JP2004334418A - Abnormality detecting device and method for automation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the abnormality of an automation system with a small amount of data. <P>SOLUTION: The diagnostic system 10 is configured of an object system 12 having a plurality of pieces of field equipment 25 and an abnormality detecting device 13 for detecting the abnormality of the object system 12 to specify the factor of the abnormality. The abnormality detecting device 13 is provided with a monitoring function 41 which monitors the operating condition of the object system 12 and a diagnostic function 42 which diagnoses the object system 12 based on the monitor result of the monitoring function 41.The monitoring function 41 is provided with an arithmetic means 45 which calculates the valid availability of energy from predetermined state quantity in the object system 12 and a comparing/deciding means 46 which judged that there is possibility that any abnormality is generated when the calculated valid availability of the energy is made lower than a normal value. The diagnostic function 42 is provided with a factor specifying means 51 which specifies the factor of the abnormality from the status quantity when it is judged that there is possibility that the abnormality is generated. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an abnormality detection apparatus and an abnormality detection method for an automation system, and more particularly, to an abnormality detection apparatus and an abnormality detection method for an automation system that can detect an abnormality in the automation system with a small amount of data.
[0002]
[Prior art]
Many diagnostic systems that determine the presence or absence of the abnormality in process automation and the like are known (for example, see Patent Document 1). Such a diagnostic system collects various state quantities, such as temperature, pressure, and flow rate, detected by many field devices in a short cycle using a computer, and constantly compares the respective state quantities with their normal values. Thus, the abnormality is determined from a comprehensive point of view.
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-250519
[Problems to be solved by the invention]
However, in the diagnostic system, irrespective of the presence or absence of the abnormality, enormous types of state quantities are collected in a short cycle, and the state quantities are always compared with normal values. In addition to the heavy load imposed on the computer that performs the above processing, there is also the disadvantage that the communication load between the computer and the field device also increases. Particularly, in recent plants and the like, in order to realize high-efficiency operation, advanced and complicated control technology has been introduced, so that the above-mentioned disadvantages become more remarkable.
In addition, from the viewpoint of effective use of energy and protection of the global environment, the future power and energy systems will be changed from large-scale centralized systems to small- and medium-sized and self-contained distributed systems such as household units. It is important to construct a system that can effectively use not only the electric energy generated by the private power but also the heat energy generated at the same time. In order to spread such systems, it is necessary to be able to autonomously diagnose abnormalities in each system. In this case, however, data processing must be performed from the viewpoint of promoting simplification of the system configuration. It is desirable to be able to detect system abnormalities without imposing a load on communication and communication.
[0005]
[Object of the invention]
The present invention has been devised in view of such inconveniences and the like, and has as its object to provide an abnormality detection device and an abnormality detection method for an automation system that can detect an abnormality in the automation system with a small amount of data. Is to do.
[0006]
[Means for Solving the Problems]
To achieve the above object, the present invention provides an apparatus for detecting an abnormality in a predetermined automation system,
The abnormality is detectably provided based on the effective use of energy in the automation system. According to such a configuration, since the effective utilization of energy can be obtained by using a part of state quantities of various devices and the like existing in the automation system, the abnormality of the automation system is detected. In doing so, it is not necessary to constantly compare all state quantities with normal values, and it is possible to detect an abnormality in the automation system with a small amount of data. Moreover, the effective energy utilization obtained here can be used as an index that indicates the degree of energy saving of the automation system. Changes can be made easily.
[0007]
In the present invention, a monitoring function for monitoring an operation state of the automation system, and a diagnostic function for diagnosing the automation system based on a monitoring result by the monitoring function,
The monitoring function is a computing unit that computes the effective utilization of the energy from a predetermined state quantity in the automation system, and compares the computed effective utilization of the energy with a normal value, so that the effective utilization of the energy is A comparison determining unit that determines that the abnormality may have occurred when the value is lower than the normal value,
The diagnostic function includes a cause for determining the cause of the abnormality from the state quantity or the state quantity necessary for specifying the cause when the comparison determining means determines that the abnormality may have occurred. It is preferable to adopt a configuration including a specifying means. With this configuration, when there is a possibility of an abnormality in the automation system, it is possible to sequentially collect the corresponding state quantities and specify the cause of the abnormality. It is no longer necessary to constantly collect, communicate, and the like data regardless of the presence or absence of an abnormality, and it is possible to identify the cause of the abnormality by reducing the data processing and communication loads.
