P bus and the N bus, they are referred to as a PN bus. The plurality of transport path units 11 constituting the transport path 10 are each connected to a common DC bus.

[0037] The conveying system 1 has a structure in which each conveying path unit 11 is connected to the DC power supply 13 by multi-point connection. The connection method between each conveying path unit 11 and the DC power supply 13 is not limited to multi-point connection, and may also be a daisy chain connection. Figure 1 In the example shown, the transport system 1 includes one DC power supply 13 , but the transport system 1 may include a plurality of DC power supplies 13 . That is, a plurality of power supply domains may be configured in the transport system 1 .

[0038] The controller 12 is connected to each conveying path unit 11 via a data communication line 14. The controller 12 controls each of the plurality of conveying path units 11. The data communication line 14 is composed of a line connecting the controller 12 and one of the plurality of conveying path units 11, namely, the conveying path unit 11A, and a line connecting adjacent conveying path units 11. The conveying system 1 has a structure in which each conveying path unit 11 is connected to the controller 12 via a daisy chain connection. The connection method of each conveying path unit 11 and the controller 12 is not limited to a daisy chain connection. The connection method of each conveying path unit 11 and the controller 12 may also be a star connection in which each conveying path unit 11 is connected to the controller 12 via a communication hub. Alternatively, the conveying system 1 may also have a plurality of data communication lines 14, and each conveying path unit 11 and the controller 12 are directly connected via the data communication lines 14.

[0039] The controller 12 generates a position instruction indicating the position to which the carriage 16 is to be moved, and generates a coil drive instruction based on the position instruction. The controller 12 outputs the coil drive instruction to each conveying path unit 11. Each conveying path unit 11 drives the coil of the conveying path unit 11 according to the coil drive instruction. The controller 12 outputs the coil drive instruction to each conveying path unit 11, thereby controlling the movement of each carriage 16. In addition, the coil drive instruction is, for example, a current instruction, a speed instruction, or a thrust instruction.

[0040] The traveling direction of each vehicle 16 is Figure 1 In the clockwise direction, or Figure 1 The counterclockwise direction in the direction of travel. Figure 1 Set the clockwise direction in the moving direction as the positive direction. Figure 1The counterclockwise direction in is set as the reverse direction. Arrow 17A indicates the positive direction. Arrow 17B indicates the reverse direction.

[0041] A control device higher than the controller 12, such as a programmable logic controller, may be connected to the controller 12. The control device outputs instructions for sequence control to the controller 12. A human-machine interface may be connected to the controller 12. The human-machine interface receives input from an operator. In addition, the human-machine interface outputs information indicating the status of the conveying system 1 through a display or the like. The controller 12 may obtain operation information of the trolley 16 from a higher-level control device or human-machine interface, and generate a position instruction based on the operation information. The operation information is information indicating the scheduling related to the movement of each of the plurality of trolleys 16 in the conveying path 10.

[0042] Next, the structure of the transport path unit 11 will be described. Here, the structure of the transport path unit 11 will be described by taking the linear transport path unit 11 as an example. In the curved transport path unit 11, the arrangement of the coils is different from that of the linear transport path unit 11. The structure of the curved transport path unit 11 is the same as that of the linear transport path unit 11 except that the arrangement of the coils is different.

[0043] Figure 2 FIG. 1 is a diagram showing a configuration example of a transport path unit 11 included in the transport system 1 according to the first embodiment. Figure 2 2 shows permanent magnets 40 and 41 included in the transport path unit 11 and the carriage 16. The permanent magnet 40 is a permanent magnet constituting a movable element, and the permanent magnet 41 is a permanent magnet for a linear scale.

[0044] The conveying path unit 11 has a plurality of coils 20. Each coil 20 functions as a driving unit that generates power by being supplied with power from the PN bus. Figure 2 In the example shown, the conveying path unit 11 has nine coils 20. The number of coils 20 provided in the conveying path unit 11 is arbitrary. In a linear conveying path unit 11, a plurality of coils 20 are arranged in a linear direction. In addition, in a curved conveying path unit 11, a plurality of coils 20 are arranged in a curved direction.

[0045] An inverter circuit 21 is connected to each coil 20 of the transmission path unit 11. The inverter circuit 21 has a switching element, and supplies the electric power after the electric power conversion performed by turning on and off the switching element to the coil 20. The illustration of the switching element is omitted. The inverter circuit 21 controls the 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 be a three-phase inverter circuit connected to three coils 20. Each coil 20 of the transmission path unit 11 contains not only a pure inductance component but also a coil resistance.

[0046] Each inverter circuit 21 of the transmission path unit 11 is connected between the P bus 31 which is the positive wiring of the DC power bus 15 and the N bus 32 which is the negative wiring of the DC power bus 15. Each inverter circuit 21 converts the DC power from the PN bus into AC power and supplies the AC power to the coil 20. The inverter circuit 21 performs power conversion from DC power to AC power by turning on and off the switching element.

[0047] The coil 20 is supplied with electric power converted by the inverter circuit 21, thereby generating an electromagnetic force that becomes the power to move the carriage 16. A current sensor 22 is connected to each coil 20 of the conveying path unit 11. The current sensor 22 detects the current value of the current flowing in the coil 20, that is, the actual current value of the coil. In addition, in the conveying path unit 11, a capacitor 23 as an electrolytic capacitor is connected between the P bus 31 and the N bus 32.

[0048] The inverter circuit 21 is connected to a current controller 24 for controlling the inverter circuit 21. The current controller 24 calculates the voltage value of the voltage applied to the coil 20 based on the current command value of the current flowing through the coil 20 and the actual current value of the coil detected by the current sensor 22. The current controller 24 sends a pulse width modulation (PWM) signal obtained by comparing the calculated voltage value with the triangular wave to the inverter circuit 21. The current controller 24 sends the PWM signal to the inverter circuit 21, thereby turning the inverter circuit 21 on and off. As a result, the current controller 24 applies a voltage to the coil 20 for causing a current of a desired current value to flow through the coil 20. The current controller 24 can perform PID (Proportional Integral Differential) control of the voltage applied to the coil 20 based on the deviation between the current command value and the actual current value of the coil, thereby calculating the voltage value of the voltage applied to the coil 20.

[0049] The transmission path unit 11 includes a linear scale 25, a processor 27, and a bus voltage detection unit 33. The bus voltage detection unit 33 detects the bus voltage. The bus voltage is the voltage of the PN bus as a DC bus, that is, the voltage between the P bus 31 and the N bus 32. The bus voltage detection unit 33 outputs the detection result of the bus voltage to the processor 27.

