JPS61110095A - Plant restarting system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a plant automatic control system using a computer, and in particular, in a plant having a large number of equipment, it is possible to control the emergency operation when the entire plant is stopped due to a power outage, etc. The present invention relates to a system for quickly restarting the entire plant without placing a burden on personnel.

[Background of the invention]

An example of a conventional computer-based automatically controlled plant restart system is shown in FIG. For a facility 3 having an induction motor or the like as a power device 1 and a limit switch or the like as a detection/monitoring device 2 for the operating state of the device, a sequencer 4 is connected via a relay board 5 for each step operation, which is the minimum unit of device operation. control and monitor. These plurality of sequencers receive instructions from the host computer 6 for each mode operation unit, which is a set of step operations, and perform automatic control.

If any factor that requires an emergency stop occurs during automatic control operation of the plant, the computer receives a signal from a millimeter 7, etc. installed in the plant process, and at the same time sends a signal to the monitoring operation panel 8. In addition to notifying the operators by displaying a warning alarm, etc., an emergency stop command is issued to each sequencer of the equipment that is running the mode operation, interrupting the sequence that is being executed, and stopping the operation of all equipment equipment in an emergency. make it stop.

At this time, as shown in FIG. 3, since the operating conditions for automatic operation are not satisfied in each sequencer, the entire sequence of mode operations being executed is reset.

Note that in the case of a power outage, the entire sequence is in the same state as if it had been reset due to power loss.

When it becomes possible to resume operation of the plant, the operator selects each sequencer in sequence on the sequencer operation panel 9, switches them using the multiplexer 10, and links the sequencers with the terminal device t11 and CRT 12 via the communication control device 13. Separately control the progress of step operations within the sequencer.
Requesting the counted step monitoring sequence from the terminal device and displaying it on the CRT, the operator confirming the interrupted step on the CRT, and sequentially issuing commands for each step operation from the sequencer operation panel, By completing the interrupted mode operation, the valley equipment is made ready to start the next mode operation one after another. After all equipment has been moved to the above state, automatic control operation using a computer will be resumed.

As mentioned above, conventional systems have the disadvantage that operators are required to perform very complicated operations when restarting the plant, and it takes a long time to restart automatic computer-controlled operation, and once the plant In the event of an emergency stop due to the loss of a stain source, the operating rate would drop significantly.

[Purpose of the invention]

The present invention has been made in order to eliminate the drawbacks of the prior art, and provides a sequencer for equipment that can quickly restart the plant after an emergency stop without requiring any complicated operations by operators. It is an object of the present invention to provide a plant restart system capable of automatically returning to a state before an emergency stop, restarting the plant, and continuing automatic operation using a computer.

[Summary of the invention]

The present invention stores in advance in a computer the equipment that can be restarted immediately if its operation is interrupted, and the interruption timing at which each equipment can be restarted for each piece of equipment/equipment, and in the event of an emergency stop of the plant, At each sequence step, the state of the sequence is stored in a step monitor in a non-volatile memory layer. When restarting operation (in other words, when the power is restored in the case of a power outage), the stopped status of each sequencer is checked based on the memory contents of the computer, and it is determined whether restart is possible. As a result, the seek / This system automatically returns the sequence state to the state stored in the step monitoring sequence, restarts the system, and quickly returns to automatic operation.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to FIG. 3, #F4, and FIG. 1. FIG. 3 is a soft logic diagram of the sequencer. During automatic plant operation, the operation mode sequence shown in Figure 3 is computer automatic mode, and relay ROO3 is ON.
are doing. Since the equipment is operated by receiving a start command for mode operation from a total of 4 machines at the higher level, the start conditions and operating conditions are determined in the 31st mode automatic operation preparation 7-16 of the 31st N, and RUEI and OE2 are set to ONL. , when a start command is input, ROE4 turns on. As a result, ROE5 turns ONL, and mode automatic operation no-kense 15 turns on relays R and OF1 for step 1 activation. When the equipment completes the operation of step 1, the signal from the completion limit is input to the sequencer and the step 1 completion relay R is activated.
At the same time that OF2 is turned ON, ROF1 is turned OFF'.

When ROF2 is turned on, aopa is turned on and commands to start step 2.

