JPS61281308A - Plant monitor device - Google Patents

Abstract

PURPOSE:To eliminate a wrong diagnosis of an abnormality, and to raise the reliability by providing a plant abnormal event holding circuit for holding an abnormality detecting input from a plant. CONSTITUTION:An abnormal temperature, etc. of a device 2 of a plant 1 are detected by detectors 3, 7, and they are outputted to a computer 8 through a converter 5. This computer 8 is provided with a plant diagnostic logic 9, a display device, a limit check 10, models 27, 31 which have simulated the device 2, etc., and monitors the plant 1. In this case, an abnormal event holding circuit 36 is provided. In this state, an output which has held a logical signal is outputted to an output from the limit check 10, transmitted exactly to the plant diagnostic logic 9, and the plant can be monitored without causing a wrong diagnosis. Also, when avoiding the subsequent abnormality, it is released by inputting a holding release input 37.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] Jin's invention relates to a plant monitoring device that monitors a conventional plant and outputs an appropriate message when an abnormality is detected.

[Conventional technology]

Conventionally, there has been a device as shown in FIG. 2 as a device for this purpose. In Figure 2, 1 is a plant, 2 is a plant 1
8 indicates a type of abnormality that occurs in equipment 2 (e.g. high temperature, low pressure, etc.). The detector outputs signal 4. A converter 6 converts the voltage level of the signal 4 and outputs the signal 6. 7
8 is a computer that detects a process quantity that has a causal relationship with the process quantity detected by the detector 8; ). 10 is a limit check of a software configuration that inputs the signal 6 of the converter 5 and outputs it at a level earlier than the normal alarm level of the plant 1, that is, at a level on the safe side of the plant 1. , a signal (binary signal) 11 is output. 12 is a start command (signal) for the plant diagnosis logic 9.

In the plant diagnosis logic 9, 13 is an observable point (hereinafter referred to as a node) that is detected as a warning in the plant diagnosis logic 9 when the signal 11 of the limit check 10 is turned on, and 14 is a node 18. Similarly, a node detected in the plant diagnosis logic 9 and connected to the detector 7 of the plant 1 (observable information)
, 15 is an AND gate, 16 is an OR gate, 17 is the minimum time delay (τ,) that occurs when going from a lower node 18 to an upper node 19, and 18 is a signal detected by node 18 as a warning. and the cause is node 1
A message 19, which is output after it is determined that the situation is at τ3. The node detected after the logical sum of τ4, 20 is the node in the final state where the abnormality extends, and 21 is the point. This is a virtual point where no vessel is installed.

Reference numeral 22 denotes a virtual logic, which is provided corresponding to the unobservable point 21 and simulates the route through which its influence spreads. 28 is a virtual node corresponding to point 21. 24 is point 21. Temporary sky logic 2
This message is additionally provided in the node 18 so as to correspond to the node 2 and the node 28, and instructs to avoid an abnormal state. 25 is one component within the device 2;
26 is a detector that detects the input signal to component 25; 27 is a model that simulates component 25, that is, exhibits characteristics equivalent to this; 29 is an adder that adds a predetermined margin value El and the output of model 27; A signal 80 is output having a component dynamic limit value that dynamically defines a component failure. 81 is a model simulating the device 2, and 82 is a model simulating the component 25. 84 is an adder that adds a margin value E2 for giving a margin to the model 81 and the output of the model 81, and outputs a system level dynamic limit value signal 86 that dynamically defines a failure at the device 2 level in the plant 1. do.

Next, the operation will be explained.

The signals output from the detectors 8 and 7 of the device 2 are converted by respective converters 5 and input to a limit check 10 of the computer 8. limit check 10
When the signal 11 is output, that is, when it turns on, the activation command 1 is activated.
2 (Thus, the plant diagnostic logic 9 is activated, and the signal 11 is detected at the node 18. It is known in advance that the abnormality in the detector 8 is an influence from the detector 7 or others, and the cause and effect relationship is unknown. The logic is simulated by the AND gate 15 and the OR gate 16. Therefore, at the time when the plant diagnostic logic 9 is activated, it is assumed that an abnormality has been detected before the alarm level is detected at the node 14. For example, the cause is that a situation occurs in which the node 14 is detected.Furthermore, the cause of the abnormality in the detector 8 is determined to be an abnormality in the detector 7, and this abnormality spreads. In order to prevent this, a message 18 is output to the operator.

Furthermore, when the plant diagnosis logic 9 is activated and the node 18 is detected, the logic above it is checked. As a result, the next possible state of the plant 1 can be predicted, and the operator can take precautions to avoid reaching the final state of node 201ζ. In addition, a minimum possible time τ3 is set in plant 1 between node 13 and node 19. Therefore, if node 19 is detected within a shorter time than time τ3 after node 18 is detected. If this occurs, node 1
It is determined that there is a failure in the detector 2 on the plant 1 side that detects 9.