[0050] The linear scale 25 is a detection unit that detects the position of the carriage 16 on the conveying path unit 11. A plurality of conveying path units 11 are connected to each other to form the conveying path 10, and thus the linear scale 25 is provided on the conveying path 10. The processor 27 is a CPU (Central Processing Unit). The processor 27 may be an arithmetic device, a processing device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor).

[0051] The linear scale 25 has a plurality 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 the magnetic field of the permanent magnet 40 or the magnetic field of the permanent magnet 41. Here, the position sensor 26 is a Hall sensor equipped with two Hall elements. The interval between the two Hall elements is an interval equivalent to half the magnetic pole spacing 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 trolley 16. The waveform of the electrical signal output by one Hall element becomes a sin wave. The waveform of the electrical signal output by another Hall element becomes a cos wave.

[0052] The AD (Analog to Digital) converter of the processor 27 detects the sin wave and the cos wave. The processor 27 calculates arctan based on the information of the sin wave and the cos wave, thereby detecting the position of the carriage 16 relative to the position sensor 26. Thus, the processor 27 obtains position information indicating the position of the carriage 16.

[0053] In addition, the processor 27 obtains the detection result of the bus voltage from the bus voltage detection unit 33. The processor 27 controls the start of the regenerative power supply by the inverter circuit 21 and the stop of the regenerative power supply by the inverter circuit 21. The regenerative power supply will be described later.

[0054] The conveying path unit 11 has a communication slave station 28. The communication slave station 28 is a communication slave station on the conveying path unit 11 side. The data communication line 14 is connected to the communication slave station 28. When each conveying path unit 11 and the controller 12 are connected by a daisy chain connection, the communication slave station 28 is configured to be able to connect two data communication lines 14. The communication slave station 28 receives current instructions representing current instruction values ​​of currents flowing through the coils 20 from the controller 12 for each of the plurality of coils 20 provided in the conveying path unit 11. The communication slave station 28 obtains position information obtained by the processor 27 based on the outputs of each of the plurality of position sensors 26 provided in the linear scale 25. The communication slave station 28 sends the obtained position information to the controller 12.

[0055] The communication slave station 28 performs, for example, periodic communication to receive a current command and transmit position information in a constant cycle. The communication slave station 28 may receive a current command and transmit position information aperiodically instead of the periodic communication.

[0056] As described above, the transport path unit 11 mainly has the function of controlling the energization of the coil 20 and the function of acquiring position information. All of the plurality of transport path units 11 constituting the transport path 10 similarly control the energization of the coil 20 and similarly acquire position information.

[0057] Next, the operation of the transmission system 1 by sharing the PN bus will be described. Figure 1 In the transport path unit 11 shown in FIG. 1 , the trolley 16A and the trolley 16B are set to be in a power running state, for example, a state of accelerating. Figure 1 In the transport path unit 11 shown, the trolley 16C is set to be in a regeneration state, for example, a deceleration state. In this state, when the regenerative power of the trolley 16C is less than the sum of the power running power of the trolley 16A and the power running power of the trolley 16B, the regenerative power is consumed as the power running power, thereby preventing the bus voltage from rising due to the generation of the regenerative power.

[0058] In contrast, when all of the trolleys 16A, 16B, and 16C are in the regeneration state, the regenerative power generated by each of the trolleys 16A, 16B, and 16C is not consumed, so the bus voltage rises. Alternatively, when the trolleys 16A, 16B, and 16C include the trolleys 16 in the power running state and the trolleys 16 in the regeneration state, and the regenerative power generated by the trolleys 16 in the regeneration state is greater than the power running power consumed by the trolleys 16 in the power running state, the bus voltage also rises. If the bus voltage rises excessively, it will have an adverse effect on the life of the capacitor 23, or cause the capacitor 23 to be damaged. Therefore, the transport system 1 involved in the first embodiment performs regeneration control that consumes the regenerative power in a plurality of transport path units 11 as described below.

[0059] Here, the regeneration control performed by the transport system 1 is described. In the transport system 1, one or more than two transport path units 11 among the plurality of transport path units 11 into which the trolley 16 has not entered performs regeneration power supply of the regenerative power generated by the plurality of transport path units 11 to the coil 20. When the bus voltage is greater than or equal to a preset first voltage threshold, one or more than two transport path units 11 among the plurality of transport path units 11 into which the trolley 16 has not entered performs regeneration power supply. The first voltage threshold is a value of the bus voltage that serves as a reference for starting the regeneration control. The first voltage threshold is preset in each transport path unit 11 of the transport system 1.

[0060] In addition, the transmission path unit 11 that performs regenerative power supply stops the regenerative power supply when the bus voltage is less than or equal to the second voltage threshold. The second voltage threshold is a value of the bus voltage that serves as a reference for stopping the regenerative control. The second voltage threshold is preset in each transmission path unit 11 of the transmission system 1. In addition, the transmission path unit 11 that enters the trolley 16 while performing regenerative power supply stops the regenerative power supply. As described above, the transmission path unit 11 stops the regenerative power supply when the bus voltage is less than or equal to the second voltage threshold, or when the trolley 16 enters the transmission path unit 11.

[0061] Here, in Figure 1 In the conveying path unit 11 shown, the case where the carriage 16A starts to decelerate when the carriages 16B and 16C stop is taken as an example. The carriage 16B stops by crossing the conveying path unit 11C and the conveying path unit 11D. The carriage 16C stops by crossing the conveying path unit 11E and the conveying path unit 11F. The carriage 16A starts to decelerate in the conveying path unit 11A.

[0062] Figure 3 1 is a diagram for explaining the regeneration control performed by the transport system 1 according to the first embodiment. Figure 3 , a timing chart of the speed of the carriage 16 on the conveying path unit 11 in the regenerative state, the bus voltage Vpn, the regenerative power W1, and the regenerative power W2 is shown. The regenerative power W1 is assumed to be the regenerative power supplied to the coil 20 of the conveying path unit 11 where the carriage 16 does not exist. The regenerative power W2 is assumed to be the regenerative power supplied to the coil 20 of the conveying path unit 11 where the carriage 16 exists. Figure 3 The speed of the carriage 16 shown is assumed to be the speed of the carriage 16A. The conveyance path units 11 having the carriage 16 are the conveyance path units 11A, 11C, 11D, 11E, and 11F. The conveyance path units 11 not having the carriage 16 are the conveyance path units 11B, 11G, and 11H.

[0063] The voltage value Von is set to the first voltage threshold. The voltage value Voff is set to the second voltage threshold. Here, the voltage value Von set in each transport path unit 11 of the transport system 1 is set to be the same. The voltage value Voff set in each transport path unit 11 of the transport system 1 is set to be the same.

