JP2006345221A - Monitoring device, process facility base, and supervisory control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent data from being lost owing to a discrepancy of master station/slave station status recognition between a transmission-side station and a reception-side station when a supervisory control system for town gas supply uses double redundant lines. <P>SOLUTION: A master station 1 has a data-transmission-timing-by-line table 11 showing transmission timings of health check data transmitted to a slave station 2 and actuation timings of a control event transmission processing part 18, a fixed-period transmission processing section 17 which transmits the health check data by using both lines 12A and 12B and also actuates the control event transmission processing section 18 according to the timings shown in the table, and a line selection switch 111 which selects the lines 12A or 12B to be used to transmit control data by the control event transmission processing section 18, which is configured to transmit the control data by using the line 12 selected by the line selection switch 111. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a monitoring apparatus, a process facility base and a monitoring control system in city gas supply.

2. Description of the Related Art Conventionally, in city gas supply, there is a monitoring control system that performs remote monitoring control of a process facility base (hereinafter referred to as a slave station) in a concentrated manner by a monitoring device (hereinafter referred to as a parent station).
In this supervisory control system, in order to ensure the toughness against the occurrence of a communication path failure, a method of making the communication line connecting the master station and the slave station double redundant with different lines (for example, a satellite line and a digital dedicated line) Has been taken. In such a supervisory control system, one line is set as the primary system and the other line is set as the secondary system, and when a failure occurs in the primary system line, the switching process to the secondary system is performed. . Here, the data transmitted from the master station to the slave station is, for example, a control message (control signal, control data) for performing remote control to the slave station, and checking whether the slave station and line are functioning normally. This is health check data. The data transmitted from the slave station to the master station is, for example, a response to the content instructed by the control message from the master station, measurement data measured by the slave station sensor, or the like.
Japanese Unexamined Patent Publication No. 09-327078 (paragraph number [0012], FIG. 1) Japanese Unexamined Patent Publication No. 2000-36987 (paragraph number [0007], FIG. 1)

  However, according to the conventional technology, in the main / slave line switching of the dual redundant line, the transmission side station and the reception side station recognize the status as to whether it is the primary system or the secondary system. There was a problem that data could be lost due to inconsistencies. For example, if the transmitting station recognizes the digital private line as the main line, but the receiving station recognizes the satellite line as the main line, the transmitting side station There is a problem in that data transmitted on the line is not received by the receiving station and data is lost.

  The present invention provides a monitoring apparatus, a process equipment base, and a monitoring control system that solve the above-described problems and prevent data loss due to a master / slave status recognition mismatch between a transmitting station and a receiving station. This is the issue.

  In order to solve the above-described problems, the present invention performs monitoring and control for one or more process equipment bases that are distributed, so that various data can be transmitted and received with each of the process equipment bases using a dual redundant line. A monitoring event to be performed, a control event transmission processing unit that transmits control data related to a control event that has occurred in the monitoring device, and a fixed-cycle data to be transmitted to the process facility base for each line that constitutes the dual redundant line Line-specific data transmission timing table showing transmission timing and start timing of a control event transmission processing unit that transmits control data related to a control event generated in the monitoring device, and timings shown in the line-specific data transmission timing table And transmitting the periodic data from both lines of the double redundant line, In addition, the fixed-cycle transmission processing unit that activates the control event transmission processing unit, and the control event transmission processing unit, the line used at the time of transmission of the control data is any of the double redundant lines for each process equipment base A line selection unit that selects one of the lines, and the control event transmission processing unit transmits the control data to each process facility base using the line selected by the line selection unit. . Other configurations will be described in the section of the best mode for carrying out the invention.

  According to the present invention, in a system that monitors remote stations from a master station, such as a city gas supply monitoring and control system, data continuity and reliability can be maintained even when a dual redundant line is used. Can be secured. That is, for example, data loss due to mismatch in master / slave status recognition between the transmitting station and the receiving station is prevented.

  Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings. Note that the monitoring control system in the present embodiment will be described by taking as an example a case where the monitoring control system is applied to monitoring control of city gas supply. In each figure, the solid line indicates the flow of processing, and the broken line indicates the data flow.

