JP3204279B2 - Control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instrumentation control device having an operator monitoring console, and more particularly to a field control station and a programmable logic controller using a microprocessor, and a transmitter and an operation terminal installed in a plant. And the like, provided with a lower communication bus interface for transmitting signals to and from field devices.

[0002]

2. Description of the Related Art Hitherto, a control device for directly connecting a field control station or a programmable logic controller to a transmitter or an operation terminal for monitoring and operating has been put into practical use. In this case, if the field control station or the programmable logic controller stops abnormally, both the transmitter and the operation terminal will stop. FIG. 5 is a conceptual diagram of the configuration of the control device. The operator monitoring console 1 and the field control station 2 or the programmable logic controller 10 are connected to an upper communication bus 4 (a control or general-purpose LAN).
Connect through. The field control station 2 or the programmable logic controller 10 is connected to the transmitter 7 and the operation terminal 9 installed in a field such as a plant via the lower communication bus 5. The operator operates the transmitter 7 and the operation terminal 9 from the operator monitoring console 1.
Monitor and operate the plant via. Even with such a configuration, if an abnormality occurs in the field control station 2, the programmable logic controller 10, or the like, there is a disadvantage that the plant cannot be operated continuously. Therefore, Field Control Station 2
Has duplicated CPUs and designed redundancy in each section to improve reliability.

[0003]

In the control device having the above-described structure, when one of the field control stations having the dual structure is abnormally stopped, the other is backed up by the other to control the control via the lower communication bus 5. It is possible to continue the operation of the transmitter 7 and the operation terminal 9 connected to the device, but if both of the redundant field control stations become abnormal, the operation and monitoring of the plant become completely impossible. Become. The object of the present invention is to pay attention to this point, and when the field control station 2 or the like abnormally stops, the plant control station 1 or the like directly transmits the plant without passing through the field control station 2 or the like. In order to continue monitoring and operation, the digital signal on the lower communication bus 5 is appropriately converted and a bypass path, that is, a backup gateway for transmitting the digital signal to the higher communication bus 4 is provided.

[0004]

According to the present invention, an operator monitoring console and a field control station or the like are connected by a higher-level communication bus, and the field control station or the like and a transmitter or an operation device installed in a plant are connected. A control device in which devices such as terminals are connected by a lower communication bus has a function of protocol conversion between the upper communication bus and the lower communication bus, and receives a signal indicating abnormality from the field control station or the like. A backup gateway configured to form a communication path between the upper communication bus and the lower communication bus.

[0005]

With the above configuration, the backup gateway which has received the abnormal stop signal from the field control station or the like transmits the digital signal on the lower communication bus,
The protocol is converted and sent out to the upper communication bus. Similarly, the backup gateway converts the operation signal from the operator monitoring console and sends it to the lower communication bus. Therefore, the signal from the field device is
Since it is directly connected to the operator monitoring console, bypassing the control station, the plant can be monitored and operated even if the field control station is abnormal.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. Figure 1
FIG. 2 is a configuration block diagram showing one embodiment of the present invention. In these figures, parts corresponding to the respective parts in FIG. 5 are denoted by the same reference numerals. The device of the present invention has a structural feature in that a backup gateway is added to the configuration conceptual diagram of the control device of FIG. Next, the function and operation of each device will be described. First, referring to FIG. 1, reference numeral 1 denotes an operator monitoring console (hereinafter referred to as O) using a microprocessor or the like.
PS1), and performs various displays and operations necessary for operation of the control device. In addition, various peripheral devices and a field control station 2 are connected by an upper communication bus 4.
(Hereinafter referred to as FCS2) and the backup gateway 3. Since the high-order communication bus 4 performs high-speed communication, a coaxial cable is appropriately used.

In the OPS 1, the display control means 11
On the screen of the display means (CRT) 12, a screen necessary for monitoring and operation, usually via the FCS 2, is displayed. FCS
If 2 is abnormal, a screen necessary for monitoring and operation via the backup gateway 3 is displayed. The FCS control unit 13 usually manages the control operation performed by the FCS 2, but when detecting that the FCS 2 is abnormal, its own function performs a process at the time of the abnormality and takes over the control management to the backup gateway control unit 14.

