JP2016218939A - Plant monitoring control system, and access management method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that, since a configuration in which multiple CPU modules access one I/O module was not assumed, actions of each individual CPU had to be regulated.SOLUTION: A control device is equipped with multiple control modules that output control commands generated on the basis of operation commands and multiple input/output modules that output control commands received from the control modules to an object of control and input data inputted from the object of control to the control modules. The control modules access other control modules and input/output modules in accordance with an access management table in which other accessible control modules and input/output modules are prescribed.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a plant monitoring control system and an access management method for monitoring and controlling a power plant, for example.

  Generally, in a power plant, a plant monitoring control system is constructed in which computers such as a plant monitoring device and a maintenance tool are arranged in a central control room. The plant monitoring device and the maintenance tool are connected to a control device such as a boiler control device or a turbine control device via a network. Various controlled objects (valves, pumps, etc.) are operated based on an operation command from the plant monitoring device or a control command from the control device. In the conventional control device, one I / O (Input / Output) module is provided for one CPU (Central Processing Unit) module, and a plurality of controlled devices are provided via this I / O module. Objects (eg, sensors, pumps) were connected to the CPU module. Since the operation of the controlled object is controlled by the CPU module connected to the I / O network, the operation is not controlled by another CPU module not connected to the I / O network.

  As such a plant control device, for example, a technique disclosed in Patent Document 1 is known. Patent Document 1 states that “a control device receives a command from an operation monitoring device via a network, and a CPU calculates a control command based on the command and a measurement value input from a measurement device, In contrast, a control command is output. "

JP 2010-244424 A

  Patent Document 1 described above describes that a control device or a measurement device that controls each CPU is determined. However, when only a single CPU controls the operation of the control device or the measurement device, the plant monitoring device cannot acquire the data of the control device or the measurement device when the CPU is stopped. Therefore, in recent years, the reliability of the network has increased, high-speed communication has become possible, and it is necessary to utilize the calculation performance of the CPU module, so control devices or measuring devices can be controlled using multiple CPU modules. Technology to do this has been studied.

  However, in order for a plurality of CPU modules to be connected in a network so as to share the I / O module, it is necessary to define processing when each CPU module accesses the I / O module.

  The present invention has been made in view of such a situation, and an object thereof is to specify an access operation to an I / O module performed using a plurality of CPU modules.

A control device according to the present invention outputs a control command received from a control module and a plurality of control modules that output a control command for the controlled object to the controlled object provided in the plant, and is input from the controlled object A plurality of input / output modules for transmitting data to the control module.
Then, the control module accesses the other control module and the input / output module according to the access management table in which the other control module and the input / output module that can be accessed are defined.

According to the present invention, for example, even if one control module is stopped, other control modules can access the input / output module, so that the redundancy of the plant monitoring control system can be increased.
Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is a block diagram which shows the structural example of the plant monitoring control system which concerns on the example of 1 embodiment of this invention. It is a block diagram which shows the hardware structural example of the computer which concerns on the example of 1 embodiment of this invention. It is explanatory drawing which shows the structural example of the access management table which concerns on the example of 1 embodiment of this invention. It is a sequence diagram which shows an example of the process which the CPU module and I / O module which concern on one embodiment of this invention perform. It is explanatory drawing which shows the logic which switches a time master when abnormality arises in the time master which concerns on the example of 1 embodiment of this invention. FIG. 5A shows a state in which the first CPU is the time master and each CPU module is operating normally. FIG. 5B shows a state after three calculation cycles after the first CPU stops. FIG. 5C shows a state when the second CPU is promoted to the time master. It is a sequence diagram which shows the example of the switching process of the time master which concerns on one embodiment of this invention. It is a block diagram which shows the structural example of the plant monitoring control system which concerns on the modification of one embodiment of this invention.

  Hereinafter, a plant monitoring control system according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same function or configuration are denoted by the same reference numerals, and redundant description is omitted.

