JP7085387B2 - Information transmission method of monitoring control system, information transmission method of monitoring control system - Google Patents

Description

The present invention relates to a technique for transmitting information between stations in a monitoring and control system layered from a lower station to an upper station via a network.

Patent Document 1 describes a control communication method between a higher-level control station and a lower-level controlled station. Here, the control station is provided with a front-end processor (Front-End Processor: hereinafter abbreviated as FEP).

This FEP exchanges formats and data common to the upper station, while exchanging formats and data specific to each device with the lower station. This absorbs the difference in communication protocol and data between the controlled station and the controlled station, and enables unified communication between them.

Patent Document 2 describes a system monitoring and control device constructed by a redundant computer system. Here, the host computer and the front-end processor are duplicated, and the line connection status between the Pronto-end processor and a large number of I / O devices is monitored and controlled.

Japanese Patent Application Laid-Open No. 10-42380 JP-A-4-31946

According to the control communication method of Patent Document 1, the data transmitted between the stations is unified and communicated by FEP. However, since the FEP has a single configuration, there is a possibility that monitoring and control between stations cannot be performed in the event of an abnormality such as a FEP failure or maintenance work.

Regarding this point, although a system monitoring control device constructed by a redundant computer system shown in Patent Document 2 has been proposed, it does not propose duplication of FEP in the information method transmission method of a control station, and monitoring between stations is not proposed. It may not be suitable for control.

The present invention has been made to solve such a conventional problem, enables monitoring control between stations in the event of an abnormality such as a FEP failure or maintenance work, and improves the reliability of information transmission of the monitoring control system. The solution is to improve.

(1) One aspect of the present invention is an information transmission method of a monitoring control system in which instantaneous data of an operating status is transmitted from a lower station to a higher station, while control data is transmitted from a higher station to a lower station.
Each of the above stations is provided with a FEP (Front-End Processor) that exchanges formats and data common to each upper station, and exchanges formats and data specific to each lower station and each device.
While multiplexing the FEP of the higher station,
The FEP of the lower station is a plurality of units according to the number of multiplexings on the upper station side.
A multiplex communication configuration with a plurality of communication systems is provided between the upper station and the lower station.
A notification for abnormality detection is reciprocated in each communication system between each FEP of the upper station and each FEP of the lower station.
It is characterized in that an abnormality in each communication system is detected based on the success or failure of the round trip of the notification.

(2) In another aspect of the present invention, the instantaneous data of the operating status is transmitted from the lower station to the upper station, while the control data is transmitted from the upper station to the lower station.
Each of the stations exchanges format and data common to the upper station, while transmitting information of a monitoring control system equipped with a FEP (Front-End Processor) that exchanges the format and data specific to the lower station and each device. It ’s a method,
A step of transmitting data by each communication system using the duplicated FEP of the upper station and the FEP of two units of the lower station.
A step of reciprocating a notification for abnormality detection to each communication system between each FEP of the upper station and each FEP of the lower station, and detecting an abnormality of each communication path based on the success or failure of the round trip of the notification. When,
It is characterized by having.

According to the present invention, it is possible to monitor and control between stations when an abnormality such as a FEP failure or maintenance work occurs. In this respect, it can contribute to improving the reliability of information transmission in the monitoring and control system.

The block diagram of the monitoring control system which concerns on embodiment of this invention. The schematic diagram of the FEP duplication. (A) is a state diagram before FEP automatic switching of Example 1, and (b) is a state diagram after FEP automatic switching of Example 1. (A) is a state diagram before FEP automatic switching of Example 2, and (b) is a state diagram after FEP automatic switching of Example 2. (A) is a state diagram before FEP automatic switching of Example 3, and (b) is a state diagram after FEP automatic switching of Example 3. (A) is a state diagram before FEP automatic switching of Example 4, and (b) is a state diagram after FEP automatic switching of Example 4. (A) is a state diagram before FEP manual switching, and (b) is a state diagram after FEP manual switching.

Hereinafter, embodiments of the present invention will be described. Here, the information transmission method of the present invention is applied to a monitoring control system, and the information transmission method of the present invention is executed.

