WO2022185830A1

WO2022185830A1 - Motor system

Info

Publication number: WO2022185830A1
Application number: PCT/JP2022/004334
Authority: WO
Inventors: 良行東; 大祐福島; 敦雄長澤
Original assignee: 村田機械株式会社
Priority date: 2021-03-03
Filing date: 2022-02-03
Publication date: 2022-09-09
Also published as: TW202243388A

Abstract

A motor system (1) comprises: a motor driver (21); a plurality of motors (23); a switch unit (22); a control unit (10); and an industrial network (100). The motors (23) generate drive power through electrical power supplied by the motor driver (21). The switch unit (22) switches circuits so that the electrical power supplied by the motor driver (21) is supplied to any one of the plurality of motors (23). The control unit (10) controls the distribution of the electrical power supplied by the motor driver (21) to the plurality of motors (23) by time division. The industrial network (100) is connected to the motor driver (21), the switch unit (22), and the control unit (10), and an output control signal transmitted by the control unit (10) is transmitted to the motor driver (21), and a switching signal transmitted by the control unit (10) is transmitted to the switch unit (22).

Description

motor system

The present invention mainly relates to a motor system including a plurality of motors.

Patent Document 1 discloses a system that includes a linear motor, an arithmetic processing unit, a driver group, a coil array, and an FET-SW group. A linear motor has a plurality of movers. The arithmetic processing unit calculates a drive command value corresponding to each mover included in the linear motor. The driver comprises multiple drivers and the coil array comprises multiple coils. The processing unit selects the driver and coil according to the current position of the mover. The FET-SW group has a plurality of switches. The arithmetic processing unit switches the switches of the FET-SW group so that the drive command value is supplied to the selected driver and coil. With the above configuration, it is possible to drive the mover by supplying drive command values to the driver and the coil corresponding to the current position of the mover.

JP 2004-159385 A

Patent Document 1 does not disclose the connection method of the arithmetic processing unit, the driver group, and the FET-SW group. Depending on the connection method, delays in signal transmission may easily occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its main object is to provide a motor system having a plurality of motors, in which real-time transmission of signals is enhanced to achieve appropriate control. to provide.

Means and Effects for Solving Problems

The problem to be solved by the present invention is as described above. Next, the means for solving this problem and its effect will be explained.

According to the aspect of the present invention, a motor system with the following configuration is provided. Specifically, the motor system includes a motor driver, a plurality of motors, a switch section, a control section, and an industrial network. The motor generates a driving force by electric power supplied by the motor driver. The switch unit switches circuits so that the electric power supplied by the motor driver is supplied to any one of the plurality of motors. The control unit transmits an output control signal for controlling the power supplied by the motor driver and a switching signal for the switching unit to switch circuits, thereby time-sharing the power supplied by the motor driver. performs control for distribution to the plurality of motors. The industrial network is connected to the motor driver, the switch unit, and the control unit, transmits the output control signal transmitted by the control unit to the motor driver, and transmits the output control signal transmitted by the control unit The switching signal is transmitted to the switch section.

In general, industrial networks have a high degree of real-time signal transmission, so delays in switching signals are less likely to occur. As a result, it is possible to supply electric power to an appropriate motor to drive it, so that appropriate control can be achieved.

The motor system described above preferably has the following configuration. That is, the industrial network includes a daisy chain network. The output control signal transmitted by the control section is supplied to the motor driver via the switch section, or the switching signal transmitted by the control section is supplied to the switch section via the motor driver.

As a result, signals are transmitted sequentially through the devices connected in a daisy chain, so signal collisions are less likely to occur and high real-time performance can be achieved.

In the above motor system, it is preferable that the control unit, the motor driver, and the switch unit communicate by a broadcast polling method with the control unit as a master.

As a result, communication collisions are less likely to occur, so high real-time performance can be achieved.

It is preferable that the motor system includes a plurality of motor drivers and a plurality of switch units.

As a result, it is possible to achieve high real-time performance in controlling multiple motor drivers and multiple switch units.

In the motor system, it is preferable that the motor driver and the switch section are connected one-to-one, and the switch section supplies the electric power supplied by the corresponding motor driver to the motor.