  FIG. 1 is a block diagram showing a functional development of the configuration of the monitoring control system of the present embodiment. As shown in FIG. 1, the supervisory control system includes a master station (monitoring device) 1 and one or more slave stations 2 (2A to 2N). The master station 1 is a city gas supply monitoring device, for example, and the slave stations 2 (2A to 2N) are city gas supply equipment bases (process equipment bases) distributed in each region. The master station 1 and the slave station 2 are connected by a line 12A and a line 12B. That is, the master station 1 and the slave station 2 are connected by two types of lines (double redundant lines). The line 12A is, for example, a digital dedicated line, and the line 12B is, for example, a satellite line.

  The master station 1 transmits a control signal (control data) to the slave station 2 via the line 12A or the line 12B. The slave station 2 that has received the control data executes a control process according to the control data and transmits response data of the control data to the master station 1. Based on the response data received from the slave station 2, the master station 1 confirms that the control in the slave station 2 is executed. In addition, the master station 1 receives various measurement data from the slave station 2 every predetermined period. Thereby, the supply amount of gas in each slave station 2 is grasped.

  Further, the master station 1 transmits data (health check data) for checking whether or not a failure has occurred in the lines 12A and 12B to the slave station 2 every predetermined period. The slave station 2 stores the value of the time stamp of the previous health check data in a memory or the like, and when a certain period of time has passed since the previous data reception, a failure has occurred in the line 12 (12A, B). to decide.

(master station)
Next, the configuration of the master station 1 will be described. The master station 1 includes a network transmission / reception unit 13, a control processing unit 14, a transmission request interface 15, a transmission data buffer 16, a periodic transmission processing unit (transmission processing unit) 17, a control event transmission processing unit 18, A transmission buffer management table 19, a transmission sequence number management table 10, a line-specific data transmission timing table 11, and a line selection switch 111 (111A to 111N) are configured.

  The master station 1 includes an arithmetic processing unit such as a CPU (Central Processing Unit), a storage unit such as a memory, an input / output interface for transmitting / receiving data via the lines 12A and B, a communication unit, and switching between the lines 12A and B. It is configured to include a switch for performing the above. The storage unit stores various programs such as a network OS (Operating System) and middleware for realizing the communication method of the present embodiment.

  The network transmission / reception unit 13 transmits / receives various data via the line 12. The network transmission / reception unit 13 is realized by execution processing of the communication unit, the switch, the input / output interface, the CPU network OS, middleware, and the like. For example, the network transmitting / receiving unit 13 transmits control data created by the control processing unit 14 to be described later, health check data to the slave station 2, or response data transmitted from the slave station 2 (response data for control data). And receiving various measurement data.

  The control processing unit 14 creates transmission data (such as health check data and control data) to the slave station 2 and sends a transmission request for the transmission data to the control event transmission processing unit 18 via the transmission request interface 15. Further, the control processing unit 14 receives measurement data and the like (described later) of the gas supply amount transmitted from the slave station 2 via the network transmission / reception unit 13 and stores the measurement data in a memory or the like.

Here, the measurement data transmitted by the slave station 2 may be transmitted simultaneously from both the high speed line (line 12A) and the low speed line (line 12B) (data transmission by line in FIG. 3B described later). (Refer to “0 seconds” and “12 seconds” in the timing table 11), the control processing unit 14 of the master station 1 may receive measurement data having the same time stamp value and the same serial number in duplicate. In this case, it is assumed that the control processing unit 14 adopts the first arrival data among the received measurement data and stores it in a memory or the like.
In this way, even when a dual redundant line is used for connection between the master station 1 and the slave station 2, the master station 1 performs communication without being aware of which line is the used line. be able to.
Note that the slave station 2 simultaneously loads the same measurement data from both the high-speed line (line 12A) and the low-speed line (line 12B), so that the load of the duplicate data determination process in the parent station 1 is increased. Can be reduced. That is, when the slave station 2 receives the data on the master station 1 side by transmitting the measurement data using both the lines 12A and 12B, the slave station 2 uses the same serial number and the same time stamp value. Thus, it is possible to accurately and easily determine that the received data is duplicate data.

  The transmission request interface 15 registers the transmission request from the control processing unit 14 in the transmission buffer management table 19. Further, the transmission request interface 15 notifies the transmission request to the control event transmission processing unit 18 by editing the transmission data into a predetermined electronic message format and registering it in the transmission data buffer 16. The transmission request interface 15 corresponds to management table registration means in the claims.

