JP2016099809A - Plant monitoring control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plant monitoring control system, and automatically cease instrumentation control when instrumentation equipment that is an object of stoppage is inspected.SOLUTION: A plant monitoring control system includes plant equipment, a process control unit, and a monitoring unit. When processing of an instrumentation instruction is initiated, the process control unit extracts a loop tag table associated with an address of a measured value input from among plural second loop tag tables, and discriminates a state of a stoppage status for the extracted loop tag table. If the stoppage status is on, the process control unit decides whether instrumentation control is performed in a cascaded mode or automatic mode. If the process control unit decides that the instrumentation control is performed in the cascaded mode or automatic mode, the process control unit switches the instrumentation control to a manual mode.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a supervisory control system, and more particularly to a plant supervisory control system having a function of preventing malfunctions of instrumentation control when checking instrumentation equipment of a plant.

  In a monitoring control system such as a water treatment plant, instrumentation equipment (or plant equipment) is regularly inspected (see, for example, Patent Documents 1 to 6). During inspection, by setting the instrumentation equipment to be suspended from the monitoring device to the process control device, it is possible to set an arbitrary measurement value so that alarms are not suppressed from the process control device to the monitoring device and abnormal measurement values are not recorded. (For example, see Patent Documents 1 and 2). In addition, at the time of pause setting, the instrumentation device to be paused cannot be operated from the screen of the monitoring device (see, for example, Patent Document 3). In addition, it is possible to switch between display and input by changing the monitoring mode between normal operation and regular inspection (see, for example, Patent Document 4). Further, the normal device and the maintenance registered device are distinguished from each other and a message is output (see, for example, Patent Document 5).

JP 2012-164250 A JP-A-8-30320 JP 2012-93900 A Japanese Patent Laid-Open No. 9-6428 JP-A-6-208694 JP 2010-257310 A

  The plant monitoring and control system includes a monitoring device, a process control device, an engineering device, plant equipment, and the like. The monitoring device and the process control device are connected via a network, and a program designed and manufactured by an engineering device based on the specifications of the plant is transferred to the process control device via a communication cable. The state and failure of the plant equipment are transmitted as digital signals, and analog signals are transmitted from the sensors of the plant equipment. The process control device takes in the digital signal or analog signal from the signal line, transmits the signal to the monitoring device via the network, performs sequence control and instrumentation control, and outputs control to the signal line.

  Inside the process control device, a sequence instruction group for executing sequence control, a numerical operation instruction group for executing numerical operation, and an instrumentation instruction for executing instrumentation control are provided. Further, the process control device is mounted with an application program storage memory for storing a program transferred from the engineering device to the process control device, and an internal memory used for executing the application program. Instrumentation control stores necessary information in the loop tag table and performs calculations. The CPU executes the application program stored in the application program storage memory while referring to various instruction groups.

Next, an instrumentation function in the plant monitoring control system will be described. The process control apparatus includes a loop tag table configured by a plurality of pieces of information by one instrumentation control. In the plant monitoring control system, instrumentation control (PID control) is implemented in a process control device.
Instrumentation control uses MV (Manipulated) from the difference between SV (Setting Value) and PV (Process Value) and parameters such as P (Proportional), I (Integral), and D (Derivative) set in the loop tag table. Feedback control that increases or decreases (Value) and eliminates the difference between PV and SV is known.

  In the instrumentation control (PID control), the instrumentation control is automatically calculated in the automatic mode (AUT) or the cascade mode (CAS), and in the manual mode (MAN), the automatic calculation is not performed and the MV is manually operated from the monitoring device. Perform the operation. When the instrumentation device corresponding to the measurement value used in instrumentation control is set to be paused, the measurement value does not change. If there is a difference between the measurement value (PV) and the set value (SV), the difference remains and the manipulated variable (MV ) Continue to increase or decrease. In cascade control, the control loop is doubled, the loop that feeds back the control amount that is the original purpose is the “master loop” or “major loop”, and the loop that is configured inside the master loop is the “slave loop” Or “minor loop”.

  In the plant monitoring and control system configured as described above, in order to use the signal for instrumentation control when inspecting the instrumentation object to be suspended, the instrumentation control needs to be set to the MAN mode. If this operation is forgotten, the control output continues to be output in the direction of the maximum value or the minimum value, and erroneous output is made to the plant equipment. The present invention has been made to solve such a problem, and the instrumentation control is automatically performed when the measurement control captures a signal indicating that the measurement signal used by the instrumentation control is paused. The purpose is to stop.