In the motor system, the motor driver and the switch section are connected in a one-to-many correspondence, and the switch section selected from among the plurality of switch sections is supplied by the corresponding motor driver. power is preferably supplied to the motor.

In the above motor system, the motor drivers and the switch units are connected in a many-to-one correspondence, and the switch units supply power supplied by the motor driver selected from among the plurality of motor drivers. is preferably supplied to the motor.

In the above motor system, the motor is preferably a linear motor.

In the motor system described above, the motor is preferably a rotary motor.

As described above, the effects of the present invention can be exhibited in systems with various configurations.

1 is a block diagram of a motor system according to one embodiment of the present invention; FIG. FIG. 4 is a block diagram of a motor system with another network configuration; 1 is a perspective view showing an outline of a vehicle and rails driven by a motor system; FIG. The block diagram of the motor system of a 1st modification. The block diagram of the motor system of a 2nd modification.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a motor system 1 of this embodiment.

The motor system 1 is a system for controlling multiple motors. As shown in FIG. 1 , the motor system 1 includes a controller 10 , multiple motor drivers 21 , multiple switch units 22 , multiple motors 23 , and multiple encoders 24 . As will be described later, the motor system 1 may be configured to include only one motor driver 21 or may be configured to include only one switch section 22 . Although FIG. 1 and the like exemplify a configuration in which one encoder 24 is provided corresponding to one motor 23, even in a configuration in which a plurality of encoders 24 are provided corresponding to one motor 23, Alternatively, one encoder 24 may be provided for a plurality of motors 23 .

The control unit 10 is an information processing device, and includes an arithmetic device such as a CPU, and a storage device such as an HDD, an SSD, and a flash memory. The control unit 10 can perform various controls related to the motor system 1 by reading and executing the program stored in the storage device by the arithmetic device. Representative controls performed by the control unit 10 include output control, switching control, position control, and speed control (details will be described later). A section 12, a position control section 13, and a speed control section 14 are called. Note that the control unit 10 may be capable of executing controls other than those described above. A part or all of the output control section 11 , the switching control section 12 , the position control section 13 and the speed control section 14 included in the control section 10 may be provided in the motor driver 21 . That is, the control unit 10 may be provided as a separate control device from the motor driver 21 or may be incorporated in the motor driver 21 .

The motor driver 21 supplies power to the motor 23 to operate the motor. The motor driver 21 is, for example, a servo amplifier or an inverter. The motor driver 21 is controlled by the controller 10 . Specifically, the output control unit 11 of the control unit 10 generates an output control signal (preferably a current command) for determining the power supplied by the motor driver 21 and transmits it to the motor driver 21 . The motor driver 21 generates power having a waveform corresponding to the received output control signal and supplies the power to the switch section 22 . That is, the control section 10 can control the power output from the motor driver 21 according to the output control signal. In other words, the power waveform output from one motor driver 21 can be changed according to the output control signal. Note that the control unit 10 can set the destination of the output control signal.

The switch unit 22 supplies the electric power input from the motor driver 21 to the motor 23 . In this embodiment, the motor driver 21 and the switch section 22 are provided in one-to-one correspondence. Therefore, the power supplied by the motor driver 21 is always input to the corresponding switch section 22 . Although the details will be described later, the motor driver 21 and the switch unit 22 may correspond not one-to-one but one-to-many or many-to-one.

A motor driver 21 is connected to the input side of the switch section 22, and a plurality of motors 23 are connected to the output side. The switch section 22 is, for example, a switch substrate, and is configured as a circuit including a plurality of switches. By switching the switch included in the switch unit 22, the motor 23 to which power is supplied is switched. The motor 23 to which electric power is supplied is only one motor 23 among the plurality of motors 23 connected to the switch section 22 . The switch section 22 is controlled by the control section 10 . Specifically, the switching control section 12 of the control section 10 generates a switching signal for switching the switch of the switching section 22 and transmits the switching signal to the switching section 22 . The switch unit 22 switches one or more switches according to the received switching signal. As a result, power is supplied to the motor 23 specified by the control unit 10 . Note that the control unit 10 can set the transmission destination of the switching signal. Therefore, the open/closed states of the switches of the plurality of switch units 22 can be made different.

