JP6723146B2 - Driving equipment and driving equipment system - Google Patents

Description

The present invention relates to a drive device and a drive device system in a drive device system in which a load is driven by a plurality of drive devices.

BACKGROUND There is a drive device system that includes a plurality of drive devices such as an inverter or a servo amplifier that controls an electric motor, and that connects a plurality of drive devices. In a drive device system including a plurality of drive devices, a programmable logic controller (PLC) is generally used as a master device, that is, a master device, and each drive device is used as a slave device, that is, a slave device. Used. Each of the plurality of driving devices is connected to the communication device, and transmits/receives data to/from the PLC via the communication device.

On the other hand, Patent Document 1 discloses a technique for constructing a system without using a PLC by using a control device in which an inverter that drives an electric motor, an operation control unit, and a communication device are built in a housing. Has been done. Further, Patent Document 2 discloses a technique of constructing a power conversion system in which a specific inverter among a plurality of inverters having a communication function is used as a master station and a plurality of other inverters are used as slave stations. In the power conversion system described in Patent Document 2, the master station shares information with the slave station and with other devices such as a temperature sensor. As a result, the power conversion system described in Patent Document 2 does not require a PLC.

JP, 10-304696, A JP2012-170297A

However, the electric motor control system described in Patent Document 1 connects a plurality of electric motor units including an inverter, an operation control unit, and a communication device to a control network via a communication cable. Here, when the communication device is connected to a general-purpose communication line, the communication speed between the inverters becomes slow and high-precision motor control cannot be realized.

Patent Document 2 discloses a system in which an inverter having a communication function and a host control device that performs various commands is used as a master and information can be shared with a plurality of inverters through the communication function. However, since communication between a plurality of inverters is realized by a dedicated communication line, another communication line (physical layer) is required when communicating between the host controller and the inverter.

The present invention has been made in view of the above, and an object of the present invention is to obtain a drive device that can realize high-precision drive control while using a general-purpose communication line.

In order to solve the above-mentioned problems and achieve the object, a drive device according to the present invention is a drive device in a drive device system including a plurality of drive devices that drive one or more loads, and stores a sequence program. Storage unit, a sequence control unit capable of executing sequence control by executing a sequence program stored in the storage unit, and a first communication between a plurality of driving devices for sequence control, which is connected to a communication line. And a communication unit that performs second communication, which is communication other than the first communication , using a common physical layer , and a drive circuit that drives a load according to a sequence program, and the drive circuit is an inverter circuit or The communication unit is a servo amplifier and is characterized in that the second communication follows a standard protocol and the first communication follows a dedicated protocol.

The drive device according to the present invention has an effect that high-precision drive control can be realized while using a general-purpose communication line.

FIG. 3 is a diagram showing a configuration example of a drive device system according to the first embodiment. The figure which shows the structural example of the drive device of Embodiment 1. FIG. 3 is a diagram showing a configuration example of a control circuit including a processor in the first embodiment. The figure which shows the protocol layer for exclusive use of Embodiment 1, and a standard protocol layer. The figure which shows the example which connected the personal computer to the drive equipment system of Embodiment 1. FIG. 3 is a diagram showing an operation sequence between the master device and the slave device according to the first embodiment. FIG. 4 is a diagram showing an example of an operation sequence in which the master device according to the first embodiment transmits a data frame by broadcasting FIG. 3 is a diagram showing a configuration example of a drive device system according to a second embodiment.

Hereinafter, a drive device, a drive device system, and a load drive method according to an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments.

Embodiment 1.
FIG. 1 is a diagram showing a configuration example of a drive device system according to a first embodiment of the present invention. As shown in FIG. 1, the drive device system 10 of the present embodiment includes drive devices 1-1 to 1-3, electric motors 2-1 to 2-3, and a switching hub 4. That is, the drive device system 10 includes a plurality of drive devices 1-1 to 1-3 that drive the electric motors 2-1 to 2-3, respectively. The drive devices 1-1 to 1-3 and the switching hub 4 are connected by a communication line 3. As the communication line 3, for example, an Ethernet (registered trademark) communication line is used.

The drive device 1-1 drives the electric motor 2-1, the drive device 1-2 drives the electric motor 2-2, and the drive device 1-3 drives the electric motor 2-3. In the example shown in FIG. 1, the number of electric motors is three, but the number of electric motors is not limited to the example shown in FIG. 1 and may be any number. When the number of electric motors included in the drive device system 10 is k (k is an integer of 2 or more), the number of drive devices is also k. That is, a drive device is provided for each electric motor. Hereinafter, the electric motors 2-1 to 2-3 will be referred to as the electric motor 2 if they are not distinguished, and the driving devices 1-1 to 1-3 will be referred to as the driving device 1 if they are not distinguished.

