JPH1124709A - Autonomous decentralized plant control man-machine device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a system for operating plant equipment via a plurality of plant control man-machine devices that operate independently of each other, a plant control man without special hardware server device is required. Enables construction of machine devices. A plurality of man-machine devices connected to a network transmission line via a network control device.
And a control device 3 also connected to the network transmission line 4 via the network control device 2 and a CRT display 1A, K / B1B connected to each man-machine device 1 to realize a plant control man-machine device. The network controller 2 connected to each man-machine device 1 is provided with a writable memory from any of the network controllers 2 to form a common memory, and each memory has a master flag area indicating a master state. And a life / death counter area indicating an operation state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for operating a controller for controlling plant equipment via a plurality of man-machine devices, without requiring a dedicated hardware server device. A plant control man-machine which enables a machine device to independently output control data to a controller (control device) and prevents competing output of control data to the same control target (controller). Related to the device.

[0002]

2. Description of the Related Art Conventionally, in order to operate plant equipment, a controller (control device) for controlling each equipment and a man-machine device for giving instructions to the controller are connected by a network connection device. A system for performing an output command operation is already widely known and has been put to practical use.

[0003]

However, in the above-mentioned prior art plant control system, a dedicated hardware server is installed, and this and the man-machine device are connected to a network by using a plurality of network connection devices. In some cases, a dedicated hardware server is not installed, and a plurality of man-machine devices are connected to the network using a network connection device.

[0004] In the former case, if the server device breaks down, plant control operations from the man-machine device cannot be performed. Therefore, two servers must be installed and duplicated. Until the backup of the standby system is completed, there is a disadvantage that the plant control operation from the man-machine device cannot be performed.

In the latter case, when control operations are performed from a plurality of man-machine devices on the same control target operation end, operation conflict occurs, and commands from other man-machine devices are received later. There is a drawback that priority is given and the operation of the control target operation end may be different from the intended operation.

[0006]

Therefore, in the present invention, in view of the above-mentioned prior art, it is the same as in the prior art that a plurality of man-machine devices and a control device are connected to a network to transmit and receive data. For the connection between the device and the man-machine device, a network connection device having a message communication function and a common memory function capable of referring to a common memory between the control device and the man-machine device is used. By performing transmission and reception through a common memory in the network control device, data transmission and reception to the control device can be performed from each man-machine device.

[0007] In order to prevent operation conflicts when a plurality of man-machine devices operate on the same operating terminal (plant equipment), master management is performed using a message communication function between a plurality of man-machine devices. Then, data output to the control device was made possible by a single man-machine device.

According to the present invention, when configuring a plant control man-machine device including a plurality of man-machine devices, a dedicated server is not required, and each man-machine device operates independently with respect to the control device. It becomes possible, and by limiting the number of man-machine devices that output data to the control device to one by the master management, it is possible to prevent contention of operations from a plurality of man-machine devices to the same control target.

Further, when the man-machine device fails, the failure is automatically detected, and the master is switched to the surviving man-machine device even if the man-machine device which has been operating as the master has failed. Is automatically performed, so that the operation on the control device can be continuously performed without being affected by the failure.

[0010]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows the entire configuration of a self-sustained distributed power plant control man-machine device according to an embodiment in which the present invention is applied to a power plant.

The self-sustained distributed power plant control man-machine device shown in FIG. 1 includes a plurality of control devices (only one is shown in FIG. 1) 3 including a controller for controlling plant equipment, and this control device. And a plurality of man-machine devices 1 connected to the network 4 via the network control device 2 and outputting control data to the control device 3.
And a CRT display 1A and a keyboard (K / B) 1B connected to the man-machine device 1, respectively.

The man-machine device 1 and the control device 3 are connected to the network 4 via the network control device 2, respectively, and the operation command to the control device 3 is transmitted to the CRT display 1A connected to the man-machine device 1. K / B1B
Is output to the network control device 2 via the man-machine device 1 using The operation command output to the network control device 2 is sent to the network 4 and
The data is taken into the control device 3 from the network 4 by the network control device 2 of the control device 3.

Next, a method of realizing a common memory between network control devices will be described with reference to FIG. In FIG. 2, a common memory 22 that is a common memory area can be secured between a plurality of network control devices 2 by periodically matching the memory 21 inside the network control device 2. By reading and writing this common memory 22,
Data can be exchanged between the plurality of network control devices 2.