FIG. 1 is a block diagram illustrating a configuration example of the plant monitoring control system 1.
The plant monitoring control system 1 includes a plant monitoring device 3, a maintenance tool 4, a CPU network 5, a plurality of CPU modules 6 (an example of a control module), an I / O network 7, and a plurality of I / O modules 8 (input / output modules). An example). In the following description, the plurality of CPU modules 6 are referred to as “CPU module group”, and the plurality of I / O modules 8 are referred to as “I / O module group”. The CPU module group and the I / O module group are collectively referred to as a “control device”, and an object to which the control device outputs a control command is referred to as a “controlled object”.

  In the central control room 2, a plant monitoring device 3 and a maintenance tool 4 are installed. The plant monitoring device 3 and the maintenance tool 4 are each connected to a CPU module group via a CPU network 5. The CPU module group and the I / O module group are connected via the I / O network 7.

  The plant monitoring device 3 is a human machine interface device having an operation / monitoring function necessary for plant operation. The plant monitoring device 3 outputs an operation command to the controlled object to the CPU module group of the control device based on the operation of the operator. Further, the plant monitoring device 3 displays the state of the plant (plant information) based on data from the control device on a display device such as a CRT (Cathode Ray Tube), a liquid crystal display, etc. Provide control information and output guidance.

  The maintenance tool 4 is used for performing maintenance work on the control device. The maintenance tool 4 creates logic for controlling the plant and loads these logics into the control device. In addition, the maintenance tool 4 performs maintenance operations such as various settings of the control device, logic editing, the calculation process of the control device and the parameters of the calculation elements, and tuning of the parameters of the calculation elements.

The control device takes in data representing the state of the plant from a controlled object provided in the plant, and outputs a control command for the controlled object based on an operation command for the plant.
Here, each CPU module 6 of the CPU module group calculates a control command for the controlled object of the power plant based on the operation command received from the plant monitoring device 3, and uses the generated control command as a specific I / O module 8. Output to. The calculation and generation of the control command is, for example, digital data (measured value) obtained by converting an electrical signal representing the state of the power plant, which is taken in by the I / O module 8 from the controlled object, with an A / D converter, or plant monitoring This is performed based on an operation command from the device 3. The plurality of CPU modules 6 provided in the CPU module group are identified as a first CPU, a second CPU, a third CPU,. The first CPU, the second CPU, the third CPU,... Are connected to the I / O module 8 via the I / O network 7.

  Each I / O module 8 in the I / O module group converts a control command calculated by the CPU module 6 into an electrical signal by a D / A converter, outputs the electrical signal to the controlled object, and operates the controlled object. Further, the I / O module 8 inputs data input from the controlled object to the CPU module 6. In the power plant, a plurality of CPU modules 6 and I / O modules 8 are prepared according to controlled objects such as boilers and turbines.

  The I / O module 8 is identified as a first DI, a second DI, a first AI, a second AI,. In FIG. 1, the I / O module 8 to which digital data is input is described as “DI”, and the I / O module 8 that outputs digital data is described as “DO”. The I / O module 8 to which analog data is input is described as “AI”, and the I / O module 8 that outputs analog data is described as “AO”.

  All CPU modules 6 and I / O modules 8 are set with uniquely identifiable station numbers (an example of identification information). For example, # 800 is assigned to the first CPU, and # 801 is set to the second CPU. Also, # 000 is assigned to the first DI, and # 001 is set to the second DI. The station number is set by a toggle switch or the like mounted on each CPU module 6 or I / O module 8. An IP (Internet Protocol) address assigned to each module as identification information by a DHCP (Dynamic Host Configuration Protocol) server (not shown) may be used instead of the station number.

  Controlled objects include, for example, a switch 9a, a sensor 9b, a pump 9c, and a valve 9d. The controlled object is connected to a specific I / O module 8. For example, a switch 9a is connected to the first DI, a sensor 9b is connected to the second AI, a pump 9c is connected to the first DO, and a valve 9d is connected to the first AO.