FIG. 2 is a diagram showing a configuration example of the driving device 1. As shown in FIG. 2, the drive device 1 of the present embodiment includes a communication circuit 11, a communication control unit 12, a sequence control unit 13, and a drive circuit 14. The communication circuit 11 is a circuit that performs processing according to the Ethernet (registered trademark) communication protocol in the physical layer and the data link layer in the OSI (Open Systems Interconnection) reference model. The communication control unit 12 performs processing according to the communication protocol in the network layer and the layer above the network layer in the OSI reference model. The communication circuit 11 and the communication control unit 12 form a communication unit. The communication unit transmits a control command in sequence control to another drive device 1.

The sequence control unit 13 can execute sequence control by executing a sequence program, as will be described later. Further, the sequence control unit 13 is set by a parameter as described later whether to operate as a master device, that is, a master device or a slave device, that is, a slave device. The sequence control unit 13 includes a storage unit 15 for storing the sequence program.

The drive circuit 14 controls the electric motor 2 by speed control or torque control. That is, the drive circuit 14 drives the electric motor 2, which is the load to be controlled by itself, according to the sequence program. The drive circuit 14 is, for example, an inverter circuit having a switching element or a servo amplifier.

In the present embodiment, the communication circuit 11, the communication control unit 12, the sequence control unit 13, and the drive circuit 14 are mounted on the same board, for example. As a result, in the present embodiment, the communication function is built in the drive device 1, and it is not necessary to provide a communication device separately from the drive device.

In the present embodiment, it will be described that all of the driving devices 1-1 to 1-3 have the same configuration and all of the driving devices 1-1 to 1-3 can be a master device or a slave device. .. However, all of the driving devices 1-1 to 1-3 may not have the function as the master device. For example, the driving devices 1-1 and 1-2 may be driving devices that can be both master devices and slave devices, and the driving device 1-3 may be a driving device that does not have a function as a master device. .. The drive device that does not have the function as the master device may not include the sequence control unit 13, and the communication control unit 12 outputs the control command received from the master device to the drive circuit 14 and generates a response to the control command. It has only to have a function as a slave device that operates. That is, it has only to have the same function as the slave device controlled by the PLC, and the communication circuit 11 and the communication control unit 12 may be integrated by being mounted on the same substrate as the drive circuit 14.

In the present embodiment, an example in which the load driven by the drive devices 1-1 to 1-3 is the electric motor 2 will be described. However, the load driven by the drive devices 1-1 to 1-3 is the electric motor 2 The present invention is not limited to this, and may be a crane device or a lighting device. The drive circuit 14 has a function according to the load.

Next, the hardware configurations of the communication control unit 12 and the sequence control unit 13 of this embodiment will be described. The communication control unit 12 and the sequence control unit 13 are realized by a processing circuit. This processing circuit is, for example, the control circuit shown in FIG. FIG. 3 is a diagram showing a configuration example of a control circuit including a processor in the present embodiment. As shown in FIG. 3, the control circuit 100 includes a CPU (Central Processing Unit), a processor 101 such as a microprocessor, and a memory 102. When the communication control unit 12 and the sequence control unit 13 are realized by the control circuit 100 shown in FIG. 3, the processor 101 reads and executes a program stored in the memory 102 and corresponding to each control unit. To be done. The memory 102 is also used as a temporary memory in each process executed by the processor 101.

The program executed by the sequence control unit 13 is a sequence program, and the sequence program is stored in the memory 102 as described above. The sequence program may be stored in the memory 102 in advance, or may be received by the driving device 1 from another device such as an external personal computer and stored in the memory 102. As will be described later, in the present embodiment, the drive device 1 can function as either a master device or a slave device according to the parameter setting, so the memory 102 can be used as a sequence program as a master device. A sequence program for equipment and a sequence program for slave equipment are stored. The storage unit 15 is realized by the memory 102.

Next, the operation of this embodiment will be described. In the present embodiment, each drive device 1 can be set as a master device or a slave device by setting parameters. The drive device 1 set as the master device is one in the drive device system 10. The driving device 1 set as the master device may be changed as appropriate. The parameters are transmitted to the driving device 1 from, for example, an apparatus such as an external personal computer not shown in FIG. For example, when the value of the parameter is 1, it indicates that the parameter is set to the master device, and when the value is 0, it indicates that the parameter is set to the slave device. The correspondence between the parameter value and the set content is not limited to this example.

