JPS60159902A - Duplex system programmable controller - Google Patents

Abstract

PURPOSE:To raise the rate of operation, and also to obtain an economical duplex system programmable controller by constituting the titled controller so that a sub-system executes a main control when a fault is generated in a main system, and the main system executes an auxiliary control as a sub-system when the fault is reset. CONSTITUTION:A signal from a plant 50 is read by an input device 30, and read in internal storage devices 12, 22, respectively by the respective operation processors 11, 21 of programmable controllers 10, 20. Subsequently, a main control is executed by the programmable controller 10 of a main system, and an auxiliary control is executed by the programmable controller 20 of a sub-system. These operation results are outputted to the plant 50 through an output device 40. Also, a state that the programmable controller 10 of the main system is normal or faulty is inputted to a state input part 24 of the programmable controller 20 of the sub-system, through a state output part 13, and on the other hand, a state that the programmable controller 20 of the sub-system is normal or faulty is inputted to a state input part 14 of the programmable controller 10 of the main system through a state output part 23. In this way, they can be backed up mutually when they are faulty.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a controller for controlling plant processes, and particularly to a dual system programmable controller.

[Technical background of the invention and its problems] In general, the contents of plant operation control include FTI control, which requires commercial reliability and which requires interruption of the operation control as much as possible, and interruption in the event of an emergency. However, there are auxiliary controls that do not pose a risk of causing fatal malfunctions to plant operation control.

When this, tL, etc. plant is controlled by a programmable controller, the system configuration for the main control is controlled by a system programmable controller due to reliability requirements.On the other hand, for the auxiliary control, the main control A method is adopted in which control is performed using one programmable controller in addition to the programmable controller.

The system programmable controller that performs the main control is equipped with two programmable controllers with the same processing capacity, and receives signals from the plant so that the dual controllers perform the same processing. Then, while comparing the results with each other, the main system outputs No. 46 to the plant, which controls the plant. In the event that the main system fails, the sub system backs up the main system. By continuing, plant control can be operated without interruption.

In other words, unless the main system fails, the sub system always executes the same processing as the main system, so if the operating rate of a dual system programmable controller equipped with dual programmable controllers is calculated as follows: What was desired was not an effective way to utilize the space, but an improvement in its operating rate.

[Objective of the Invention] The object of the present invention is to provide a system in which the main system always performs main control of the plant, the subsystem performs auxiliary control of the plant, and when the raw silk fails, the subsystem backs up the yarn. However, the present invention proposes a dual system programmable controller that improves the operating rate of the dual system programmable controller.

[Summary of the invention] A main system that performs main control of the plant and a subsystem that performs auxiliary control of the plant are provided, and when a failure occurs in the main system and it becomes impossible to perform main control of the plant, the subsystem performs main control of the plant in place of the main system, and when the failed main system is successfully restarted, it operates as a subsystem and becomes the plant's auxiliary fl.
ii control is performed.

[Embodiment of the Invention] The present invention will be described below with reference to an embodiment based on the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. The programmable controllers 10 and 211 are duplicated, with the programmable controller IO being the main system and the programmable controller 2° being the sub system.

No. 1d from the plant 50 is read by the input device 3o, and stored in the internal storage device 12 by each arithmetic processing unit 11, 22 of the programmable controller 10.20.
．． 22. The main programmable controller 10 performs main control, and the sub-system programmable controller 2o performs auxiliary control.

These calculation results are sent to the plant 50 via the output device 4o.
It is now output to . Further, the status of whether the main programmable controller 1o is normal or malfunctioning is input to the status input unit U of the sub-system programmable controller 20 via the status output unit 13, while the sub-system programmable controller 20 is normal. The status of failure is inputted via the status output unit 23 to the status input unit 14 of the main programmable controller IO. by this,
This allows for mutual backup in the event of a breakdown.

FIG. 2 is an explanatory diagram showing the operation when both the main system and the sub system are normal. Input device? L30 starts the plant input data reading program 60 and reads input signals related to main control and auxiliary control of the plant. Then, the main system and sub system arithmetic processing units 11 and 21 start the main system input reading program 61 and the sub system input reading program 62, respectively, and the main system internal storage device 12 starts.

