JPH0468647B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a plant abnormality diagnosis device for diagnosing abnormalities in a plant.

[Technical background of the invention and its problems] As a method for diagnosing abnormality in a plant using process signals obtained from the plant, the causal relationship of abnormality propagation is expressed in a tree-like manner using logical symbols.
There is a method of knowing the cause of plant abnormality, the current state, and predicted future changes in the plant state from changes in process signals on the logical tree. In this type of plant diagnosis method, the abnormality propagation is expressed in a tree-like manner, so if a previously assumed abnormality occurs, the cause of the abnormality can be found early and the cause can be detected along the logical tree. Propagation can be predicted. However, when an unexpected abnormality occurs, that is, an abnormality that is not represented on the logical tree, there is a problem in that the abnormality cannot be diagnosed along the logical tree. Additionally, since the propagation of anomalies is expressed in a unidirectional manner on the logical tree, there is a problem in that if the plant state moves toward recovery due to manual or automatic operation, it will not be possible to deal with subsequent changes in the plant state. . Moreover, in the conventional diagnostic method, only one type of steady state is considered, so the steady state after a change in the plant output is regarded as an abnormality, and it is assumed that correct diagnosis may not be possible. Therefore, there has been a demand for the development of a plant abnormality diagnosis device that can perform abnormality diagnosis even after a plant recovery operation is initiated or when a plant output is changed.

[Object of the invention] The present invention has been made in view of the above circumstances, and
The purpose is to develop a plant abnormality diagnosis system that can detect plant abnormalities early and move the plant toward recovery, not only when the cause of the abnormality has been determined, but also when the cause of the abnormality is not determined. It is on offer.

[Summary of the Invention] In order to achieve the above object, the present invention includes a signal transmission device that inputs a process signal collected from a plant, and a signal transmission device that inputs the process signal from the signal transmission device at regular intervals to transmit the process signal. A plant condition monitoring section that determines an abnormal state of the plant based on a combination of process values that are out of the allowable range among the signals; an abnormality cause diagnosis section that diagnoses the cause of the plant abnormality based on the combination of the states of the process signals; and the plant state monitoring section. and a recovery operation exploration unit that inputs respective output signals from the abnormality cause diagnosis unit and instructs a recovery operation procedure for the abnormal state of the plant, the plant status monitoring unit, the abnormality cause diagnosis unit, and the recovery operation exploration unit. The present invention relates to a plant abnormality diagnosis device comprising a diagnosis result display section that displays diagnosis results obtained by the present invention.

[Embodiments of the invention] Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of the present invention, in which process signals obtained from a plant 1 at regular intervals are inputted to a plant condition monitoring section 4 and an abnormality cause diagnosis section 5 via a signal transmission device 2.

In the plant condition monitoring unit 4, a threshold value is set in advance for the main process values of the plant according to the output of the plant, and it is determined whether or not there is a process value within this threshold value. If there are process values, it is determined based on the combination of process values that are outside the allowable range what kind of abnormal state the plant is in and what should be done, and the results are input to the recovery operation exploration section 7.

For example, FIG. 2 shows an example of the diagnosis results of the plant condition monitoring section when an abnormality diagnosis of a boiling water nuclear power plant is carried out. In this figure, the ○ mark in the upper row 15 indicates that the reactor pressure 11, main steam flow rate 12, and core flow rate 14 are within the allowable range, and the - mark in the upper row 15 indicates that the reactor water level 10 and the feed water flow rate 13 are below the allowable value. shows. The ↓ mark in the lower row 16 indicates the direction of the rate of change of the process signal, indicating that the reactor water level 10 and the feed water flow rate 13 are decreasing.
Then, when the process signal is below the allowable value and the direction of change is rising, it is determined that recovery is on the way. In the example shown in Figure 2, in order to restore the reactor water level, it is necessary to increase the feed water flow rate or reduce the core flow rate to reduce the main steam flow rate.
This information is input to the recovery operation exploration section 7.

In addition, the abnormality cause diagnosis unit 5 detects the cause of abnormality in the plant at an early stage based on the combination of process signal states, and when the cause of the abnormality is detected, presents a recovery operation to prevent the spread of the abnormality. The fact that a certain device cannot be used is input to the recovery operation exploration section 7. In this case, the state of the process signal depends on whether the signal exceeds a threshold predetermined for each analog signal if the signal is an analog signal, or depending on the on/off state if the signal is a digital signal. Examine the state of process signals.