  The control processing unit 14 and the transmission request interface 15 are realized by the above-described program execution processing by the CPU.

  The transmission data buffer 16 is a buffer for transmission data (health check data and control data) edited in a predetermined message format, and is configured from a plurality of surfaces. The number of transmission data buffers 16 is determined by the type of transmission data and the frequency of occurrence of control events. The transmission data buffer 16 is formed on the memory described above.

  The transmission buffer management table 19 shows transmission requests and usage states (management information for each surface of the transmission data buffer 16) on each surface of the transmission data buffer 16. For example, the transmission buffer management table 19 includes status information regarding whether the transmission data buffer 16 is empty or a transmission request, the station number (station ID) of the destination station of the transmission data, and the transmission It includes a message ID that is the type of data, a transmission sequence number that is the sequence number of the transmission data, and a time stamp.

  The transmission sequence number management table 10 is a table showing transmission sequence numbers added to transmission data. The transmission buffer management table 19 and the transmission sequence number management table 10 are stored in the memory described above.

  The periodic transmission processing unit 17 transmits health check data via the network transmission / reception unit 13 every predetermined period. In the data transmission at this time, the periodic transmission processing unit 17 reads the health check data from the transmission data buffer 16 and transmits it. In addition, the periodic transmission processing unit 17 activates the control event transmission processing unit 18 every predetermined period. The transmission of the health check data and the activation of the control event transmission processing unit 18 at this time are performed with reference to the timing described in the line-specific data transmission timing table 11.

  The data transmission timing table 11 for each line (hereinafter referred to as a transmission timing table) includes a timing (periodic data transmission period) at which the periodic transmission processing unit 17 of the master station 1 transmits health check data and a control event for each line. This is information indicating the timing (activation cycle) at which the transmission processing unit 18 is activated. Details of this transmission timing table will be described later with reference to FIG. The transmission timing table 11 is stored in the above-described memory, and can be rewritten when the administrator of the system inputs setting information via the input / output interface.

  The control event transmission processing unit 18 performs transmission processing of data related to the control event (control data). The transmission process at this time uses the line 12 (line 12A or line 12B) selected by the line selection switch 111 (111A to 111N). The line selection switch 111 (111A to 111N) corresponds to a line selection unit in the claims.

  The line selection switch 111 (111A to 111N) is provided for each slave station 2 (2A to 2N). For example, the line 12 connected to the slave station 2A is selected by the line selection switch 111A and connected to the slave station 2B. The line selection switch 111B selects the line 12 to be performed. That is, if the line selection switch 111A selects the line 12A, the control event transmission processing unit 18 instructs the network transmission / reception unit 13 to use the line 12A for communication with the slave station 2A. If the line selection switch 111B has selected the line 12B, the control event transmission processing unit 18 instructs the network transmission / reception unit 13 to use the line 12B for communication with the slave station 2B.

  Here, the line selection switch 111 selects the line 12 (line 12A or line 12B) based on the instruction information input via the input / output interface of the master station 1. The instruction information at this time may be input directly via an input means (keyboard, mouse, etc.) connected to the master station 1, or may be input via another network. The line selection switch 111 detects when a failure occurs in one line 12 (for example, the line 12A) and transmits data to the network transmission / reception unit 13 through the other line 12 (for example, the line 12B). You may be instructed to do so.

  Here, the master station 1 switches the control data transmission line to either the line 12 (line 12A or line 12B) because the control data is transmitted from both lines of the line 12 (12A, B). This is because the slave station 2 may cause confusion in the control processing. That is, the slave station 2 prevents the control process from being confused by receiving the same control data twice.

  The fixed-cycle transmission processing unit 17 and the control event transmission processing unit 18 are realized by a program execution process by the CPU.

(Slave station)
Next, the configuration of the slave station 2 will be described with reference to FIG. FIG. 2 is a block diagram showing the expanded configuration of the slave station of FIG. Since the slave stations 2 (2A to 2N) have the same configuration, the configuration of the slave station 2A will be described as a representative here.