  In order to solve the above problems, a plant monitoring control system according to the present invention includes a plant device that transmits a measurement signal, a first loop tag memory, and a plurality of second loop tag memories, and a measurement transmitted from the plant device. A process control device for performing instrumentation control of plant equipment based on a signal and a parameter stored in the first loop tag memory; and a pause of a plurality of second loop tag tables connected to the process control device via a network A monitoring device that sets the status to on or off, and when the process control device starts processing the instrumentation command, the process control device generates a loop tag table corresponding to the address of the measurement value input from the plurality of second loop tag tables. Extract, determine the status of the pause status for the extracted loop tag table, and When the status is ON, it is determined whether the instrumentation control is operating in the cascade mode or the automatic mode. If it is determined that the instrumentation control is operating in the cascade mode or the automatic mode, the instrumentation control is shifted to the manual mode. .

  According to the said structure, instrumentation control can be automatically stopped because measurement control takes in the signal which shows that the measurement signal which instrumentation control uses has stopped.

It is the schematic which shows the structure of the plant monitoring control system by embodiment. 2 is a block diagram illustrating an internal configuration of a process control apparatus according to Embodiment 1. FIG. It is a block diagram showing the internal structure of the plant monitoring control system by Embodiment 1. It is a block diagram showing the instrumentation function in the plant monitoring control system by Embodiment 1. FIG. 6 is a flowchart showing a processing procedure in instrumentation control according to the first embodiment. It is a block diagram showing the internal structure of the plant monitoring control system by Embodiment 2. It is a block diagram showing the instrumentation function in the plant monitoring control system by Embodiment 2. FIG. 10 is a flowchart showing a processing procedure in instrumentation control according to the second embodiment. FIG. 10 is a block diagram illustrating an instrumentation function in a plant monitoring control system according to a third embodiment. FIG. 10 is a flowchart showing a processing procedure in instrumentation control according to the third embodiment. It is a block diagram showing the internal structure of the plant monitoring control system by Embodiment 4. FIG. 10 is a flowchart showing a processing procedure in instrumentation control according to the fourth embodiment. FIG. 10 is a block diagram illustrating an internal configuration of a process control apparatus according to a fifth embodiment. It is a block diagram showing the internal structure of the plant monitoring control system by Embodiment 5. FIG. 10 is a flowchart illustrating a processing procedure in instrumentation control according to the fifth embodiment.

  A plant monitoring control system according to an embodiment of the present invention will be described below with reference to the drawings. In each figure, the same or similar components are denoted by the same reference numerals, and the sizes and scales of the corresponding components are independent. For example, when the same components that are not changed are illustrated in cross-sectional views in which a part of the configuration is changed, the sizes and scales of the same components may be different. In addition, the configuration of the plant monitoring control system actually includes a plurality of members, but in order to simplify the explanation, only the parts necessary for the explanation are shown and the other parts are omitted.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a plant monitoring control system 100. The plant monitoring control system 100 includes a monitoring device 5, a process control device 1, an engineering device 8, a plant device 6 (instrumentation device), and the like. The monitoring device 5 and the process control device 1 are connected via a network 7. A program designed and manufactured by the engineering device 8 based on the specifications of the plant is transferred to the process control device 1 via the communication cable 105. The process control device 1 takes in digital signals and analog signals from the signal line 107 and transmits these signals to the monitoring device 5 via the network 7. A digital signal transmitted to the process control device 1 via the signal line 107 represents a state or failure of the plant equipment 6. An analog signal transmitted to the process control device 1 via the signal line 107 is obtained from a sensor of the plant equipment 6. Further, the process control apparatus 1 performs sequence control and instrumentation control, and outputs a control output to the signal line 107.

  FIG. 2 is a block diagram showing the internal configuration of the process control apparatus 1. The process control apparatus 1 is equipped with an application program storage memory 13, an internal memory 14, and a loop tag memory 17. The application program storage memory 13 is used to store a program transferred from the engineering device 8 to the process control device 1. The internal memory 14 is used for executing application programs. In addition, the process control device 1 includes various program instruction groups 16. The program instruction group 16 includes a sequence instruction 16a for executing sequence control, a numerical operation instruction 16b for executing numerical operation, an instrumentation instruction 16c for executing instrumentation control, and the like. A CPU (Central Processing Unit) 15 executes an application program stored in the application program storage memory 13 while referring to various instruction groups.