The drive device 1 set as the master device by setting the parameters will be appropriately referred to as “master device” hereinafter. The drive device 1 set as the slave device by setting the parameters is hereinafter appropriately referred to as a “slave device”. The master device monitors the control state of the slave device according to the sequence program for the master device. Specifically, the master device scans the sequence program for the slave device, that is, reads the sequence program for the slave device. Also, the master device transmits a control command to the slave device according to the control state of the slave device. Further, the slave device transmits control data to the master device according to the control command. Thereby, in the present embodiment, the master device can control the slave device by sequence control. Therefore, in the present embodiment, the PLC is not necessary, the physical layer of the communication line can be reduced, and the space and cost of the entire system can be reduced.

Further, since the master device has a fixed processing cycle for controlling the electric motor 2 controlled by itself, the drive performance for the electric motor 2 controlled by itself can be maintained by adjusting the timing for controlling the slave device. Therefore, it is possible to construct the drive device system 10 having no difference in performance from the case of using the PLC.

FIG. 4 is a diagram for explaining the communication line 3 used by the driving device 1 according to the present embodiment. The left side of FIG. 4 shows a standard protocol layer in an IP (Internet Protocol) network, and the right side of FIG. 4 shows a dedicated protocol layer used for communication between the driving devices 1 of the present embodiment. The communication between the driving devices 1 uses an Ethernet communication protocol, which is a physical layer common to the communication other than between the driving devices 1, but TCP (Transmission Control Protocol)/UDP (User Datagram Protocol) communication is used in layers above the network layer. Instead of using a standard protocol such as a protocol and an IP communication protocol, a dedicated protocol between the driving devices 1 is used.

Communication using a dedicated protocol between the drive devices 1 uses communication data in which information for distinguishing from the dedicated protocol is incorporated in a frame. The communication data realizes high speed by reducing the data amount (packet) as compared with other communication data complying with the standard protocol.

In communication between the driving devices 1, a control command by sequence control and a transfer of control data between the driving devices are exchanged, so that a dedicated protocol using a predetermined format can be defined. For example, by making the header shorter than the header in the IP communication protocol, it is possible to perform higher speed communication than the standard communication protocol.

Since the physical layer and the data link layer use the Ethernet communication protocol, communication data according to the above-described dedicated protocol, HTTP (HyperText Transfer Protocol), and FTP (File Transfer Protocol) in the standard protocol layer are used in the communication line 3. ), and communication data according to a protocol such as Modbus (registered trademark)/TCP can coexist.

As described above, in the present embodiment, communication between a plurality of driving devices is performed in the physical layer according to the same protocol as other communication, and in the network layer and above layers according to a protocol different from other communication. An example of another communication is communication according to the Internet Protocol (IP), which includes communication between the drive device 1 and an external personal computer that does not require high-speed communication, and communication that is not related to sequencer control.

FIG. 5 is a diagram showing an example in which the personal computer 6 is connected to the drive device system 10 of the present embodiment. As shown in FIG. 5, when the personal computer 6 is connected to the communication line 3, in the driving device system 10 of the present embodiment, TCP/IP communication and UDP/IP communication between the personal computer 6 and the driving device 1, Communication between the drive devices 1 can be implemented in the same physical layer via the switching hub 4.

In this way, the personal computer 6 connected to the communication line 3 sets display parameters for each driving device 1, transmits a sequence program to the driving device 1, and displays data for monitoring the state of each driving device 1. May be transmitted. At this time, as described above, the communication between the personal computer 6 and the driving device 1 uses the Ethernet protocol of the same physical layer, but the standard protocol is used in the upper layer.

Further, as shown in FIG. 5, by setting a VLAN (Virtual Local Area Network) 5 between the driving devices 1, communication between the driving devices 1 can be preferentially processed. For example, a VLAN identifier is assigned to the MAC (Media Access Control) address of each driving device 1, and the switching hub 4 is set to give priority to the communication of the VLAN identifier. As a result, the communication between the drive devices 1 can be preferentially processed. That is, the communication between the plurality of driving devices 1 is performed using the VLAN 5, and in the communication line 3 to which the plurality of driving devices 1 are connected, the VLAN communication corresponding to the communication between the plurality of driving devices 1 is another communication. It is set to have higher priority.

By setting the VLAN 5 in addition to using a dedicated protocol for communication between the driving devices 1, sequencer control between the driving devices 1 can be realized at higher speed and with higher accuracy. Since the synchronous control of the plurality of electric motors 2 is important when driving the electric motors 2, it is important to preferentially perform communication between the driving devices 1 in order to improve the driving performance.