This monitoring and control system is layered from the lower station to the upper station via the network, distinguishes between instantaneous data (monitoring information) and control data of the operating status of equipment, etc., and information between stations with different communication protocols. Perform the transmission.

Here, FEP is provided in each station as in Patent Document 1, and the difference in communication protocol and data between the upper station and the lower station is absorbed, and unified communication between them is possible.

At this time, the FEP of each station is redundant (multiplexed). Specifically, the FEP of the upper station and the FEP of the lower station are made redundant (multiplexed), and a plurality of communication systems are provided between the two FEPs. At the same time, it has an abnormality detection function for the communication system between the upper station and the lower station, improving the reliability of the monitoring and control system. The definitions of the main terms used in this embodiment are shown below.

(1) Upper station: A plurality of types of stations using the FA (Factory Automation) protocol are assumed. Here, a computer (computer) at a position that receives instantaneous data (monitoring information) of the operating status of equipment or the like from a lower station is collectively referred to as a higher station. For example, if the upper station / lower station has a relationship between the remote control system and the remote control system, the station on the remote control side corresponds to the station.

(2) Lower station: As described above, a station using the FA (Factory Automation) protocol is assumed to have a plurality of forms. Here, computers with positions that transmit instantaneous data to higher-level stations are collectively referred to as lower-level stations. For example, if the upper station / lower station has a relationship between the distance control and the distance control, the station on the distance control side corresponds to the station.

(3) FA protocol: A protocol that enables communication of FA system information between FA systems, particularly between multi-vendor systems of Patent Document 1, is referred to as "FA protocol". This FA protocol is a multi-vendor communication protocol based on TCP / IP and UDP / IP that meets the functional requirements of FA systems.

≪System configuration example≫
A configuration example of the monitoring control system will be described with reference to FIG. In this monitoring and control system, information transmission from the highest management station 11 to the control station 13 via the management station 12 is executed through the network 1.

Further, a layered information network is constructed to execute information transmission from the control station 13 to the controlled (lower) station 15 via the control (upper) station 14 through the network 2.

Here, the monitoring and control system has the features of duplication of FEP20 and 21 of both stations 14 and 15, dual communication configuration of network 2, and abnormality detection function (addition of healthy check function and communication system switching function). It differs from Patent Document 1 in that it is different from Patent Document 1. Hereinafter, the information transmission method / information transmission method of the monitoring control system will be described with a focus on this feature.

≪Duplicate FEP, etc.≫
The duplication of FEPs 20 and 21 and the dual communication configuration of the network 2 will be described with reference to FIG. 20 in FIG. 2 shows the duplicated front-end FEP-A and FEP-B of the control station (for example, a front-end pumping station) 14. Each of the long-distance control FEP-A20 and FEP-B20 is managed and controlled by a duplex controller (DC: Duplicate Controller) 24.

Further, 21 indicates a two-unit remote control FEP-A and FEP-B of a controlled station (for example, a remote control pumping station) 15, and further, 22 indicates a LAN switch.

Here, the communication systems between the control station 14 and the controlled station 15 are the A system "distance control FEP-A21 / distance control FEP-A20 system" and the B system "distance control FEP-B21 / distance control FEP-B20". It consists of two systems, "systems", and each system individually performs control communication. For this control communication, an equivalent to a conventional FEP single configuration (for example, the FEP configuration of Patent Document 1) can be used. It is assumed that the A and B systems are configured so as not to interfere with each other's control communication.

Furthermore, each of the A and B systems has a dual communication function in order to avoid network failure. That is, two communication routes, "1 system route" and "2 system route", are set in advance from the lower remote control FEP-A21, FEP-B21 to the upper remote control FEP-A20, FEP-B20. , Each route is used for communication of instantaneous data, control data, and time information.