  FIG. 3 is a block diagram showing the internal configuration of the process control apparatus according to the embodiment of the present invention. The process control apparatus 1 includes a CPU unit 2, an I / O (Input / Output) unit 3, and a network unit 4. The CPU unit 2 includes an application program 13, an internal memory 14, a CPU 15, a program instruction group 16, and a loop tag memory 17. The application program 13 includes programs such as a sequence control 11 and an instrumentation control 12 created based on the specifications for each plant. The internal memory 14 is used by the monitoring device 5 and the application program 13 for reading and writing. The program instruction group 16 includes a sequence instruction 16a, a numerical instruction 16b, an instrumentation instruction 16c, and the like. The loop tag memory 17 stores a plurality of loop tag tables (loop tag tables A and B). Information necessary for instrumentation control (PID control) is stored in a loop tag table A 17 a set in the loop tag memory 17. The instrumentation control 12 includes an instrumentation program 20 that only monitors measurement signals and an instrumentation program 21 that performs instrumentation control. The CPU 15 controls the CPU unit 2 and executes the application program 13 such as the sequence control 11 and the instrumentation control 12 with reference to the program instruction group 16.

  In the present embodiment, the loop tag memory 17 stores a loop tag table A (first loop tag table) 17a and a loop tag table B (second loop tag table) 17b. The loop tag memory 17 uses one loop tag table for one measurement signal to be monitored (or one instrumentation control). Although the loop tag table B17b is drawn as a single unit in the drawing, there may be a plurality of loop tag tables B17b. The loop tag table includes a plurality of pieces of information, and a plurality of parameters are set for measurement control and instrumentation control. These parameters are displayed on the parameter tuning screen of the monitoring device 5 via the network 7, and these parameters can be changed from this screen. As the measurement signal, a digital signal representing a state and a failure is transmitted from the plant equipment 6, and an analog signal is transmitted from the sensor of the plant equipment. The I / O unit 3 inputs a digital signal or an analog signal from the plant device 6 and transmits a control output constructed by the application program 13 to the plant device 6. The network unit 4 exchanges data such as a monitoring signal, a failure signal, a status signal, a control signal, and a setting signal with the monitoring device 5 via the network 7.

FIG. 4 is a block diagram showing an instrumentation function in the plant monitoring control system, and the operation of the plant monitoring control system will be described based on this figure. In the plant monitoring control system, PID control (Proportional-Integral-Derivative Controller) for controlling the plant equipment 6 (instrumentation equipment) is mounted. In this figure, a flow meter 6a and a pump 6c are displayed as specific examples of plant equipment. As instrumentation control (PID control), the difference between SV (setting value: Setting Value) and PV (measurement value: Process Value), and P (proportional constant: Proportional), I (integral constant: set in the loop tag table) The feedback control is performed to increase or decrease MV (manipulated value) from parameters such as Integral) and D (differential constant: Derivative) to eliminate the difference between the measured value (PV) and the set value (SV). The process control device 1 includes a loop tag table A17a and a loop tag table B17b for one instrumentation control. Each of the loop tag tables A and B includes a plurality of pieces of information.

  The parameters of the loop tag table A17a include PV and ALM for measurement control, SV, MV, PV, P, I, D, ALM, etc. for instrumentation control. ALM (alarm information) includes an upper limit alarm and a lower limit alarm. The parameters of the loop tag table B17b include a pause status 22 in addition to PV and ALM for measurement control. In the instrumentation control, the instrumentation control is automatically calculated in the automatic mode (AUT) or the cascade mode (CAS), and in the manual mode (MAN), the automatic operation is not performed and the MV is manually operated from the monitoring device 5. . When the instrumentation device (or plant device) corresponding to or corresponding to the measurement value used in the instrumentation control is set to dormant, the measurement value will not change, and if there is a difference between the measurement value (PV) and the set value (SV), the difference will be Continue to remain and continue to increase or decrease the manipulated variable (MV). The suspension status 22 of the loop tag table is turned ON by performing the suspension operation 5a on the device to be suspended from the monitoring device 5, and the suspension status 22 is turned OFF by releasing the suspension operation 5a.

  The CPU unit 2 inputs measurement signals from the plant equipment 6 from the I / O unit 3. When the measurement signal is not paused 5a, the measurement program 20 performs alarm monitoring of upper and lower limit abnormalities and conversion of engineering values, and sends information such as ALM and PV to the monitoring device 5 via one or more loop tag tables B17b. Send. When there is a pause operation 5a, alarm suppression and PV are held at an arbitrary value set from the monitoring device 5. The instrumentation program 21 performs instrumentation control (PID control) using the PV calculated by the measurement program 20. The CPU unit 2 extracts the loop tag table storing the PV from the PV address designated as the input of the instrumentation command from the loop tag memory 17, and is in a dormant state with reference to the dormant status 22 of the loop tag table. Check whether or not. If it is in a dormant state, that is, if the dormant status 22 is on, the instrumentation control is set to the MAN mode and the automatic control is stopped.

