JPH0512051A - Fault diagnostic device for duplex system - Google Patents

Abstract

PURPOSE:To accurately estimate parts where an abnormality is generated at the time of abnormality detection by deciding whether or not a transmission system is normal every time the information transfer is performed between the control parts of the self station and the other station and storing the diagnostic result. CONSTITUTION:Respective reception signals of receivers 14a and 14b provided for each process control part 11 are entered in diagnostic circuits 17a and 17b. Each diagnostic circuit 17a and 17b executes the diagnostic processing such as the CRTC check for the received data and the detection of the non signal state of transmission systems 5a and 5b while comparing the mutual received data. Each diagnostic result is stored in a diagnostic storage part 18. When an abnormality is detected in the diagnostic result, the abnormality detection information is sent to the host control part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a duplication system in which a plurality of process control units are connected to a host control unit by a duplication transmission system, and particularly to a duplication system for automatically estimating an abnormal portion when a transmission error occurs. The present invention relates to a failure diagnosis device in a system.

[0002]

2. Description of the Related Art For example, in a computer system for controlling the process state of each equipment constituting a plant of a factory,
A process control unit incorporating a processor is assigned to each device of each facility, and each process control unit is connected to a host control unit including a host computer. In such a computer system, each process control unit is prevented from causing a trouble in a transmission system connecting each process control unit and between each process control unit and a higher-order control unit, which causes trouble in plant control. The transmission system connecting each other and each process control unit and the upper control unit is duplicated.

FIG. 5 is a block diagram showing a duplex system. One control unit 2 is assigned to each facility of the plant 1. Each control unit 2 incorporates a number of process control units 3 that control the operation of each device that constitutes the corresponding facility. And again each control unit 2
A pair of repeaters 4a and 4b are incorporated in each. An independent transmission system 5 is provided for each of the repeaters 4a and 4b.
a and 5b are connected. 1 for each transmission system 5a, 5b
The host upper control unit 6 is connected.

Each process control section 3 incorporated in each control unit 2 is connected to each transmission system 5a, 5 via a repeater 4a, 4b.
connected to b. The repeaters 4a and 4b are the plant 1
Is large, and the distance between each equipment is several km, for example.
In consideration of such cases, the signals transmitted through the transmission systems 5a and 5b are prevented from being attenuated. Therefore, a processor or the like having a judgment processing function is not incorporated in the repeaters 4a and 4b.

Each process control unit 3 takes in the process data of the equipment in charge of its own in the plant 1, executes a predetermined control calculation process, and outputs the calculation result to the corresponding device as a manipulated variable. Control movements.

In a normal state, the same information is transmitted by each of the transmission systems 5a and 5b. Therefore, when each process control unit 3 exchanges information with another process control unit 3 or the upper control unit 6, it receives information from either one of the transmission systems 5a and 5b and both transmission systems 5a. , 5b, the same information is transmitted simultaneously. Then, the host controller 6 receives the information of each process controller 3 from either one of the transmission systems 5a and 5b and displays it on the display 7a of the man-machine interface device 7, for example.

Generally, in such a duplex system, a diagnostic device for detecting a transmission abnormality is incorporated in each process control unit 3. That is, this diagnostic device simultaneously captures each information received via each transmission system 5a, 5b, performs a CRC check of the reception data of each transmission system, compares the reception data with each other, and transmits the received data to one transmission system. If there is no received data, it is determined that the relevant transmission system is abnormal, and control is performed so that the received data of the normal transmission system is input to the processor. Also, it informs the processor of abnormality detection information.
The processor of the process control unit 3 sends the abnormality detection to the upper control unit 6.

When the host controller 6 receives the abnormality detection via the normal transmission systems 5a and 5b, it displays it on the display 7a of the man-machine interface device 7. If the transmission systems 5a and 5b between the control units 2 or between the control units 2 and the upper control unit 6 fail, the other process control units 3 are also affected, so that the process control units 3 to It is highly possible that abnormality detection is sent to the control unit 6 at the same time. Therefore, the abnormality detection information of the plurality of process control units 3 is displayed on the same screen on the display 7 of the upper control unit 6. Since the probability that both transmission systems 5a and 5b fail at the same time is very small, this situation is ignored.

Each process control unit 3 has each transmission system 5a, 5b.
Since it is known in advance in what state the connection is made via, it is highly possible to specify in which section (position) of each transmission system 5a, 5b the abnormality has occurred.