[0008]
Further, the monitoring function employs a configuration including a collecting unit that measures and collects a predetermined state quantity in the automation system.
[0009]
Further, a configuration is adopted in which a monitoring state notifying unit that notifies the cause specifying unit of the execution of the diagnosis when the comparison determining unit determines that the abnormality may have occurred is adopted. can do.
[0010]
Further, it is possible to adopt a configuration in which a diagnosis result notifying unit for notifying a predetermined device of a diagnosis result by the cause specifying unit is further provided.
[0011]
Further, it is preferable to adopt a configuration in which the monitoring function and / or the diagnostic function are implemented in a function block of a field device. According to such a configuration, monitoring and diagnosis of the system can be performed at the field level, which can contribute to space saving of the system, greatly reduce the burden on data communication, and increase the amount of information. It is possible to construct a diagnostic algorithm based on the algorithm. In addition, the data communication means and the function blocks are mounted in a form compatible with an open network such as Foundation Fieldbus, PROFIBUS, HART, etc., thereby facilitating system construction and reducing system construction costs.
[0012]
Further, it is preferable that a part or all of the state quantity is collected by a multivariable type field device capable of detecting a plurality of state quantities by one device. According to such a configuration, the number of field devices in the system can be reduced, which can further contribute to space saving of the entire system.
[0013]
Further, the present invention provides a method for detecting an abnormality of a predetermined automation system using a computer,
Calculate the effective utilization of energy in the automation system, and when the effective utilization of the energy falls below a predetermined normal value, determine that there is a possibility that an abnormality has occurred in the automation system. In addition, a state quantity corresponding to the cause of the abnormality is sequentially investigated to identify the cause of the abnormality, and a method is adopted. The above-described object can also be achieved by such a method.
[0014]
In this specification, the term "automation system" refers to any system that automatically controls equipment in a predetermined state, and is a concept that integrates power / energy systems such as plants, process automation, mechanical automation, home automation, and the like. Used as
[0015]
The term “effective energy utilization” refers to an index indicating the efficiency (corresponding to the input / output ratio of energy) in various energy conversion processes. For example, the system efficiency of a power / energy system can be exemplified. Examples of the effective utilization of the equipment include boiler efficiency of a boiler, turbine adiabatic efficiency of a steam turbine or the like, heat transfer rate of a heat exchanger or the like, pump efficiency of a pump, and the like.
[0016]
Further, the term "field device" is used as a general term for industrial instruments for measuring a flow rate, a temperature, a pressure, a liquid level, and the like, and examples thereof include various sensors and actuator devices such as valves.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0018]
FIG. 1 is a schematic configuration diagram of a diagnostic system including the abnormality detection device according to the present embodiment. In the figure, a diagnostic system 10 includes a predetermined automation system 12 to be diagnosed (hereinafter, referred to as a “target system 12”) and an abnormality detecting device that detects an abnormality of the target system 12 and identifies a cause of the abnormality. 13 and an upper-level management device 14 that is provided so as to enable data communication between the abnormality detection device 13 and the computer that manages the target system 12.
[0019]
Although the target system 12 is not particularly limited, in the present embodiment, process automation related to a heat exchange process between steam and water is employed. As shown in FIG. 2, the target system 12 includes a boiler 17 for generating steam, a steam line 18 connected to the boiler 17, and a shell-and-tube type heat exchanger 19 to which steam is supplied from the steam line 18. And water lines 22 and 23 on the inlet side and the outlet side which are connected between the heat exchanger 19 and a predetermined water storage unit 21, and a plurality of field devices 25 appropriately provided in the respective lines 18, 22 and 23. , And a condensed liquid discharging means 27 for discharging the condensed liquid from the heat exchanger 19.
