JPH08123503A - Plant controller - Google Patents

Abstract

PURPOSE: To simplify the circuit of a remote input device and to improve reliability by providing a serial data switching circuit for selecting either the data of a present system or the data of the other system as serial transmission data to a main controller. CONSTITUTION: Serial data switching circuits (A) 36A and (B) 36B are newly provided. The serial data switching circuit (A) 36A inputs serial data (g) of the present system, serial data (h) of the other system and a switching instruction (i) from a command analysis circuit (A) 32A and an output (d) is connected to a host main controller (A). While the system A is normally used, the output (d) is defined as the serial data (g) of the present system. While the system A is set on standby, corresponding to the switching instruction (i) from the command analysis circuit (A) 32A, the output (d) is operated to be the serial data (h) of the opposite side system and the serial data (h) of the active system, namely, the system B are transmitted to the high-order controller (A).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plant control device for inputting and controlling data from various equipments of a plant.

[0002]

2. Description of the Related Art FIG. 2 shows a plant control system having a standby redundant configuration. In FIG. 2, 1A and 1B are a main control device (A) and a main control device (B), 2 is a remote input device, a remote control device (A) 3A, a remote control device (B) 3B, and an input circuit 4 Consists of. The redundant range in FIG. 2 is up to the main controller and the remote controller, and the input circuit is a single configuration example.

Now, the A system, that is, the main controller (A)
1A and remote control device (A) 3A in regular system (control system)
Then, the B system, that is, the main control device (B) 1B and the remote control device (B) 3B are used as the standby system. Generally, in a standby redundant configuration, when the regular system detects a failure of its own system by self-diagnosis etc., it gives up the regular right and stops the control, and at the same time, the standby system detects the behavior of the other system. It becomes a regular system and begins control.

In order to eliminate the disturbance (for example, the change of the valve opening and the blinking of the display) given to the controlled object at the time of this switching, the system operating as the standby system always receives the same data as the data input by the regular system. After inputting, execute the same control program as the regular system and keep the same state as the regular system.

As described above, in the standby redundancy configuration, even if one of the main control unit and the remote control unit having a high failure rate fails, the control can be continued without giving any disturbance to the controlled object. , Used in systems that require high reliability (hot standby method).

In order to realize the above behavior, the input data from the input circuit 4 in FIG. 2 is input to the remote control device (A) 3A through the input data bus a, and the data is remotely controlled through the interface bus b. Device (B) 3B. Each remote control device can send the data to the main control device by serial transmission to make the input data of the main control device the same. The main control unit (A) 1A and the main control unit (B) 1B are connected by an interface bus b1, and both systems exchange information such as reception completion and failure to confirm soundness. There is.

FIG. 3 is a diagram of the remote input device 2 showing the remote control device (A) 3A and the remote control device (B) 3B in detail. Now, explaining the operation of the A system, the command information from the main controller (A) 1A is sent to the serial line c.
Through the serial / parallel conversion circuit (A) 31A, converted into parallel data by the command analysis circuit (A) 32A, and passed to the input control circuit (A) 33A.

When the A system is used regularly, the input control circuit (A) 33
A inputs data from the input circuit 4 through the input data bus a, passes the data to the B system using the data interface circuit (A) 34A, and serial data in the parallel / serial conversion circuit (A) 35A. To the main controller (A) 1A through the serial line d.

The counterpart system B has the same function, but is different in that it is the data input via the data interface circuit (B) 34B as the data to be sent to the main controller (B) 1B. Others are the same as the case of A system.

[0010]

Since the interface bus b is generally composed of a plurality of lines and requires functions such as transmission / reception timing control and response confirmation,
Microprocessors are used for the input control circuits (A) and (B), which has a drawback that the circuit scale becomes large. The present invention has been made to solve the above problems,
An object of the present invention is to provide a plant control device equipped with a standby redundant remote input device having simple components.

[0011]

A plant control device according to [Claim 1] of the present invention comprises a main control device having a duplex configuration,
A remote control device having a redundant configuration and a remote input device including a single input circuit. The main control device and the remote input device are connected by serial lines, and one of the main control devices is used as a normal system and the other is used. In a plant control device with a standby redundant configuration that operates while performing mutual diagnosis with the standby system as a standby system, a serial data switching circuit is provided at the end of the main control device of the remote input device to select the data of its own system and the data of the other system. In addition to the above, it is possible to output data of either the own system or the partner system to the main control device.

The plant control apparatus according to [Claim 2] of the present invention is configured such that, in [Claim 1], the switch of the serial data switching circuit is switched according to an instruction from the main control apparatus.

In the plant control device according to [claim 3] of the present invention, in [claim 1], a dedicated interface bus is provided between the main control devices, and the main controller input data of the normal system is supplied to the main system of the standby system. Input to the control device, and a recovery function for serial data acquisition error was added.

In the plant control apparatus according to [Claim 4] of the present invention, in [Claim 1], the serial line transmission is configured to block-transmit a plurality of commands without issuing sequential commands.