For example, it is conceivable that an abnormality detection of all the process control units 3 constituting one control unit 2 is displayed as a result of transmitting information from the upper control unit 6 to each process control unit 3. The cause of failure is (1) all process control units 3 of this control unit 2 have failed,
(2) The repeaters 4a and 4b of the control unit 2 have failed, (3) One of the transmission systems 5a and 5b has failed,

Etc. are considered. However, it is very unlikely that all the process control units 3 shown in (1) will fail at the same time. If the transmission system 5a, 5b of (3) fails due to disconnection or the like, abnormality detection should be input from the process control units 3 constituting all control units 2 beyond this control unit 2. Therefore, this time, it can be estimated that (2) "the repeaters 4a and 4b of the relevant control unit 2 have failed".

In this way, when an abnormality relating to information transmission occurs in each process control unit 3, each process control unit 3 in which the abnormality occurs in the upper control unit 6 is displayed on the display 7a.
Is displayed, the monitoring personnel of the plant 1 can estimate the location of the abnormality from the abnormality detection state.

[0013]

As described above, since the abnormality detection information from the individual process control units 3 is collected by the upper control unit 6 and displayed on the display 7a, the location of the abnormality can be estimated. However, this estimation work depends on the judgment of the supervisor of the plant 1 as described above. Therefore,
An experienced observer who is familiar with the connection configuration of the entire redundant system that controls the plant 1 can make a proper judgment in a short time and estimate the correct abnormality occurrence point by comprehensively considering them. ..

However, an observer who is unfamiliar with the configuration of this duplex system or an inexperienced observer cannot make a correct decision in a short time. As a result, even if the wrong abnormal place is estimated, or even if the correct abnormal place can be estimated, it takes a lot of time from the time when the abnormal occurrence is confirmed until the correct conclusion is obtained. In this case, there is a problem that it is not possible to take prompt measures against the occurrence of an abnormality.

The present invention has been made in view of the above circumstances, and collects and analyzes the diagnostic results stored in each process control unit 3 when an abnormality is detected.
Even if an inexperienced observer who is not familiar with the system configuration is able to automatically estimate the location of an abnormality, he or she can confirm the proper location of the abnormality in a short time from the time when the abnormality was detected, and take quick measures against the occurrence of the abnormality. Therefore, it is an object of the present invention to provide a failure diagnosis device in a dual system that can improve the reliability of the entire system.

[0016]

In order to solve the above problems, according to the failure diagnosis apparatus in the duplex system of the present invention, information transmission between the process control unit and its own station and other control units is performed. Each time, the diagnostic means for diagnosing whether or not the transmission system between the own station and the partner control section is normal, the diagnostic result storage means for storing the diagnostic result by this diagnostic means, and the abnormality for the diagnostic means. An abnormality detection information transmitting means for transmitting abnormality detection information to the upper control unit when is detected,

Further, to the upper control unit, when the abnormality detection information is received from the process control unit, diagnostic result collecting means for collecting the respective diagnostic results from all the process control units and the respective diagnostic results collected from the respective process control units. An abnormality occurrence point estimation unit that estimates an abnormality occurrence point based on the above, and an abnormality occurrence point output unit that outputs an alarm to the abnormality occurrence point estimated by the abnormality occurrence point estimation unit.

[0018]

In the fault diagnosing device in the duplicated system configured as described above, each time the process control unit transmits information with another control unit, the transmission system between the local station and the partner control unit is changed. It is diagnosed whether it is normal or not, and the diagnosis result is stored. Then, when an abnormality is detected, the abnormality detection information is transmitted to the upper controller.

Upon receiving the abnormality detection information, the upper control unit collects the diagnostic results from all the process control units.
Then, the location of the abnormality is estimated from each diagnosis result. In this estimation procedure, the abnormality occurrence location is estimated according to the empirical algorithm as described above by comparing and comparing the normal and abnormal diagnostic results of each process control unit at the time of abnormality detection. The estimated abnormal place is displayed on, for example, a display. Therefore, the observer can grasp the exact location of the abnormality in a short time after the abnormality is detected.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a schematic structure of a dual system incorporating the failure diagnosis apparatus of the embodiment. Figure 5
The same reference numerals are given to the same portions as. Therefore, detailed description of the overlapping portions will be omitted.

In each control unit 2 assigned to each equipment of the plant 1, a large number of process control units 11 for controlling the operation of each equipment constituting the equipment and a pair of repeaters 4a and 4b are incorporated. ing. And each repeater 4
Independent transmission systems 5a and 5b are connected to a and 4b, respectively. One upper control unit 12 is connected to each of the transmission systems 5a and 5b.