The motor 23 has a stator and a mover. One of the stator and mover contains permanent magnets and the other contains coils. When electric power is supplied to the coil from the motor driver 21, the coil becomes an electromagnet. As a result, a repulsive force or an attractive force acts between the stator and the mover, and as a result, the mover moves relative to the stator. The motor 23 of this embodiment is a linear motor in which the movable element linearly moves (sliding) with respect to the stator. Alternatively, the motor 23 may be a rotary motor in which a mover (rotor) rotates with respect to a stator (stator).

The encoder 24 is provided for each motor 23 and detects the operating state of the motor 23, specifically the relative displacement of the mover with respect to the stator. Since the motor 23 is a linear motor in this embodiment, the encoder 24 detects the position of the mover with respect to the stator (position on the moving path of the mover). The encoder 24 is, for example, a magnetic sensor provided on the movement path of the mover. If the motor 23 is a rotary motor, the encoder 24 is preferably a Hall element that detects the rotation angle of the mover, for example. A detection result of the encoder 24 is transmitted to the control unit 10 .

The control unit 10 performs position control and speed control of the mover based on the detection result of the encoder 24 . Specifically, the position control unit 13 of the control unit 10 identifies the position and movement amount of each of the movers provided in the motor system 1 based on the detection result of the encoder 24 and other information. For example, when the motor system 1 is used for transportation, the other information includes the transportation status of the article (transportation command, destination of the article) and the like. The speed control unit 14 of the control unit 10 identifies the target speed of each of the movers provided in the motor system 1 based on the detection result of the encoder 24 and other information. For example, when the motor system 1 is used for transportation, the other information includes a predetermined set speed, upper limit speed, and the like.

Next, the switching control unit 12 outputs a switching signal (in other words, the output side of the switch unit 22 corresponds to a switching signal for supplying power to the motor 23 of the mover specified by the position control unit 13 and the speed control unit 14). A switching signal for connecting to the motor 23 of . The switching control unit 12 transmits a switching signal to the switch unit 22 corresponding to the motor 23 in question.

Next, the output control unit 11 determines the power (specifically, the power waveform) to be supplied to the motor 23 based on the calculation results of the position control unit 13 and the speed control unit 14, and the motor driver 21 An output control signal is generated to supply this power. The output control unit 11 transmits an output control signal to the motor driver 21 corresponding to the motor 23 in question.

By performing the above control, the corresponding motor 23 can be driven at an appropriate direction and speed. Also, the motor 23 to which power is supplied is changed according to changes in the situation.

In this embodiment, a plurality of motors 23 correspond to one motor driver 21, and the switch unit 22 performs switching so that power is distributed to the corresponding motors 23 in a time-sharing manner. Therefore, the number of motor drivers 21 can be reduced compared to a configuration in which a motor driver 21 is provided individually for each motor 23 . As a result, the installation cost of the motor system 1 can be reduced.

Here, for example, it is assumed that the motor driver 21 switches from supplying power to a specific motor 23 (hereinafter referred to as motor A1) to supplying power to another motor 23 (hereinafter referred to as motor A2). In this case, the control unit 10 transmits to the switch unit 22 a switching signal for connecting the output side of the switch unit 22 to the motor A2, and transmits an output control signal for the motor A2 to the motor driver 21. . At this time, if the arrival of the switching signal is delayed due to, for example, a communication delay, electric power based on the output control signal for the motor A2 is supplied to the motor A1. As a result, it may become impossible to realize appropriate control.

In order to prevent this situation, the motor system 1 of this embodiment uses a configuration with high real-time communication. Specifically, the control section 10, the plurality of motor drivers 21, and the plurality of switch sections 22 are connected to each other via an industrial network. The industrial network in this embodiment is a network mainly used in factories and the like and used to control industrial machines. An industrial network is a network in which, for example, three or more devices are connected and can communicate with each other, so it differs from a standard in which two devices are connected to each other and only two devices communicate with each other. Industrial networks are different from networks commonly used in homes and offices, such as general-purpose Ethernet. The industrial network is a standard network with high real-time performance compared to general-purpose Ethernet.