<Example of computer hardware configuration>
Next, the hardware configuration of the computer 10 constituting the plant monitoring device 3 and the maintenance tool 4 will be described.
FIG. 2 is a block diagram illustrating a hardware configuration example of the computer 10.

  The computer 10 is hardware used as a so-called computer. The computer 10 includes a CPU 11, a ROM (Read Only Memory) 12, and a RAM (Random Access Memory) 13 connected to a bus 14. The computer 10 further includes a display unit 15, an operation unit 16, a nonvolatile storage 17, and a network interface 18.

  The CPU 11 reads out the program code of the software that realizes each function according to the present embodiment from the ROM 12 and executes it. In the RAM 13, variables, parameters, and the like generated during the arithmetic processing are temporarily written. The display unit 15 is, for example, a liquid crystal display monitor, and displays the results of processing performed by the computer 10 to the operator. For example, a keyboard, a mouse, or the like is used as the operation unit 16, and an operator can perform predetermined operation inputs and instructions.

  Examples of the non-volatile storage 17 include a hard disk drive (HDD), a solid state drive (SSD), a flexible disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, and a non-volatile memory card. Used. In addition to the OS (Operating System) and various parameters, the nonvolatile storage 17 stores a program for causing the computer 10 to function. As the network interface 18, for example, a NIC (Network Interface Card) or the like is used, and various types of data can be transmitted / received via the CPU network 5 to which terminals are connected.

  FIG. 3 is a table configuration diagram of the access management tables 21 to 23. FIG. 3 shows an example in which the CPU module group includes the CPU modules 6 of the first CPU to the third CPU.

  Each CPU module 6 includes an access management table in which other accessible CPU modules 6 and I / O modules 8 are defined, and accesses the other CPU modules 6 and I / O modules 8 according to the access management table. . For example, the first CPU includes an access management table 21, the second CPU includes an access management table 22, and the third CPU includes an access management table 23. The access management tables 21 to 23 are stored in the built-in memories of the first CPU to the third CPU.

  The access management table 21 stores the station number of the CPU module 6 (second CPU, third CPU) accessible by the first CPU and the station number of the I / O module 8. Therefore, the first CPU can access the CPU module 6 and the I / O module 8 corresponding to the station number stored in the access management table 21. For example, the first CPU requests data from the second CPU stored in the access management table 21 and whose station number is # 801, and receives data from the second CPU. Next, the first CPU requests data from the third CPU whose station number is # 802 and receives data from the third CPU. Similarly, the first CPU receives input data from the first DI whose station number is # 000, and receives input data from the first AI whose station number is # 002. The first CPU transmits output data to the first DO whose station number is # 004 and transmits output data to the first AO whose station number is # 007.

  Further, the second CPU can access other CPU modules 6 and I / O modules 8 based on the station numbers stored in the access management table 22. The third CPU can access other CPU modules 6 and I / O modules 8 based on the station number stored in the access management table 23. The access that each CPU module 6 makes to other CPU modules 6 and I / O modules 8 is repeated periodically.

Here, processing performed by the CPU module 6 and the I / O module 8 will be described.
FIG. 4 is a sequence diagram illustrating an example of processing performed by the CPU module 6 and the I / O module 8.

  First, processing when the output I / O module 8 having the same station number is stored in the access management table of different CPU modules 6 will be described. In this case, different CPU modules 6 transmit different control commands to the same I / O module 8 for output. For example, in the access management table 22 of the second CPU and the access management table 23 of the third CPU, the second AO whose station number is # 008 is stored as the transmission destination of the control command. In this case, if the third CPU transmits data to the second AO after the second CPU transmits data to the second AO, the controlled object may operate unintentionally.