[0015]

The plant control device according to [Claim 1] to [Claim 4] of the present invention replaces the data interface circuit in the remote input device with serial data transmitted to the main control device and other systems. A serial data switching circuit capable of selecting any of the system data is provided for switching input. The changeover switch is instructed by the main control unit, the serial data acquisition error is recovered by the output to the dedicated interface bus provided between the main control units, and the serial transmission is block transmission to reduce the load on the main control unit. Reduced.

[0016]

Embodiments will be described below with reference to the drawings. FIG.
FIG. 3 is a configuration diagram of an embodiment of a plant control apparatus according to [Claim 1] of the present invention. In FIG. 1, the same parts and corresponding parts as in FIG.
In this embodiment, the connecting means by the data interface circuit between the input control circuits shown in FIG. 3 is excluded.
Instead, serial data changeover circuits (A) and (B) are provided and are connected to each other via a changeover switch. That is, a new serial data switching circuit (A) 36A
And (B) 36B are provided. A dedicated interface bus is provided between the main control units as in FIG.

Next, the operation of the system A will be described.
The serial data switching circuit (A) 36A inputs the serial data g of its own system, the serial data h of the partner system, and the switching instruction i from the command analysis circuit (A) 32A, and the output d is the host main controller (A). (Not shown).

When the A system is in normal use, the output d is the serial data g of its own system. Also, when the A system is in standby, the output d operates according to the switching instruction i from the command analysis circuit (A) 32A so as to become the serial data h of the partner system, and the main controller (A) of the higher order operates the normal system. That is, the B-system serial data h is transmitted. In short, the switch of the serial data switching circuit is switched according to an instruction from the command analysis circuit (Claim 2).

Here, at the time of switching in the serial data switching circuit, a CRC error or data underrun (error in which received data is less than a specified amount) occurs in the host main controller.
However, in these cases, the switching instruction is given by an instruction from the main control unit, and it is assumed that an abnormality immediately after switching may occur in the main control unit. It is solved by taking measures.

According to the above embodiment, the functions of the conventional data interface circuits (A) 33A and (B) 33B can be realized by the serial data switching circuits (A) 36A and (B) 36B. That is, a simple structure is achieved in which only the respective serial lines are connected to each other without using the interface bus b of the prior art. Further, the input control circuits (A) 33A and (B) 33B are also simplified because the control by the interface bus b is unnecessary.

Although not shown in FIG. 1, an interface bus is connected between the main control units 1A and 1B as described above, and the interface bus b1 is connected when the main control unit detects a reception error. It has a recovery function by mutually exchanging data between the main control units ([Claim 3]).

According to the above embodiment, the procedure for simultaneously sending the input data from the input circuit to the main controller is as follows:
Since only the switching instruction from the command analysis circuit is controlled, it becomes easier than the conventional data exchange procedure (timing control, response confirmation, etc.) using the interface bus b, and helps to improve reliability.

Further, a plurality of commands are block-transferred from the main control device to the remote control device, instead of transmitting one command at a time. Therefore, the remote control device side can reduce the load on the main control device side by simply adding the command processing circuit to the command analysis circuit ([claim 4]).

The configuration of FIG. 1 including the above embodiment does not require the use of a highly integrated component such as a microprocessor or a memory, and can be realized by a random logic circuit. Therefore, a gate array or a programmable logic device (PLD) is used. )
The size can be reduced by simple means.

[0025]

As described above, according to the present invention, the input data to the main control unit (necessary for the standby redundant configuration) can be made to coincide with each other only by adding the serial data switching circuit, and the remote input unit can be used. The circuit is simplified and the reliability is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a plant control device according to the present invention.

FIG. 2 is a diagram illustrating a conventional technique.

FIG. 3 is a diagram illustrating a conventional technique.

[Explanation of symbols]

 1A, 1B Main control device (A), (B) 2 Remote input device 3A, 3B Remote control device (A), (B) 4 Input device 31A, 31B Series / parallel conversion circuit (A), (B) 32A, 32B Command analysis circuit (A), (B) 33A, 33B Input control circuit (A), (B) 34A, 34B Data interface circuit (A), (B) 35A, 35B Parallel / series conversion circuit (A), ( B) 36A, 36B serial data switching circuit (A), (B)

Claims (4)

[Claims] 1. A dual control main control device, and a remote control device having a redundant configuration and a remote input device comprising a single input circuit. The main control device and the remote input device are connected by serial lines. In the plant control device having a standby redundant configuration in which one of the main control devices operates as a normal system and the other operates as a standby system, a serial data switching circuit is provided at the main control device side end of the remote input device. The plant control device is characterized in that the data of the own system and the data of the partner system can be selected and at the same time, the data of either the own system or the partner system can be output to the main control device. 2. The plant control device according to claim 1, wherein the switch of the serial data switching circuit is switched according to an instruction from the main control device. 3. A dedicated interface bus is provided between the main control units to input the main control unit input data for the normal system to the main control unit for the standby system, and to add a recovery function for the serial data acquisition error. The plant control device according to claim 1. 4. The plant control apparatus according to claim 1, wherein a plurality of commands are block-transmitted without serially issuing commands for serial line transmission.