  Next, the instrumentation command of the process control apparatus 1 will be described with reference to the flowchart of FIG. The application program 13 is executed at a constant cycle. When the instrumentation instruction 16c is executed, it is determined whether the PV (measurement value) address used in the instruction is the PV of the loop tag table (step S1). If it is the address of the loop tag table, the corresponding or corresponding loop tag table is extracted (step S2), and the sleep status of the loop tag table is confirmed by the sleep status 22 (step S3). Instrumentation control is continued if it is not in the dormant state (the dormant status is on) (step S4), but if it is in the dormant state and control is being performed in AUT and CAS, the mode is changed to manual mode (MAN) ( Step S5), the control is stopped.

  In the present embodiment, the instrumentation instruction automatically determines whether or not the measurement signal used in the instrumentation program is in a pause state. Since the instrumentation control is changed to the manual mode and the control is stopped in the inactive state, erroneous control of the instrumentation program can be prevented, and a highly reliable apparatus can be obtained.

Embodiment 2. FIG.
In the first embodiment, the case where the instrumentation command stops the automatic control by confirming the pause state of the measurement signal has been described. FIG. 6 is a block diagram showing the internal configuration of the process control apparatus according to the second embodiment of the present invention. The instrumentation control 12 includes a measurement program 20a and a measurement program 20b. The loop tag memory 17 includes a loop tag table A (first loop tag table) 17a, a loop tag table B (second loop tag table) 17b, and a loop tag table C (second loop tag table) 17c.

  FIG. 7 is a block diagram showing an instrumentation function in the plant monitoring control system according to the present embodiment. The loop tag table B17b is linked with the measurement program 20a. The loop tag table C17c is linked with the measurement program 20b. The TAG 23 of the loop tag table A17a can register a plurality of tag IDs (Identifications) of the loop tag table of measurement signals related to instrumentation control. In the present embodiment, since the TAG 23 is provided in the loop tag table A17a, the same function as in the first embodiment can be realized even when a plurality of measurement signals are used as PV for instrumentation control. In the figure, the sum of measured values of two flow rates is PV for instrumentation control. The measurement program 20a and the measurement program 20b correspond to the flow meter 6a and the flow meter 6b, respectively.

  Next, instrumentation instructions of the process control apparatus 1 will be described with reference to the flowchart of FIG. The instrumentation command is executed at a constant cycle, and it is determined whether or not the tag ID of the related loop tag table is registered in the TAG 23 of the loop tag table A used in the control (step S21). If registered, the loop tag table is extracted (step S22), and it is confirmed whether any of the loop tag tables is in a dormant state (step S23). If the instrumentation control is not carried out (step S24), the control mode is changed to MAN (step S25) and the control is stopped.

Embodiment 3 FIG.
In the first and second embodiments, the case has been described in which the automatic control is stopped by the instrumentation instruction determining the pause state of the measurement signal. FIG. 9 is a block diagram showing the internal configuration of the process control apparatus according to Embodiment 3 of the present invention. Since the alarm status indicating automatic stop is provided in the ALM 24 of the loop tag table A when the instrumentation control is stopped as shown in the figure, an alarm (automatic stop 5b) is notified to the monitoring device 5. And maintainability can be improved.

  Next, instrumentation instructions of the process control apparatus 1 will be described with reference to the flowchart of FIG. Steps S41 to S45 are as shown in FIG. 5 of the first embodiment. After the instrumentation control shifts to the manual mode, the automatic stop status of the ALM 24 in the loop tag table A17a is turned on (step S46). Since the monitoring device 5 detects that the automatic stop status of the loop tag table is turned on via the network 7, it can notify the user.

Embodiment 4 FIG.
In the third embodiment, the case where an alarm is notified to the monitoring device 5 has been described. FIG. 11 is a block diagram showing the internal configuration of a process control apparatus according to Embodiment 4 of the present invention. As shown in the figure, since the process control device 1 is provided with the LED 25 (Light Emitting Diode), the process control device 1 can confirm the stop of the instrumentation control and can improve the maintainability. .

  Next, an instrumentation instruction of the process control apparatus 1 will be described with reference to a flowchart of FIG. Steps S51 to S55 are as shown in FIG. 5 of the first embodiment, and then the LED 25 is turned on (step S56).