[0064] When the vehicle 16A starts to decelerate at time t1, regenerative power is generated in the coil 20 of the transmission path unit 11A. As the regenerative power is generated in the coil 20 of the transmission path unit 11A, the bus voltage Vpn starts to rise from time t1. The processor 27 of each transmission path unit 11 always monitors the detection result of the bus voltage Vpn obtained by the bus voltage detection unit 33.

[0065] like Figure 3 As shown, it is assumed that the bus voltage Vpn reaches the voltage value Von at time t2. The processor 27 of each conveying path unit 11B, 11G, 11H without the carriage 16 starts the regenerative power supply through the inverter circuit 21. The regenerative power W1 supplied to the coil 20 of each conveying path unit 11B, 11G, 11H starts to rise from zero at time t2.

[0066] When the inverter circuit 21 performs regenerative power supply, the current controller 24 performs current control so that a current equivalent 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 coil 20 converts the current into heat, and thus the regenerative power W1 is consumed by the coil 20.

[0067] The regenerative power W1 is consumed, and thus the bus voltage Vpn gradually decreases from the voltage value Von. Figure 3As shown in FIG. 1 , it is assumed that the bus voltage Vpn decreases from the voltage value Von at time t2 and reaches the voltage value Voff at time t3. The processor 27 of each transmission path unit 11B, 11G, 11H stops the regenerative power supply by the inverter circuit 21. Figure 3 In the example shown, the regenerative power W1 starts to increase from time t2 and then maintains a constant value, and starts to decrease from time t3. Then, the regenerative power W1 becomes zero.

[0068] In each of the transport path units 11A, 11C, 11D, 11E, and 11F where the carriage 16 is present, the carriage 16 is moved and stopped. Figure 3 In the illustrated time series, the regenerative power W2 supplied to the coils 20 of the respective transmission path units 11A, 11C, 11D, 11E, and 11F is kept at zero.

[0069] Figure 4 1 is a diagram for explaining the operation of each transport path unit 11 included in the transport system 1 according to the first embodiment. Figure 4 In FIG. 1 , a table is shown that summarizes the presence or absence of the cart 16 of each transport path unit 11 and the availability of regenerative power supply of each transport path unit 11 in the above example. Figure 4 In the figure, "A", "B", ..., and "H" shown in the "transmission path unit" column represent the transmission path unit 11A, the transmission path unit 11B, ..., and the transmission path unit 11H, respectively. "Yes" shown in the "regenerative power supply" column indicates that regenerative power supply is performed. "No" shown in the "regenerative power supply" column indicates that regenerative power supply is not performed.

[0070] If the processor 27 of the transport path unit 11 does not detect the carriage 16 through the linear scale 25, it is determined that the carriage 16 has not entered the transport path unit 11. If the processor 27 detects the carriage 16 through the linear scale 25, it is determined that the carriage 16 has entered the transport path unit 11. Figure 4 As shown, each of the transport path units 11B, 11G, and 11H into which the vehicle 16 has not entered performs regenerative power supply. Each of the transport path units 11A, 11C, 11D, 11E, and 11F into which the vehicle 16 has entered does not perform regenerative power supply.

[0071] The transport system 1 prevents the bus voltage Vpn from excessively increasing by exceeding the voltage value Von by executing the regenerative power supply in the transport path unit 11 where the trolley 16 has not entered. The transport system 1 stops the regenerative power supply to each transport path unit 11 until the bus voltage Vpn decreases to the voltage value Voff in the transport path unit 11 that executes the regenerative power supply. The transport system 1 consumes the regenerative power generated in the plurality of transport path units 11 by the regenerative control as described above. The transport system 1 can prevent the bus voltage Vpn from excessively increasing.

[0072] In the above description, the voltage value Von set in each transport path unit 11 of the transport system 1 is set to be the same, but the plurality of transport path units 11 may include transport path units 11 each having a different voltage value Von set. Any voltage value Von can be set individually in each of the plurality of transport path units 11.

[0073] In the above description, the voltage value Voff set in each transport path unit 11 of the transport system 1 is set to be the same, but the plurality of transport path units 11 may include transport path units 11 each having a different voltage value Voff set. Any voltage value Voff can be set individually in each of the plurality of transport path units 11.

[0074] As described above, in the transmission system 1, at least one of the first voltage threshold and the second voltage threshold can be set individually in each of the plurality of transmission path units 11. The transmission system 1 can arbitrarily set at least one of the first voltage threshold and the second voltage threshold according to the manner in which the regenerative power supply is desired to be achieved by the transmission path unit 11.

[0075] The number of phases of the coil 20, the resistance value of the coil 20, or the size of the housing of the transport path unit 11 are different between the linear transport path unit 11 and the curved transport path unit 11. Therefore, for example, at least one of the first voltage threshold and the second voltage threshold can be set to different values ​​between the linear transport path unit 11 and the curved transport path unit 11. At least one of the first voltage threshold and the second voltage threshold is set individually in each of the plurality of transport path units 11, so that the transport system 1 can achieve regenerative power consumption suitable for the structure of each transport path unit 11.

[0076] In the transmission path unit 11 having a large number of coil 20 phases, the first voltage threshold can be lowered compared to the transmission path unit 11 having a small number of coil 20 phases. Thus, the transmission system 1 can make the transmission path unit 11 having a large number of coil 20 phases preferentially perform regenerative power supply. In addition, the number of phases of the coil 20 can be said to be the number of coils 20 provided in one transmission path unit 11. Figure 2 2 , the conveying path unit 11 in which the number of phases of the coil 20 is nine is illustrated.

[0077] In each transmission path unit 11 of the transmission system 1, a power threshold value of the upper limit of the regenerative power W1 allowed to be supplied to the coil 20 is preset. Here, the power threshold value set in each transmission path unit 11 of the transmission system 1 is set to be the same. When regenerative power supply is executed, the transmission path unit 11 whose power supplied to the coil 20 exceeds the preset power threshold value stops the regenerative power supply. The rated current of the coil 20 is set to I rate , the coil resistance of coil 20 is R coil , for example, I rate 2 ×R coil The power threshold value is set. A value obtained based on the electronic overheat protection curve of each coil 20 may also be set as the power threshold value. The power threshold value is not limited to these values ​​and can be set to any value. The transmission system 1 stops the supply of regenerative power in the transmission path unit 11 when the power supplied to the coil 20 exceeds the power threshold value, thereby preventing the situation where the regenerative power is not consumed due to overheating of the coil 20.

[0078] In the above description, the power thresholds set in the respective transport path units 11 of the transport system 1 are all set to be the same, but the plurality of transport path units 11 may include transport path units 11 each having a different power threshold set. An arbitrary power threshold can be set individually in each of the plurality of transport path units 11. The transport system 1 can arbitrarily set the power threshold in accordance with the manner of regenerative power supply desired to be achieved by the transport path unit 11. For example, the power thresholds can be set to different values ​​in a linear transport path unit 11 and a curved transport path unit 11. By setting the power thresholds individually in each of the plurality of transport path units 11, the transport system 1 can achieve regenerative power consumption suitable for the structure of each transport path unit 11.