[0008] Backup gateway control means 14
Manages the operation of the backup gateway 3 when the FCS 2 is abnormal, and enables measurement and control signals to be transmitted and received from the OPS 1 to the transmitter 7, the operation terminal 9, and the like. The operation unit 15 performs commands and data operations for the peripheral device, the FCS 2, the backup gateway 3, the transmitter 7, the operation terminal 9, and the like using a keyboard, a pointing device, and the like. The self-diagnosis unit 17 detects a program abnormality, a hardware abnormality, a power supply abnormality, and the like, and performs display according to the abnormality level. The communication interface 18 has an interface function for performing communication between the FCS 2 and the backup gateway 3 via the upper communication bus 4.

In the field control station 2 (FCS2), the upper communication interface 21
Is connected to the upper communication bus 4, and the measurement control means 22 performs monitoring control of a measurement signal, an alarm, feedback control operation such as PID, logic operation of sequence control, and the like, and generates a control signal. The self-diagnosis means 23 detects a program error,
An abnormality signal is output from the failure signal input / output interface 24 by detecting a hardware abnormality, a power supply abnormality, or the like. The lower communication interface 25 is connected to the lower communication bus (field bus) 5, and exchanges measurement signals and control signals with the transmitter 7 and the operation terminal 9.

The backup gateway 3 is a device that physically and logically matches so that signals can be transmitted and received between the upper communication bus 4 and the lower communication bus 5.
This communication protocol is a protocol. The host communication interface 31 connects to the host communication bus 4. The communication data processing means 32 mutually converts the protocol for transmitting the signal of the lower communication bus 5 to the upper communication bus 4 or for transmitting the signal in the reverse direction. In addition, it has functions such as changing signal paths and buffering data. Self-diagnosis means 3
Reference numeral 3 detects a program error, a hardware error, a power error, and the like. The failure signal input / output interface 34 is
When an abnormal signal is input from the failure signal input / output interface 24 in S2, a communication path change process is performed to form a communication path between the upper communication bus 4 and the lower communication bus 5. The lower communication interface 35 is connected to the lower communication bus 5 and exchanges measurement signals and control signals with the transmitter 7, the operation terminal 9, and the like.

Referring to FIG. 2, a lower communication bus (field bus) 5 includes a transmitter 7 and an operation terminal 9 installed in a plant.
And the like, and a signal wiring for connecting the FCS 2 and the backup gateway 3 to each other, and a digital signal and a DC power supply as necessary. In the case of low speed, a twisted electric wire or the like is appropriately used. Reference numeral 6 denotes a detection sensor unit. The pressure, position, temperature, flow rate, and the like are detected by the respective detection sensors and transmitted to the detected amount conversion means 73.

The transmitter 7 is connected to the lower communication bus 5 by a communication interface 71. Data storage means 72
Is the detection end number, detection conversion data, detector measurement span,
Stores constant data such as parameter setting values. The detection amount conversion unit 73 converts a signal from the detection sensor unit 6, for example, a thermocouple electric signal or the like so as to conform to a predetermined protocol. The self-diagnosis unit 74 detects an abnormality of each unit including the detection sensor unit 6. The above-described various measurement signals and control signals are transmitted to the FCS 2 or the backup via the communication interface 71 and the lower communication bus 5.
Transferred to and from Gateway 3. The driving power is supplied by being superimposed on the lower communication bus 5 or supplied from a separately provided power terminal.