The industrial network 100 of this embodiment is EtherCAT (registered trademark). As shown in FIG. 1, the industrial network 100 consists of a daisy chain network. Specifically, when the control unit 10, the motor driver 21, and the switch unit 22 are collectively referred to as a network constituent device, the second network constituent device is connected to the first network constituent device, and two network constituent devices are connected. All network constituent devices are connected in such a manner that the third network constituent device is connected to the first network constituent device. The industrial network 100 preferably constitutes a ring network, but may partially include branches.

In the industrial network 100, communication is performed using a master-slave method. The control unit 10 functions as a master, and the motor driver 21 and switch unit 22 function as slaves. Hereinafter, the motor driver 21 and the switch section 22 may be collectively referred to as slave devices. Control-related commands are transmitted from the control unit 10, which is a master. The control unit 10 transmits a control command (such as the switching signal and the output control signal described above) in a standard frame. The standard frame is returned to the control unit 10 after being sequentially transmitted to all slave devices at regular intervals. In the standard frame, bit positions and bit widths are associated in advance for each slave device. For example, the first control command for the motor driver 21 is associated with columns N to M of the standard frame. Further, each slave device stores in advance the bit position and bit width corresponding to the time. Therefore, each slave device specifies and executes the control command corresponding to itself among the control commands included in the standard frame.

In addition to the control commands, the information transmitted from the slave device to the control unit 10 (the operation status of the slave device, the detection result of the sensor, etc.) is associated in advance with the bit position and bit width for each slave device. Therefore, information to be transmitted from the slave device to the control unit 10 can also be transmitted in this standard frame.

In this embodiment, the encoder 24 is not directly connected to the industrial network 100. The detection result of the encoder 24 is transmitted to the switch section 22, and the switch section 22 carries out processing to put the detection result of the encoder 24 on the standard frame. However, the encoder 24 may be connected to the industrial network 100 if the specifications allow the encoder 24 to be connected to the industrial network.

With general-purpose Ethernet, packets are generated for each destination and transferred to the destination. Therefore, communication collisions may occur in general-purpose Ethernet (assuming that there are communication collisions). As a result, communication delays may occur irregularly, and the real-time nature of communication may deteriorate. On the other hand, in the industrial network 100 of the present embodiment, control commands for all destinations are stored in one packet, so communication collisions rarely occur. As a result, the industrial network 100 of this embodiment has high real-time communication. As described above, in the present embodiment, a situation such as the electric power for the motor A1 being supplied to the motor A2 is unlikely to occur.

　Industrial networks are not limited to EtherCAT, and may be of other communication standards. Other communication standards include, for example, CC-Link (registered trademark). When CC-Link is used, it is not necessary to be a daisy chain network. For example, as shown in FIG. 2, a branched network such as a star type may be used. In CC-Link, like EtherCAT, communication is performed by a master-slave system. Also, in CC-Link, communication is performed by a broadcast polling method. The broadcast polling method is a method that combines broadcasting to which all network constituent devices are destinations and polling in which data communication is performed after an inquiry about communication is made. More specifically, the master device first polls the slave devices individually, and the polled slave devices respond by broadcasting. After one cycle of polling slave devices, the master device transmits data to all slave devices at the same time as polling the next slave device. In CC-Link, the communication timing is managed by the control unit 10, so communication collisions rarely occur. As a result, the industrial network using CC-Link has high real-time communication.

Next, an example in which the motor system 1 of this embodiment is applied to conveying an article will be briefly described with reference to FIG. FIG. 3 is a perspective view showing an outline of a vehicle 30 and rails 35 driven by the motor system 1. As shown in FIG.

Items not shown are placed on the vehicle 30. The vehicle 30 conveys articles by traveling along rails 35 . The vehicle 30 includes a base portion 31 , wheels 32 and a mover 33 . The base portion 31 is a portion to which various members constituting the vehicle 30 are attached. The wheels 32 are attached to the base portion 31 . The mover 33 is attached to the base portion 31 and moves together with the base portion 31 . The mover 33 includes permanent magnets or coils as described above.