Each process control section 11 is constructed as shown in FIG. 2, for example. Internal transmission systems 13a connected to the respective transmission systems 5a, 4b in the repeaters 4a, 4b,
Receivers 14a and 14b and drivers 15a and 15b are connected to 13b, respectively. Then, as for the reception signals of the receivers 14a and 14b, only one of the reception signals is selected by the switching circuit 19 and is input to the processor 16 which executes various information processing. Further, the transmission signal output from the processor 16 is transmitted to each driver 15
It is simultaneously output to the internal transmission systems 13a and 13b via a and 15b.

The received signals from the receivers 14a and 14b are input to the diagnostic circuits 17a and 17b, respectively. Each of the diagnostic circuits 14a and 14b performs a CRC check of the received data included in the received signal input to each diagnostic circuit, compares the received data with each other, and detects the non-signal state of one of the transmission systems 5a and 5b. Executes diagnostic processing for the transmission system. Each diagnostic result is stored in the diagnostic storage unit 18.

The diagnostic storage unit 18 stores the diagnostic result, and the diagnostic result is stored in one of the transmission systems 5a (13a),
When 5b (13b) is determined to be abnormal, the switching circuit 19 is switched to the side of the reception signal from the normal transmission system. Further, when the diagnosis storage unit 18 detects an abnormality in the diagnosis result, it sends an abnormality signal to the processor 16. Further, even when no abnormality is detected, the latest stored diagnostic result is transmitted to the processor 16 when the diagnostic result sending request is input from the processor 16.

In the duplex system having such a configuration, each process control section 11 of each control unit 2 has the same structure as that shown in FIG.
According to the flowchart of (a), the own station and other process control units 1
1 or a transmission process of various information between itself and the host controller 12.

When the flow chart is started and a transmission request is generated, the transmission process of information to the control units 11 and 12 of the other party is executed by the above-mentioned method (P1). Then, when the transmission process is completed, the diagnostic results in the diagnostic circuits 17a and 17b are written in the diagnostic storage unit 18 (P2). And
When an abnormality is detected in the diagnosis result (P3), the host controller 1
The abnormality detection information for No. 2 is transmitted (P4). It should be noted that if no abnormality is detected, it is not necessary to send it to the host controller 12. This completes the transmission processing of one information to the other control units 11 and 12. In this way, every time the transmission processing of one information is executed, the diagnosis is executed and the diagnosis recording unit 18
The storage content of is updated to the latest diagnosis result. The abnormality detected by each of the diagnostic circuits 17a and 17b mainly occurs in the following states. (1) Fault of own station Abnormality detection status: A transmission abnormality is detected in transmission with all control units. (2) Failure of partner control unit Abnormality detection status: An abnormality is detected only in transmission with the failure control unit, and the others are normal. (3) Repeater failure

Abnormality detected state: Transmission within the same control block is normally executed, but an abnormality occurs in transmission with an external control unit via a repeater.

The host controller 12 also executes the diagnostic process shown in FIG. 3 (b). That is, when the abnormality detection information is received from any one of the process control units 11 (P5), a request to send a diagnostic result is output to all the process control units 11 including the process control unit 11 that has detected the abnormality. Then, the diagnostic results stored in the diagnostic recording unit 18 of each process control unit 11 are collected (P6). When the diagnostic results of all the process control units 11 are collected, this diagnostic result and FIG.
Based on the connection configuration between the respective transmission systems 5a and 5b of the duplex system and the respective process control units 11 shown in FIG. 4, the abnormality occurrence place estimation processing is performed according to the algorithm shown in FIG. 4 (P7).

In FIG. 4, first, when no abnormality is detected in a plurality of process control units 11 (Q1),
It is determined that the process control unit 11 itself that has detected the abnormality is in failure. Further, at the same time, an abnormality is detected in a plurality of process control units 11, and in Q2, the process control unit 11 that has detected the abnormality is the process control unit 11 in one control unit 2.
If it is limited to the above, it is determined that the repeaters 4a and 4b incorporated in the control unit 2 have failed.

Further, for example, when an abnormality is detected in all process control units 11 beyond the specific control unit 2 (Q3), either one of the transmission systems 5a, 5b is detected.
It is determined that a failure such as a disconnection has occurred in a portion farther from the control unit 2 in question. Further, since it is considered that the probability of occurrence of anomaly detection states that do not satisfy the above algorithm is extremely small, the location of anomaly occurrence is not specified, but is classified into other anomaly occurrences collectively.

In this way, when the abnormality occurrence point is estimated by the algorithm shown in FIG. 4, the process returns to P8 in the flowchart of FIG. 3B, and the estimated abnormality occurrence point is displayed on the display of the man-machine interface device 7. It is displayed on 7 to warn the watchman.

