AU737646B2 - Plant operating and monitoring system, and plant operating and monitoring method - Google Patents

Description

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION NAME OF APPLICANT(S): Hitachi, Ltd. AND Hitachi Information Control Systems Inc.

ADDRESS FOR SERVICE: DAVIES COLLISON CAVE Patent Attorneys 1 Little Collins Street, Melbourne, 3000.

INVENTION TITLE: Plant operating and monitoring system, and plant operating and monitoring method The following statement is a full description of this invention, including the best method of performing it known to me/us:r r BACKGROUND OF THE INVENTION The present invention relates to a plant operating and monitoring system, and a plant operating and monitoring method, in which the operational state of a plant is monitored 10 by displaying a trend graph of the process signals related plant components on a display device such as a CRT display device.

As disclosed, for example, in Japanese Patent Application Laid-Open Hei 9-237117, a trend graph of process variables (including control signals of a plant) is generally displayed on a display device to continuously monitor the operational states of the plant. By displaying the trend graph of the process variables related to plant components, it is easy to understand the history of changes from the past up to the present time and the future trend, of each process variable, and to grasp the response changes of corresponding process variables due to the operations of a plant component.

Further, Japanese Patent Application Laid-Open Hei 5-88744 discloses a technique in that it is possible to switch the displayed picture between a picture for displaying process variables with bar graphs and a picture for displaying changes of process variables as trend curves.

Also, the trend graph of process variables and a plant-component actuator-display picture are usually displayed on a display device in order to operate the plant while monitoring the trend graph.

The following are methods of displaying both the trend graph and the plant-component actuator (hereafter referred to as simply component actuator or actuator)-display picture 10 on the same display device.

oOO• A plurality of actuator-display pictures are S..classified into groups in advance, and a window picture of trend graph is superimposed and displayed on an actuator-display picture by operating one of the buttons displayed on a display device after one of the groups of the actuator-display pictures is displayed.

One of the groups of actuator-display pictures and the corresponding trend graph are retrieved, and both the retrieved actuator-display picture and corresponding trend graph are integrated and displayed.

One of the actuator-display pictures is displayed by designating one of the plant components in a plant schematic diagram displayed on a displaying device, and a trend graph corresponding to the displayed actuator-display picture (corresponding to the designated plant component) P OPERW An 325629)pcil ndndlm29AY5A) -3is further displayed.

The method is disclosed, for example, in Japanese Patent Application Laid-Open Hei 8-272436.

To monitor the operation of a plant, a trend graph of process variables is usually displayed on a display device.

Moreover, a trend graph of a plurality of process signals is simultaneously displayed.

If the trend curve of a process signal indicates a behaviour different from the predicted one while the operation of a plant is monitored by displaying a trend 00 graph of a plurality of process signals on a display device, it is necessary to operate the actuators of plant components related to the process signal indicating the anomalous Sbehaviour. Thus, it is required to easily and quickly select and display the actuator-display picture for Soperating the plant component related to this process Ve. ~signal.

However, in the above conventional techniques, since the plurality of trend curves, which are displayed on a display device, of the process variable related to a plant *o component are not correlated to the actuator-display picture o for manipulating the actuator of a plant component, it is impossible to easily and quickly select the actuator-display picture for manipulating the actuator of the plant component and operate the actuator with the actuator-display picture.

5.55 S 0°O° P:\operssb\3256240res.doc-02/07/01 -4- SUMMARY OF THE INVENTION An objective of the present invention is to provide a plant operating and monitoring system and a plant operating and monitoring method, by which an actuator-display picture related to a process signal displayed with a trend graph, are easily and quickly selected and displayed to operate the actuator of the plant component, or to at least provide a useful alternative.to the prior art.

The present invention provides a plant operating and monitoring system comprising: a computation unit for taking in state signals of a plant, which include process variables related to plant components, and performing plant-operation and monitoring; S 15 a display device for displaying a group of trend curves of a plurality of the process variables processed by said computation unit, on said display device; a plurality of operation means for controlling said process variables; 20 picture-displaying means for displaying a picture of a group of actuators including an actuator of one of said operation means, which is used for operating a process variable corresponding to a trend curve selected in said 25group of trend curves, when said trend curve has been 25 selected, on said display device along with said group of ****trend curves; S operation signal-input means for inputting an operation signal of each operation means whose actuator corresponding to said selected trend curve is displayed in said picture of said group of actuators on said display device to said computation unit; and process control means for controlling said operation P:\OPER\SSB32562OO docO2/7/0I -4Ameans based on said operation signal sent from said operation signal-input means.