[0079] In addition, in the conveying system 1, for example Figure 1The trolley 16A shown is set to move from the conveying path unit 11A to the conveying path unit 11H during deceleration. If the entire trolley 16A enters the conveying path unit 11H and the trolley 16A does not exist in the conveying path unit 11A, the conveying path unit 11A starts to supply regenerative power. Alternatively, if the trolley 16A starts to enter the conveying path unit 11H, the conveying path unit 11H that does not exist in the trolley 16 stops supplying regenerative power until the trolley 16A enters. As described above, the conveying path units 11A and 11H switch between executing and stopping the regenerative power supply as the trolley 16A moves. The conveying path units 11 other than the conveying path units 11A and 11H also switch between executing and stopping the regenerative power supply as the trolleys 16B and 16C move. The transport system 1 switches the transport path unit 11 that supplies regenerative power as the vehicle 16 moves, thereby consuming the regenerative power generated in the plurality of transport path units 11 while continuing the movement of the vehicle 16 .

[0080] The inverter circuit 21 operates at a lower on-off frequency when supplying regenerative power than when supplying power to the vehicle 16. In other words, the inverter circuit 21 operates at a lower on-off frequency when switching the switch of the inverter circuit 21 when supplying regenerative power than when supplying power to the vehicle 16. Thus, the transmission path unit 11 can reduce noise caused by switching the inverter circuit 21 when supplying regenerative power.

[0081] According to Embodiment 1, in the transport system 1, one or more than two transport path units 11, among the plurality of transport path units 11, into which the transport body does not enter, perform regenerative power supply. In the transport system 1, even if the point at which the transport body decelerates is uncertain, regenerative power can be consumed. Thus, the transport system 1 has the effect of being able to appropriately handle regenerative power.

[0082] Implementation method 2.

[0083] In the second embodiment, an example is described in which a conveying path unit 11 adjacent to a conveying path unit 11 in which a trolley 16 is present is excluded from the conveying path unit 11 that performs regenerative power supply. In the second embodiment, when a trolley 16 moving in a certain conveying path unit 11 enters its adjacent conveying path unit 11 during the communication cycle, the trolley 16 can be smoothly moved. The communication cycle is assumed to be a cycle of communication between the controller 12 and the conveying path unit 11. In the second embodiment, the same reference numerals are given to the same structural elements as those in the first embodiment, and the structure different from the first embodiment is mainly described.

[0084] Figure 5 1 is a diagram showing a configuration example of a conveying system 2 according to Embodiment 2. In the conveying system 2, the processing performed by the controller 12 is different from that in Embodiment 1. Figure 1 The structure of the conveying system 1 shown is the same as that of the conveying system 1. The conveying path unit 11 has Figure 2 The structure is the same as the structure shown.

[0085] exist Figure 5 In the example shown, the conveying system 2 has eight conveying path units 11 and two carts 16. The number of conveying path units 11 that the conveying system 2 has is arbitrary. That is, the number of conveying path units 11 that constitute the conveying path 10 is arbitrary. The conveying system 2 only needs to have a plurality of conveying path units 11. The number of carts 16 that move in the conveying path 10 is arbitrary. The conveying system 2 only needs to have one or more carts 16.

[0086] The communication slave station 28 of the transport path unit 11 acquires the position information acquired by the processor 27 based on the outputs from each of the plurality of position sensors 26 included in the linear scale 25. The communication slave station 28 transmits the acquired position information to the controller 12 via the data communication line 14.

[0087] The controller 12 receives the position information transmitted from the communication slave station 28 of each conveying path unit 11. The controller 12 synthesizes the position information from the communication slave station 28 of each conveying path unit 11, thereby obtaining the position information indicating the position of the vehicle 16 in the conveying path 10. Based on the position information indicating the position of the vehicle 16 in the conveying path 10, the controller 12 determines the conveying path unit 11 to execute the regenerative power supply and the conveying path unit 11 to stop the regenerative power supply.

[0088] The controller 12 excludes the first conveying path unit and the second conveying path unit from among the plurality of conveying path units 11 from the conveying path units 11 that perform regenerative power supply. The controller 12 determines the conveying path units 11 other than the first conveying path unit and the second conveying path unit from among the plurality of conveying path units 11 as the conveying path units 11 that perform regenerative power supply. The first conveying path unit is a conveying path unit 11 having a carriage 16 as a conveying body. The second conveying path unit is M conveying path units 11 located adjacent to the first conveying path unit in the first direction along the conveying path 10 and N conveying path units 11 located adjacent to the first conveying path unit in the second direction. The second direction is a direction along the conveying path 10 and opposite to the first direction. The first direction is set to be a positive direction indicated by an arrow 17A. The second direction is set to be a reverse direction indicated by an arrow 17B. M and N are each set to be an arbitrary integer greater than or equal to 1. In the second embodiment, at least one of one or two or more transport path units 11 in the transport path 10 into which the vehicle 16 does not enter performs regenerative power supply.

[0089] Next, the operation of the transmission system 2 when the regenerative power supply is executed will be described. Figure 5 The operation of each transport path unit 11 will be described by taking the state shown in FIG. Figure 5 In the state shown, the dolly 16A exists in the conveyance path unit 11A. In addition, the dolly 16B exists astride the conveyance path unit 11C and the conveyance path unit 11D.

[0090] Figure 6 1 is a diagram for explaining the operation of each transport path unit 11 included in the transport system 2 according to Embodiment 2. The controller 12 identifies the first transport path unit based on the acquired position information. Figure 5 In the illustrated example, the transport path unit 11A including the carriage 16A and the transport path units 11C and 11D including the carriage 16B are first transport path units.

[0091] Next, the controller 12 identifies the second transport path unit based on the identified first transport path unit. Here, it is assumed that M=1 and N=1. Figure 5In the example shown, each of the transport path units 11B, 11E, and 11H is a second transport path unit. The controller 12 excludes each of the transport path units 11A, 11C, and 11D as the first transport path unit and each of the transport path units 11B, 11E, and 11H as the second transport path unit from the transport path unit 11 that performs regenerative power supply. The controller 12 sends a stop instruction for regenerative power supply to each of the transport path units 11A, 11B, 11C, 11D, 11E, and 11H. The stop instruction for regenerative power supply is, for example, a signal that a flag indicating execution of regenerative power supply is set to off.