The operation terminal 9 is connected to the lower communication bus 5 via a communication interface 91, and performs predetermined signal conversion of data such as an opening signal, a change of a measurement span, a setting / change of a parameter, and a result of a self-diagnosis. And sends the data to the lower communication bus 5 and reversely converts various data and control signals on the lower communication bus 5 and sends them to the internal circuit. The data storage unit 92 stores an operation terminal number, an operation signal value, an operation range, unique characteristic data, and the like. The control signal / power conversion means 93 responds to the increase or decrease of the operation signal sent to the lower communication bus 5 from the operation of the OPS 1 or from the FCS 2, and a predetermined air pressure is applied to the pneumatic valve and a predetermined air pressure is applied to the electric valve. Provide forward or reverse rotation of the motor to operate the valve opening. The opening value is detected by a detection sensor unit attached to the valve body, and sent out to the lower communication bus 5 via the valve opening value conversion means 94 and the communication interface 91. The self-diagnosis unit 95 detects an abnormality of each part including the valve body 8. The DC power supply for driving the operation terminal 9 is the same as that of the detection terminal 7 described above. In addition, compressed air AS or electric power PS is supplied as power for driving the valve element 8.

According to the flowcharts of FIGS. 3 and 4, F
The switching operation when there is an abnormality in CS2 will be described. In a normal state, data on the upper communication bus 4 and the lower communication bus 5 is constantly taken into a data area provided on the data buffer memory of the backup gateway 3 at a constant cycle. This includes a transmitter number from a transmitter, various data, valve opening data, valve operation data with a valve number from OPS1, and the like. 1) The OPS 1 detects that an abnormality has occurred in the FCS 2 through the upper communication bus 4. 2) OPS1 starts the abnormality processing program and performs the following processing. The signal from the FCS 2 is disconnected from the upper communication bus 4. Activate the backup gateway control. The backup gateway 3 requests a start request and communication.

3) The backup gateway 3 has an F
It determines that FCS2 is abnormal from the signal output by the alarm input / output interface of CS2. 4) The backup gateway 3 starts the program at the time of abnormality and performs the following processing. The data in the data buffer table is converted and output to the upper communication bus 4. The operation signal data on the upper communication bus 4 is converted and stored in the data buffer table. The previous operation signal data is compared with the new data, and if there is a change, it is output to the lower communication bus 5. In this way, the detection end 7 and the operation end 9 are directly monitored and operated from the OPS 1 until the FCS 2 is restored.

In the above description with reference to FIGS. 3 and 4, F
When the CS2 is abnormal, the order in which the OPS1 activates the abnormality processing program first, and then activates the backup gateway, is not limited thereto.
The backup gateway that has received the abnormal signal from S2 may be in an operation order for immediately forming a signal path between the upper communication bus and the lower communication bus. Further, the function of the backup gateway may be accommodated in a cubicle of FCS2 or PLC.

[0017]

According to the present invention, by providing the backup gateway 3, even when the FCS 2 or the PLC or the like is abnormally stopped, it is possible to monitor and operate the field devices from the upper OPS 1, thereby monitoring the plant. Since the operation can be performed more reliably, a great effect can be expected for ensuring safety in an emergency.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a view following FIG. 1; Shows the field device side.

FIG. 3 is a flowchart showing an operation.

FIG. 4 is a view following FIG. 3; Indicates the backup gateway side.

FIG. 5 is a conceptual diagram of a configuration of a conventional control device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Operator monitoring console 2 Field control station 3 Backup gateway 4 Upper communication bus 5 Lower communication bus 6 Detection sensor unit 7 Transmitter 8 Valve body 9 Operation terminal 11 Display control means 12 Display means (CRT) 13 FCS control means 14 Backup gateway Control means 15 Operating means 16 Keyboard and others 17, 23, 33, 74, 94 Self-diagnosis means 18, 21, 31, 25, 35, 71, 91 Communication interface 22 Measurement control means 24, 34 Failure signal input / output interface 32 Communication data Processing means 72, 92 Data storage means 73 Detection amount conversion means 93 Control signal / power conversion means 95 Valve opening value detection conversion means IF interface PS Power supply AS Power supply pressurized air

Claims (1)

(57) [Claims] 1. An upper-level communication bus is connected between an operator monitoring console and a field control station.
A control device that connects the field control station and field devices such as transmitters and operating terminals installed in the plant with a lower-level communication bus provides a protocol conversion function between the upper-level communication bus and the lower-level communication bus. A backup gateway is provided to form a communication path between the upper communication bus and the lower communication bus in response to a signal indicating an abnormality from the field control station. A control device, wherein field devices can be monitored and operated from an operator monitoring console via the backup gateway.