The present invention further provides a method of operating and monitoring a plant by taking in state signals of said plant, which include process variables related to plant components in said plant, said method comprising the steps of: displaying trend curves of a group of process variables on a display device; displaying an actuator-display picture for manipulating an actuator to adjust a process variable corresponding to one of said displayed trend curves, on said display device along with said trend curves, if said trend curve is 15 optionally selected; and controlling said process variable by inputting an operation signal for manipulating said process variable for which actuator corresponding to said selected trend curve is displayed on said actuator-display picture.

A main feature of the preferred embodiment is to display both a trend graph and an actuator-display picture :corresponding to the trend graph on the same display device, eoe* 2 the actuator-display picture being retrieved by optionally 25 selecting one of the trend curves of a plurality of process signals which are displayed with the trend graph in order to manually operate the component related to the selected trend curve by using the actuator-display picture.

Further, in embodiments of the invention, it is possible to display a plurality of trend curves on a display device along with selection switches to select one of the trend curves, and to display the actuator-display picture related to the trend curve selected with the selection switches.

Furthermore, it is possible to equip the display device with a touch-screen in order to optionally select one of the P:\OPER\SSB\325624)O,-sdom.2/07/01 -4B displayed trend curves by using the touch-screen.

In a preferable embodiment, selection switches for selecting at least one of a plurality of trend curves are P:\OPER\SSBU2562-OOrc.doO2/07/0 I displayed on a display device along with the plurality of trend curves, and when at least one of the trend curves is selected, an actuator-display picture corresponding to the selected trend curve is displayed.

Further, it is possible that a touch-screen which is operated by a touch operation is provided on the display device, and one of the trend curves displayed on the display device is optionally selected by a touch operation on the touch-screen.

Meanwhile, a plurality of the actuator-display pictures can be displayed by being superimposed on a part of the picture displaying the trend curves or on the part of the operation-switches.

In accordance with a preferred embodiment of the 15 invention, an actuator-display picture related to an actuator (a plant component) for adjusting a process variable can easily and quickly be selected and displayed on .a display device by selecting one of the displayed trend curves of the process variables, and the actuator can be operated by using the actuator-display picture related with the actuator (the plant component) to be operated. This in turn makes it possible to easily and quickly take countermeasures to an anomaly occurring in the plant.

*ee 6 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic block diagram showing the composition of a plant operating and monitoring system of an embodiment according to the present invention.

Fig. 2 is a block diagram showing the detailed functional composition of the process computer in the system shown in Fig. 1.

Fig. 3 is a flow chart showing the operation of the plant operating and monitoring system of the embodiment.

10 Fig. 4 is another flow chart showing the operation of the plant operating and monitoring system of the embodiment.

Figs. 5A and 5B are examples of picture-displaying to show the operation of the system of the embodiment.

Fig. 6 is an example of the arrangement of operation-switches in a switch-operation unit.

Fig. 7 is an example of a process-input-data number o table.

Fig. 8 is an example of an actuator number table.

Fig. 9 is an example of a table of registered actuator-display picture numbers.

Figs. 10A and 10B other examples of picture-displaying to show the operation of the system of the embodiment.

Fig. 11 is an example of operating switches in the switch-operation unit.

Figs. 12A and 12B.other examples of picture-displaying 7 to show the operation of the system of the embodiment.

Figs. 13A and 13B other examples of picture-displaying to show the operation of the system of the embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS The composition of the plant operating and monitoring system of the embodiment according to the present invention is shown in Fig. 1.

The plant operating and monitoring system is used for 10 operating and monitoring each of the components composing a plant such as a thermal power generation plant, a nuclear power plant, water-works, sewage-works, a chemical processing plant, and so on.

In this figure, reference number 1 indicates a process computer which will be explained in detail later. A CRT display device 2 is controlled by a CRT control unit 3, and displays plant information such as a plant schematic diagram, a trend graph, etc., based on display information sent from 6 the process computer 1. The CRT display device 2 is equipped with a touch-screen 4.

The coordinates of the touch position on the touch-screen 4 are input to the process computer 1 via the touch-screen interface 5. Operation-switches 6 are used to input manual operation signals (ON/OFF signals or increase/decrease signals) for manually operating plant 8 components, and are composed of a plurality of operation-switches. The manual operation signals input from the operation-switches 6 are input to the process computer 1 via the operation-switch interface 7.