[0020]
In the target system 12, the water in the water storage unit 21 is supplied from a water line 22 on the inlet side to a heat transfer tube (not shown) in the heat exchanger 19 using a pump or the like (not shown). Steam from the boiler 17 is supplied to a shell (not shown) located around the heat pipe, and heat exchange is performed between water in the heat transfer pipe and steam in the shell. The water after the heat exchange is returned to the water storage section 21 through the water line 23 on the outlet side, and heat is consumed in the process.
[0021]
The field device 25 includes a steam flow meter 29 that detects a flow rate of steam in the steam line 18, and a pressure for a heat exchanger that detects a pressure in the shell (not shown) that becomes a steam flow path in the heat exchanger 19. A water flow meter 31 for detecting a flow rate in the water line 22 on the inlet side, an inlet water temperature meter 32 for detecting a water temperature in the water line 22 on the inlet side, and a water line 23 for the outlet side. The apparatus includes an outlet-side water meter 33 for detecting the water temperature of the air-fuel ratio, and a valve device 25 provided in each of the lines 18, 22, 23 and the like. Although not shown, the target system 12 includes many other field devices.
[0022]
The condensed liquid discharging means 27 temporarily stores the condensed liquid in the heat exchanger 19 in a tank 36, and when a water level in the tank 36 becomes higher than a predetermined level, a pipe 38 extending from the tank 36 to the outside. The valve device 34 arranged on the way is operated to open the conduit 38 and drain the condensate in the tank 36 to the outside.
[0023]
The abnormality detection device 13 is configured by a predetermined computer, and as shown in FIG. 1, a monitoring function 41 for monitoring an operating state (operating state) of the target system 12 and a monitoring result by the monitoring function 41. And a diagnostic function 42 for diagnosing the target system 12 based on the information.
[0024]
The monitoring function 41 includes a collection unit 44 that measures and collects various state quantities (flow rate, pressure, temperature, etc.) in the target system 12 at a predetermined timing, and a collection unit 44 that measures energy in the target system 12 based on the collected predetermined state quantities. Calculating means 45 for calculating the effective utilization; comparison determining means 46 for comparing the calculated effective utilization of energy with a predetermined normal value (reference value) to determine whether there is a possibility of abnormality; When it is determined that the effective utilization of energy is lower than the normal value, the management device notifies the diagnostic function 42 of the execution of the diagnosis, and also determines the computed effective utilization of energy and the presence or absence of an abnormality based on the computed utilization. And a first notifying unit 47 (notifying unit of a monitoring state) for notifying the monitoring unit 14.
[0025]
The calculating means 45 calculates a heat transfer rate representing the heat transfer performance of the heat exchanger 19 from the four types of state quantities detected from the field device 25. Specifically, this heat transfer rate is obtained by the state quantities (pressure, flow rate, temperature) obtained by the heat exchanger pressure gauge 30, the inlet water flow meter 31, the inlet water thermometer 32, and the outlet water thermometer 33, respectively. Is substituted into a predetermined thermodynamic arithmetic expression stored in advance. The heat transfer rate also serves as a monitoring item for the user and the like, and is distributed to the management device 14 through the first notification unit 47 as described above.
[0026]
When the calculated effective utilization of the energy is lower than the normal value, the comparison determining means 46 determines that there is a possibility that an abnormality has occurred in the target system 12. The normal value here is stored in the comparison determining means 46, and is a predetermined theoretical value, a set value, or a value that is constantly updated based on chronological operation data.
[0027]
The diagnosis function 42 includes a cause identification unit 51 that identifies the cause of the abnormality from the state quantity collected by the collection unit 44 based on a command from the first notification unit 47, and a result of the cause identification unit 51 Is provided with a second notifying unit 52 (notifying unit of a diagnosis result) for notifying the managing device 14 or the like by an alarm, an e-mail, or the like.
[0028]
The cause identification unit 51 sequentially investigates the state quantities of one or a plurality of diagnostic items while sequentially collecting the corresponding state quantities via the collection unit 44 based on a diagnostic algorithm stored in advance, and determines whether an abnormality has occurred. The cause is identified step by step. In the present embodiment, the event tree of FIG. 3 including a plurality of diagnosis items is used, and for each diagnosis item, it is sequentially checked whether or not the value of the corresponding state quantity is within a predetermined value range. According to the result, the presence or absence and the cause of the abnormality of the target system 12 are specified.
