JPH11242507A - Plant control system - Google Patents

Abstract

(57) [Summary] [Problem] To provide an early solution to a trouble caused by a failure of a start / operation interlock condition which occurs at the time of start / operation. An EWS 3, an operation monitoring device 4, and a plurality of PLCs 2a, 2b, 2c are connected to a process LAN 1. Furthermore, the EWS 3 and the operation monitoring device 4 are a general-purpose LA.
The client / server system is also connected by N5. The EWS 3 incorporates a control sequence program creation / editing unit 13 and an online monitoring unit 11 for monitoring the execution state of the control sequence program. The first-off interlock monitoring program is executed in each PLC, thereby monitoring the startup / operation interlock sequence and issuing an alarm notification when the startup / operation interlock is turned off due to occurrence of an abnormality. The state of the interlock condition at that time is scanned and transmitted to the operation monitoring device 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plant control system for controlling steel, petrochemical and general industrial plants.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 8, a plant control system for controlling steel, petrochemical and general industrial plants includes a plurality of programmable controllers (hereinafter referred to as a process LAN) 1 by a process local area network (hereinafter referred to as a process LAN). (Hereinafter referred to as PLC) 2a, 2
b, 2c, an engineering workstation (hereinafter, referred to as EWS) 3, and an operation monitoring device 4 are connected and configured. Further, the EWS 3 and the operation monitoring device 4 are also connected by a general-purpose local area network (hereinafter, referred to as a general-purpose LAN) 5 such as an Ethernet network, and constitute a client / server system.

[0003] A control program for controlling the PLC is prepared in a problem-oriented description language (POL) such as a ladder, and includes not only a sequence relating to plant operation but also a sequence.
It also has a start / operation interlock sequence for stopping the operation of the plant equipment when any abnormality occurs during the activation / operation of the plant equipment.

[0004]

However, in the conventional plant control system, the language used for the PLC control program is difficult for general users to understand, and some abnormality occurs during the start-up and operation of the plant equipment. When it occurred and the operation of the plant equipment was stopped, a huge amount of programs had to be analyzed in order to investigate the cause, and abundant experience and specialized knowledge were required. In addition, as described above, since the configuration and language of the control program are complicated and difficult to understand, a large amount of cost is required to create a new control program during system maintenance.

Accordingly, the present invention has been made in view of the above problems, and has been made in view of the above problems. When the operation of plant equipment is stopped, the cause thereof is quickly and accurately investigated, and a process control system capable of automatically creating and editing a control program which is easy for a user to understand. The purpose is to provide

[0006]

In order to achieve the above object, the present invention provides a plant in which a plurality of programmable controllers, an engineering work station, and an operation monitoring device are connected via a network and have a number of controlled devices. In a plant control system that controls
The engineering workstation creates and edits a control program used in the programmable controller with a graphic symbol, and supplies the created and edited control program to the programmable controller.
An execution state of the control program of an arbitrary programmable controller is displayed by the graphic symbol, and the displayed graphic symbol is supplied to the operation monitoring device in response to a request from the operation monitoring device, and a plurality of the programmable controllers are provided. Each of the programmable controllers controls the controlled device according to a control program supplied from the engineering workstation, and outputs data relating to an operation stop state when an abnormality occurs in the controlled device and operation is stopped. The operation monitoring device monitors the programmable controller and issues an alarm based on the data output from the programmable controller.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the drawings, the same components as those of the related art are denoted by the same reference numerals, and description thereof is omitted.

First, a first embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, in the present embodiment, a plurality of PLCs 2
a, 2b, 2c, the EWS 3, and the operation monitoring device 4 are connected and configured. Further, the EWS 3 and the operation monitoring device 4 are also connected by a general-purpose LAN 5 such as Ethernet, and constitute a client / server system.

The EWS 3 is a computer having a keyboard and a mouse (both not shown), a mass storage device, a display and a main body.
Various operations are performed by software to be incorporated. In the present embodiment, a functional configuration for realizing the function as an online monitor will be described.

FIG. 2 is a block diagram showing the configuration of the EWS 3 shown in FIG. 1 and a diagram showing an example of a monitor screen displayed on its display. The EWS 3 is a computer that includes a keyboard and a pointing device such as a mouse (not shown), and includes a mass storage device, a display, and a main unit, and performs various operations according to a software program incorporated therein. Here, a functional configuration for realizing the function as the online monitor device of the present invention will be described.

The monitor unit 11 transmits and receives process data (message transmission ml, scan transmission m2) to and from the plurality of PLCs 2a, 2b, 2c and the operation monitoring device 4 through the process LAN 1 according to the installed program. As shown in FIG. 2, various screens are displayed in a multi-window format, and input operations using a keyboard and a mouse are also accepted.

The device information file 15 includes PLCs 2a,
b, 2c, process LAN / network IDs, information on process devices to be controlled, all PLCs 2a, 2c,
The control signal names used in b, 2c and the control program of the operation monitoring device 4, and the addresses and cross-reference information used in the control signal names are registered and managed in a unified manner.

The program creating / editing unit 13 includes a PLC 2
a, 2b, and 2c, which are the control specifications of the diagram format shown in FIG. 3 and the ladder sequence shown in FIG. 4, can be created by using the monitor / display screen of FIG. It is registered in the specification file 16. Also, the created control sequence is used for the PLC 2a, 2b,
2c is converted into an executable load module and downloaded to an arbitrary PLC, for example, a program storage memory P of the PLC 2a. The PLCs 2a, 2b, and 2c are connected to respective control target devices via input / output devices (not shown), and perform automatic control and control of the control target devices according to a control sequence program incorporated in a program area P of an internal memory. The operation result of the sequence is written in the data area D.