The keyboard 8 is used for inputting a signal (a picture-selection signal) to select a picture which is to be displayed on the CRT display device 2. The pictureselection signal input from the keyboard 8 is input to the process computer 1 via the keyboard interface 9. The plant 10 11 includes a plurality of actuators (plant components) 12 process signal transmitters (sensors) 13 to detect process variables.

Control signals for the actuators (plant components) 12, which are output from the process computer1, are input to the actuators (plant components) 12, and the process signals detected by the process signal transmitters ooo.

(sensors) 13 are input to the process computer 1 via the process input/output control unit The block diagram of detailed functions of the process computer 1 is shown in Fig. 2.

In Fig. 2, the picture-selection signal input by the operator with the keyboard 8 is input to an input keydetermination block 118. The input key-determination block 118 determines a picture (a trend graph) to be displayed on the CRT display device 2 based on the input picture-selection signal, and starts a trend graph-display picture-edition block 103.

The process signals detected by the process signal transmitters (sensors) 13 are input to a process signalinput block 101 via the process input/output control unit The process signal-input block 101 performs the conversion to engineering unit for the input process signal, and sends them to the trend graph-display picture-edition block 103. The trend graph-display picture-edition block 103 10 edits a trend-graph picture based on the process signals input to the process signal-input block, trend-graph picture .information in a table 102 of information on trend graph-display pictures, and trend graph-display items in a table 108 of registered trend-display items.

The data of the trend-graph picture edited by the trend ~graph-display picture-edition block 103 are output and displayed on the CRT display device 2 by a CRT picture-display block 104 via the CRT control unit 3.

The touch-screen 4 detects a touch on this screen when the operator touches the screen on the CRT control unit 3.

The detection signal detected by the touch-screen 4 is converted to the coordinates of the touch position by a touch position-input-control unit 5, and the converted coordinates of the touch position are input to a touch position-input block 105. A trend-displayed signal-determination block 106 determines the number of the selected trend-displayed signal based on the coordinates of the touch position, which are sent from the touch position-input block 105.

A process-input-data number-retrieval block 107 retrieves the process-input-data number of the designated process signal, which has been registered as a trenddisplayed signal, by referring to the table 108 of registered trend-display items. An actuator number-retrieval block 109 retrieves the actuator number corresponding to the 10 process-input-data number retrieved by the process- 9.

input-data number-retrieval block 107, by referring to an actuator number table 110.

An actuator-display picture number-retrieval block 111 retrieves the actuator-display picture number based on the actuator number retrieved by the actuator numberretrieval block 109, by referring to a table 112 of registered actuator-display picture numbers. An actuator-display picture-edition block 113 edits the actuator-display picture based on the actuator number retrieved by the actuatordisplay picture number-retrieval block 111, by referring to a table 114 of information on actuator-display pictures.

A CRT picture-display block 104 additionally displays the actuator-display picture edited by the actuator-display picture-edition block 113 on the CRT display device 2 via the CRT control unit 3 along with the trend-graph picture which has been displayed.

An operation-switch signal (a control mode signal and a manual operation signal) which has been input from the operation-switches 6 is input to an operation-switch signal-input block 115 via an operation-switch interface 7.

An operated-switch-determination block 116 determines the operation-switch signal input to the operation-switch signal-input block 115, and inputs a control mode signal and a manual operation signal to a process control signal- 10 generation block.

4* In the following, the operation of the system of this embodiment will be explained with reference to flow charts shown in Figs 3 and 4, and an example of a displayed picture shown in Fig. The operator inputs the number (the picture-selection signal) of a trend graph-display picture which the operator wants to monitor, by manipulating the operation-switches with the keyboard 8. The picture-selection signal is input to an input key-determination block 118. The input keydetermination block 118 determines the trend graph-display picture to be displayed, and starts the trend graph-display picture-edition block 103.

The trend graph-display picture-edition block 103 edits the trend graph-display picture to be displayed, based on the process signal input to the process signal-input block 12 101, the trend-graph picture information in the table 102 of information on trend graph-display pictures, and the trend graph-display items in the table 108 of registered trend-display items. The trend graph-display picture edited by the trend graph-display picture-edition block 103 is displayed on the CRT display device 2 by the CRT picture-display block 104 via the CRT control unit 3. In this way, the process computer 1 completes the process of step Sl shown in Fig. 3 by displaying the selected trend 10 graph-display picture on the CRT display device 2.