The rail 35 is formed along the moving route of the vehicle 30. A plurality of stators 36 and sensor pedestals 37 are attached to the rail 35 at regular intervals. Stator 36 includes permanent magnets or coils as described above. The sensor pedestal 37 is a member for mounting a magnetic sensor (not shown). With the above configuration, power is supplied to appropriate coils to generate magnetic force from the coils, and by switching the coils to which power is supplied at appropriate timing, a force is generated to move the mover 33 with respect to the stator 36. do. As a result, the vehicle 30 can run along the rails 35 .

Next, a first modification of the above embodiment will be described with reference to FIG. FIG. 4 is a block diagram of the motor system 1 of the first modified example. In the following description of the first modification and the second modification, members that are the same as or similar to those of the above-described embodiment are denoted by the same reference numerals in the drawings, and descriptions thereof may be omitted.

In the above embodiment, the motor driver 21 and the switch section 22 are in one-to-one correspondence. On the other hand, in the first modified example, the motor driver 21 and the switch section 22 are in one-to-many correspondence. In the first modification, one switch unit 22 among the plurality of switch units 22 corresponding to the motor driver 21 is connected to the motor 23 . Therefore, electric power generated by one motor driver 21 is supplied to one motor 23 via one switch section 22 .

Although there is one motor driver 21 in the first modified example, there may be a plurality of them. That is, a plurality of switch units 22 may correspond to a plurality of motor drivers 21, respectively. In the first modified example, the number of motors 23 to which the motor driver 21 can supply power is large. The first variant is therefore particularly suitable, for example, for systems in which only a few of a large number of motors operate simultaneously. The motor system 1 of the first modified example can reduce the number of motor drivers 21 compared to the motor system 1 of the above embodiment. Therefore, the installation cost of the motor system 1 can be reduced.

Next, a second modification of the above embodiment will be described with reference to FIG. FIG. 5 is a block diagram of the motor system 1 of the second modified example.

In the second modified example, the motor driver 21 and the switch section 22 are in many-to-one correspondence. The switch unit 22 of the second modification can supply electric power to the same number of motors 23 as the corresponding motor drivers 21 . As shown in FIG. 5 , in the second modification, two motor drivers 21 correspond to one switch section 22 , so the motor driver 21 can supply power to two motors 23 .

In the second modified example, the configuration of the switch unit 22 may become complicated, but the power supply destination can be switched more flexibly.

As described above, the motor system 1 includes the motor driver 21, the plurality of motors 23, the switch section 22, the control section 10, and the industrial network 100. The motor 23 generates a driving force by electric power supplied by the motor driver 21 . The switch unit 22 switches circuits so that the electric power supplied by the motor driver 21 is supplied to any one of the plurality of motors 23 . The control unit 10 transmits an output control signal for controlling the power supplied by the motor driver 21 and a switching signal for the switch unit 22 to switch circuits, thereby time-sharing the power supplied by the motor driver 21. , the control for distribution to the plurality of motors 23 is performed. The industrial network 100 is connected to the motor driver 21, the switch unit 22, and the control unit 10, transmits the output control signal transmitted by the control unit 10 to the motor driver 21, and transmits the switching signal transmitted by the control unit 10. A signal is transmitted to the switch section 22 .

In general, the industrial network 100 has a high degree of real-time signal transmission, so delays in switching signals are less likely to occur. As a result, it is possible to supply electric power to an appropriate motor 23 to drive it, so that appropriate control can be achieved.

In addition, in the motor systems 1 of the above embodiments and modifications, the industrial network 100 includes a daisy chain network. The output control signal transmitted by the control section 10 is supplied to the motor driver 21 via the switch section 22 , or the switching signal transmitted by the control section 10 is supplied to the switch section 22 via the motor driver 21 .

In addition, in the motor system 1, the control unit 10, the motor driver 21, and the switch unit 22 may communicate by a broadcast polling method with the control unit 10 as a master.

In addition, the motor system 1 of the above embodiment includes a plurality of motor drivers 21 and a plurality of switch units 22 .

As a result, it is possible to achieve high real-time performance in controlling the plurality of motor drivers 21 and the plurality of switch units 22 .

Further, in the motor system 1 of the above embodiment, the motor driver 21 and the switch section 22 are connected in a one-to-one correspondence, and the switch section 22 supplies electric power supplied by the corresponding motor driver 21 to the motor 23. supply.