The PLCs 2a, 2b and 2c are connected to the EWS3
And an operation result written in an arbitrary data area in response to a monitor request from the operation monitoring device 4 or the like.

The first-off interlock monitoring program shown in FIG. 4 operates in the same manner as the other control sequences, but FIG. 43 shows that the interlock i1 is turned off because one of the interlock conditions fl,..., F8 is not satisfied. .., F8 at the same time as the alarm notification ml.

As shown in FIG. 5, the operation monitoring device 4 sends and receives various process data (message transmission ml, scan transmission m2) from the PLCs 2a, 2b, 2c via the process LAN 1. If the received process data includes the alarm notification ml, the content is displayed on the display 12 to notify the operator (operator). In addition, the alarm notification ml is first-off
If it is from the interlock monitoring program, the operation monitoring device 4 sends the alarm notification ml and the PLC 2a, 2
On the basis of the states of the interlock conditions fl,..., f8 written in the scan transmission data area D by b and 2c, an online display request m3 is transmitted to the EWS 3 to display the interlock sequence that has been turned off first on the online monitor.

EWS receiving online display request m3
3 searches the diagram specification file 16 for a corresponding interlock sequence based on the device information file 15, and displays an online display screen of the interlock sequence on the operation monitoring device 4.

Therefore, according to the present embodiment, by monitoring the interlock sequence by the PLC itself,
The control sequence in which the abnormality has occurred can be easily found.

Next, a second embodiment of the present invention will be described with reference to FIGS. 3, 4 and 6. FIG.

As shown in FIG. 6, this embodiment employs a first
The interlock sequence program monitoring device according to the present embodiment is characterized in that the interlock sequence program monitoring device further includes a program generation unit 17 that automatically generates a first-off interlock monitoring program from the generated interlock sequence program.

That is, from the interlock sequence program shown in FIG. 3 created by the program creating / editing unit 13, the program creating unit 17
The t-off interlock monitoring program is registered in the diagram specification file 16 together with information indicating the relationship with the interlock sequence program of the generation source. At this time, information such as signal names automatically performed is registered in the apparatus coasting information file 15, and the interlock sequence program of the generation source is converted into an arbitrary PLC execution program.
When downloaded, this automatically generated firs
The t-off interlock monitoring program is also converted into an execution program and downloaded.

As described above, according to the present embodiment, fir
Since the st-off interlock monitoring program is automatically generated when the interlock sequence program is created, not only can the control sequence be saved, but also the first-off interlock monitoring program can be prevented from being omitted and a certain quality can be prevented. A first-off interlock monitoring program can be easily created.

Next, a third embodiment of the present invention will be described.
A description will be given based on FIG.

In this embodiment, the interlock sequence program monitoring device of the first embodiment further includes an interlock condition and an interlock signal name in the interlock sequence program displayed on the online monitor screen. The cross-reference information x 1 of the input / output destination is displayed, and the interlock sequence program displayed on the online monitor screen is clicked by a pointing device such as a mouse while the online monitor is being executed. It is characterized in that the online monitor display can be switched to a diagram specification describing the control sequence indicated by the reference information.

FIG. 7 shows a monitor device according to this embodiment.
And a control sequence description program in which the signal names are described based on information related to the signal names included in the device information file 15 when the interlock sequence shown in FIG. A code identifying the name is automatically added to the created interlock sequence and associated control sequence.

When a request for switching the online monitor display based on the cross-reference information is made during online monitoring, the monitor device is requested to display the online monitor based on the requested cross-reference information xl. Switch to the diagram specification that describes the control sequence.

As described above, according to the present embodiment, the control sequence of the output destination of the interlock condition turned off first can be easily searched from a huge amount of control sequences, and the cause of the turn off first can be determined. The control sequence can be found retroactively.

[0029]

As described above, according to the present invention, when the operation of the plant equipment is stopped, the cause can be quickly and accurately investigated, and a control program that can be easily understood by the user can be automatically created and edited. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing an online monitor screen displayed on a display of the monitor device in the embodiment shown in FIG.

FIG. 3 is a diagram showing an interlock sequence described in a diagram specification in the embodiment shown in FIG. 1;

FIG. 4 is a diagram showing a first-level control in the embodiment shown in FIG.
It is a figure which shows an off interlock monitoring program.

FIG. 5 is a block diagram illustrating an operation between the PLC and the operation monitoring device when an abnormality is detected by the first-off interlock monitoring program illustrated in FIG. 4;

FIG. 6 is a schematic configuration diagram showing a second embodiment of the present invention.

FIG. 7 is a schematic configuration diagram showing a third embodiment of the present invention.

FIG. 8 is a schematic configuration diagram showing a conventional general process control system.

[Explanation of symbols]

 Reference Signs List 1 process LAN 2a, 2b, 2c PLC 3 EWS 4 operation monitoring device 5 general-purpose LAN 11 monitor unit 12 display 13 program creation / editing unit 15 device information file 16 diagram specification file 17 program generation unit

Claims (1)

[Claims] A plurality of programmable controllers;
In a plant control system in which an engineering work station and an operation monitoring device are connected via a network to control a plant having a large number of controlled devices, the engineering workstation includes a control symbol used in the programmable controller as a graphic symbol. The control program created and edited is supplied to the programmable controller, the execution state of the control program of any programmable controller is displayed by the graphic symbol, and in response to a request from the operation monitoring device. The displayed graphic symbol is supplied to the operation monitoring device, the programmable controller is provided in plurality, and each of the programmable controllers is supplied from the engineering workstation. Controlling the controlled device in accordance with the control program and outputting data relating to the operation stop state when an abnormality occurs in the controlled device and stopping the operation, the operation monitoring device monitors the programmable controller, and outputs the data from the programmable controller. A plant control system that issues an alarm based on the output data.