[0092] Next, the controller 12 identifies the transport path units 11 other than the first transport path unit and the second transport path unit among the plurality of transport path units 11 included in the transport system 2. Figure 5 In the example shown, each of the transport path units 11F and 11G is a transport path unit 11 other than the first transport path unit and the second transport path unit. The controller 12 determines each of the transport path units 11F and 11G as a transport path unit 11 that performs regenerative power supply. The controller 12 sends an execution instruction of regenerative power supply to each of the transport path units 11F and 11G. The execution instruction of regenerative power supply is, for example, a signal that a flag indicating execution of regenerative power supply is set to on.

[0093] The communication slave station 28 of each conveying path unit 11A, 11B, 11C, 11D, 11E, 11H receives the regenerative power supply stop instruction sent from the controller 12. Each conveying path unit 11A, 11B, 11C, 11D, 11E, 11H is set to a state where regenerative power supply is not performed according to the regenerative power supply stop instruction. Each conveying path unit 11A, 11B, 11C, 11D, 11E, 11H performs a normal operation for providing power to the carriage 16.

[0094] The communication slave station 28 of each transmission path unit 11F, 11G receives the execution instruction of the regenerative power supply transmitted from the controller 12. Each transmission path unit 11F, 11G executes the regenerative power supply in accordance with the execution instruction of the regenerative power supply.

[0095] The number M of the second conveying path units located adjacent to the first conveying path unit in the first direction and the number N of the second conveying path units located adjacent to the first conveying path unit in the second direction are preset. At least one of M and N can be calculated based on the speed of the carriage 16 in the conveying path 10.

[0096] Here, an example of a method of calculating M and N based on the speed of the carriage 16 in the conveying path 10 is described. Here, the path length of the conveying path unit 11 is set to L, the maximum speed of the carriage 16 is set to Vmax, and the communication cycle of the communication between the controller 12 and the conveying path unit 11 is set to Tcyc. M and N are each obtained by rounding down the decimal point of L / (Vmax×Tcyc).

[0097] As described above, in the second embodiment, the transport system 2 excludes not only the first transport path unit where the trolley 16 exists, but also the second transport path unit adjacent to the first transport path unit from the transport path unit 11 that performs regenerative power supply. When the trolley 16 moving in the first transport path unit enters the second transport path unit adjacent thereto, the trolley 16 enters the second transport path unit that performs the normal operation for providing power to the trolley 16. As a result, the transport system 2 eliminates the situation where the trolley 16 enters the transport path unit 11 that performs regenerative power supply during the communication cycle, and thus the trolley 16 can be smoothly moved in the portion where the transport path units 11 are adjacent to each other.

[0098] In the above description, M and N are arbitrary integers greater than or equal to 1, but at least one of M and N may be zero. That is, the second conveying path unit only needs to be at least one of one or more than two conveying path units 11 located adjacent to the first conveying path unit in the first direction and one or more than two conveying path units 11 located adjacent to the first conveying path unit in the second direction. The conveying system 2 may switch one of M and N to zero and an integer greater than or equal to 1 for each communication cycle based on the travel direction of the carriage 16 for each communication cycle.

[0099] The controller 12 can exclude, from the plurality of conveying path units 11, the conveying path unit 11 in which the conveying body exists, that is, the first conveying path unit, and one or more than two conveying path units 11 located adjacent to the first conveying path unit in the traveling direction of the conveying body in the conveying path 10, that is, the second conveying path unit, from the conveying path units 11 that perform the regenerative power supply. The second conveying path unit located adjacent to the first conveying path unit in front of the traveling direction performs the normal operation for giving power to the trolley 16. The conveying system 2 can smoothly move the trolley 16 in the portion where the conveying path units 11 are adjacent to each other. In this case, the number of the second conveying path units can also be calculated based on the speed of the trolley 16 in the conveying path 10.

[0100] According to the second embodiment, the transport system 2 excludes the first transport path unit and the second transport path unit from the transport path unit 11 that performs regenerative power supply, thereby performing a normal operation for providing power to the trolley 16 in the first transport path unit and the second transport path unit. Thus, the transport system 2 can smoothly move the trolley 16. In addition, the transport system 2 performs regenerative power supply in the transport path unit 11 other than the first transport path unit and the second transport path unit among the plurality of transport path units 11. Thus, the transport system 2 can appropriately handle the regenerative power.

[0101] Figure 7 1 is a diagram showing a configuration example of a transport path unit 11 according to a modification of Embodiment 2. The transport path unit 11 according to the modification of Embodiment 2 includes a temperature sensor 34. The controller 12 determines the transport path unit 11 to perform regenerative power supply based on the temperature detection results obtained by the temperature sensors 34 of each of the plurality of transport path units 11.

[0102] In the transmission path unit 11 that performs regenerative power supply, the temperature inside the transmission path unit 11 increases due to the consumption of regenerative power in the coil 20. The controller 12 compares the temperatures of the transmission path units 11 of the transmission system 2. The controller 12 determines one or more than two transmission path units 11 in order of temperature from low to high among the plurality of transmission path units 11 as the transmission path unit 11 that performs regenerative power supply. Thus, the transmission system 2 can make the temperature of each transmission path unit 11 uniform. By making the temperature of each transmission path unit 11 uniform, it is possible to extend the life of the components in the transmission path unit 11 that deteriorate due to the influence of temperature. In addition, the controller 12 can predetermine a temperature threshold value to be compared with the temperature detection results obtained by the temperature sensors 34 of each of the plurality of transmission path units 11, and determine one or more than two transmission path units 11 whose temperature detection results obtained by the temperature sensors 34 are less than or equal to the temperature threshold value as the transmission path unit 11 that performs regenerative power supply.

[0103] Implementation method 3.

[0104] In Embodiment 3, an example is described in which machine learning is applied when the controller 12 generates position instructions to be output to each transport path unit 11. The controller 12 generates position instructions such that the number of transport path units 11 that perform regenerative power supply increases based on the trained model according to the operation information of each vehicle 16.

[0105] For example, assume that operation information indicating that the trolley 16 reaches the target position 3 meters ahead from the current position 2 seconds after a certain moment is obtained. In this case, all modes can be obtained as the mode of the position instruction to move the trolley 16. One of the modes that can be obtained is a mode in which the trolley 16 is moved by trapezoidal acceleration and deceleration from the starting point to the end point in the 2 seconds. As other modes, there is a mode in which the trolley 16 is moved by trapezoidal acceleration and deceleration for 1 second from the starting point and the trolley 16 is stopped for the remaining 1 second, or a mode in which the trolley 16 is stopped for 1 second from the starting point and the trolley 16 is moved by trapezoidal acceleration and deceleration for the remaining 1 second, etc. There are countless modes that can be obtained as the mode of the position instruction.