For example, an example of the database 6 of the abnormality cause diagnosis section 5 is shown in FIG. 17 is a signal when the output of the main water supply controller has decreased, 18 is a signal when the main water supply controller is under automatic control, and 19 is a signal when the input of the main water supply controller has not decreased. The low side fault 20 of the controller is caused by the AND gate 21.
It is established when the above-mentioned signals 17, 18, and 19 are all established, and at this time, an operation guide for manually controlling the controller of each water supply pump is presented, and the recovery operation exploration unit 7 indicates that the main water supply controller cannot be used. Enter.

Furthermore, the recovery operation exploration unit 7 searches for an operation to correct the plant condition in response to a request from the plant condition monitoring unit 4, and determines whether the equipment operates normally based on the state of input/output signals of the equipment related to the recovery operation. Investigate,
If use of the device is not authorized, seek alternative operations. Furthermore, if it is clear from the signal from the abnormality cause diagnosis section 5 that the device is malfunctioning, the use of that device is excluded from the beginning.

For example, when a request to increase the feed water flow rate or decrease the core flow rate is input from the plant status monitoring unit 4, it is determined whether the feed water pump is operating normally based on the input/output signal status of the feed water pump and the status of related valves. If it is normal, check the status of the water pump controller. Based on the results, it is determined whether or not it can be used, and if all operations to increase the feed water flow rate are impossible, an operation to reduce the core flow rate is found and the results are presented. Note that a priority is set for each operation to increase the water supply flow rate, and whether or not the operation is possible is determined in order of priority.

Next, a flowchart according to this embodiment will be explained with reference to FIG.

First, when an abnormality occurs in the plant in the first step 101, the cause of the abnormality is determined in the next second step 102, and if the cause of the abnormality is found, the recovery operation i is determined (determined) in the third step 103. i=1 to n). Fourth step 104
Then, it is determined whether or not it can be used in the recovery operation i, and if it is usable, the diagnosis result is displayed in the next fifth step 105. If it is not usable in the fourth step 104, then in the sixth step 106, on the condition that i<n holds, it is updated to i+1 and inputted in the third step 103, and from then on, the above procedure is repeated until the recovery operation becomes usable. The procedure is repeated. If the second
If the cause of the abnormality is not determined in step 102 or if i<n does not hold in the sixth step 106, the plant state is determined in the seventh step 107, and then the recovery operation j is performed in the next eighth step 108. A determination is made, and in a ninth step 109 it is determined whether or not it can be used in the recovery operation j, and if it can be used, the diagnosis result is displayed in the next fifth step 105.
If the recovery operation j is not usable at the ninth step 109, it is updated to j+1 and inputted to the eighth step 108, and the process is repeated until the recovery operation becomes usable.

[Effects of the Invention] According to the plant abnormality diagnosis device of the present invention, the cause of the abnormality can be found early in the abnormality cause diagnosis section, and the plant state can be directed towards recovery. In addition, the plant status monitoring unit monitors the balance status of the plant even when the cause of an abnormality is not determined, when the plant output is changed, or when a recovery operation is being performed, so it is possible to detect the abnormality and recover the plant status. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention.
FIG. 2 is a diagram showing an example of the diagnosis result of the plant condition monitoring section shown in FIG. 1, FIG. 3 is a diagram showing an example of the database of the abnormality cause diagnosis section shown in FIG. 1, and FIG. This is a flowchart for an example. 1...Plant, 2...Signal transmission device, 3,
6, 8...database, 4...plant condition monitoring section, 5...abnormality cause diagnosis section, 7...recovery operation exploration section, 9...diagnosis result display section.

Claims (1)

[Claims] 1. A signal transmission device that inputs process signals collected from the plant; and a signal transmission device that inputs the process signals from the signal transmission device at regular intervals to detect abnormal conditions in the plant due to a combination of process values outside the allowable range of the process signals. a plant condition monitoring section that determines the condition of the plant; and an abnormality cause diagnosis section that diagnoses the cause of the abnormality in the plant based on a combination of the states of the process signals; a recovery operation exploration unit that instructs a recovery operation procedure for an abnormal state of Features: Plant abnormality diagnosis equipment.