Here, if a new picture selection signal is input from the keyboard 8 while the trend graph-display picture is displayed on the CRT display device 2, data are newly added to the data stored in the table 102 of information on trend graph-display pictures. Consequently, trend curves corresponding to the added new data are also additionally displayed, or only trend curves corresponding to the newly *o added data used in place of the data which have been stored in the table 102 of information on trend graph-display pictures are displayed.

By the process of step Sl executed by the process computer 1, for example, the trend graph-display picture 21 shown in Fig. 5A is displayed on the CRT display device 2.

In the example shown in Fig. 5A, four trend curves No. 1 No. 4 are displayed. What trend curves are displayed is 13 determined according to the trend graph-display picture number which is input from the keyboard 8.

Further, six operation-switches 22 to which numbers 1 6 of the trend-displayed signals (the trend curves) are attached are displayed on the trend graph-display picture 21. Names of the process signals are displayed at the respective right hand sides of the operation-switches 22.

Also, it is possible to display the corresponding process-input-data numbers in place of the names of the 10 process signals. Moreover, if the six trend curves 1 6 in *s the trend graph are displayed with six different colors, it is possible to display the colors of the respective trend curves in place of the numbers of the respective trend curves.

It is assumed that while the plant is operated and monitored by displaying the trend graph-display picture 21 such as that shown in Fig. 5A, it has become necessary to manipulate one process variable corresponding to trend curve 2 displayed in the trend graph-display picture 21. Then, the operator touches the switch for the trend-curve number 2 in the displayed operation-switches 22. The touch on the operation-switches 22 performed by the operator is detected by the touch-screen.

The detection signal of the touch on the operation-switch, which has been detected by the touchscreen 4, is converted to the coordinates on the CRT screen 14 by the touch-screen interface 5. The process computer 1 determines that an operation-switch is selected in step S2 shown in Fig. 3, and proceeds to step S3. Conversely, if it is determined that no operation-switch is selected in step S2, the process goes to step S4.

In step S3, first, in step S31 of the flow chart shown in Fig. 4, the trend-displayed signal-determination block 106 determines the number of the trend-displayed signal selected by the touch based on the determined coordinates of the touched position. Next, in step S32, the block process-input-data number-retrieval block 107 retrieves the process-input-data number of the process signal o corresponding to the number of the selected trenddisplayed signal by referring to the table 108 of registered 15 trend-display items.

In the table 108 of registered trend-display items, which is shown in Fig. 2, the trend-displayed signal numbers 1 6 and the respective corresponding process-input-data numbers (for example, B215, B005, etc.,) are registered as shown in Fig. 7. In this example, the process-input-data number "B005" corresponding to the number of the selected trend-displayed signal is retrieved. The process-input-data number "BO05" retrieved by the process-input-data number-retrieval block 107 is sent to the actuator number-retrieval block 109.

P:\OPER\KAT32562-4 )prclinlln.doc-29 The actuator number-retrieval block 109 shown in Fig. 2 retrieves the actuator number based on the retrieved process-input-data number by referring to the actuator number table 110. In the actuator number table 110, the process-input-data numbers and the respective corresponding actuator numbers (for example, UM001, FW003, etc.,) are registered as shown in Fig. 8. The symbols UM, FW, FF, AF, ST, and RT shown in the actuator numbers in Fig. 8 indicate the manipulated variables of master unit-operation, feed water flow, fuel flow, air flow, steam temperature, and reheated steam temperature, respectively.

SThe actuator number-retrieval block 109 retrieves the actuator number "UM001" corresponding to the process-inputdata number "B005", and inputs the retrieved actuator number 15 "UM001" to the actuator-display picture number-retrieval block 111.

In step S34, the actuator-display picture numberretrieval block 111 shown in Fig. 2 retrieves the actuatordisplay picture number based on the actuator number by referring to the table 112 of registered actuator-display picture numbers. In the table 112 of registered actuatordisplay picture numbers, the actuator numbers and the actuator-display picture numbers (for example, "GUM001") are registered as shown in Fig. 9. The actuator-display picture numbers (for example, "GUM001") are created by adding to the actuator number (for example, "UM001") shown in Fig. 8.