  Therefore, the I / O module 8 stores in the built-in memory the station number of the CPU module 6 that has been initialized first. Then, the I / O module 8 permits access from the CPU module 6 identified by the station number stored in the built-in memory, and disallows access from other CPU modules 6 to which other station numbers are allocated. Define the process to

  For example, when the second CPU first initializes the second AO, the second AO stores # 801, which is the station number of the second CPU. Thereafter, the second CPU accesses the second AO (S1). At this time, the second AO determines whether or not the CPU module 6 is the first CPU module initialized by the second CPU (S3). Since the station number of the second CPU is # 801, the second AO determines that the second CPU is the CPU module 6 that was first initialized (YES in S3), and permits access to the second CPU (S4).

  Here, when the third CPU accesses the second AO (S2), the second AO determines that the third CPU is not the module initialized first because the station number of the third CPU is # 802 (NO in S3). The access to the third CPU is not permitted (S5). Thereby, even if a plurality of CPU modules 6 transmit different control commands to one I / O module 8, it is possible to avoid a situation in which the I / O module 8 transmits different control commands to one controlled object. .

  When the CPU module 6 that is permitted to access the output I / O module 8 is set in this way, other CPU modules 6 cannot access the I / O module 8 in the subsequent processing. On the other hand, the input I / O module 8 can be accessed by a plurality of CPU modules 6 to obtain input values. Therefore, the processing when the information set for the I / O module 8 from the CPU module 6 at the initial activation of the I / O module 8 differs among the plurality of CPU modules 6 is defined.

  For example, the input I / O module 8 operates with a range setting of −5 V (0%) to +5 V (100%), and the CPU module 6 that has set the range for this I / O module 8 has −5 V (0 %) To + 5V (100%) is assumed. Then, it is assumed that the other CPU module 6 performs the calculation with a setting of −10 V (0%) to +10 V (100%). At this time, if the value input from the controlled object to the input I / O module 8 is +5 V, the I / O module 8 transmits a value of 100% indicating +5 V to the CPU module 6. However, when the other CPU module 6 receives a value of 100% from the I / O module 8, the other CPU module 6 performs an operation assuming that + 10V is input to the I / O module 8. As described above, the data to be controlled transmitted from the I / O module 8 to the CPU module 6 may be erroneously calculated by other CPU modules 6.

  As shown in FIG. 3, the second CPU and the third CPU use the input value of the second AI whose station number is # 003. However, if the second AI and the third CPU have different second AI range setting values, the next accessed CPU module 6 cannot capture the correct input value. Therefore, if a plurality of CPU modules 6 can access one I / O module 8, the I / O module 8 sends the input value and I / O to the accessing CPU module 6. The range setting value set in the module 8 is transmitted.

  Specifically, the range setting for the second AI is performed by the CPU module 6 that has first accessed the second CPU and the third CPU. The input I / O module 8 responds to the data requests (S1, S2) from the second CPU and the third CPU, the input value acquired from the controlled object for input, and the input I / O module. Both of the range setting values set to 8 are transmitted by unicast (S6).

  The CPU module 6 compares the range setting value received from the I / O module 8 with the range setting value of the CPU module 6 itself (S7). If the range setting values match (YES in S7), the CPU module 6 uses the input value of the controlled object received from the I / O module 8 for the calculation (S8). On the other hand, if the range setting values do not match (NO in S7), the CPU module 6 determines that the input I / O module 8 that has transmitted the range setting values is abnormal, and this input I / O module. The input value received from 8 is not used for the calculation (S9). In addition, although description is abbreviate | omitted also about 3rd CPU, the process similar to step S7-S9 is performed.

Next, switching of the time master will be described.
FIG. 5 is an explanatory diagram showing logic for switching the time master when an abnormality occurs in the CPU module 6 serving as the time master.
FIG. 6 is a sequence diagram illustrating an example of a time master switching process.

  Conventionally, only one CPU module 6 is connected to a plurality of I / O modules 8. When the CPU module 6 becomes a time master and the time data is transmitted by broadcast to the connected I / O module 8, the time synchronization between the CPU module 6 and the I / O module 8 is established. However, when a plurality of CPU modules 6 and a plurality of I / O modules 8 are networked, it is necessary to define a process for determining a CPU module 6 that is a time master.

