JPH06217376A - Remote supervisory control system - Google Patents

Abstract

PURPOSE:To improve the reliability of supervision of a plant by backing up a private line tying a remote plant and a central supervisory room with a general telephone line so as to prevent defect of data. CONSTITUTION:A general telephone line 4 is connected between a central supervisory room 1 and a remote plant supervisory controller 2 in addition to a private data transmission line 3. When a detection section of the plant supervisory equipment 2 detects the occurrence of a fault in the transmission system of the private line 3, a changeover means is used to select telephone network communication to maintain a transmission function of plant process data and collected data are sent to the central supervisory room upon a transmission request from the central supervisory room or periodically. Thus, the data transmission function is maintained and missing of process data is prevented and the reliability of plant supervisory control is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distant monitoring and control system having a dual line for data transmission and a general telephone line for backup.

[0002]

2. Description of the Related Art In general, a distant monitoring control system is generally used in plants scattered over a wide area such as water and sewage systems, gas plants, etc., and its data transmission path is provided by NTT.
Private line or private line is used.

[0003]

However, in such a conventional distant monitoring control system, only a dedicated line is used for a data transmission line, and another transmission line is installed in parallel for backup. Therefore, once a failure occurs in the data transmission line, it only informs the central monitoring room of an abnormality in the data transmission line, it cannot transmit process information at all, and a failure occurs as a countermeasure for the abnormality. It is necessary to dispatch a technician to the site of the plant and manually operate the plant while communicating with the central monitoring room using a communication device such as a telephone or a radio. However, there is a problem that it requires a large number of operators who are familiar with non-plants and that it takes time to find the cause of a failure.

Further, while the data transmission line has a failure, it is impossible to collect process information data, and measurement data important for operation and maintenance of the plant is temporarily lost, which results in operation and maintenance of the plant. There was also a problem that it would cause a big obstacle to the.

The present invention has been made in view of the above-mentioned conventional problems. Even if a failure occurs in a dedicated data transmission line, the process data collection of the plant and the transmission to the central monitoring room are used as a backup. It is an object of the present invention to provide a remote monitoring and control system that can be continuously performed by using a general telephone line and that can reduce a trouble caused in operation and maintenance of a plant.

Further, according to the present invention, when a failure occurs in the dedicated data transmission line, the test program of the plant monitoring control device is executed through the backup general telephone line, and the failure diagnosis of the process monitoring control device is performed from the result. , Analysis can be performed, the work of pursuing the cause of failure can be performed to some extent on the side of the central monitoring room, the chances of dispatching skilled operators to the field can be reduced, and the number of engineers preparing for maintenance can be reduced accordingly. It is an object of the present invention to provide a remote monitoring and control system capable of performing

[0007]

According to a first aspect of the present invention, there is provided a distant supervisory control system in which a dedicated line is used as a data transmission path and a central supervisory room and a distant plant supervisory controller are connected to each other. A general telephone line for backup is connected between the monitoring room and a remote plant monitoring control device, and the plant monitoring control device side collects and saves plant process values periodically and a dedicated line. Detection of the occurrence of a communication failure, the communication switching unit that switches from the leased line communication to the telephone network communication, and the data stored in the data collection unit is periodically monitored when the communication switching unit is switching to the backup telephone network communication. And a data transmission means for transmitting data in response to a transmission request from the central monitoring room.

According to a second aspect of the present invention, in the above distant supervisory control system, the plant supervisory controller further executes a test program for performing fault diagnosis and analysis of the plant supervisory control function, and the result is transmitted to the data transmission. The test program execution processing means to be delivered to the means is provided.

[0009]

In the remote monitoring and control system according to the invention of claim 1,
If a general telephone line for backup is connected between the central monitoring room and the plant monitoring and control device at a distant place in addition to the data transmission line consisting of a dedicated line, and a failure occurs in the dedicated data transmission line The communication switching means detects the occurrence of a communication failure in the leased line and switches from the leased line communication to the telephone network communication to maintain the plant process data transmission function, and the data transmission means collects the data collected by the data collection means. It is transmitted to the central monitoring room periodically or in response to a transmission request from the central monitoring room.