[0106] The transport system 2 sets a pattern of position instructions for each vehicle 16, thereby increasing the number of transport path units 11 that perform regenerative power supply for each control cycle. That is, if the transport system 2 can increase the number of transport path units 11 that perform regenerative power supply, the regenerative power consumed in one transport path unit 11 can be reduced, and an excessive temperature rise of the transport path unit 11 can be prevented. In the third embodiment, the position instruction for increasing the number of transport path units 11 that perform regenerative power supply is derived by a machine learning method.

[0107] The structure of the conveying system 2 according to the third embodiment is as follows: Figure 5 The structure of the conveying system 2 shown is the same. The controller 12 of the conveying system 2 involved in the third embodiment obtains the position information indicating the position of the carriage 16 in the conveying path 10 in the same manner as in the second embodiment. The third embodiment is different from the second embodiment in that a structural element for machine learning is added to the controller 12.

[0108] Figure 8 1 is a diagram showing a configuration example of the controller 12 included in the transport system 2 according to Embodiment 3. The controller 12 includes a learning device 51 , a trained model storage unit 52 , a position command generation unit 53 , and a coil drive command generation unit 54 .

[0109] The learning device 51 learns the relationship between the operation information of each of the plurality of trolleys 16 in the transport system 2 and the position command such that the number of transport path units 11 that perform regenerative power supply increases. The operation information is information indicating the schedule related to the movement of each of the plurality of trolleys 16 in the transport path 10. The position command indicates the position to which the trolley 16 is to be moved. The learning device 51 outputs a trained model as a result of the learning. The trained model storage unit 52 stores the trained model.

[0110] The position command generation unit 53 generates a position command indicating a position to be moved to each of the plurality of vehicles 16 included in the transport system 2. The position command generation unit 53 reads the trained model from the trained model storage unit 52. The position command generation unit 53 inputs the operation information to the trained model, thereby inferring the position command for an increase in the number of transport path units 11 that perform regenerative power supply. The position command generation unit 53 generates the position command through the inference.

[0111] The coil drive command generation unit 54 generates a coil drive command based on the position command. The controller 12 outputs the coil drive command to each transport path unit 11 to control the movement of each carriage 16 .

[0112] Fig. 9 1 is a diagram showing a configuration example of a learning device 51 included in the controller 12 of Embodiment 3. The learning device 51 includes a data acquisition unit 61 and a model generation unit 62. The data acquisition unit 61 acquires learning data and creates a data set in which the learning data is merged. The learning data is operation information and position instructions. That is, the data acquisition unit 61 acquires learning data including operation information and position instructions.

[0113] The model generation unit 62 generates a trained model using the learning data. The model generation unit 62 generates a trained model used for estimating a position command from the operating information based on the learning data.

[0114] As the learning algorithm used by the model generation unit 62, well-known algorithms such as teacher learning, teacherless learning or reinforcement learning can be used. As an example, the application of reinforcement learning in the learning algorithm used by the model generation unit 62 is described. Reinforcement learning is an intelligent agent, i.e., an acting subject, in a certain environment observes the current state and decides the action to be taken. The intelligent agent obtains rewards from the environment by selecting actions, and learns the countermeasures that obtain the most rewards through a series of actions. As representative methods of reinforcement learning, Q-learning and TD-learning are known. For example, in the case of Q-learning, the general update formula of the action value function Q(s, a), i.e., the action value table, is expressed by the following formula (1). The action value function Q(s, a) represents the value of the action of selecting action "a" based on the environment "s", i.e., the action value Q.

[0115] [Formula 1]

[0116] Q(s t , a t )←Q(s t , at )+α(r t+1 +γmax a Q(s t+1 , a t )-Q(s t , a t ))…(1)

[0117] In formula (1), “s t " represents the environment at time "t". t " represents the action at time "t". t ", the environment becomes "s t+1 ". t+1 ” represents the return brought by the change of its environment. “γ” represents the discount rate. “α” represents the learning coefficient. The operation information becomes the environment “s t ". The position instruction becomes the action "a t ”.

[0118] The update formula represented by formula (1) is that if the action value of the best action "a" at time "t+1" is greater than the action value Q of the action "a" executed at time "t", the action value Q is increased, and in the opposite case, the action value Q is decreased. In other words, the action value function Q (s, a) is updated in such a way that the action value Q of the action "a" at time "t" is close to the best action value at time "t+1". In this way, the best action value in a certain environment is continuously propagated to the action value in its previous environment.

[0119] The model generation unit 62 includes a reward calculation unit 63 and a function update unit 64. The reward calculation unit 63 calculates rewards based on the data set. The function update unit 64 updates the function for determining the position command according to the rewards calculated by the reward calculation unit 63.

[0120] Specifically, the reward calculation unit 63 calculates the reward "r" based on the number of the transmission path units 11 that perform the regenerative power supply for each control cycle. For example, a reference number, which is a reference of the number of the transmission path units 11 that perform the regenerative power supply, is set in advance. When the number of the transmission path units 11 that perform the regenerative power supply is greater than the reference number, the reward calculation unit 63 increases the reward "r". The reward calculation unit 63 increases the reward "r" by giving a reward value of "1". In addition, the value of the reward is not limited to "1". On the other hand, when the number of the transmission path units 11 that perform the regenerative power supply is less than the reference number, the reward calculation unit 63 decreases the reward "r". The reward calculation unit 63 decreases the reward "r" by giving a reward value of "-1". In addition, the value of the reward is not limited to "-1". In addition, an arbitrary number can be set for the reference number. The reference number can be set, for example, based on the total number of the transmission path units 11 constituting the transportation system 2 and the total number of the trolleys 16 constituting the transportation system 2, taking into account the size of the regenerative power or the frequency of occurrence of the regenerative power.

[0121] The function updating unit 64 updates the model for determining the position command, i.e., the function, according to the reward calculated by the reward calculating unit 63. The function can be updated according to the data set, for example, by updating the action value table. The action value table is a data set that associates any action with its action value and stores it in the form of a table. For example, in the case of Q learning, the action value function Q(s ) represented by the above formula (1) is t , a t ) is used as a function to determine the position instruction.

[0122] Fig.10 1 is a flowchart showing the processing procedure of the learning device 51 included in the controller 12 according to the third embodiment. Fig.10 Flowchart of , illustrating the reinforcement learning method for updating the action-value function Q(s, a).

[0123] In step S11, the learning device 51 acquires the operation information and the position command through the data acquisition unit 61. That is, the learning device 51 acquires the learning data. The data acquisition unit 61 outputs a data set in which the learning data is collected to the model generation unit 62.

[0124] In step S12, the learning device 51 calculates the report by the report calculation unit 63. The report calculation unit 63 calculates the report for the combination of the operation information related to each vehicle 16 and the position command related to each vehicle 16. The report calculation unit 63 increases or decreases the report based on the number of transmission path units 11 that perform regenerative power supply for each control cycle.