  Therefore, each CPU module 6 acquires a master state and a heartbeat value from other CPU modules 6 according to the access management tables 21 to 23. If the master state is “1”, the CPU module 6 is the time master, and if “0”, the CPU module 6 is not the time master. The heartbeat value is a management value that is incremented by “1” for each calculation cycle in the CPU module 6. The CPU module 6 responds with a heartbeat value when requested by another CPU module 6. Each CPU module 6 recognizes the other CPU module 6 serving as the time master based on the master state acquired from the other CPU module 6 accessed according to the access management table and the update status of the heartbeat value, and the other CPU module. 6 is recognized. That is, if the heartbeat value is not updated for a certain period, an abnormality has occurred in the CPU module 6 in which the heartbeat value is not updated, or the I / O network 7 with this CPU module 6 is disconnected. Indicates.

FIG. 5A shows a state where the first CPU is a time master and each CPU module 6 is operating normally.
The first CPU transmits time master information to the second CPU and the third CPU, and transmits and receives heartbeat values to and from the second CPU and the third CPU (S11). The second CPU and the third CPU receive the time master from the first CPU and transmit / receive a heartbeat value to / from the first CPU (S12).

  The second CPU and the third CPU recognize that the first CPU is the time master because the master state of the first CPU is “1”. Then, the first CPU recognizes that the heartbeat values of the second CPU and the third CPU have been updated. Similarly, the second CPU updates the heartbeat values of the first CPU and the third CPU, and the third CPU recognizes that the heartbeat values of the first CPU and the second CPU are updated.

FIG. 5B shows a state after three calculation cycles after the first CPU stops.
When an abnormality occurs in the first CPU (S13), the first CPU stops. When the first CPU stops, updating of the heartbeat values of the second CPU and the third CPU managed by the first CPU is also stopped. Then, both the second CPU and the third CPU cannot acquire the master state from the first CPU, and the heartbeat value of the first CPU is not updated. For this reason, the second CPU and the third CPU recognize that an abnormality has occurred in the first CPU (S14).

  Here, in order to prevent a plurality of CPU modules 6 from becoming the time master at the same time, each CPU module 6 waits until it is promoted to the time master after determining that there is no CPU module 6 as the time master. Set in advance. For example, if the waiting time is set so that the first CPU waits for 0 seconds, the second CPU waits for 1 second, and the third CPU waits for 2 seconds, the waiting time set for each CPU module 6 is passed and then the time is promoted to the time master. (S15). In FIG. 5B, since the CPU module 6 to be promoted to the time master is determined in the order from the smallest station number, the second CPU having the smallest station number among the second CPU and the third CPU is promoted to the time master.

  FIG. 5C shows a state when the second CPU is promoted to the time master. Since the third CPU recognizes that the second CPU has been promoted to the time master, it does not promote itself to the time master. When the first CPU is restarted, the master state is acquired from the second CPU. For this reason, the first CPU can recognize that the second CPU is the time master.

  According to the plant monitoring control system 1 according to the embodiment described above, each CPU module 6 refers to the access management table, so that it can access other CPU modules 6 and I / O modules 8. Can be grasped. Thereby, for example, even if one CPU module 6 stops, other CPU modules 6 can access the I / O module 8, so that the redundancy of the plant monitoring control system 1 can be increased.

  In the case of the output I / O module 8, the station number of the CPU module 6 in which the output I / O module 8 is first initialized is stored. Then, the output I / O module 8 permits access only to the CPU module 6 having the stored station number, and does not permit access from the CPU module 6 having another station number. For this reason, the output I / O module 8 does not receive different data from different CPU modules 6. The input I / O module 8 transmits data to the CPU module 6 by unicast. For this reason, the CPU module 6 does not receive different data from the input I / O module 8 that is not stored in the access management table.