In this way, even if a failure occurs in the leased line, the data transmission function between the central monitoring room and the plant monitoring control device at a distant place can be maintained through a general telephone line, and a part of the process data may be lost. It is possible to prevent and improve the reliability of plant monitoring control.

In the remote monitoring control system according to the second aspect of the present invention, further, when a failure occurs in the dedicated data transmission path, the central monitoring room side diagnoses and analyzes the failure in the target plant monitoring control device. The test program for execution is executed, and the execution result is transmitted to the central monitoring room side through the general telephone line by the data transmission means, so that the cause of the failure can be investigated to some extent while staying in the central monitoring room side, and then go to the site. Make sure that repair work can be performed efficiently by identifying repair points and preparing necessary replacement equipment.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows the system configuration of an embodiment of the present invention. As shown in FIG. 1, in the distant monitoring control system of this embodiment, a central monitoring room 1 and a plurality of distant plant monitoring control devices 2 are duplicated by a dedicated line 3 and a general telephone line 4 for backup. It is a configuration connected via a line. The central monitoring room 1 is connected with a central computer 5 for controlling the entire plant monitoring and control, a CRT 6 and a printer 7 as its peripheral devices, for modulating and demodulating a signal to a communication line as a data transmission means. Modems 8 and 9 are connected.

Each of the plant supervisory control devices 2 for supervising and controlling a distant plant has communication lines 3 and 4.
Modems 10 and 11 for modulating and demodulating signals to and from
Is installed as a data transmission means.

FIG. 2 shows a detailed configuration of the plant monitoring control device 2 (the central computer 5 in the central monitoring room 1 has almost the same function). The plant monitoring control device 2 has a normal remote monitoring control function. As a circuit in charge of the process, a process input / output control unit 12 for the plant, a process input / output data file 13, a data transmission / reception control circuit 14, and an arithmetic unit 15 for performing arithmetic processing are provided.

A process data storage unit 16 for storing various process values and alarm set values as a circuit responsible for the communication backup function of the leased line 3 and a fault detection unit for detecting an abnormal fault in the transmission system on the leased line 3 side. 17, a command processing unit 18 that sorts out and determines requests sent from the central monitoring room 1, and an R that stores failure status and various error information
AS (Reliability Availability)
ty Serviceability) information storage unit 19
And a time management unit 20 and a test program execution processing unit 2 that executes a test program for confirming a failure state.
1 and an NCU control unit 22 that performs data communication control processing for telephone network control and protocol and connection control.

The modem 11 for the general telephone line 4 for backup has an AA type NC having an automatic dialing function.
U-modem is used.

Next, the operation of the remote monitoring and control system having the above configuration will be described.

In the normal state, control of the plant is performed by connecting the central monitoring room 1 and the distant plant monitoring control device 2 through a dedicated line 3, and an analog input (AI) card 12A of the process input / output processing unit 12 and a digital input. (D
I) Various signals of the process are input through the card 12B and the pulse input (PI) card, stored in the process input / output data file 13, and transmitted from the modem 10 to the central monitoring room 1 through the leased line 3 by the data transmission / reception control circuit 14. It Further, the command signal sent from the central monitoring room 1 through the dedicated line 3 is demodulated by the modem 10, and the process input / output data file 1 is sent through the data transmission / reception control circuit 14.
3D, digital output (DO) card 12D,
It is output to the plant through the analog output (AO) card 12E and the required operations are performed.

If the transmission line of the leased line 3 for executing such a normal remote monitoring control function cannot be transmitted due to some failure, communication backup and failure prevention, maintenance and failure diagnosis of the entire remote monitoring control function, The transmission system is switched to the general telephone line 4 and the NCU modem 11 for it for analysis communication. This communication backup operation will be described.