  The slave station 2A includes a network transmission / reception unit 23, a control processing unit 24, a transmission request interface 25, a transmission data buffer 26, a periodic transmission processing unit (transmission processing unit) 27, and a data transmission timing table for each line (transmission). (Timing table) 21, control event transmission processing unit 28, transmission buffer management table 29, transmission sequence number management table 20, and line selection switch 211. Since the slave station 2A has substantially the same configuration as that of the master station 1, the description of the same configuration as the master station 1 is omitted, and a configuration having a function different from that of the master station 1 (the control processing unit 24 and the fixed period) The transmission processing unit 27) will be described.

The control processing unit 24 creates transmission data to the master station 1 (measurement data and response data to the control data from the master station 1), and sends the transmission data to the control event transmission processing unit 28 via the transmission request interface 25. Request to send.
For example, the control processing unit 24 of the slave station 2 </ b> A creates measurement data based on the measurement value acquired from the sensor of the slave station 2 </ b> A and transmits it to the master station 1 via the network transmission / reception unit 23. Further, when the slave station 2A receives the control data from the master station 1, the slave station 2A executes a control process based on the control data. Then, response data indicating that this control process has been executed is created and transmitted to the master station 1 via the network transmission / reception unit 23.

  Note that the measurement data and response data at this time are stored in the memory as the transmission data buffer 26 via the transmission request interface 25.

  Here, the measurement data is transmitted to the partner station (master station 1) every predetermined period. The procedure at this time is the same as the procedure for transmitting health check data from the master station 1 to the slave station 2 described above. That is, the fixed-cycle transmission processing unit 27 of the slave station 2A refers to the transmission timing table 21 to determine the transmission timing from the high-speed line (line 12A) and the transmission timing from the low-speed line (line 12B). Send.

  Then, the periodic transmission processing unit 27 activates the control event transmission processing unit 28 based on the transmission timing table 21, and the control event transmission processing unit 28 transmits the response data via the network transmission / reception unit 23. Also at this time, the control event transmission processing unit 28 transmits data from the line 12 (lines 12A and 12B) selected by the line selection switch 211.

  At this time, the control processing unit 24 includes the transmission serial number assigned to the received control data and the station number (station ID) of the slave station 2A in the response data transmitted to the master station 1. By doing so, the control processing unit 14 of the master station 1 can check to which control data the response data is a response when the response data is received.

  Further, the control processing unit 24 performs a health check on the lines 12A and 12B based on the loose check data from the master station 1 received via the network transmitting / receiving unit 23. The health check here records the time stamp value of the previous health check data, and when the next health check data does not arrive even after a predetermined time has elapsed from this value, the line 12 (12A, B) It is determined that some abnormality has occurred. Then, the determination result is notified to, for example, an administrator of the monitoring control system.

  The fixed-cycle transmission processing unit 27 transmits data measured by a sensor (not shown) of the slave station 2A to the master station 1 every predetermined period. The station ID is also included in this data (measurement data). In this way, the master station 1 can identify which slave station 2 the measurement data transmitted from each slave station 2 is from.

  Next, a data transmission procedure from the master station 1 to the slave stations 2 (2A to 2N) will be described with reference to FIGS.

FIG. 3A is a flowchart illustrating a processing procedure of the fixed-cycle transmission processing unit of the master station in FIG. (B) is a diagram exemplifying a data transmission timing table for each line of the master station in FIG.
With reference to FIGS. 1 and 2, the processing procedure of the fixed-cycle transmission processing unit 17 of the master station 1 will be described with reference to FIG.

  First, an administrator of this monitoring control system sets the transmission timing table 11 (see FIG. 3B). The transmission timing table 11 includes a timing (periodic data transmission cycle) at which the periodic transmission processing unit 17 of the master station 1 transmits health check data of the periodic transmission processing unit 17 and a control event transmission processing unit 18 for each line. This is information indicating the timing of activation (activation period of the control event transmission processing unit 18). Details of the transmission timing table 11 will be described later with reference to FIG.

  The fixed-cycle transmission processing unit 17 is activated by its own scheduler (timer) (S31). At this time, the period activated by the scheduler is set to an interval at which continuous transmission is possible on the high-speed line (line 12A) of the lines 12 (12A, B). This interval is, for example, an interval of 1 second.