FIG. 6 is a diagram showing an operation sequence between the master device and the slave device according to the present embodiment. The master device can perform both a method of transmitting a data frame to each slave device by unicast and a method of transmitting a data frame to each slave device by broadcast, and either one is selected and implemented. The master device selects, for example, whether to transmit the data frame by broadcast or unicast according to the content of the read sequence program. FIG. 6 shows an example in which the master device transmits a data frame to each slave device by unicast. Note that FIG. 6 shows an example in which one master device and three slave devices are connected to the network, and the three slave devices are described as slave #1, slave #2, and slave #3, respectively. Also, the station numbers of slave #1, slave #2, and slave #3 are number 1, 2, and 3, respectively. In the figure, the master device is abbreviated as the master.

As shown in FIG. 6, the master device first scans the sequence program of each drive device (step S1). Specifically, the sequence control unit 13 reads the sequence program for the master device and the sequence program for each slave device stored in the storage unit 15. These sequence programs are sequence programs for each drive device 1 to drive the electric motor 2, and include a control command indicating a control command for the drive circuit 14 of the drive device 1 and control data measured in the drive circuit 14. A control command for requesting acquisition is included.

Next, the master device unicasts the data frame storing the control command to the slave #1 having the station number 1 (step S2). Specifically, the sequence control unit 13 passes a control command to be transmitted to the slave #1 to the communication control unit 12, the communication control unit 12 stores the control command in a data frame according to a dedicated protocol, and the slave unit is set as a destination of the data frame. The station number corresponding to #1 is stored, and the data frame is transmitted via the communication circuit 11. When the slave #1 receives the data frame from the master device, the slave #1 transmits the data frame storing the response signal to the master device (step S3). Specifically, in the slave device, when the communication control unit 12 receives the data frame via the communication circuit 11, the control command is extracted from the data frame and passed to the sequence control unit 13, and the response data is transmitted to the master device. .. The sequence controller 13 controls the drive circuit 14 according to the control command. The response frame may include control data indicating the control state of the drive circuit 14 or control data indicating the state of the electric motor 2 generated by the sequence control unit 13.

Similarly, the master device transmits a data frame storing a control command by unicast to slave #2 having a station number of 2 (step S4). When the slave #2 receives the data frame from the master device, the slave #2 transmits the data frame storing the response signal to the master device (step S5). Similarly, the master device unicasts a data frame storing a control command to slave #3 having a station number of 3 (step S6). When the slave #3 receives the data frame from the master device, the slave #3 transmits the data frame storing the response signal to the master device (step S7).

Then, again, the master device first scans the sequence program of each drive device (step S8). Then, steps S9 to S14 are carried out similarly to steps S2 to S7. Since the time from the end of step S1 (that is, the end of the scan to the transmission of the data frame by the master device to each slave) is constant and the time required for the scan is also constant, the scan of the sequence program is started. The communication cycle of the communication between the master device and the slave device can be set to an arbitrary value by adjusting the timing to be performed. For example, the sequence control unit 13 of the master device outputs a control command to the drive circuit 14 according to the sequence program of the master device between step S1 and step S2. That is, the processing cycle in which the drive circuit 14 of the master device executes the control command and the communication cycle can be the same. Alternatively, the communication cycle may be an integral multiple of the processing cycle in which the drive circuit 14 of the master device executes the control command.

FIG. 7 is a diagram showing an example of an operation sequence in which the master device transmits a data frame by broadcasting. As shown in FIG. 7, the master device scans the sequence program as in step S1 of FIG. 6 (step S21). Next, the master device transmits the control command to all slave devices by broadcasting (step S22). Specifically, the sequence control unit 13 passes a control command to be transmitted to all slaves to the communication control unit 12, the communication control unit 12 stores the control command in a data frame according to a dedicated protocol, and broadcasts it to the destination of the data frame. The identification information shown is stored, and the data frame is transmitted via the communication circuit 11.

When the slaves #1, #2, and #3 receive the data frame from the master device, the slaves #1, #2, and #3 respectively transmit the data frames storing the response signals to the master device (steps S23, S24, and S25). Thereafter, steps S26 to S30 are carried out similarly to steps S21 to S25.

As described above, in the present embodiment, each drive device 1 has a function of performing sequence control and has a built-in communication function. Then, one of the driving devices 1 is set as a master device, the other driving devices 1 are set as slave devices, and these driving devices 1 are connected by the Ethernet protocol, and the master device reads the sequence program, A data frame was sent to a slave device according to a dedicated protocol. Therefore, the drive device system 10 of the present embodiment can perform highly accurate sequence control without using a PLC and using a general-purpose communication line. Therefore, space saving and cost reduction can be achieved.