First, when the following transmission line fault of the dedicated line 3 is detected, the fault detection unit 17 judges the condition and automatically switches the transmission line to the general telephone line 4.

1) The disconnection of the leased line 3 continues for several seconds or more,
If it does not return until the outgoing command is output.

2) When erroneous transmission occurs in two or more cycles due to the problem of the S / N ratio of the dedicated line 3.

The failure determination parameter is variable and should be changed according to the system configuration.

In this way, when the fault detector 17 detects the occurrence of a fault in the transmission line of the leased line 3, the automatic transmission function shown in FIG. 3 is activated. That is, the condition for generating the automatic transmission request signal 16H in the case where the device itself is the calling side and is transmitting is that the process state change monitoring unit 16F has an output when the failure detection unit 17 rises or the failure condition continues, or a failure occurs. This is a case where the alarm value deviation monitoring unit 16G for the measured value outputs while the state continues. Also, every time the hour management unit 20 makes a request on the hour, a connection request is issued to the NCU control unit 22 and the transmission procedure is started.

As shown in FIG. 3, the process data storage unit 16 captures data from the process input / output data file 13 and stores instantaneous value collection data 16A for storing analog input and digital input at each scan cycle and previous scan data. Instantaneous value save data 16B to save, fixed value save data 16C to move from the instantaneous value save data 16B every hour on the hour, and save as hourly / daily report data, instantaneous value collection at fixed intervals, for example, every few seconds to several minutes The real-time collected data 16D that saves the data 16A, the measurement value alarm set value 16E that sets and saves the alarm value of each analog input, and the like are saved. The real-time collected data 16D stores the instantaneous value collected data 16A in each predetermined cycle, and the cycle can be selected from several seconds to several minutes. This real-time collected data 16D is a valuable data for process analysis and operation support as well as preventing data missing when a failure occurs in the transmission system of the dedicated line 3.

Therefore, the process state change monitoring unit 16F compares the instantaneous value collection data 16A, which is the current scan data, with the instantaneous value storage data 16B, which is the previous scan data, and changes the state of the designated digital input or the analog value. Deviation of the rate of change is detected, and if the failure continues, the automatic transmission request signal 16H is generated to generate the instantaneous value collection data 16
A is sent to the NCU control unit 22 and transmitted to the central monitoring room 1 side through the general telephone line 4. In addition, the scheduled value save data 1
In response to the request from the time management unit 20, the 6C sends it to the NCU control unit 22 and transmits it to the central monitoring room 1. Further, the measured value alarm set value 16E is an alarm set value of analog values such as water level, pressure, and flow rate of the plant.
Is compared with the alarm value deviation monitoring unit 16G, and if there is a deviation, an automatic transmission request signal 16H is generated, the instantaneous value collection data 16A is sent to the NCU control unit 22, and the general telephone line 4
Through the central monitoring room 1 side.

In the case where the central monitoring room 1 side detects an abnormal failure in the transmission line of the ordinary leased line 3 and tries to switch to the general telephone line 4 for backup to continue data transmission, Operate.

The signal sent from the central monitoring room 1 through the general telephone line 4 and the NCU modem 11 is the NCU control unit 2.
2, the NCU control unit 22 performs an incoming call connection process and a data communication process in response to a request from the calling side, and sends the contents to the command processing unit 18.

As shown in FIG. 4, the command processing section 18 sorts out and judges the commands that have been sent, and requests each of the associated blocks. For example, the request for the backup data request 18A includes a transmission request for the time-save data 16C such as hourly and daily reports,
Real-time collection data 1 saved and stored at fixed intervals
There is a request for transmission of 6D plant history data and a request for transmission of measured value alarm set value 16E, and these are transmitted individually or collectively from the NCU control unit 22 to the central monitoring room 1 side through the general telephone line 4. . If the request is the time adjustment request 18B, the basic clock of the time management unit 20 is corrected. In this case, the content including the date will be changed to the requested content.