As a result, data can be transmitted / received between the control station 14 and the controlled station 15 by the A system (1 system route, 2 system route) and the B system (1 system route, 2 system route). For example, when transmitting instantaneous data or the like from the front-end FEP-A21 or FEP-B21 to the front-end FEP-A20 or FEP-B20, the route is as follows.
・ A system 1 system route: Front-end FEP-A21 (A1) → 1 system route → Front-end FEP-A20 (A1)
2nd route: Front-end FEP-A21 (A2) → 2nd route → Front-end FEP-A20 (A2)
・ B system 1 system route: Front-end FEP-B21 (B1) → 1 system route → Front-end FEP-B20 (B1)
2nd route: Front-end FEP-B21 (B2) → 2nd route → Front-end FEP-B20 (B2)
When duplicate communication of the 1st system route and the 2nd system route is selected, the FEP on the transmitting side (for example, the remote control FEP-A21) simultaneously sends the FEP on the receiving side (for example, the far) through the 1st system route and the 2nd system route. Data is transmitted to the control FEP-A20). At this time, the FEP on the receiving side uses the data of the route received earlier as the received data (first-come-first-served basis). In the Ethernet (registered trademark) method, since the loopback method is based on high-speed detour, both the data of the 1st system route and the 2nd system route are communicated on the same route (clockwise or counterclockwise).

Here, the master-slave management of the A and B systems is performed by the duplex controller 24 that manages and controls the remote control FEP-A20 and FEP-B20. According to this master-slave management, the two front-end processors FEP-A21 and FEP-B21 execute control communication.

Further, the data reception of the remote control FEP-A20 and FEP-B20 is carried out in the main system, and the first-come-first-served data of each route (1 system route, 2 system route) of the main system is used as process data in the storage unit device of the control station 14. Stored in (not shown). On the other hand, the slave system reads the data reception memory but does not store it as process data. The far-controlled FEP-A21 and FEP-B21 transmit an uplink signal to the far-controlled FEP-A20 and FEP-B20 regardless of the master-slave of the communication system.

On the other hand, in the control information communication of the remote control FEP-A20 and FEP-B20, the control data is transmitted only in the main system under the master-slave management of the duplex controller 24, and the control data is not transmitted in the slave system. For example, when the system A is the main system, the remote control FEP-A21 that has received the control data from the remote control FEP-A20 outputs the control data to the process control system (procon) (not shown).

However, in the time synchronization between the control station 14 and the controlled station 15, the time information communication of the remote control FEP-A20 and FEP-B20 is performed by transmitting the time data from both the main system and the secondary system, and the remote control FEP. -Time synchronization can be performed for the two systems A21 and FEP-B21. At this time, the time data is output to the process control system on the main communication side of the remote control FEP-A21 and FEP-B21.

Here, although the slave communication system does not transmit or receive control data, it is assumed that TCP / IP connection is always performed for control data communication and time information communication. In this case, since the control data communication continues in a state where there is no data to be transmitted / received only by the TCP / IP connection, the TCP / IP connection confirmation (survival confirmation) may be set separately.

For the transmission convention and transmission format in FEP duplication, the single configuration convention is diverted, and the same transmission format is used for the A system and the B system.

≪Anomaly detection function, etc.≫
The duplex controller 24 manages the master-slave system of the communication system, and further detects an abnormality in each communication system. It is assumed that this master-slave system is set by default in the duplex controller 24 in advance by the manufacturer or the like. Here, as an example, it is assumed that the duplex controller 24 is set to "main system = A system" and "subordinate system = B system".

In this case, the front-end processor FEP-A20 of the A system notifies the front-end processor FEP-A21 of a healthy check (downlink) for abnormality detection using the upper master-slave division as the main code. Further, the front-end processor FEP-B20 of the B system notifies the front-end processor FEP-B21 of a healthy check (downlink) for abnormality detection using the upper master-slave system classification as the front-end processor code.

As a result, A. The master-slave system of the B system can be detected. At this time, the notification to the front-end processor FEP-A21 and FEP-B21 is transmitted at a cycle of 5 seconds, respectively. This cycle can be set to any value according to the specifications and the like.

As a response, after receiving the notification, a health check (upstream) notification is transmitted from the front-end FEP-A21 and FEP-B21 to the front-end FEP-A20 and FEP-B20. Further, the front-end processor FEP-A20 and FEP-B20 receive the healthy check (upstream) notification transmitted from the front-end processor FEP-A21 and FEP-B21.

In this way, the notification of the healthy check (down / up) is reciprocated, and the abnormality of the A and B systems is detected based on the success or failure of the reciprocation of the notification. For example, (A) down control FEP-A20, FEP-B20, (B) down control FEP-A21, FEP-B21, (C) both routes (1st route and 2nd route) are disconnected, etc. The communication system in which each of the above events occurs cannot reciprocate the notification of healthy check (downlink / uplink), and an abnormality is detected.