In this way, a series of step operations progresses, and one mode operation is completed. Further, in parallel with this, the step monitoring sequence 14 counts the number of steps of the executed step operation, and uses a non-volatile memory to retain this count even in the event of a power outage. Now, if an emergency stop is applied due to some request while the mode operation is being executed, the mode automatic operation preparation sequence 16 in FIG.
By turning off the operating condition relay ROFJ2,
ROE4. aOE5 is turned off and mode automatic operation 7-
The entire can 15 is turned off. Therefore, the next step operation command is not output to the equipment, and in the sequence, up to which step has been executed is stored only in the step monitoring sequence 14. On the other hand, in Figure 4,
The computer 6 that monitors and controls the plant determines whether each piece of equipment was in automatic operation before the emergency stop and determines whether each piece of equipment can resume automatic operation after the emergency stop (restart permission determination). data) are stored for each step of each piece of equipment. The restart permission determination device 17 is linked with the control computer 6 and the equipment control pot sequencer 4, and sequentially monitors the stop state of each equipment, that is, the stop state of each sequencer, in the step monitoring sequence 14.
At the same time, the restart permission determination data stored in the control computer 6 is sequentially fetched and compared, and each piece of equipment can be restarted to return to automatic operation. We will determine whether or not. After determining whether or not all equipment is capable of restarting and returning to automatic operation using the method described above, if the operator requests it on the computer terminal device 8 or the operation section of the restart command device 18, the restart will be restarted. A restart permission signal is output from the restart command device 18 to the sequencer of each facility that is determined to be capable of restarting. When the sequencer receives the above-mentioned restart permission signal, first in mode automatic operation preparation sequence 16, it resets the emergency stop and turns on the operating condition relay ROEZ. Further, a start command is given to turn on ROE4t-ONL and ROE5. moreover,
In order to return the mode automatic operation sequence 15 to the state immediately before the emergency stop, each step completion relay R is set according to the count counted in the step monitoring sequence 14.
OF2. Forcibly turn on ROF4... For example, in a step monitoring sequence, if the emergency stop occurs after counting up to step 10, the completion relays for steps 1 to 9 can be forcibly turned on using soft logic as shown in FIG. Now, the above mode automatic operation 7
-The sensor enters the state immediately before an emergency stop and returns to automatic operation. Furthermore, for equipment that is determined to be unable to be restarted using the above method, the suspended mode operation is terminated using the conventional method. After all equipment to be used has completed its mode operation, the computer will resume normal automatic operation.

FIG. 1 shows a conceptual diagram of a plant restart system that uses the above method to determine restart permission and command restart when an emergency stop occurs during execution of a mode operation.

〔Effect of the invention〕

According to the present invention, in a plant that has a large number of equipment and is automatically controlled by a computer, when all equipment is brought to an emergency stop, equipment that can be restarted as is is returned to automatic operation all at once. be able to. In other words, at the time of an emergency stop, data for restart permission determination stored in a computer is used, so there is no need for operators to check the stop status of each piece of equipment on the sequencer terminal device.
Since the mode action automatic operation sequence in the sequencer is returned to its original state based on the step monitoring counter, the complicated step action operation by the operator when restarting operation is greatly reduced, which has the effect of reducing the burden on the operator. big,
It is also possible to considerably avoid a decrease in the plant operating rate due to emergency stoppages such as power outages.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of a plant restart system according to the present invention. FIG. 2 is a system configuration diagram showing an example of a system according to the prior art. FIG. 3 is a soft logic diagram of a sequencer according to the prior art, and FIG. 4 is a configuration diagram of a plant restart system according to the present invention. FIG. 5 shows a logic diagram in which the automatic operation sequence is returned to its original state based on the step monitoring step 7 in the sequencer. 1... Power equipment, 2... Detection/monitoring equipment, 3...
Equipment equipment, 4...Sequencer, 5...Relay board, 6
...control computer, 7...detector (power outage detector, etc.)
, 8... Monitoring operation panel, 9... Sequencer switching note, 1
0...Multiplexer, 11...Sequencer terminal equipment, 12...CRT. 13... Communication control device, 14... Step monitoring sequence, 15... Mode operation automatic operation/-cance, 1
6... Mode automatic operation preparation/-kens, 17... Restart permission determination circuit, 18... Restart command device, 19.
. . . Restart permission determination data, 20 . . . Stop state confirmation signal, 21 . . . Restart permission determination signal, 22 . . . Restart command signal.

Claims (1)

[Claims] 1. Control and monitor the operation of each device in the plant,
In a plant automatic control system that uses a sequencer that monitors constantly running sequences using a counter using non-volatile memory and a computer that centrally monitors and controls them above the sequencer, it is possible to prevent abnormal events such as power outages from occurring. When the power is restored after an emergency stop, the stop status of each sequencer is automatically checked based on the contents of the counter,
a restart permission determination device that determines whether each facility can be restarted; and upon receiving a permission signal from the restart permission determination device, automatically converts the restartable sequencer sequence into the state stored in the memory. A plant restart system comprising a restart command device for restarting return automatic operation, and a sequencer having the above functions.