In this way, when a failure occurs in the transmission line on the side of the leased line 3, if it is detected by the distant plant monitoring control device 2 side, the transmission line is automatically transferred to the general telephone line 4 side for backup. To switch to the central monitoring room 1 by automatically dialing with the NCU modem 11 when a fault is detected, when the process status changes suddenly, or when the alarm value deviates, and also every hour on the hour. It is transmitted to the first side through the general telephone line 4 for backup. If the central monitoring room 1 side detects a failure of the leased line 3, a data transmission request is made through the backup general telephone line 4, and the necessary data is transmitted from the plant monitoring control device 2 side through the general telephone line 4. In this way, data transmission is continuously performed even when a failure occurs in the transmission system of the leased line 3, information required for operation is efficiently transmitted in a timely manner, and reliability and safety of plant monitoring control are improved. , Reduce the burden on operators.

As shown in FIG. 5, the remote monitoring control system of this embodiment is also provided with a failure diagnosis and analysis function, and the NCU control section 22 is provided from the central monitoring room 1 side through the general telephone line 4 and the NCU modem 11. The signal sent to
The command processing unit 18 sorts and discriminates and performs request processing of a remote RAS information transmission request 18C and a test program execution request 18D from the central monitoring room 1 side.

First, the RAS information storage unit 19 has line failure information 19A, system state information 19B, and event trace 1
9C, system information 19D, and a test program execution result 19E when the test program is executed are stored.

The line fault information 19A is the fault state and the number of occurrences of the transmission line of the leased line 3 and the error information and the number of times of the communication system including each communication card, and the system state information 19B is the system monitoring of each module. And the self-diagnosis result data. Further, the event trace 19C is data including the contents of power-on, calling and receiving, and time information of failure history, and the system information 19D is hardware configuration and software version N that configures the system.
o. And the data of optional functions. And, when the remote monitoring and control system fails, it is possible to prepare repair parts for failure repair just by utilizing these RAS information without investigating the system-specific instruction manual and configuration table. It has become.

The test program executed by the test program execution processing section 21 is RAS information reset 21A, R
AM test 21B, ROM test 21C, I / O port test 21D, communication loopback test 21E, watchdog timer (WDT) operation test 21F, and initialization (I
NZ) Request 21G.

The RAS information reset 21A is the line failure information 19A and the system state information 1 of the RAS information storage unit 19.
9B is a program for resetting the event trace 19C and the event trace 19C, and is for grasping the frequency of newly occurring faults and various errors by resetting past error counters and fault histories.

The RAM test 21B is a program for performing a writing / reading test of the RAM memory, and is capable of performing automatic full range designation and manual range designation. Further, the ROM test 21C collates the checksum value previously written at the time of writing the ROM memory with the checksum value calculated by itself, and confirms whether or not the contents of the ROM memory have changed from the initially written value. . The I / O port test 21D is a program for testing analog input / output and digital input / output, and the communication loopback test 21E is a program for executing loopback test including the transmission system of the dedicated line 3 shown in FIGS. The return point can be tested not only at the data transmission / reception control circuit 14 of the own station and the modem 10 but also at the same point of the partner station, and the transmission data and the reception data are collated. WDT operation test 21F is WDT
It is a program that checks the operation check of the circuit.
The NZ request 21G is a program for initializing the arithmetic unit 15 shown in FIG.

Therefore, if the test program activation request 18D is discriminated in the command from the central monitoring room 1 processed by the command processing unit 18, the test program execution processing unit 21 executes these test programs, and the execution result thereof. Is stored in the RAS information storage unit 19 as the test program execution result 19E and automatically transmitted from the NCU modem 11 and the general telephone line 4 to the central monitoring room 1 side through the NCU control unit 22.