At this time, if an abnormality is detected in the main system A system, the main system switching, that is, the main system switching to the B system is automatically performed by the duplex controller 24. However, if an abnormality in the subordinate system (B system) is detected before switching, the main system switching is not performed.

On the other hand, if the round trip of the healthy check (downlink / uplink) notification is successful, no abnormality in the communication system is detected, and the master-slave system as before (main system = A system, without performing main system switching). Monitoring control is continued with the slave system = B system). Hereinafter, abnormality detection and main system switching will be specifically described based on Examples 1 to 4. The master-slave system management of Examples 1 to 4 is the same as the above-mentioned example.

(1) Example 1
The main system switching of the first embodiment will be described with reference to FIG. This Example 1 shows the main system switching when the distance control FEP-A21 of the main system (A system) goes down.

Here, as shown in FIG. 3A, it is assumed that the distance control FEP-A21 is down due to a failure or maintenance work. In this case, the distance control FEP-A21 cannot transmit a response to the healthy check (downlink) from the distance control FEP-A20, that is, the healthy check (uplink).

Therefore, the long-distance FEP-A20 cannot receive the healthy check (uplink), and the reception of the healthy check (uplink) times out. This timeout time can be set arbitrarily according to the specifications.

As a result, the front-end FEP-A20 detects an abnormality in the main system (A system), that is, a line disconnection of both routes of the A system (1 system route and 2 system route) / down of the far control FEP-A21, and duplicates it. The detection result is sent to the controller 24.

When this detection result is input, the duplex controller 24 switches the main system on the condition that the normal state of the subordinate system (system B), that is, the state in which no abnormality is detected continues for 15 seconds or more after the detection. implement. The confirmation of this normal state may be performed on the condition that, for example, the front-end FEP-B20 receives a healthy check (upstream) for three cycles.

As a result of this main system switching, as shown in FIG. 3B, the main system of the communication system is switched from the A system to the B system. At this time, the front-end processor FEP-B21 recognizes the switching of the communication system by the main system code of the upper master-slave division from the front-end processor FEP-B20, and executes the control communication through the 1st system route and the 2nd system route of the B system.

As a result, even if the front-end processor FEP-A21 goes down, the control communication between the stations 14 and 15 is not interrupted, and the control communication between the stations 14 and 15 is continued. Even if the distance control FEP-A21 is restored after the switching of the first embodiment, the main system of the communication system remains the B system.

(2) Example 2
The main system switching of the second embodiment will be described with reference to FIG. This Example 2 shows the main system switching when the long-distance control FEP-A20 of the main system (A system) goes down.

Here, as shown in FIG. 4A, it is assumed that the front-end processor FEP-A20 is down due to a failure or maintenance work. At this time, the long-distance FEP-A20 cannot transmit the notification of the healthy check (downlink) in the specified cycle (5-second cycle), and the untransmitted cycle is recorded.

Further, the duplex controller 24 checks the transmission record of the healthy check (downlink) every time the cycle is concerned, and detects that the front-end processor FEP-A20 is down if there is an untransmitted cycle. After this detection, the duplex controller 24 performs main system switching of the communication system on the premise that the normal state of the subordinate system (system B) continues for 15 seconds or more as in the first embodiment.

As a result of this main system switching, as shown in FIG. 4B, the main system of the communication system is switched from the A system to the B system. Here, as in the first embodiment, the distance control FEP-B21 recognizes the switching of the communication system by the main system code of the upper master-slave division from the distance control FEP-B20, and passes through the system 1 route and the system 2 route of the system B. Execute control communication.

As a result, even if the front-end FEP-A20 goes down, the control communication between the stations 14 and 15 is not interrupted, and the control communication between the stations 14 and 15 is continued.

If the front-end FEP-A20 goes down, the reception of the healthy check (downlink) also times out. Therefore, the far-controlled FEP-A21 detects an abnormality in the main system (A system), that is, a line disconnection of both routes (1 system route and 2 system route) of the A system / down of the far-controlled FEP-A20. This detection result may be sent to the duplex controller 24 through the B system to perform main system switching.