In the case of the fault diagnosing device in the duplicated system configured as described above, the transmission systems 5a and 5b, the repeaters 4a and 4b of the control units 2 and the control units 2 in the duplicated system are installed. Each process control unit 1
If any abnormality occurs in 1, the diagnostic circuits 17a, 17 in any one or a plurality of process control units 11
b detects the abnormality. Then, at that time, the abnormality detection information is sent from the process control unit 11 to the upper control score 12. When the upper control unit 12 receives the abnormality detection information, it collects the diagnostic results at that time from all the process control units 11.

That is, since the upper control unit 12 can grasp the presence / absence information of the abnormality detection in each of the other process control units 11 at the time of the abnormality detection, it is based on the empirical rule and intuition that the skilled observer conventionally holds. The location of the abnormality is automatically estimated according to the created algorithm shown in FIG.

Therefore, when an abnormality is detected, the location of the abnormality is immediately displayed on the display unit 7a, so that even an observer who is not familiar with the connection configuration in this duplex system can reliably generate the correct abnormality. You can figure out where.

Further, it is necessary from the detection of an abnormality to the point of occurrence of an abnormality, as compared with the case where a conventional skilled observer estimates based on the state of each process control unit displayed on the display. The time is greatly reduced. as a result,
It is possible to take prompt measures against the occurrence of an abnormality.

The present invention is not limited to the above embodiment. In the apparatus of the embodiment, the algorithm shown in FIG. 4 is used as a method for identifying the location of the abnormality from each diagnostic result. However, the abnormal situation changes in various ways depending on the type of failure and the location where the failure occurs.
Therefore, the above-mentioned algorithm may not be able to deal with all the abnormalities. In some cases, it may be necessary to make a judgment according to the situation of each plant in which this redundant system is installed. For example, when a device that causes noise in a signal transmitted by the transmission system is installed near the transmission system, it is necessary to add abnormality detection due to the noise to the examination items.

It is difficult to add such a empirical rule peculiar to a plant to the above-mentioned general diagnostic items. Fuzzy reasoning is a method of using such uncertain elements to estimate the location of anomalies. Therefore, it is also possible to specify the location of the abnormality with such a fuzzy inference method.

[0039]

As described above, according to the failure diagnosing device of the present invention, the presence or absence of an abnormality is diagnosed with respect to each process control section every time information is transmitted, and the diagnosis result is stored.
When the upper control unit receives the abnormality detection from the process control unit, it collects each diagnostic result and estimates the location of the abnormality. Therefore, even if an inexperienced observer who is not familiar with the connection configuration of the redundant system to be monitored, the abnormal place can be surely and promptly grasped. Therefore, it is possible to take prompt measures against the occurrence of an abnormality, and it is possible to significantly improve the reliability of the entire duplex system.

[Brief description of drawings]

FIG. 1 is a block diagram showing an entire duplex system incorporating a failure diagnosis device according to an embodiment of the present invention,

FIG. 2 is a block diagram showing a schematic configuration of each process control unit in the system of the embodiment.

FIG. 3 is a flow chart showing the operation of the apparatus of the embodiment,

FIG. 4 is a flow chart showing an algorithm for estimating a location where an abnormality has occurred in the apparatus of the embodiment;

FIG. 5 is a block diagram showing an entire general duplex system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Plant, 2 ... Control unit, 4a, 4b ... Repeater, 5a, 5b ... Transmission system, 7a ... Indicator, 11 ... Process control part, 12 ... Upper control part, 14a, 14b ... Receiver, 15a, 15b ... Driver, 16 ... Processor, 1
7a, 17b ... Diagnostic circuit, 18 ... Diagnostic recording section, 19 ... Switching circuit.

Claims (1)

Claim: What is claimed is: 1. A plurality of process control units are connected to a host control unit by a redundant transmission system, and when an abnormality occurs in one of the transmission systems, each process is performed in the other transmission system. In a duplex system that performs information transmission between control units and between each process control unit and a higher-order control unit, each process control unit performs information transmission between its own station and another control unit, Diagnostic means for diagnosing whether or not the transmission system between the own station and the partner control section is normal, diagnostic result storage means for storing the diagnostic result by this diagnostic means, and when abnormality is detected by the diagnostic means An abnormality detection information transmitting unit for transmitting abnormality detection information to the upper control unit, and the upper control unit, when receiving the abnormality detection information from the process control unit, collects each diagnostic result from all the process control units. With diagnostic result collection means An abnormality occurrence point estimating means for estimating an abnormality occurrence point based on each diagnostic result collected from each process control section, and an abnormality occurrence point outputting means for outputting an alarm to the abnormality occurrence point estimated by the abnormality occurrence point estimating means A fault diagnosis device in a duplex system, characterized by having.