The same data is read into the internal storage devices 22 of the subsystems. After inputting this data, the main system arithmetic processing unit 11 executes the sequence processing program 63 for the main control of the plant, and the subsystem arithmetic processing unit 21#:t executes the sequence processing program 64 for the auxiliary control of the plant independently for each system. to be executed. The system that has completed the processing of the sequence processing programs 63 and 64 notifies the other system of the completion of the sequence processing operation. Once both systems have completed their sequence processing operations,
In other words, normally, the completion of main control calculations of the main plant is given high priority, so when the processing of the main system is completed, the main system 10 sends the main control of the plant to the subsystem 2o. Data necessary for control is stored in the main internal storage [12
Data is transferred from there to the internal storage device 22 of the subsystem. In addition, output data related to auxiliary control is stored in the internal storage device 22 of the subsystem.
Data is transferred from there to the main internal storage device 12. This is executed by starting the data transfer program 65.

Since data is transferred in this way, the sub-systems that are not in charge of the main control of the plant will always store critical data necessary for the main control of the plant. When the data transfer is completed between the main system 9 rule threads, raw silk 10 is a plan) 5
0, an output signal for main control and an output signal for auxiliary control are outputted via output device 4o.

This is done by starting the plant data output program 66.

Next, the operation of this dual system programmable controller when a failure occurs in the main system 10 will be described.

As mentioned above, the status of the main system, ie, whether it is normal or faulty, is transmitted to the status input unit 24 of the sub-system via the status output unit I3 of the main system, and conversely, the status of the sub-system is transmitted to the status input unit 23 of the sub-system. FIG. 3 shows an example of the program startup timing when a failure occurs in the main system IO during the cycle of Tl shown in FIG. When the subsystem 20 detects a failure in the main system from the status input section, it switches the output to the output device 40 from the main system to its own system. Then, the sequence processing program 64 of the auxiliary control that is being processed at that point.
The process continues, and when it is completed, it outputs an output signal related to the auxiliary control, and outputs the same value as the previous output for the main control.Then, from the next cycle, the subsystem 20 outputs the output signal related to the auxiliary control. It takes over control and continues the main control as a single programmable pulley roller. In addition, even at the time of this standalone operation, the amount of input data that is included in the WC from the plant is the same as before the failure, both data related to the main control and auxiliary control are read every cycle, and the output is related to the main control. If a failure occurs in the primary system 10 during the cycle T2 in FIG. 2, the secondary system 20 will detect the failure in the primary system in the same way as described above. Then, the subsystem switches the output to the output device 40 to its own system, takes over the main control of the plant immediately from the next Tl cycle, and continues the main control as a programmable controller for the -41j system alone.

On the two sides mentioned above, the system IO in which the failure has occurred will send as much as possible 11) a notification to the status output unit 13 that it has been restored to the system 20 that is performing the main control of the lifting platform that has been successfully restarted and the plant; and the status input unit 22. The subsystem 2υ whose return has been confirmed will be internally recorded 1 from the next cycle.
．． The contents of the system 22 are transferred to the internal storage device I2 of the restored system, and the main system 1O becomes the subsystem and takes charge of auxiliary control of the plant, becoming a programmable controller with a two-way system configuration. On the contrary, if the subsystem 20 that was performing auxiliary control fails, the main system 10 detects the failure of the subsystem 20 and outputs only a signal related to the main control of the plant to the plant via the output device 40. The failed subsystem 20 tries to restart as much as possible, and if the restart is successful, it notifies the main system 1O of the recovery and confirms the recovery of the subsystem 1 (1: The contents of its internal storage device 12 are The data is transferred to the internal storage device 22 of the subsystem, and the subsystem 20 resumes auxiliary control of the ladling plant.

[Effects of the Invention] As described above, the present invention performs two types of control with high and low priorities in one dual-system programmable controller, and
Regarding high-priority control, since it is possible to provide a backup function, it is possible to improve the operating rate and provide an economical dual-system programmable controller.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of the dual system programmable controller of the present invention, Fig. 2 is an explanatory diagram of program start timing in the present invention, and Fig. 3 is an explanatory diagram of program start timing when a failure occurs. be. 10.21J...Programmable controller 11
, 21...Arithmetic processing unit 12.22...Internal storage device 13.23...Status output section 14, 24...Status input section 60...Plant input data reading program 61...Raw silk input ηiP inclusion program 62...
・Subsystem input VC import program 63...Main control sequence processing program 64...Auxiliary control sequence processing 3jl program 65...Data conversion program 66...Plant data output program 70...Failure occurrence proxy Person Patent Attorney Nori Sou Chika (1 person) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a dual-system programmable controller that controls a plant, a main system that performs main control of the plant, a subsystem that performs auxiliary control of the plant, and a state in which the states of these main systems and systems are mutually transmitted. and an output section, when a failure occurs in the main system, the sub system performs the main control in place of the main system, and when the main system fails, the main system controls the main system as the side system. A 21-series programmable controller whose main feature is that it performs control.