(3) Example 3
Example 3 will be described with reference to FIG. This Example 3 shows the main system switching when a line disconnection occurs in both routes (1 system route and 2 system route) of the main system (A system).

Here, as shown in FIG. 5A, the front-end FEP-A20 performed control communication by the 2nd system route because the line was cut off in the 1st system route. However, since the line was cut off on the 2nd route, the long-distance FEP-A20 could not receive the healthy check (uplink), and the reception of the healthy check (uplink) timed out.

As a result, the front-end FEP-A20 detects an abnormality in the main system (A system), that is, a line abnormality in both routes of the A system (1 system route and 2 system route) / down of the far control FEP-A21, and duplicates it. The detection result is sent to the controller 24.

When this detection result is input, the duplex controller 24 switches the main system of the communication system on the assumption that the normal state of the subordinate system (system B) continues for 15 seconds or more as in the first and second embodiments. do.

That is, as shown in FIG. 5B, the main system of the communication system is switched from the A system to the B system. At this time, the front-end processor FEP-B21 recognizes the switching of the communication system by the main system code of the upper master-slave division from the front-end processor FEP-B20.

Here, in the B system, since the 1st system route is disconnected, the control communication is executed by the 2nd system route. As a result, even if all routes (1st system route and 2nd system route) of the main system (system A) are disconnected, the control communication between stations 14 and 15 will not be interrupted, and the control communication between both systems 14 and 15 will not be interrupted. Is continued.

If the lines of both main routes are disconnected, the reception of the healthy check (downlink) also times out. Therefore, the far-controlled FEP-A21 detects an abnormality in the main system (A system), that is, a down / both routes (1 system route and 2 system route) of the far control FEP-A20. This detection result may be sent to the duplex controller 24 through the B system to perform main system switching.

(4) Example 4
Example 4 will be described with reference to FIG. As shown in FIG. 6A, the fourth embodiment shows a case where a line abnormality such as a line disconnection occurs in a single system route (system 1 route) of the main system (system A).

Here, since the main system (system A) can continue control communication by the route of system 2, as shown in FIG. 6 (b), the main system is not switched and the system A remains the main system. Monitoring control is executed.

As described above, the monitoring and control system of the present embodiment solves the problem of the conventional method in which monitoring and control between the station 14 and the station 15 cannot be performed due to a line abnormality (line disconnection, FEP failure, etc.) or maintenance work.

That is, according to the information transmission method of the present embodiment, even if the main system of the communication system is stopped due to an abnormality, the main system is automatically switched, so that the monitoring control between the stations 14 and 15 is continued. Can be done. In this respect, a highly reliable monitoring and control system can be provided.

≪Other / Other examples≫
(1) The present invention is not limited to the above embodiment, and can be modified and implemented within the scope described in each claim. For example, not only the automatic switching of the duplex controller 24 but also the main system of the communication system may be manually switched.

That is, it is assumed that the maintenance work of the remote control FEP-A20 is performed when the master-slave system is managed in the state of FIG. 7A. In this case, the main system may be switched before the maintenance work is started, and the main system may be switched from the A system to the B system as shown in FIG. 7 (b). As a result, control communication between stations 14 and 15 can be continued even during maintenance work of the remote control FEP-A20.

In addition to duplicating the FEPs 20 and 21 between stations 14 and 15, the FEPs between stations 11 and 12, stations 12 and 13, and stations 13 and 14 are duplicated (two units) for dual communication. May be planned.

In the description of the present embodiment, the master-slave of the communication system is managed by the duplex controller 24, and an abnormality of each communication system is detected. However, the remote control FEP 20 may have the function of the duplex controller 24.

(2) Further, the technical features of the present invention grasped from the above embodiments are not limited to the description of the scope of claims. An example of other technical features is shown below.

[Claim a]
While the FEP of the main system of the upper station sends a notification for abnormality detection with the upper master-slave classification as the main system to the FEP of the main system of the lower station, while
The FEP of the subordinate of the upper station sends a notification for abnormality detection with the upper master-slave division as the subordinate to the FEP of the subordinate of the lower station.
The information transmission method of the monitoring control system according to claim 2, wherein each FEP of the lower station detects the master-slave system of the communication system by receiving each of the notifications.