Further, in the motor system 1 of the first modified example, the motor driver 21 and the switch section 22 are connected in a one-to-many correspondence, and the switch section 22 selected from among the plurality of switch sections 22 corresponds Electric power supplied by the motor driver 21 is supplied to the motor 23 .

In addition, in the motor system 1 of the second modified example, the motor drivers 21 and the switch units 22 are connected in many-to-one correspondence, and the switch unit 22 is supplied by the motor driver 21 selected from among the plurality of motor drivers 21. Power is supplied to motor 23 .

Also, in the motor system 1 of the above embodiment and modification, the motor 23 is a linear motor.

Also, in the motor system 1, the motor 23 may be a rotary motor.

Although the preferred embodiment and modification of the present invention have been described above, the above configuration can be modified as follows, for example.

In the above embodiment, the motor driver 21 is connected to the control section 10 and the switch section 22 is connected to the motor driver 21 . Therefore, the output control signal is transmitted from the control unit 10 directly or via another motor driver 21 to the corresponding motor driver 21 . The switching signal is transmitted to the switch section 22 via the motor driver 21 . Alternatively, the switch section 22 may be connected to the control section 10 and the motor driver 21 may be connected to the switch section 22 . In this case, the output control signal is sent to the motor driver 21 via the switch section 22 . The switching signal is transmitted from the control section 10 directly or via another switch section 22 to the corresponding switch section 22 .

In the above embodiment, the motor driver 21 and the switch section 22 are separate devices, but instead of this, one device having the functions of both the motor driver 21 and the switch section 22 may be provided in the motor system 1. .

In the above embodiment, an example was described in which the motor 23 was a linear motor and the motor system 1 was applied as a drive system for the vehicle 30 for transportation. Alternatively, linear motors can be applied to other devices, such as processing equipment or measuring equipment having parts that move linearly. Further, when the motor 23 is a rotary motor, the motor system 1 may be applied to a drive system of a vehicle, or may be applied to processing equipment or measuring equipment having a portion that rotates.

Reference Signs List 1 motor system 10 control unit 21 motor driver 22 switch unit 23 motor 24 encoder

Claims

a motor driver;
a plurality of motors that generate driving force from electric power supplied by the motor driver;
a switch unit for switching a circuit so that the electric power supplied by the motor driver is supplied to one of the plurality of motors;
By transmitting an output control signal for controlling the power supplied by the motor driver and a switching signal for the switching unit to switch circuits, the power supplied by the motor driver is time-divided to the plurality of motors. A control unit that controls distribution to
It is connected to the motor driver, the switch unit, and the control unit, transmits the output control signal transmitted by the control unit to the motor driver, and transmits the switching signal transmitted by the control unit to the switch. an industrial network that transmits to
A motor system comprising:
The motor system according to claim 1,
the industrial network includes a daisy chain network;
The output control signal transmitted by the control section is supplied to the motor driver via the switch section, or the switching signal transmitted by the control section is supplied to the switch section via the motor driver. A motor system characterized by:
The motor system according to claim 1,
A motor system according to claim 1, wherein said control unit, said motor driver, and said switch unit communicate with each other by a broadcast polling method using said control unit as a master.
A motor system according to any one of claims 1 to 3,
A motor system comprising a plurality of the motor drivers and a plurality of the switch units.
A motor system according to any one of claims 1 to 4,
1. A motor system according to claim 1, wherein said motor driver and said switch section are connected in a one-to-one correspondence, and said switch section supplies power supplied by said corresponding motor driver to said motor.
A motor system according to any one of claims 1 to 4,
The motor drivers and the switch units are connected in a one-to-many correspondence, and the switch unit selected from among the plurality of switch units supplies power supplied by the corresponding motor driver to the motor. A motor system characterized by:
A motor system according to any one of claims 1 to 4,
The motor drivers and the switch units are connected in a many-to-one correspondence, and the switch unit supplies electric power supplied by the motor driver selected from among the plurality of motor drivers to the motor. A motor system characterized by:
A motor system according to any one of claims 1 to 7,
A motor system, wherein the motor is a linear motor.
A motor system according to any one of claims 1 to 7,
A motor system, wherein the motor is a rotary motor.