Referring to FIG. 3, it will be described that each man-machine device can independently transmit and receive data to and from the control device by dividing the unit for reading and writing the common memory 22 for each device. As shown in FIG. 3, when the man-machine device 11, the man-machine device 12, and the control device 3 are connected to the network 4, the common memory 22 is divided into three, and each is divided into the man-machine device 11 and the man-machine device 12. , And a write-only area of the control device 3,
The man-machine device 11 and the man-machine device 12 can output data to the control device independently of each other. However, even if the output data from the man-machine device 11 and the man-machine device 12 are independent, the man-machine device 11 and the man-machine device 12 independently output data to the same control target, Therefore, it is not possible to prevent contention of data output of the same control target.

To prevent this, the master device management of the man-machine device described below is performed. When two or more man-machine devices are connected on the network, one man-machine device is connected to the control device. By controlling data output, contention for data output is prevented.

In the following description, the man-machine device is referred to as C
Abbreviated as PU, the CPU to be operated is the main CPU, the other CPU is the other CPU, and C is used when the CPU is not particularly limited.
A state in which PUi and CPUi are master devices is called a master, and a state in which they are not are called slaves.

Referring to FIG. 4, a method of determining whether the CPUi is alive or dead will be described. In order to determine the alive / dead state of the CPUi, counters 2211 and 2221 that are constantly updated in a state where the CPUi is operating normally (alive state) are provided in the common memory of the CPUi. C
The live / dead counter 2211 of the previous read information 221 of the common memory of PUi is compared with the live / dead counter 2221 of the current read information 222 of the CPUi of the CPUi, and if they match, the dead state of the CPUi is set. The priority of mastering is set as CPUi> CPUi + 1,
The CPUi to be the master is determined based on the life and death state of the CPUi and the priority of mastering.

FIG. 5 shows a procedure for determining a CPU to be a master when there are two CPUs. When the CPU is started, it is first determined whether a master already exists (P50). If the master already exists, the process proceeds to P56, where the fact that the CPU is in the slave state is recorded in the master flag area in the common memory 222 in FIG. 4, and the CPU is set as the slave. If the master does not exist yet, the process proceeds to P51, and the CPU i is notified of the masterization of this CPU, and the process proceeds to P52.
Wait for a response in the delay processing of. In the process of P53, the state (life or death) is determined based on the presence or absence of a response from the CPUi, and if the CPUi is in a dead state, the CPU is started by the master as a CP.
It is determined to be U, and the status of the master is set in the process P55, and the fact that the status is the master is recorded in the master flag area in the common memory 222 of FIG.

If CPUi is in a raw state, the response reported to all CPUs in P54 is determined. If this response is an affirmative response to mastering (a response to approval of this CPU becoming a master), it means that another CPU has yielded due to a low mastering priority. In this case, the CPU becomes the master in the process of P55.

Next, the response to the mastering report will be described with reference to FIG. By the process of P51 in FIG.
When a report of mastering is made to the PU and a response is requested, the CPU that has received the report is assigned from P61 to P64 in FIG.
Process according to the following procedure. First, in P61, the CPU and the CPU i that issued the mastering report are compared based on the mastering priority, and the mastering priority is determined. If the priority of the CPU is low, the process proceeds to P63, where an affirmative report is made to the CPUi, and the CPU itself is set as a slave in the process of P64. On the other hand, if the priority of this CPU is high, P
By making a negative report to CPUi in step 62, the first boot CPU becomes the master CPU;
When CPU and CPUi start up at the same time, concession of mastering based on the mastering priority is guaranteed.

Further, in FIG. 1, the man-machine device 1 stores the state of another man-machine device 1 in the common memory 221 of FIG.
By using the life and death counters 2211 and 2221 shown in FIGS. 22 and 23, the master of the man-machine device 1 can be switched even when the man-machine device fails. FIG. 7 shows an example of a life and death management procedure executed by all man-machine devices at predetermined time intervals during operation of the device. First, in the process of P71, it is determined whether or not this CPU is in a raw state and is a master. If the CPU is in a raw state and is a master, the master state is held. Otherwise, in the process of P72, it is determined whether or not there is another raw master CPUi. If there is another raw master CPUi, that state is maintained. Raw Master C
If there is no other PUi, the process proceeds to P51 in FIG. 5, and the CPU is switched to the master state following the procedure.

Next, a case where control data is output independently from the man-machine device 11 as a master and the man-machine device 12 as a slave will be described with reference to FIG.

The control data output from the man-machine device 11 is written into the memory 21A of the network control device 2A, and at the same time, is stored in the memory 21B of the network control device 2B of the man-machine device 12 by the message communication function of the network control device 2A. Written. Conversely, the control data output from the man-machine device 12 is:
The data is written to the memory 21B of the network control device 2B, and at the same time, is written to the memory 21A of the network control device 2A of the man-machine device 11 by the message communication function of the network control device 2B. Therefore, the memories 21A and 21B always store the same contents, and the man-machine device 11 and the man-machine device 12 share one memory.