That is, according to the present embodiment, communication is performed by the dedicated protocol between the driving devices 1 using the physical layer common to the standard protocol, and therefore, different from the standard protocol, such as optical communication and serial communication. Does not require a physical layer. Therefore, since it is not necessary to add a new communication line to the general-purpose communication line, high-speed communication can be realized between the drive devices 1 without increasing the number of communication lines.

Further, by appropriately setting the communication cycle of communication between the master device and the slave device, sequence control can be realized without disturbing the control operation of the electric motor 2 in the master device.

In addition, when the master device deteriorates or fails in the drive device 1 set as the master device, the other drive device 1 is changed from the slave device to the master device by changing the parameter of the other drive device 1 having the master function. Can be changed to equipment.

Embodiment 2.
FIG. 8 is a diagram showing a configuration example of a drive device system according to the second exemplary embodiment of the present invention. As shown in FIG. 8, drive device system 10a of the present embodiment includes drive devices 1-1 to 1-3, electric motor 2, and switching hub 4. The drive devices 1-1 to 1-3 are connected by a communication line 3 via a switching hub 4. The components having the same functions as those in the first embodiment are designated by the same reference numerals as those in the first embodiment, and the duplicated description will be omitted.

The configurations and operations of drive devices 1-1 to 1-3 of the present embodiment are similar to the configurations and operations of drive devices 1-1 to 1-3 of the first embodiment. In the present embodiment, the drive devices 1-1 to 1-3 control one electric motor 2. The drive circuits 14 of the drive devices 1-1 to 1-3 are connected in parallel to the electric motor 2.

In the first embodiment, the plurality of drive devices control different electric motors 2, respectively. In the present embodiment, the drive devices 1-1 to 1-3 synchronously control one electric motor 2. Therefore, the master device controls the electric motor 2 in accordance with its own sequence program, and at the same time, transmits a control command to each slave device in accordance with its own sequence program. The control command and control data are transmitted according to a dedicated protocol as in the first embodiment. As a result, the transfer of control commands and control data between the driving devices 1-1 to 1-3 can be realized at high speed. Therefore, the slave device can output a voltage equivalent to that of the master device to the electric motor in synchronization with the master device, and by connecting a plurality of drive devices 1 to one electric motor 2 in parallel, a large capacity can be obtained. It is possible to realize the parallel operation in which the motors are driven by the electric power.

The configurations described in the above embodiments are examples of the content of the present invention, and can be combined with other known techniques, and the configurations of the configurations are not departing from the scope of the present invention. It is also possible to omit or change parts.

1, 1-1 to 1-3 drive equipment, 2, 2-1 to 2-3 electric motors, 3 communication lines, 4 switching hubs, 5 VLANs, 6 personal computers.

Claims (7)

The drive device in a drive device system comprising a plurality of drive devices for driving one or more loads,
A storage unit for storing the sequence program,
A sequence control unit capable of executing sequence control by executing the sequence program stored in the storage unit,
Communication connected to a communication line and performing first communication between the plurality of drive devices for the sequence control and second communication other than the first communication using a common physical layer Department,
A drive circuit for driving a load according to the sequence program;
Equipped with
The drive circuit is an inverter circuit or a servo amplifier,
The driving device, wherein the communication unit performs the second communication according to a standard protocol and the first communication according to a dedicated protocol. The drive device according to claim 1, wherein the first communication has a higher communication speed than the second communication . A drive device system comprising a plurality of drive devices for driving one or more loads,
The master device, which is one of the plurality of drive devices,
A storage unit for storing the sequence program,
A sequence control unit capable of executing sequence control by executing the sequence program stored in the storage unit,
Carried out using the common physical layer first communication for the sequence control, the second communication is a first communication other than the communication, the between the slave device which is another of the drive device Communication department,
A drive circuit for driving a load according to the sequence program;
Equipped with
The drive circuit is an inverter circuit or a servo amplifier,
The drive device system, wherein the second communication follows a standard protocol and the first communication follows a dedicated protocol. The drive device system according to claim 3, wherein the second communication is communication between the master device and an external device. Wherein the first communication, the drive device system according to claim 4, wherein the go fast communication speed than the second communication. The drive device system according to claim 5, wherein the first communication and the second communication are mounted on the same physical layer via a switching hub. The drive device system according to claim 6, wherein communication from the master device to the slave device is performed with priority over other communication using a virtual local area network.

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