  Further, when the input I / O module 8 transmits the input value from the controlled object to the CPU module 6, the input I / O module 8 also transmits its own range setting value to the CPU module 6. Then, the CPU module 6 compares the range setting value received from the I / O module 8 with its own range setting value during the arithmetic processing, and determines that the I / O module 8 is abnormal if they do not match. The received input value is not used for calculation. Thereby, even if an input value different from the range setting value managed by the CPU module 6 is received, the arithmetic processing is not erroneously performed.

  Further, the CPU module 6 transmits / receives a time master state and a heartbeat signal (a value added by 1 for each calculation cycle) to / from other CPU modules 6, thereby mutual time master state and survival Can be monitored. Then, the other CPU modules 6 that have detected that there is no time master set the CPU module 6 with the smallest station number as the time master. Thereby, the CPU module 6 can continue the arithmetic processing.

  Moreover, in the plant monitoring control system 1, it is not necessary to provide the I / O module 8 for every CPU module 6 like the past. For this reason, the number of installed I / O modules 8 can be reduced, and the operation cost can be reduced.

[Modification of First Embodiment]
Note that the CPU module 6 (first CPU to third CPU) may have a duplex configuration.
FIG. 7 shows a configuration example of the plant monitoring control system 1A.
The CPU module 6A included in the plant supervisory control system 1A is provided with two first to third CPUs. If the first to third CPUs are duplicated in this way, the CPU module 6A can be operated with one operating system and the other standby system. Thereby, the fault tolerance of the plant monitoring control system 1A can be improved.

  In the embodiment described above, the CPU modules 6 and 6A are given as an example of the control module and the I / O module 8 is given as an example of the input / output module. However, other modules may be used.

Further, the present invention is not limited to the above-described embodiments, and various other application examples and modifications can be taken without departing from the gist of the present invention described in the claims.
For example, the above-described embodiments are detailed and specific descriptions of the configuration of the apparatus and the system in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Absent. In addition, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Is also possible. Moreover, it is also possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.
Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

  DESCRIPTION OF SYMBOLS 1 ... Plant monitoring control system, 2 ... Central control room, 3 ... Plant monitoring apparatus, 4 ... Maintenance tool, 5 ... CPU network, 6 ... CPU module, 7 ... I / O network, 8 ... I / O module, 20 22 ... Access management table

Claims (6)

A control device that takes in data representing the state of the plant from the controlled object provided in the plant and outputs a control command for the controlled object based on an operation command for the plant;
A plant monitoring device that outputs the operation command to the control device and displays the state of the plant based on the data;
The controller is
A plurality of control modules that output the control commands generated based on the operation commands;
A plurality of input / output modules that output the control command received from the control module to the controlled object and input data input from the controlled object to the control module;
The control module accesses another control module and the input / output module according to an access management table in which the other control module and the input / output module that can be accessed are defined. The control module and the input / output module are uniquely identified by identification information,
The input / output module for output stores the identification information of the control module that has been initialized first, permits access to the control module identified by the identification information, and accesses from other control modules The plant monitoring control system according to claim 1. The input / output module transmits an input value to be controlled and a range setting value set in the input / output module to the control module that has requested transmission of data,
The control module receives the control target received from the input / output module when the range setting value received from the input / output module matches the range setting value of the control module. The plant monitoring control system according to claim 2, wherein the target input value is used for calculation. The control module recognizes the other control module serving as the time master based on the master status acquired from the other control module accessed according to the access management table and the update status of the heartbeat value, and performs the other control. The plant monitoring control system according to claim 1, wherein a connection state with a module is recognized. The plant monitoring control according to claim 4, wherein the control module is promoted to a time master after elapse of a waiting time set for each control module when the master state cannot be acquired from another control module. system. A plurality of control modules that output a control command for the controlled object, and the control command received from the control module is output to the controlled object provided in a plant, and data input from the controlled object is the control module A plurality of input / output modules to be transmitted to the control module access management method of the control device comprising:
The control module is
An access management method for accessing another control module and the input / output module according to an access management table in which the other control module and the input / output module that can be accessed are defined.