[Claim b]
The main FEP of the upper station sends a notification for abnormality detection to the main FEP of the lower station at an arbitrary cycle, and if the reception of the response to the notification times out, the abnormality of the main system is detected.
The information transmission method of the monitoring control system according to claim 4, wherein the duplex control unit executes main system switching when the abnormality is detected in the main system.

[Claim c]
If the main FEP of the upper station cannot send the notification for abnormality detection to the main FEP of the lower station,
The information transmission method of the monitoring control system according to claim 4, wherein the duplicated control unit detects an abnormality in the main system and further executes switching of the main system.

[Claim d]
Down of the main system FEP of the upper station Down of the main system of the lower station The main system switching is executed when each event of line disconnection of all the communication routes of the main system occurs. Or the information transmission method of the monitoring control system according to c.

[Claim e]
The information transmission method of the monitoring control system according to claim 4, b to d, characterized in that the system switching of the communication system is provided on the condition that the normal state of the subordinate system continues for a preset time after the abnormality detection of the main system is detected.

[Claim f]
In the main system switching, the FEP of the subordinate system of the upper station is switched to the main system, while the FEP of the main system is switched to the subordinate system.
The monitoring control according to claim a, wherein the FEP that becomes the new main system of the upper station after the main system is switched sends a notification for abnormality detection whose main system is the upper master-slave classification to the FEP of the lower station. Information transmission method of the system. However, it is assumed that the inventions of claims a to f are included in the technical scope of the inventions of claims 1 to 6.

1, 2, ... Network 11 ... Top management station 12 ... Management station 13 ... Control station 14 ... Control station 15 ... Controlled station 20, 21 ... FEP
22 ... LAN switch 24 ... Duplication controller (duplication control unit)

Claims (6)

It is an information transmission method of a monitoring control system in which instantaneous data of operating status is transmitted from a lower station to a higher station, while control data is transmitted from a higher station to a lower station.
The upper station includes a FEP (Front-End Processor) that exchanges data with the lower station in a device-specific format.
The lower station has a FEP that exchanges data in a format common to the upper station.
While multiplexing the FEP of the higher station,
The FEP of the lower station is a plurality of units according to the number of multiplexings on the upper station side.
A multiplex communication configuration with a plurality of communication systems is provided between the upper station and the lower station.
A notification for abnormality detection is reciprocated in each communication system between each FEP of the upper station and each FEP of the lower station.
An information transmission method for a monitoring and control system, characterized in that an abnormality in each communication system is detected based on the success or failure of the round trip of the notification. The upper station has a duplicated FEP.
The lower station is equipped with a two-unit FEP.
The communication system between the upper station and the lower station includes two systems.
While the higher-level station includes a duplex control unit that manages the master-slave system of the two systems,
The information transmission method of the monitoring control system according to claim 1, wherein each FEP of the lower station is controlled and communicated according to the management. The duplex control unit is
While transmitting the control data only in the FEP of the main system,
The information transmission method of the monitoring control system according to claim 2, wherein the control data is not transmitted in the FEP of the slave system. The duplex control unit is
If the abnormality is detected in the main system,
The information transmission method of the monitoring control system according to claim 2 or 3 , wherein the main system switching of the communication system is executed. The duplex control unit is
If the slave system detects the abnormality before the switching,
The information transmission method of the monitoring control system according to claim 4, wherein the main system switching is not executed. While instantaneous data on the operating status is transmitted from the lower station to the upper station, control data is transmitted from the upper station to the lower station.
The upper station is provided with a FEP (Front-End Processor) that exchanges data with the lower station in a device-specific format.
The lower station is an information transmission method of a monitoring control system equipped with a FEP that exchanges data in a format common to the upper station .
A step of transmitting data by each communication system using the duplicated FEP of the upper station and the FEP of two units of the lower station.
A step of reciprocating a notification for abnormality detection to each communication system between each FEP of the upper station and each FEP of the lower station, and detecting an abnormality of each communication system based on the success or failure of the round trip of the notification. When,
An information transmission method for a monitoring and control system, characterized in that it has.

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