For example, if the actuator number "UM001" is input to the actuator-display picture number-retrieval block 111, the actuator-display picture number-retrieval block 111 retrieves the actuator number "GUM001" in step S34.

The actuator-display picture-edition block 113 shown in Fig. 2 edits the actuator-display picture based on the retrieved actuator-display picture number by referring to 10 the table 114 of information on actuator-display pictures in step S35. In step S36, the CRT picture-display block 104 adds the edited actuator-display picture 24 to the trend graph-display picture 21 displayed on the CRT display device 2 based on the result of the actuator-display picture-edition executed by the actuator-display picture-edition block 113 via the CRT control unit 3, and display the integrated pictures.

Here, the actuator-display picture 24 can be composed such that it is erased from the integrated pictures displayed on the screen of the display device 2. For example, the actuator-display picture 24 is erased when the instruction to erase this picture 24 is input to the process computer 1 or when the operation or adjustment of the actuator corresponding to the selected trend curve is completed.

Also, it is possible that while an actuator-display 17 picture 24 is displayed on the display device 2, if an instruction signal to display a different actuator-display picture corresponding to another selected trend curve is input to the process computer 1, the later picture 24 is displayed in place of the former picture 24, or both the former and later pictures 24 are displayed as shown in Fig. 10 and Fig. 13.

In this way, the process in step S3 shown in Fig. 3, whose detailed processes are shown in Fig. 4, is executed by the process computer 1, and consequently the actuator-display picture 24 used for manipulating the process variable corresponding to the trend curve 2 is added to the trend graph-display picture 21, and the integrated pictures are displayed on the CRT display device 2 as shown in Fig. In the actuator-display picture 24, reference numbers 241 and 242 indicate a marker representation of a manipulated variable and a bar graph representation of an analog process variable, respectively. Further, reference numbers 243 and 244 indicate digital representations of a manipulated variable and a process variable, respectively.

00 00 o 0 On the other hand, if it is determined that no operation-switch is selected in step S2, the process in step S4 is executed by the touch position-input block 105. In step S S4, it is determined that the actuator-display picture 24 r- 18 has already been displayed on the CRT display device 2, and if it has been displayed, the process in step S5 is executed, otherwise the process returns to step S1.

When the processes in steps Sl S3 shown in Fig. 3 are executed by the process computer i, and the actuator-display picture 24 is displayed on the CRT display device 2, the process variable corresponding to the trend curve 2 is manipulated as follows.

The operator inputs a manipulation signal by operating the switch in the operation-switches 6. An example of the switch arrangement in the operation-switches 6 is shown in Fig. 6.

In the operation-switches 6 shown in Fig. 6, 8 switch groups (1 8) are provided corresponding to the maximum eeoc number of the actuator-display pictures which can be displayed on the CRT display screen at the same time, and switches and mean "open" (or "increase") and "close" (or "decrease"), respectively. Further, switches and "A" are the control mode-selection switches for switching the control mode, and means "automatic control" and "manual control", respectively. In the plant operation which is automatically controlled according to a control signal obtained based on signals detected by process variable sensors, the operation mode is set to be the automatic operation mode by selecting the switch If the automatic operation mode is switched to the manual operation mode in order to manually control the plant with a manipulation signal input by the operator, the operator operates the switch "A" or after the control mode is switched to the automatic control mode by selecting the switch Then, a manipulation signal for "open" (or "increase") or a manipulation signal for "close" (or "decrease") is input to the process computer 1 via the operation-switch interface 7.

Here, it is assumed that the switch group corresponding 10 to the above actuator-display picture 24 is the first switch group. When the switch of the control mode-selection switches in the first switch group is pushed, the control mode signal of the switch is input to the touch position-input block 105 in the process computer 1 via the operation-switch interface 7. The process computer 1 determines in step S5 shown in Fig. 3, that an operation-switch is pushed, and inputs the control mode signal to the operation-switch signal-input block 115 in step S6.

If the operated switch-determination block 116 determines in step S7 that the switch is pushed, the process control signal-generation block 117 switches the control mode to the manual control mode in step S8.

Further, if the switch or in the first switch group is pushed, and the manipulation signal is input, this manipulation signal as well as the control mode signal is input to the operation-switch signal-input block 115 via the operation-switch interface 7.