For one control operation of the same device,
When the control data is output from the man-machine device 11 and the man-machine device 12, the previously output control data is written to both memories, and the control data is output later until the operation based on the control data ends. Control data cannot be written to the memory. Therefore, two man-machine devices do not compete for a certain operation of the same device.

On the other hand, the network control device 2C of the control device 3 stores the data in the memory 2A each time data is written to the memory 21A or the memory 21B or at a predetermined time interval.
1A and the master flag area of the memory 21B are read out,
In the master state, whichever is checked, the control data written in the memory in the master state (in this case, the memory 21A) is read and sent to the control device 3. The control device 3 is based on the control data sent,
Control each plant equipment. The control device 3 further sends a control result (device state) and a process amount to the network control device 2C, and the network control device 2C writes the data to the memory 21C. The man-machine devices 11 and 12 read the contents of the memory 21C periodically or as needed, and perform necessary processing.

As described above, the memory 21A and the memory 21
Since the storage contents of B are always the same, even when the man-machine device 11 serving as the master goes down, the control is continued using the memory 21B only by switching the master to the man-machine device 12. Can be.

[0027]

According to the self-sustained decentralized plant control man-machine device of the present invention, 1) the man-machine device can output operation commands to the control device independently of each other, thus requiring a dedicated server. 2) It is possible to construct a plant control man-machine device in which the failure of another man-machine device does not affect the operation of the control device. 3) The master can respond to an operation request to the control device from a plurality of man-machine devices. Since management is performed and the output source man-machine device can be unified, it is possible to construct a plant control man-machine device with less conflicting erroneous operation.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an autonomous distributed power plant control man-machine device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating the concept of a common memory of the network control device in the embodiment of the present invention shown in FIG.

FIG. 3 is a diagram illustrating an example of memory division for each device of the common memory illustrated in FIG. 2;

FIG. 4 is a diagram showing a concept of a life and death management method of a man-machine device using a common memory.

FIG. 5 is a flowchart showing the operation of a mastering determination function according to the present invention.

FIG. 6 is a procedure diagram showing a procedure for responding to a mastering report in the procedure of the mastering determining function shown in FIG. 5;

FIG. 7 is a flowchart showing a master switching operation to which the mastering decision function shown in FIG. 5 is applied when a man-machine device fails;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Man-machine device 2, 2A, 2B, 2C Network control device 3 Control device 4 Network transmission line 11, 12 Man-machine device 21, 21A, 21B, 21C Network control device memory 22 Common memory 221 CPUi common memory Previous read information 2211 CPUi common memory last read information life and death counter 222 CPUi common memory current read information 2221 CPUi common memory current read information life and death counter

Claims (4)

[Claims] A control device including a plurality of controllers for controlling plant equipment; a plurality of man-machine devices for outputting control data to the control device;
A network control device having a message communication function for connecting the control device and the man-machine device, a common memory function for referencing a common memory between the control device and the man-machine device, and a network transmission line to which these devices are connected In the self-sustained decentralized plant control man-machine device configured to include the following, independent operation is possible for each man-machine device, and each man-machine device can centralize output for the same operation target. It has a mastering decision function, automatically detects a failure when one of a plurality of man-machine devices fails, and automatically performs master transition by the mastering decision function, thereby The control data output operation to the control device can be continuously performed without being affected by the failure of the man-machine device. Self-distributed plant control man-machine device. 2. The man-machine device and the control device are connected to the network transmission line via a network control device, respectively, and the network control devices connected to the man-machine device are output from the man-machine device, respectively. A memory for storing control data, and writing control data input from the connected man-machine device to the memory, and a network control device connected to another man-machine device by its message communication function. The self-sustained decentralized plant control man-machine apparatus according to claim 1, wherein a common memory function is exhibited by writing the same control data to the memory of the apparatus. 3. A network according to claim 1, wherein said memory is provided with a master flag area for indicating whether a man-machine device connected to a network control device attached to said memory is in a master state or not. 3. The autonomous decentralized plant control man-machine device according to claim 2, wherein the control unit reads control data in a memory in which a master state is displayed and sends the control data to a control device. 4. The memory is provided with a counter area for indicating that a man-machine device connected to a network control device attached to the memory is operating, and each man-machine device has a mastering priority. Is set, and at a predetermined time interval, each man-machine device checks the operation state of the other man-machine device, and when it is confirmed that the master-state man-machine device is not in the operation state, the priority is determined. The autonomous distributed plant control man-machine apparatus according to claim 3, wherein the apparatus operates so that a high man-machine apparatus is used as a master.