  Next, the periodic transmission processing unit 17 refers to the transmission timing table 11 to determine whether or not it is time to transmit the periodic data (health check data) for each line 12 (12A, B). It is determined whether or not the periodic transmission timing has come.

  Specifically, first, the periodic transmission processing unit 17 refers to the transmission timing table 11 and determines whether the periodic transmission timing of the high-speed line (line 12A) has come (S32). Here, when the fixed-cycle transmission timing of the high-speed line (line 12A) has come (Yes in S32), the process proceeds to S33 to determine whether the fixed-cycle transmission timing of the low-speed line (line 12B) has come. (S33). When the fixed-cycle transmission processing unit 17 determines that the fixed-cycle transmission timing of the low-speed line (line 12B) has come (Yes in S33), the high-speed line (line 12A) and low-speed line (line 12B) are used. The health check data is transmitted to the slave station 2 (S34). Then, the periodic transmission processing unit 17 once ends the process and waits for the next activation timing.

  On the other hand, when it is determined in S32 that the fixed-cycle transmission timing of the high-speed line (line 12A) has not yet arrived (No in S32), the fixed-cycle transmission processing unit 17 activates the control event transmission processing unit 18 (S35). ). Then, the periodic transmission processing unit 17 causes the control event transmission processing unit 18 to transmit control data according to the transmission buffer management table 19.

  That is, if the high-speed line (line 12A) is selected in the line selection switch 111A, the control event transmission processing unit 18 transmits control data from the high-speed line (line 12A). On the other hand, when the low speed line (line 12B) is selected in the line selection switch 111A, the control event transmission processing unit 18 does not transmit control data.

  In S33, when it is determined that the fixed-cycle transmission timing of the high-speed line (line 12A) has come, but the fixed-cycle transmission timing of the low-speed line (line 12B) has not arrived yet (No in S33), the fixed period The transmission processing unit 17 transmits health check data (fixed period data) from the high-speed line (12A) and activates the control event transmission processing unit 18 (S36). Then, the periodic transmission processing unit 17 causes the control event transmission processing unit 18 to transmit control data from the low speed line (line 12B) according to the transmission buffer management table 19.

  Also at this time, if the low speed line (line 12B) is selected in the line selection switch 111A, the control event transmission processing unit 18 transmits control data from the low speed line (line 12B). On the other hand, when the low speed line (line 12B) is not selected in the line selection switch 111A (the high speed line (line 12A) is selected), the control event transmission processing unit 18 does not transmit control data.

Here, the above-described transmission timing table will be described with reference to FIG. 3B (see FIGS. 1 to 3A as appropriate).
In the transmission timing table of FIG. 3B, the periodic transmission processing unit 17 is activated at intervals of 1 second, and transmits periodic data (health check data) at intervals of 4 seconds from the high-speed line (12A). It shows that the fixed-cycle data is transmitted at 12-second intervals from the line (12B).

That is, the fixed-cycle transmission processing unit 17 transmits fixed-cycle data from the high-speed line (line 12A) at intervals of 4 seconds, and otherwise, the control event transmission processing unit 18 is activated at intervals of 1 second. Further, a schedule is shown in which the periodic data is transmitted from the low speed line (line 12B) at intervals of 12 seconds and the control event transmission processing unit 18 is activated at intervals of 4 seconds. That is, in the transmission timing table for each line illustrated in FIG.
(1) When a high-speed line (line 12A) is selected by the line selection switch 111 0 seconds: Health check data is transmitted (control data is not transmitted).
1 second: The control event transmission processing unit 18 is activated.
2 seconds: The control event transmission processing unit 18 is activated.
3 seconds: The control event transmission processing unit 18 is activated.
4 seconds: Health check data is transmitted from the high-speed line (line 12A) (control data is not transmitted). Also, control data is not transmitted from the low speed line (line 12B).
(2) When the low-speed line (line 12B) is selected by the line selection switch 111 0 seconds: Health check data is transmitted (control data is not transmitted).
4 seconds: The control event transmission processing unit 18 is activated.
8 seconds: The control event transmission processing unit 18 is activated.
12 seconds: Health check data is transmitted from the low speed line (line 12B) (control data is not transmitted). Also, control data is not transmitted from the high-speed line (line 12A).
It is shown that the fixed-cycle transmission processing unit 17 operates according to the schedule.