In step S7, the operated switch-determination block 116 determines the operational content of "open" (or "increase") or "close" (or "decrease") and the operation timing (the timing of starting the operation, the continuation interval of the operation) for the input manipulation signal. The process control signal-generation 10 block 117 generates a control signal based on the result of .i the determination executed by the operated switchdetermination block 116. The control signal generated by the process control signal-generation block 117 is output from the process computer i, and a corresponding. plant component is controlled with the control signal via the process input/output control unit While the plant is manually operated by operating the switches in the operation-switches 6, process signals registered in the table 114 of information on actuatordisplay pictures are input from the process signal transmitters 13 via the process input/output control unit and the actuator-display picture 24 displayed on the CRT display device 2 is continuously renewed. That is, the process variable 242 (displayed with a bar graph representation) and the manipulation signal 241 (displayed with a marker P:\OPER\KAn25(.2-4N)plinllund.ddoc.21)A5XM) -21representation) which are related to the plant component (actuator) 12, the digital display 243 of the manipulated amount, and the digital display 244 of the process variable are renewed.

As mentioned above, the operator can manually operate the plant component 12 while monitoring the trend curve 2 and the actuator-display picture 24.

In this way, it is possible to manually control a process variable corresponding to the trend curve which has indicated an anomalous behaviour. Thus, it is possible to easily and quickly select and display the picture of the actuator 12 to adjust the corresponding process variable by designating one of the displayed trend curves, which in turn makes it possible to easily take counter-measures to the anomaly occurring in the plant.

0 Here, although only one picture 24 of the actuatordisplay picture is displayed on the trend graph-display picture 21, it is apparent that process variables corresponding to two trend curves can simultaneously be controlled by displaying two actuator-display pictures 24A and 24B as shown in Fig. 10. In this case, for example, the 0 first and eighth switch groups in the operation-switches 6 are used as shown in Fig. 11.

Moreover, if some process variables of the plant are monitored for a long time, a trend graph-display picture 21 is often displayed on the whole screen of the CRT display device 2 as shown in Fig. 12A. In such a case, it is possible 22 to display an actuator-display picture 24 by superimposing it on the displayed trend graph-display picture 21. In this displaying method, since the right hand end of the trend graph indicates the present time, the actuator-display picture 24 is displayed by superimposing it on the left-hand end part of the displayed trend graph-display picture 21 as shown in Fig. 12B, or the picture 24 is displayed so as not to cover the specific point to be noticed in a trend curve.

Furthermore, an actuator-display picture 24 can be displayed on an optional location in the displayed trend graph-display picture 21, and the display location can be moved.

Fig. 13A shows an example of a trend graph-display picture 21 displayed on the whole screen of the CRT display .15 device 2, and Fig 13B shows an example of the superimposition display in which a plurality of actuator-display pictures 24A and 24B are simultaneously displayed on the screen of the CRT display device 2. In this example, the actuatordisplay picture 24A is displayed by superimposing it on the left-hand end part of the trend graph-display picture 21, and the actuator-display picture 24A is displayed by superimposing it on the displayed process signal names 23.

Also, although a trend curve is selected with the touch-screen 4, the selection of a trend curve, which is performed with a mouse-cursor by using a mouse, bring about P:\OPERKAT\32362-(XppliismzicAldm-2A)5AK -23the same effect as that in using the touch-screen 4.

Moreover, it is natural to provide a switch-operation means (a window of operation-switches) for the operation-switches 6 on the actuator-display picture 24 and operate the switchoperation means with a mouse-cursor.

As mentioned above, in accordance with the present invention, it is possible to easily and quickly select and display the picture of the actuator 12 to adjust the corresponding process variable by designating one of the displayed trend curves, which in turn makes it possible to easily take counter-measures to the anomaly occurring in the plant.

S.

S• Throughout this specification and the claims which follow, unless the context requires otherwise, the word 15 "comprise", and variations such as "comprises" and S* "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

20 The reference to any prior art in this specification is *ee@ not, and should not be taken as, an acknowledgment or any form of suggestion that that prior art forms part of the common general knowledge in Australia.

000 0 600 0 S

Z.)