[0029]
Next, an abnormality detection procedure by the diagnostic system 10 will be described mainly with reference to FIG.
[0030]
First, during operation of the target system, when the comparison and determination means 46 (see FIG. 1) determines that the current heat transfer rate is lower than a predetermined normal value (step S101), the heat exchanger 19 (see FIG. 1). 2) is determined (step S102). This determination is made based on the detection value of the inlet water flow meter 31 (see FIG. 2). As a result, when the flow rate is decreasing, it is a change in the heat transfer rate due to the change in the operating point of the operation, and a diagnosis is made that the target system 12 has no abnormality.
[0031]
On the other hand, if not, it is next determined whether or not the pressure of the steam in the heat exchanger 19 is higher than a predetermined value (step S103). This determination is made based on the detection value of the heat exchanger pressure gauge 30 (see FIG. 2). As a result, when the pressure of the steam in the heat exchanger 19 is increasing, a diagnosis is made that air is retained in the shell, which is the steam flow path of the heat exchanger 19.
[0032]
On the other hand, if not, it is next determined whether or not the water temperature difference before and after the heat exchanger 19 is smaller than a predetermined value (step S104). This determination is made based on the difference between the detected values of the inlet and outlet water thermometers 32 and 33 (see FIG. 2). As a result, if the water temperature difference has decreased, it is determined whether the flow rate of the steam in the steam line 18 (see FIG. 2) has decreased below a predetermined value (step S105). This determination is made based on the detection value of the steam flow meter 29 (see FIG. 2). As a result, when the flow rate of the steam in the steam line 18 is decreasing, it is a change in the heat transfer rate due to the change of the operating point of the operation, and a diagnosis is made that there is no abnormality in the target system 12. . On the other hand, when the flow rate of the steam in the steam line 18 has not decreased, the malfunction of the valve device 34 provided in the condensed liquid discharge means 27 (see FIG. 2) or the flow of the water in the heat exchanger 19 A diagnosis is made to the effect that an abnormality such as clogging of the heat transfer tube serving as a path has occurred.
[0033]
If it is determined in step S104 that the water temperature difference before and after the heat exchanger 19 has not decreased, the average value of the respective water temperatures in the inlet and outlet water lines 22, 23 (see FIG. 2) (see FIG. 2). Hereinafter, it is determined whether or not “water temperature” is lower than a predetermined value (step S106). In this case, the determination is performed based on the average value of the detection values of the inlet and outlet water thermometers 32 and 33. As a result, if the average temperature of the water has decreased, it is determined whether or not the water temperature in the inlet-side water line 22 has decreased from a predetermined value based on the detection value of the inlet-side water temperature gauge 32. Is performed (step S107). As a result, when the water temperature in the water line 22 on the inlet side is decreasing, the change is the change in the heat transfer rate based on the decrease in the water temperature in the water line 22 on the inlet side. No diagnosis is made. On the other hand, when the water temperature in the water line 22 on the inlet side has not decreased, a diagnosis that there is another abnormality is made.
[0034]
If it is determined in step S106 that the average temperature of the water has not decreased, it is diagnosed that there is an abnormality in the device or the like for measuring the state quantity.
[0035]
Therefore, according to such an embodiment, the monitoring function 41 makes a primary determination as to whether or not there is a possibility that the target system 12 may be abnormal, based on the heat transfer rate, which is an index indicating the effective utilization of energy. Only when there is a possibility that an abnormality has occurred, the diagnostic function 42 checks the necessary state quantities sequentially, and makes a secondary determination on the identification of the abnormal part. For this reason, the primary judgment can be performed without using data of all state quantities, and the occurrence of an abnormality can be detected in a state where the load on data processing and communication is reduced, and the cause can be efficiently determined. The effect of being able to specify is obtained. In addition, since the heat transfer rate is also distributed to the management device 14 side, the state of the heat transfer rate can be confirmed on the management device 14 side, which can be used for a highly efficient operation of the target system 12.
[0036]
Note that some of the state quantities collected by the collection unit 44 may be transmitted to the management device 14 via the first notification unit 47 in real time.