  By doing in this way, the master station 1 executes the transmission process of the periodic data (health check data) and the control data according to the transmission capability of the high speed line (line 12A) and the low speed line (line 12B). Can do.

FIG. 4 is a flowchart showing a processing procedure of the transmission request interface of FIG. FIG. 5 is a diagram showing a message format created by the transmission request interface of FIG.
The processing procedure of the transmission request interface will be described using FIGS. 4 and 5 with reference to FIGS.

  The control processing unit 14 in FIG. 1 makes a transmission request via the transmission request interface 15. In response to this, the transmission request interface 15 first refers to the transmission buffer management table 19 and confirms the usage status of the transmission data buffer 16 (S41). Here, when there is no empty space in the transmission data buffer 16 (No in S42), the transmission BUSY is notified to the control processing unit 14 (S47).

  On the other hand, if there is an empty space in the transmission data buffer 16 (Yes in S42), the transmission request interface 15 creates transmission data (S43).

  Specifically, the transmission request interface 15 receives the transmission data received from the control processing unit 14 (destination station number, message ID, transmission sequence number acquired from the transmission sequence number management table 10, and a counter value generated from the current time ( Data including time stamp) and control setting value) is edited into a predefined message format.

  For example, according to the message format, the transmission request interface 15 sends a source station number, a destination station number, a transmission serial number, a transmission byte number, a message ID, a time stamp indicating the date and time when this data was created, and a control setting. Transmission data including a value is created (see FIG. 5).

Next, the transmission request interface 15 sets the transmission data edited in the message format in the empty space of the transmission data buffer 16 (S44), and updates the transmission buffer management table 19 based on the set transmission data (S45). . That is, for the management information in the transmission buffer management table 19 corresponding to the plane set in the transmission data buffer 16, the usage state is updated from empty to a transmission request (waiting for transmission). Further, the station number (destination station number), message ID, transmission sequence number, time stamp, etc. included in the transmission data set in the transmission data buffer 16 are written in the transmission buffer management table 19.
In this way, the transmission request interface 15 registers management information regarding the transmission data buffer 16 in the transmission buffer management table 19.

FIG. 6 is a flowchart showing a processing procedure of the control event transmission processing unit of FIG.
A processing procedure of the control event transmission processing unit 18 will be described using FIG. 6 with reference to FIGS.

  When the control event transmission processing unit 18 is activated by the periodic transmission processing unit 17, the control event transmission processing unit 18 determines whether or not there is a transmission request in the transmission request information of the transmission buffer management table 19 (S61). ).

  If there is a transmission request (Yes in S61), the control event transmission processing unit 18 acquires transmission data corresponding to the transmission request from the transmission data buffer 16 (S62), and sends it to the network transmission / reception unit 13. A transmission request is made (S63). When there are a plurality of transmission requests in S61, the control event transmission processing unit 18 requests the network transmission / reception unit 13 to transmit in order from transmission data with a higher priority.

  Here, transmission data for which the control event transmission processing unit 18 preferentially requests transmission to the network transmission / reception unit 13 is identified by an area (case number) of registration information in the transmission buffer management table 19. Details of the identification method at this time will be described later.

Then, the control event transmission processing unit 18 updates the use state of the transmission buffer in the management information of the transmission buffer management table 19 from the transmission waiting to the transmission request after the transmission request (S64), and the network transmission / reception unit 13 transmits the control event transmission. The transmission data requested to be transmitted from the processing unit 18 is transmitted, and it is awaited to be activated again.
In this way, the control event transmission processing unit 18 transmits control data.

  The transmission request from the control event transmission processing unit 18 to the network transmission / reception unit 13 is sent to the transmission timing table 11 (see FIG. 3B) and the line selected by the line selection switch 111 (111A to 111N). Based on.

For example, when the activation timing in S61 is the activation timing of the control event transmission processing unit 18 of the high-speed line (line 12A) in the transmission timing table 11, and the high-speed line (line 12A) is selected in the line selection switch 111A. The control event transmission processing unit 18 requests the network transmission / reception unit 13 to transmit via the high-speed line (line 12A).
On the other hand, when the low speed line (line 12B) is selected in the line selection switch 111A, the control event transmission processing unit 18 does not send a transmission request to the network transmission / reception unit 13.