Embodiment 5 FIG.
In the first and second embodiments, the case has been described where automatic control is stopped by determining the pause state of the measurement signal. FIG. 13 is a block diagram showing the internal configuration of the process control apparatus according to Embodiment 5 of the present invention. The monitoring device 5 can request a confirmation operation via the network 7 to the CPU 15 of the process control device 1. The engineering device 8 transmits a signal requesting a confirmation operation to the CPU 15 of the process control device 1 via the communication cable 105. The process control device 1 includes an operation switch 9 for transmitting a confirmation operation.

  FIG. 14 is a block diagram showing an instrumentation function in the plant monitoring control system. Since the monitoring device 5 or the engineering device 8 or the operation switch 9 is provided with a function for confirming in advance whether the function of stopping the automatic control works, it is possible to prevent erroneous control of the instrumentation program and to improve reliability. Can be obtained. Further, since the alarm status indicating the automatic stop is provided in the ALM 24 of the loop tag table A17a, the alarm can be notified to the monitoring device 5, and the maintainability can be improved.

  Next, a method for confirming the implementation of the function for stopping automatic control of the process control apparatus will be described with reference to the flowchart of FIG. When the process control device 1 receives a confirmation operation from the operation switch 9 of the monitoring device 5, the engineering device 8, or the process control device 1 (step S31), it is confirmed whether an instrumentation command (instrumentation control) is implemented in the application program. (Step S32). If an instrumentation command is implemented, it is confirmed whether the input address for instrumentation control is PV (or its address) (step S33). If the input address is not PV, that is, if the input address does not match the PV address, it is confirmed whether the tag ID is registered in the TAG 23 of the loop tag table A (step S34).

  If the tag ID is not registered, the automatic stop status of the ALM 24 in the loop tag table A is turned ON (step S35). If the tag ID is registered in the TAG 23 in step S34, it is checked whether there is a loop tag table for the registered measurement signal (step S36). If there is no loop tag table, the automatic stop status of the ALM 24 in the loop tag table A is checked. Is turned ON (step S35).

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

1 process control device, 5 monitoring device, 6 plant equipment, 7 network, 8 engineering device, 100 plant monitoring control system, 105 communication cable, 107 signal line

Claims (6)

Plant equipment that transmits measurement signals;
Instrumentation of the plant equipment based on a measurement signal transmitted from the plant equipment and parameters stored in the first loop tag memory, having a first loop tag memory and a plurality of second loop tag memories A process control device for controlling,
A monitoring device that is connected to the process control device via a network and that sets a dormancy status of the plurality of second loop tag tables to ON or OFF,
When the process control device starts processing an instrumentation instruction,
Extracting a loop tag table corresponding to an address of a measurement value input from the plurality of second loop tag tables;
Determine the status of the dormancy status for this extracted loop tag table,
If the dormant status is on, determine if instrumentation control is operating in cascade or automatic mode,
A plant supervisory control system characterized in that if it is determined that the system is operating in a cascade mode or an automatic mode, the instrumentation control is shifted to a manual mode.   The plant monitoring control system according to claim 1, wherein a plurality of tag IDs of measurement signals are registered in the first loop tag table.   The process control apparatus extracts a loop tag table corresponding to a tag ID registered in the first loop tag table from the plurality of second loop tag tables, and the sleep status of the extracted loop tag table is determined. The plant monitoring control system according to claim 2, wherein the state is determined.   The plant monitoring control system according to claim 1, wherein the process control device turns on an automatic stop status of the first loop tag table when instrumentation control shifts to a manual mode.   The plant monitoring control system according to claim 1, wherein the process control device turns on the light emitting diode when the instrumentation control shifts to the manual mode. Plant equipment that transmits measurement signals;
The plant device has a first loop tag memory, a plurality of second loop tag memories, and an operation switch, and is based on a measurement signal transmitted from the plant device and a parameter stored in the first loop tag memory. A process control device for performing instrumentation control of
An engineering device that creates a measurement program and transmits the created measurement program to the process control device via a communication cable;
A monitoring device that is connected to the process control device via a network and that sets a dormancy status of the plurality of second loop tag tables to ON or OFF,
When the process control device receives a confirmation operation from the monitoring device, the engineering device or the operation switch, it determines whether instrumentation control is implemented,
If it is implemented, check whether the instrumentation control input address is a measured value,
If the input address is not a measured value, check whether the tag ID is registered in the first loop tag memory,
A plant monitoring control system, wherein when the tag ID is not registered, the automatic stop status of the first loop tag table is turned on.

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