In this way, when a failure occurs in the transmission line of the leased line 3, the RA is automatically sent from the plant monitoring controller 2 or in response to a transmission request from the central monitoring room 1.
By transmitting the S information to the central monitoring room 1 side through the general telephone line 4, and also automatically transmitting the result of executing the test program as necessary, it is possible to prevent missing data and to perform failure diagnosis and analysis. Even the central monitoring room side can easily perform it, it is possible to grasp the location of the failure and its cause in advance before going to a distant site, and make sufficient preparations such as necessary countermeasures, which is efficient Fault recovery is possible.

The present invention is not limited to the above-mentioned embodiment. In the invention of claim 1, the plant is used when a failure occurs in the transmission line of the leased line even if the failure diagnosis function is not provided. If the bidirectional transmission of the process data, the operation command signal and the like can be continuously performed through the backup general telephone line, the configuration is not limited.

Further, as the general telephone line, an ordinary public telephone line or integrated digital communication line (ISDN) can be used.

[0042]

As described above, according to the invention of claim 1,
If a backup general telephone line is connected between the central monitoring room and a distant plant monitoring and control device in addition to a data transmission line consisting of a dedicated line, and a failure occurs in the dedicated data transmission line The communication switching means detects the occurrence of a communication failure in the leased line and switches from the leased line communication to the telephone network communication to maintain the plant process data transmission function, and the data transmission means collects the data collected by the data collection means. Transmission is made to the central monitoring room on a regular basis or in response to a transmission request from the central monitoring room, so even if a failure occurs in the leased line, there will be a gap between the central monitoring room and the plant monitoring control device at a remote location. The data transmission function can be maintained through a general telephone line, the loss of process data can be prevented, and the reliability of plan monitoring control can be improved.

According to the second aspect of the present invention, when a failure occurs in the dedicated data transmission line, a test for performing failure diagnosis and analysis from the central monitoring room side to the target plant monitoring control device. Since the program is executed and the execution result is transmitted to the central monitoring room side through the general telephone line by the data transmission means, it becomes possible to investigate the cause of the failure to some extent while staying in the central monitoring room side. Before going to the site, it is possible to identify repair points and prepare necessary replacement equipment, so that failure recovery work can be performed efficiently.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an embodiment common to the inventions of claims 1 and 2. FIG.

FIG. 2 is a functional block diagram showing a configuration of a plant monitoring control device in the above embodiment.

FIG. 3 is a functional block diagram showing an automatic transmission operation of process data in the above embodiment.

FIG. 4 is a functional block diagram showing a process data transmission operation in response to a program data request from the central monitoring room side in the above embodiment.

FIG. 5 is a functional block diagram showing a transmission operation of RAS information and a test program execution result in the above embodiment.

[Explanation of symbols]

 1 Central monitoring room 2 Plant monitoring and control device 3 Private line 4 General telephone line 5 Central computer 6 CRT 7 Printer (PRT) 8 Modem 9 NCU modem 10 Modem 11 NCU modem 12 Process input / output control unit 13 Process input / output data file 14 Data Transmission / reception control circuit 15 Calculation unit 16 Process data storage unit 17 Failure detection unit 18 Command processing unit 19 RAS information storage unit 20 Time management unit 21 Test program execution processing unit

Claims (2)

[Claims] 1. A far-distance monitoring control system configured by connecting a central monitoring room and a distant plant monitoring control device by using a dedicated line as a data transmission path, wherein the central monitoring room and the distant plant monitoring control device are connected to each other. Connect a general telephone line for backup between, the plant monitoring control device side, data collection means for periodically collecting and storing the process values of the plant, and detecting the occurrence of communication failure of the dedicated line, Communication switching means for switching from leased line communication to telephone network communication, and when the communication switching means is switching to backup telephone network communication, periodically transmits the data stored in the data collecting means, or A distant monitoring control system comprising: a data transmission means for transmitting in response to a transmission request from the central monitoring room. 2. The distant monitoring control system according to claim 1, wherein the plant monitoring control device further executes a test program for performing fault diagnosis and analysis of the plant monitoring control function, and the result is used as the data. A remote monitoring and control system comprising a test program execution processing means to be transmitted to a transmission means.