Further, when the activation timing in S61 is the activation timing of the control event transmission processing unit 18 for the low speed line (line 12B) in the transmission timing table 11, and the low speed line (line 12B) is selected in the line selection switch 111A. The network transmission / reception unit 13 is requested to transmit via the low-speed line (line 12B).
On the other hand, when the high-speed line (line 12A) is selected in the line selection switch 111A, the control event transmission processing unit 18 does not send a transmission request to the network transmission / reception unit 13.

FIG. 7 is a diagram for explaining the operation of the transmission request interface and the control event transmission processing unit in FIG.
It is a figure explaining operation | movement of the transmission request interface 15 and the control event transmission process part 18 using FIG. 7, referring FIGS. 1-6.

  When the transmission request interface 15 registers management information in the transmission buffer management table 19, the transmission request interface 15 refers to the message ID of the transmission data and determines the use case of the management information. That is, for each message ID, the transmission request interface 15 holds a table indicating the range of use cases of the management information of the transmission data of the message ID, and refers to the message ID of the transmission data and this table. The management information related to the transmission data with low priority is registered in any case from the (N + 1) th case to the last case. By the way, high priority transmission data is data related to city gas supply district blocking control requests, data related to emergency control instructions such as city gas supply stop control requests, etc. Log data (log data in which the control history in the slave station 2 is recorded) and the like.

  When the control event transmission processing unit 18 searches the transmission buffer management table 19, it first searches the registration area (the Nth case from the top) of management information of transmission data with a high priority. Then, it is determined whether or not there is management information of transmission data to be transmitted by the control event transmission processing unit 18 in this registration area. When there is management information, transmission data is selected from the transmission data buffer 16 using the message ID described in the management information as a key, and a transmission request is sent to the network transmission / reception unit 13. At this time, when there are a plurality of management information in the registration area, transmission requests are made to the network transmission / reception unit 13 in order from transmission data having the smallest time stamp value.

  On the other hand, if there is no management information to be transmitted by the control event transmission processing unit 18 in the case from the first to the Nth case, the (N + 1) th and subsequent cases (general-level transmission data registration area) are searched. As in the case described above, when there is management information in this registration area, transmission data corresponding to the management information is transmitted. Further, when there are a plurality of management information in the registration area, the network transmission / reception unit 13 is requested to transmit in order from the transmission data having the smallest time stamp value.

  In this way, in the transmission buffer management table 19, by securing a case of registering management information of transmission data having a high priority, transmission data having a high priority such as an emergency control request is transmitted by a transmission rush of transmission data. The situation where management information cannot be registered can be avoided. In other words, the master station 1 preferentially and reliably transmits transmission data having a high priority to emergency control instructions such as a city gas supply district blocking control request and a city gas supply stop control request. be able to. In addition, ensuring the case of registering the management information of transmission data with high priority in this way is possible even when only the low-speed line (line 12B) is operated due to the failure of the communication device or the influence of maintenance work. This is particularly effective when it is desired to transmit transmission data with high priority to the slave station 2 reliably and preferentially.

  Note that the data transmission procedure from the slave station 2 (2A to 2N) to the master station 1 is the same as the data transmission procedure from the master station 1 to the slave station 2 (2A to 2N). Omitted.

  By doing so, even in the case where a dual redundant line is used in the supervisory control system, data loss due to mismatch in status recognition between the master system and the slave system between the data transmission side station and the reception side station is eliminated. . In addition, by performing transmission scheduling according to the transmission capabilities of both lines 12 (lines 12A and 12B) using the transmission timing tables 11 and 21, the line load can be made uniform and stable monitoring control can be performed. Can be realized.

  The master station 1 according to the present embodiment can be realized by a program for executing the processing as described above, and the slave station 2 can be realized by a program for executing the processing as described above. Further, these programs can be provided by being stored in a computer-readable storage medium. It is also possible to provide the program through a network.

  In the above-described embodiment, the case where the present invention is applied to a monitoring system for city gas supply has been described as an example. However, if the master station 1 is a monitoring system that monitors the slave station 2 using a communication line, It can also be applied to monitoring systems other than city gas supply.