In order to inform operators of these causes and future predictions, the diagnostic logic 9 of this plant 1 is displayed on a display device in the format shown in the diagram, and the displayed nodes 18 and 14 indicate abnormalities in the detectors 8 and 7, respectively. State variables and messages 18 are additionally displayed. This allows the operator to accurately grasp the state of the plant 1 and accurately perform operations to avoid abnormal conditions. However, after an abnormality was detected in No. 618, the nodes below node 18 were investigated to investigate the cause of the abnormality, but if no abnormality was detected in any node (cause identification failure), the abnormality It is determined that the cause is an abnormality at an unobservable point 21 within the plant 1, that is, the node 28 is abnormal.

Note that this message 24 has content stating that the cause of the abnormality is in an unobserved node, for example, node 28, and also includes instructions for operations in accordance with this.

In addition, if the detector 7 is a detector that detects the output signal of one component 25 constituting the device 2, that is, if it is assumed that the cause of the abnormality is a failure of the component 25, the The input signal of is detected by the detector 26. The output of the detector 26 is input via the converter 5 to a model 27 exhibiting characteristics similar to those of the component 25. The output of the model 27 is added to the margin value E by an adder 29, and the component 25 is dynamically defined in accordance with the movement of the component 25.
Obtain a signal value of 80 with a dynamic limit. As a result, the limit check 10 issues an accurate start-up command IJ even when the plant is in transition. Also, for example, in the node 18, a model 8 having the same characteristics as the device 2
By adding the margin value E2 to the input of 1, the device @
A signal 85 is determined which dynamically defines the fault of 2 in a manner consistent with its movement. As a result, all nodes including the nodes 18 and 14 in the plant diagnosis logic 9 can provide appropriate information to the operator even during plant transitions, making it possible to avoid abnormal noises in the plant.

[Problems that the invention attempts to solve]

Conventional plant monitoring equipment has the above-mentioned configuration, and once an abnormal event occurs, once the plant passes a certain mode, the abnormal event may disappear even though there is a cause for the abnormality. This has the disadvantage that all nodes are affected by this, resulting in a misdiagnosis of plant abnormality and an inaccurate abnormal situation avoidance message.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and by installing a circuit that holds the abnormality detection input from the plant, it instantly catches the abnormal timing by catching the transient event. The purpose of this system is to provide a plant monitoring device that can output highly reliable messages without erroneously diagnosing abnormalities. It is also intended to be able to produce.

[Means for solving problems]

The plant monitoring device according to the present invention is provided with a plant abnormal event holding device that holds abnormality detection input from the plant.

[Effect]

The plant monitoring device of this invention uses the plant's abnormal event holding device to instantly catch plant transient events and eliminates erroneous diagnosis of abnormalities.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, numerals 1 to 35 represent the same parts as in FIG. 8
6 represents an abnormal event holding circuit, and 37 represents h, a holding release signal input.

Next, the operations will be explained. Since operations 1 to 35 are the same as those of the conventional plant monitoring device, repeated explanations will be omitted below. An abnormal event holding circuit 86 capable of outputting an output holding a logical signal as an output from the limit check 10 is provided to accurately transmit even a transient abnormal event to the plant diagnosis logic and perform plant monitoring without causing erroneous diagnosis. After that, if the abnormality can be avoided, the operator or other person can perform the same operation as a normal ANN ryat to release the hold manually.87
I'll input it.

Although this invention was realized by S/W, it can also be realized by a hard-wired one.

〔Effect of the invention〕

As described above, according to the present invention, even abnormal events that occur transiently during the plant operation mode can be detected reliably, thereby eliminating the possibility of misdiagnosis and providing highly reliable information regarding plant abnormalities. This has the effect of being able to provide information to operators.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the plant monitoring device of the present invention, and FIG. 2 is a block diagram showing a conventional plant monitoring device. 1...Plant, 8,7.26...Detector, 5...
・Converter, 8... Computer, 9... Plant diagnosis logic, 10... Limit check, 1B, 1
4゜19.20,28...node, 16...and gate, 16...or gate, 21...point, 22...low altitude logic, 23...low altitude node,
25...Component, 27,11.82...Model, 29°84...Adder, 86...Abnormal event holding circuit, 87...Holding release signal input. Note that the same reference numerals in the figures indicate the same - or a corresponding portion.

Claims (1)

[Claims] When the output of a detector that detects the process amount input to a specific part of the plant indicates a second abnormality level that is set to be safer than a predetermined first abnormality level, the output of the detector is transmitted to the plant. In a plant monitoring device that performs the above diagnosis as an input condition for a logical decision tree for diagnosis, there is a model that has a response characteristic that simulates the above specific part and that introduces the output of the above detector, and a model that incorporates the output of this model. It is characterized by comprising an adder for adding a predetermined margin value, a limit check and an abnormal event holding device for detecting the second abnormal level based on the output of the adder and a status signal detected from the specific part. Plant monitoring equipment.