[0037]
Further, the monitoring function 41 and / or the diagnosis function 42 are not limited to the arrangement mode of the embodiment, and may be mounted on a function block (not shown) of the field device 25 of the field bus communication type, or constitute the management device 14. It is also possible to implement the present invention on a computer or a computer distributed in another place. In particular, when the monitoring function 41 and / or the diagnosis function 42 are mounted on the function block, more diverse diagnosis can be performed. The “field bus” is a digital communication protocol for connecting field devices to each other and a field device and a host system, and includes, for example, Foundation Fieldbus, PROFIBUS, HART, and Brain.
[0038]
Further, in the above-described embodiment, one state quantity is detected by one field device 25. However, the present invention is not limited to this. The field device 25 may collect some or all of the state quantities. According to this, the number of configuration of the field devices 25 in the target system 12 can be minimized, and the equipment of the target system 12 can be reduced in size.
[0039]
Further, the automation system to which the present invention is applied is not limited to the process automation of the above embodiment, and other automation systems can be adopted. In short, the type and configuration of the system are not limited, as long as a configuration that can detect an abnormality of the automation system based on the effective utilization of energy in the automation system is adopted.
[0040]
In addition, each configuration in the present invention is not limited to the illustrated configuration example, and various changes can be made as long as substantially the same operation is achieved.
[0041]
【The invention's effect】
As described above, according to the present invention, when detecting an abnormality in an automation system, it is not necessary to constantly compare all state quantities with normal values, and it is possible to detect an abnormality in the automation system with a small amount of data. it can.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a diagnosis system to which an abnormality detection device according to an embodiment is applied.
FIG. 2 is a schematic configuration diagram showing details of an automation system that is a target of the diagnostic system.
FIG. 3 is a flowchart showing an abnormality detection procedure by the diagnostic system.
[Explanation of symbols]
10 Diagnostic system 12 Target system (automation system)
13 Abnormality detection device 25 Field device 41 Monitoring function 42 Diagnosis function 44 Collection means 45 Calculation means 46 Comparison determination means 47 First notification means (monitoring state notification means)
51 cause identification means 52 first notification means (diagnosis result notification means)

Claims (8)

In a device that detects abnormalities in a given automation system,
An abnormality detection device for an automation system, wherein the abnormality is detectably provided based on an effective use degree of energy in the automation system. A monitoring function for monitoring the operation state of the automation system, and a diagnostic function for diagnosing the automation system based on a monitoring result by the monitoring function,
The monitoring function is a computing unit that computes the effective utilization of the energy from a predetermined state quantity in the automation system, and compares the computed effective utilization of the energy with a normal value, so that the effective utilization of the energy is A comparison determining unit that determines that the abnormality may have occurred when the value is lower than the normal value,
The diagnostic function includes a cause for determining the cause of the abnormality from the state quantity or the state quantity necessary for specifying the cause when the comparison determining means determines that the abnormality may have occurred. 2. The abnormality detection device for an automation system according to claim 1, further comprising a specifying unit. 3. The abnormality detection device for an automation system according to claim 2, wherein the monitoring function includes a collection unit that measures and collects a predetermined state amount in the automation system. The apparatus further comprises a monitoring state notifying unit that notifies the cause specifying unit of the execution of the diagnosis when the comparison determining unit determines that the abnormality may have occurred. Item 4. The abnormality detection device for an automation system according to item 2 or 3. 5. The abnormality detecting apparatus for an automation system according to claim 2, further comprising a diagnosis result notifying unit for notifying a predetermined device of a diagnosis result by said cause specifying unit. The abnormality detection device for an automation system according to any one of claims 2 to 5, wherein the monitoring function and / or the diagnosis function are implemented in a function block of a field device. The automation system according to any one of claims 2 to 6, wherein a part or all of the state quantity is collected by a multi-variable field device capable of detecting a plurality of state quantities with one device. Anomaly detection device. In a method for detecting an abnormality of a predetermined automation system using a computer,
Calculate the effective utilization of energy in the automation system, and when the effective utilization of the energy falls below a predetermined normal value, determine that there is a possibility that an abnormality has occurred in the automation system. An abnormality detection method for an automation system, wherein a state quantity corresponding to the cause of the abnormality is sequentially investigated to identify the cause of the abnormality.

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