It is the block diagram which expanded and showed the function of the structure of the monitoring control system of this Embodiment. FIG. 2 is a block diagram showing a functional development of the configuration of the slave station in FIG. 1. (A) is a flowchart illustrating a processing procedure of a fixed-cycle transmission processing unit of the master station in FIG. 1, and (b) is a diagram illustrating a data transmission timing table for each line of the master station in FIG. It is a flowchart which shows the process sequence of the transmission request interface of FIG. It is the figure which showed the message | telegram format which the transmission request interface of FIG. 1 produces. It is the flowchart which showed the process sequence of the control event transmission process part of FIG. It is a figure explaining the selection method of the transmission data by the priority in this Embodiment.

Explanation of symbols

1 Master station 2 (2A to 2N) Slave station 10,20 Transmission sequence number management table 11,21 Line-specific data transmission timing table (transmission timing table)
12 (12A, B) line 13,23 network transmission / reception unit 14,24 control processing unit 15,25 transmission request interface 16,26 transmission data buffer 17,27 fixed period transmission processing unit (transmission processing unit)
18, 28 Control event transmission processing unit 19, 29 Transmission buffer management table 111 (111A to 111N), 211 Line selection switch

Claims (7)

In order to perform monitoring control for one or more process equipment bases that are distributed, a monitoring device that transmits and receives various data using each of the process equipment bases and a dual redundant line,
A control event transmission processing unit for transmitting control data related to a control event generated in the monitoring device;
For each line constituting the dual redundant line, a transmission timing of health check data to be transmitted to the process equipment base, and a data transmission timing table for each line indicating the start timing of the control event transmission processing unit,
According to the timing shown in the data transmission timing table for each line, the health check data is transmitted from both lines of the dual redundant line, and a transmission processing unit for starting the control event transmission processing unit,
In the control event transmission processing unit, comprising a line selection unit for selecting one of the double redundant lines for each process facility base, the line used when transmitting the control data,
The monitoring apparatus, wherein the control event transmission processing unit transmits the control data to the process facility bases using a line selected by the line selection unit. The monitoring device, a transmission buffer management table related to a buffer of transmission data to the process equipment base,
Management table registration means for registering management information relating to the buffer of the transmission data in the transmission buffer management table;
The management table registration means determines the priority of the transmission data according to the type of the transmission data, determines a registration area in the transmission buffer management table for the transmission data according to the determined priority,
The control event transmission processing unit searches the management information of the transmission data in order from the area where the management information related to the transmission data with a high priority is registered in the transmission buffer management table, and the searched management information The monitoring device according to claim 1, wherein the corresponding transmission data is transmitted.   The said line selection part selects either one of the said dual redundant line based on the instruction information input via the input / output interface of the said monitoring apparatus, The Claim 1 or Claim 2 characterized by the above-mentioned. Monitoring device. A process equipment base that transmits and receives various data to the monitoring device using a double redundant line,
A control event transmission processing unit for transmitting response data to the control data from the monitoring device;
For each line that constitutes the double redundant line, a data transmission timing table for each line indicating the transmission timing of the measurement data measured at the process equipment base, and the start timing of the control event transmission processing unit,
According to the timing shown in the data transmission timing table for each line, the measurement data is transmitted from both lines of the dual redundant line, and a transmission processing unit that activates the control event transmission processing unit,
In the control event transmission processing unit, a line used when transmitting the response data includes a line selection unit that selects any one of the dual redundant lines,
The process facility base, wherein the control event transmission processing unit transmits the response data to the monitoring device using the line selected by the line selection unit. The process facility base includes a transmission buffer management table relating to a buffer of transmission data to the monitoring device, and
Management table registration means for registering management information relating to the buffer of the transmission data in the transmission buffer management table;
The management table registration means determines a registration area of the transmission data in the transmission buffer management table according to the priority of the transmission data,
The control event transmission processing unit searches the management information of the transmission data in order from the area where the management information related to the transmission data with a high priority is registered in the transmission buffer management table, and the searched management information 5. The process equipment base according to claim 4, wherein the corresponding transmission data is transmitted.   5. The line selection unit according to claim 4, wherein the line selection unit selects one of the dual redundant lines based on instruction information input via an input / output interface of the process facility base. 5. Process equipment base according to 5.   A monitoring control system comprising the monitoring device according to any one of claims 1 to 3 and the process facility base according to any one of claims 4 to 6.

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