[0125] In step S13, the learning device 51 updates the action value function through the function updating unit 64. The function updating 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, a) stored in the trained model storage unit 52. t , a t ) to update.

[0126] In step S14, the learning device 51 determines whether the action value function Q(s, a) has converged by the function updating unit 64. The function updating unit 64 determines that the action value function Q(s, a) has converged because the action value function Q(s, a) has not been updated in step S13.

[0127] If it is determined that the action value function Q(s, a) does not converge (step S14, No), the learning device 51 returns the sequence to step S11. On the other hand, if it is determined that the action value function Q(s, a) converges (step S14, Yes), the learning device 51 ends. Fig.10 The processing involved in the sequence shown. In addition, the learning device 51 may not perform the judgment implemented in step S14, but continue learning by returning the sequence from step S13 to step S11. The trained model storage unit 52 stores the generated action value function Q (s, a), that is, the trained model.

[0128] In Embodiment 3, the case where reinforcement learning is applied to the learning algorithm used by the learning device 51 is described, but learning other than reinforcement learning may also be applied to the learning algorithm. The learning device 51 may perform machine learning using a well-known learning algorithm other than reinforcement learning, such as deep learning, neural network, genetic programming, inductive logic programming, or support vector machine.

[0129] Figure 8 and Fig. 9 The learning device 51 shown is a device built into the controller 12. The learning device 51 may also be a device external to the controller 12. The learning device 51, which is a device external to the controller 12, constitutes the conveying system 2. The learning device 51 may be a device that can be connected to the controller 12 via a network. The learning device 51 may also be a device existing on a cloud server.

[0130] The learning device 51 can learn position instructions such as the number of transmission path units 11 that perform regenerative power supply increases according to the data set created for the plurality of transmission systems 2. The learning device 51 can obtain learning data from a plurality of transmission systems 2 used in the same place, or can also obtain learning data from a plurality of transmission systems 2 used in different places. The learning data can be collected from a plurality of transmission systems 2 that operate independently of each other in a plurality of places. After the collection of learning data from the plurality of transmission systems 2 is started, a new transmission system 2 can be added to the objects from which the learning data is collected. In addition, after the collection of learning data from the plurality of transmission systems 2 is started, a part of the plurality of transmission systems 2 can be excluded from the objects from which the learning data is collected.

[0131] The learning device 51 that has learned about a certain transport system 2 may also learn about another transport system 2 other than the transport system 2. The learning device 51 that has learned about the other transport system 2 can update the trained model by relearning in the other transport system 2.

[0132] Fig.11 1 is a diagram showing a configuration example of a position command generation unit 53 included in the controller 12 according to Embodiment 3. The position command generation unit 53 has a function as an estimation device that estimates a position command based on operation information. The position command generation unit 53 includes a data acquisition unit 65 and an estimation unit 66 .

[0133] The data acquisition unit 65 acquires the inference data. The inference data is operation information related to each of the plurality of carriages 16 of the conveying 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 inputs the inference data to the trained model, thereby inferring the position instruction. The inference unit 66 outputs the position instruction as the inference result to the coil drive instruction generation unit 54. The coil drive instruction generation unit 54 generates the coil drive instruction based on the position instruction.

[0134] Fig.12 This is a flowchart showing the processing procedure of the position command generating unit 53 and the coil drive command generating unit 54 included in the controller 12 according to the third embodiment.

[0135] In step S21, the position command generation unit 53 acquires the operation information of each vehicle 16 through the data acquisition unit 65. The data acquisition unit 65 outputs the acquired operation information to the estimation unit 66.

[0136] In step S22, the position instruction generation unit 53 inputs the operation information of each vehicle 16 into the trained model in the inference unit 66, thereby generating a position instruction. In step S23, the inference unit 66 outputs the position instruction to the coil drive instruction generation unit 54. In step S24, the coil drive instruction generation unit 54 generates a coil drive instruction based on the position instruction. The above is the end of the position instruction generation unit 53 and the coil drive instruction generation unit 54. Fig.12 The controller 12 transmits the coil drive command generated by the coil drive command generating unit 54 to each transport path unit 11 via the data communication line 14 .

[0137] According to Embodiment 3, the transmission system 2 includes the learning device 51 and the position command generating unit 53 as the estimation device, thereby being able to derive a position command such that the number of transmission path units 11 supplying regenerative power increases. Thus, the transmission system 2 can appropriately handle the regenerative power.

[0138] So far, an example of applying machine learning to the generation of position instructions in the transport system 2 involved in Embodiment 2 has been described. As described in Embodiment 1, the machine learning described in Embodiment 3 can be applied to the generation of position instructions when regenerative power is supplied by the transport path unit 11 that the cart 16 does not enter. The transport system 2 may also generate position instructions by methods other than machine learning.

[0139] Next, the hardware for realizing the controller 12 according to the first to third embodiments will be described. The controller 12 is realized by a processing circuit. The processing circuit may be a circuit in which a processor executes software, or may be a dedicated circuit.

[0140] In the case where the processing circuit is implemented by software, the processing circuit is, for example, Fig.13 The control circuit shown. Fig.13 1 is a diagram showing a configuration example of a control circuit 80 according to Embodiments 1 to 3. The control circuit 80 includes 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 from the outside of the control circuit 80 and gives the data to the processor 82. The output unit 84 is an interface circuit that sends data from the processor 82 or the memory 83 to the outside of the control circuit 80.

[0141] The processing circuit is Fig.13In the case of the control circuit 80 shown in FIG. 1 , the controller 12 is implemented by software, firmware, or a combination of software and firmware. The software or firmware is described as a program and stored in a memory 83. The processing circuit reads out the program stored in the memory 83 and executes it through the processor 82, thereby realizing each function of the controller 12. That is, the processing circuit has a memory 83, and the memory 83 is used to store the program that is finally executed by the processing of the controller 12. In addition, these programs can be said to cause the computer to execute the procedures and methods of the controller 12.

[0142] The processor 82 is a CPU. The processor 82 may be a central processing unit, a processing unit, a computing unit, a microprocessor, a microcomputer, a processor, or a DSP. The memory 83 may be, for example, a nonvolatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), a flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (registered trademark) (Electrically Erasable Programmable Read Only Memory), a magnetic disk, a floppy disk, an optical disk, a compact disk, a mini disk, or a DVD (Digital Versatile Disc).

[0143] Fig.13 This is an example of hardware in which the controller 12 is realized by a general-purpose processor 82 and a memory 83 , but the controller 12 may be realized by a dedicated hardware circuit. Fig.14 This is a diagram showing a configuration example of a dedicated hardware circuit 85 according to the first to third embodiments.