Claims (14)

1. A plant operating and monitoring system comprising: a computation unit for taking in state signals of a plant, which include process variables related to plant components, and performing plant-operation and monitoring; a display device for displaying a group of trend curves of a plurality of the process variables processed by said computation unit, on said display device; a plurality of operation means for. controlling said process variables; picture-displaying means for displaying a picture of a group of actuators including an actuator of one of said operation means, which is used for operating a process 15 variable corresponding to a trend curve selected in said group of trend curves, when said trend curve has been selected, on said display device along with said group of trend curves; operation signal-input means for inputting an operation signal of each operation means whose actuator corresponding to said selected trend curve is displayed in said picture of said group of actuators on said display device to said computation unit; and eeoc process control means for controlling said operation 25 means based on said operation signal sent from said operation signal-input means. P:\OPER\SSB\32562 r.do-O2AO7/O

2. A plant operating and monitoring system according to claim i, wherein said display device displays said group of trend curves of said process variables on said display device along with selection switches for optionally selecting one in said group of trend curves.

3. A plant operating and monitoring system according to claim i, wherein said display device is equipped with a touch-screen which is operated by a touch operation, and one in said group of trend curves displayed on said display device is optionally selected by a touch operation on said touch-screen. A plant operating and monitoring system according to 5 claim i, wherein said display device displays said group of trend curves of said process variables on said display device along with selection switches for optionally S•selecting one in said group of trend curves, said display device being equipped with a touch-screen which is operated by a touch operation, and one in said group of trend curves :is optionally selected by a touch operation on said trend curve to be selected via said touch-screen.

5. A plant operating and monitoring system according to 25 claim i, wherein said picture-displaying means displays a *e 26 plurality of pictures which display respective actuators of said operation means.

6. A plant operating and monitoring system according to claim 1, wherein said picture-displaying means displays at least one picture which displays an actuator of said operation means, by superimposing said picture displaying said actuator on a part of a picture displaying said group of trend curves.

7. A plant operating and monitoring system according to claim 1, wherein said operation signal-input means inputs operation signal of actuators by using operation-switch operating means.

8. A plant operating and monitoring system according to claim 1, wherein said computation unit is a process computer for taking in state signals of a plant composed of a number of plant components, which include process variables related to said plant components, and performing plant-operation and monitoring.

9. A method of operating and monitoring a plant by taking in state signals of said plant, which include process variables related to plant components in said plant, said P:\OPERSSB\32562-OOr.doc02/071 -27- method comprising the steps of: displaying trend curves of a group of process variables on a display device; displaying an actuator-display picture for manipulating an actuator to adjust a process variable corresponding to one of said displayed trend curves, on said display device along with said trend curves, if said trend curve is optionally selected; and controlling said process variable by inputting an operation signal for manipulating said process variable for which actuator corresponding to said selected trend curve is displayed on said actuator-display picture.

10. A method according to claim 9, wherein a picture of selection switches for optionally selecting one of said S. displayed trend curves is displayed on said display device along with said trend curves, and one of said trend curves is optionally selected by using said selection switches. 20 11. A method according to claim 9, wherein said display device is equipped with a touch-screen which is operated by a touch operation, and one in said group of trend curves displayed on said display device is optionally selected by a touch operation on said touch-screen. oo00 P:OPER\SSBX32562-00s.doc-O2A)7/01 -28-

12. A method according to claim 9, wherein said display device displays said group of trend curves of said process variables on said display device along with selection switches for optionally selecting one in said group of trend curves, said display device being equipped with a touch screen which is operated by a touch operation, and one in said group of trend curves is optionally selected by a touch operation on said trend curve to be selected via said touch- screen.

13. A method according to claim 9, wherein if a plurality of trend curves in said group of trend curves displayed on said display device are optionally selected, actuator- display pictures for manipulating respective actuator which correspond to said selected trend curves are displayed on said display device. S"14. A method according to claim 9, wherein if one in said group of trend curves displayed on said display device is 20 optionally selected, an actuator-display picture used for manipulating a process variable corresponding to said selected trend curve is displayed, which is superimposed on a part of a picture displaying said group of trend curves. 29 A method according to claim 9, wherein said operation signal for said process variable is input via said actuator-display picture by using operation-switch operating means displayed on the same screen of said display device.

16. A method according to claim 9, wherein said plant is composed of a number of plant components, and said plant is operated and monitored by using said taken-in state signals 10 including said process variables related to said plant components. S. S P:\OPER\SSBU32562-0resdoc-02O7/01

17. A plant operating and monitoring system substantially as hereinbefore described with reference to the drawings.

18. A method of operating and monitoring a plant substantially as hereinbefore described with reference to the drawings. DATED this 2nd day of July, 2001 Hitachi, Ltd. AND Hitachi Information Control Systems Inc. by DAVIES COLLISON CAVE Patent Attorneys for the Applicant S* o So *S ee