[0144] The dedicated hardware circuit 85 has an input unit 81, an output unit 84, and a processing circuit 86. The processing circuit 86 is a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a circuit formed by combining them. Each function of the controller 12 can be implemented by the processing circuit 86 according to the functional category, or each function can be summarized and implemented by the processing circuit 86. In addition, the controller 12 can also be implemented by combining the control circuit 80 and the hardware circuit 85.

[0145] The structures shown in the above embodiments illustrate an example of the content of the present invention. The structures of the embodiments can be combined with other known technologies. The structures of the embodiments can also be appropriately combined with each other. Part of the structure of the embodiments can be omitted or changed without departing from the scope of the gist of the present invention.

[0146] Description of the label

[0147] 1, 2 conveying system, 10 conveying path, 11, 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H conveying path unit, 12 controller, 13 DC power supply, 14 data communication line, 15 DC power bus, 16, 16A, 16B, 16C trolley, 17A, 17B arrow, 20 coil, 21 inverter circuit, 22 current sensor, 23 capacitor, 24 current controller, 25 linear scale, 26 position sensor, 27, 82 processor, 28 communication slave station, 31P bus, 32N bus, 33 bus voltage detection unit, 34 temperature sensor, 40, 41 permanent magnet, 51 learning device, 52 trained model storage unit, 53 position instruction generation unit, 54 coil drive instruction generation unit, 61, 65 data acquisition unit, 62 model generation unit, 63 feedback calculation unit, 64 function update unit, 66 inference unit, 80 control circuit, 81 input unit, 83 memory, 84 output unit, 85 hardware circuit, 86 processing circuit.

Claims

1. A conveying system, characterized in that: A plurality of conveying path units are provided, which constitute a conveying path for the conveying body to move, and each of which is connected to a common DC bus. Each of the plurality of conveying path units includes a driving unit that generates power to move the conveying body by receiving power supplied from the DC bus. One of the plurality of conveyance path units into which the conveyance body does not enter or at least one of two or more of the conveyance path units supplies regenerative power generated in the plurality of conveyance path units to the drive unit.

2. The conveying system according to claim 1, characterized in that The transmission path unit includes a bus voltage detection unit, which detects the voltage of the DC bus, that is, the bus voltage. When the bus voltage is greater than or equal to a preset first voltage threshold, one of the plurality of transmission path units into which the transport object does not enter or at least one of two or more of the transmission path units performs the regenerative power supply.

3. The conveying system according to claim 2, characterized in that: When the bus voltage is less than or equal to a second voltage threshold value that is smaller than the first voltage threshold value, the transmission path unit that performs the regenerative electric power supply stops the regenerative electric power supply.

4. The conveying system according to claim 3, characterized in that: At least one of the first voltage threshold and the second voltage threshold is individually set in each of the plurality of transport path units.

5. The conveying system according to any one of claims 1 to 4, characterized in that: The transport path unit into which the transport body enters when the regenerative electric power supply is executed stops the regenerative electric power supply.

6. The conveying system according to any one of claims 1 to 5, characterized in that: When the regenerative electric power supply is executed, the transmission path unit stops the regenerative electric power supply when the electric power supplied to the drive unit exceeds a preset electric power threshold.

7. The conveying system according to claim 6, characterized in that The power threshold is individually set in each of the plurality of transmission path units.

8. The conveying system according to any one of claims 1 to 7, characterized in that: A detection unit for detecting the position of the conveying body is provided in the conveying path. The regenerative electric power is supplied to the transport path unit among the plurality of transport path units, the transport path unit determined that the transport object has not entered based on the detection result obtained by the detection unit.

9. The conveying system according to any one of claims 1 to 7, characterized in that: A controller is provided for controlling each of the plurality of conveying path units. The controller determines the transport path unit that performs the regenerative electric power supply based on position information indicating the position of the transport object in the transport path.

10. The conveying system according to claim 9, characterized in that The controller excludes the conveying path unit in which the conveying body exists among the plurality of conveying path units, namely the first conveying path unit, and one or more than two conveying path units located adjacent to the first conveying path unit in the conveying path, namely the second conveying path unit, from the conveying path units that perform the regenerative power supply.

11. The conveying system according to claim 10, characterized in that At least one of the number of the second conveying path units located adjacent to the first conveying path unit in a first direction along the conveying path and the number of the second conveying path units located adjacent to the first conveying path unit in a second direction along the conveying path and opposite to the first direction is calculated based on the speed of the conveying body in the conveying path.

12. The conveying system according to claim 9, characterized in that The controller excludes, from the plurality of conveying path units, the conveying path unit in which the conveying body exists, namely the first conveying path unit, and one or more than two conveying path units, namely the second conveying path units, located adjacent to the first conveying path unit in the traveling direction of the conveying body in the conveying path, from the conveying path units that perform the regenerative power supply.

13. The conveying system according to any one of claims 10 to 12, characterized in that The number of the second transport path units is calculated based on the speed of the transport body in the transport path.

14. The conveying system according to any one of claims 9 to 13, characterized in that The transport path unit has a temperature sensor, The controller determines the transmission path unit that performs the regenerative electric power supply based on the detection result of the temperature obtained by the temperature sensor of each of the plurality of transmission path units.

15. The conveying system according to any one of claims 1 to 14, characterized in that The transmission path unit includes an inverter circuit that supplies electric power converted by switching to the driving unit. The inverter circuit operates at an on-off frequency lower than an on-off frequency when the power is applied to the transport body during the regenerative electric power supply.

16. The conveying system according to any one of claims 1 to 15, characterized in that A learning device is provided, the learning device having: a data acquisition unit that acquires learning data, the learning data including operation information that is information indicating a schedule related to movement of each of the plurality of conveying bodies in the conveying path, and a position instruction related to each of the plurality of conveying bodies that indicates a position to which the conveying body is to move; as well as A model generation unit generates a trained model used for estimating the position command from the operating information based on the learning data.

17. The conveying system according to any one of claims 1 to 15, characterized in that A controller is provided, the controller having a position instruction generating unit generating a position instruction indicating a position to be moved to each of the plurality of conveying bodies, and controlling each of the plurality of conveying path units. The position instruction generating unit comprises: a data acquisition unit that acquires operation information that is information indicating a schedule related to movement of each of the plurality of transport bodies in the transport path; and The inference unit inputs the operation information into a trained model for inferring a position instruction indicating a position to be moved for each of the plurality of conveying bodies based on the operation information, thereby inferring the position instruction.

18. The conveying system according to any one of claims 1 to 17, characterized in that Having one or more of the transport bodies, The driving unit includes a coil that generates electromagnetic force as the power by power supply from the DC bus. A permanent magnet is arranged in the conveying body.

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